spi: spi-imx: fix off-by-one in mx51 CPU mode burst length

c712c05e46c8 ("spi: imx: fix the burst length at DMA mode and CPU mode")
corrects three cases of setting the ECSPI burst length but erroneously
leaves the in-range CPU case one bit to big (in that field a value of
0 means 1 bit). The effect was that transmissions that should have been
8-bit bytes appeared as 9-bit causing failed communication with SPI
devices.

Link: https://lore.kernel.org/all/20240201105451.507005-1-carlos.song@nxp.com/
Link: https://lore.kernel.org/all/20240204091912.36488-1-carlos.song@nxp.com/
Fixes: c712c05e46c8 ("spi: imx: fix the burst length at DMA mode and CPU mode")
Signed-off-by: Adam Butcher <adam@jessamine.co.uk>
Link: https://msgid.link/r/20240318175119.3334-1-adam@jessamine.co.uk
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix the burst length at DMA mode and CPU mode

For DMA mode, the bus width of the DMA is equal to the size of data
word, so burst length should be configured as bits per word.

For CPU mode, because of the spi transfer len is in byte, so calculate
the total number of words according to spi transfer len and bits per
word, burst length should be configured as total data bits.

Signed-off-by: Carlos Song <carlos.song@nxp.com>
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Fixes: e9b220aeacf1 ("spi: spi-imx: correctly configure burst length when using dma")
Fixes: 5f66db08cbd3 ("spi: imx: Take in account bits per word instead of assuming 8-bits")
Link: https://lore.kernel.org/r/20240204091912.36488-1-carlos.song@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: Use dev_err_probe for failed DMA channel requests

If dma_request_chan() fails, no error is shown nor any information is
shown in /sys/kernel/debug/devices_deferred if -EPROBE_DEFER is returned.
Use dev_err_probe to fix both problems.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Link: https://msgid.link/r/20240110085403.457089-1-alexander.stein@ew.tq-group.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: correctly configure burst length when using dma

If DMA is used, burst length should be set to the bus width of the DMA.
Otherwise, the SPI hardware will transmit/receive one word per DMA
request.
Since this issue affects both transmission and reception, it cannot be
detected with a loopback test.
Replace magic numbers 512 and 0xfff with MX51_ECSPI_CTRL_MAX_BURST.

Reported-by Stefan Bigler <linux@bigler.io>

Signed-off-by: Benjamin Bigler <benjamin@bigler.one>
Fixes: 15a6af94a277 ("spi: Increase imx51 ecspi burst length based on transfer length")
Link: https://lore.kernel.org/r/8a415902c751cdbb4b20ce76569216ed@mail.infomaniak.com
Link: https://lore.kernel.org/r/20231209222338.5564-1-benjamin@bigler.one
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Take in account bits per word instead of assuming 8-bits

The IMX spi driver has a hardcoded 8, breaking the driver for word
lengths other than 8.

Signed-off-by: Stefan Moring <stefanmoring@gmail.com>
Reported-by: Sebastian Reichel <sre@kernel.org>
Fixes: 15a6af94a277 ("spi: Increase imx51 ecspi burst length based on transfer length")
Tested-by: Sebastian Reichel <sre@kernel.org>
Link: https://lore.kernel.org/r/20230917164037.29284-1-stefanmoring@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: switch to use modern name

Change legacy name master/slave to modern name host/target.

No functional changed.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20230807124105.3429709-17-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230714174955.4064174-1-robh@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Rename SPI_MASTER_GPIO_SS to SPI_CONTROLLER_GPIO_SS

Rename SPI_MASTER_GPIO_SS to SPI_CONTROLLER_GPIO_SS and
convert the users to SPI_CONTROLLER_GPIO_SS to follow
the new naming shema.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230710154932.68377-14-andriy.shevchenko@linux.intel.com
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Increase imx51 ecspi burst length based on transfer length

IMX51 supports 4096 bit burst lengths. Using the spi transfer length
instead of bits_per_word increases performance significantly.

Signed-off-by: Stefan Moring <stefan.moring@technolution.nl>
Link: https://lore.kernel.org/r/20230628125406.237949-1-stefan.moring@technolution.nl
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: fix mixing of native and gpio chipselects for imx51/imx53/imx6 variants

Commit 87c614175bbf (spi: spi-imx: fix MX51_ECSPI_* macros when cs >
3) ensured that the argument passed to the macros was masked with &3,
so that we no longer write outside the intended fields in the various
control registers. When all chip selects are gpios, this works just
fine.

However, when a mix of native and gpio chip selects are in use, that
masking is too naive. Say, for example, that SS0 is muxed as native
chip select, and there is also a chip at 4 (obviously with a gpio
cs). In that case, when accessing the latter chip, both the SS0 pin
and the gpio pin will be asserted low.

The fix for this is to use the ->unused_native_cs value as channel
number for any spi device which uses a gpio as chip select.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230602115731.708883-1-linux@rasmusvillemoes.dk
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: add support for SPI_MOSI_IDLE_LOW mode bit

By default, the spi-imx controller pulls the mosi line high, whenever it
is idle. This behaviour can be inverted per CS by setting the
corresponding DATA_CTL bit in the config register of the controller.

Also, since the controller mode-bits have to be touched anyways, the
SPI_CPOL and SPI_CPHA are replaced by the combined SPI_MODE_X_MASK flag.

Signed-off-by: Boerge Struempfel <boerge.struempfel@gmail.com>
Link: https://lore.kernel.org/r/20230530141641.1155691-3-boerge.struempfel@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: set max_native_cs for imx51/imx53/imx6 variants

The ecspi IP block on imx51/imx53/imx6 have four native chip
selects. Tell that to the spi core so that any non-gpio chip selects
get validated against that upper bound.

Also set the SPI_MASTER_GPIO_SS so that the core verifies that, in the
case where both native and gpio chip selects are in use, there is at
least one leftover native chip select (or "channel", in the ecspi
language) for use by the slaves sitting on gpio chip selects.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230425134527.483607-3-linux@rasmusvillemoes.dk
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: use "controller" variable consistently in spi_imx_probe()

Near the top of the function, spi_imx->controller is set to
controller (and is of course never modified again). The rest of the
function uses a mix of the two expressions.

For consistency, readability and better code generation, drop all the
spi_imx-> indirections.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230425134527.483607-2-linux@rasmusvillemoes.dk
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Use devm_platform_get_and_ioremap_resource()

According to commit 890cc39a8799 ("drivers: provide
devm_platform_get_and_ioremap_resource()"), convert
platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230328062600.93160-1-yang.lee@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: fix MX51_ECSPI_* macros when cs > 3

When using gpio based chip select the cs value can go outside the range
0 – 3. The various MX51_ECSPI_* macros did not take this into consideration
resulting in possible corruption of the configuration.

For example for any cs value over 3 the SCLKPHA bits would not be set and
other values in the register possibly corrupted.

One way to fix this is to just mask the cs bits to 2 bits. This still
allows all 4 native chip selects to work as well as gpio chip selects
(which can use any of the 4 chip select configurations).

Signed-off-by: Kevin Groeneveld <kgroeneveld@lenbrook.com>
Link: https://lore.kernel.org/r/20230318222132.3373-1-kgroeneveld@lenbrook.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230306065733.2170662-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Don't skip cleanup in remove's error path

Returning early in a platform driver's remove callback is wrong. In this
case the dma resources are not released in the error path. this is never
retried later and so this is a permanent leak. To fix this, only skip
hardware disabling if waking the device fails.

Fixes: d593574aff0a ("spi: imx: do not access registers while clocks disabled")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230306065733.2170662-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Replace all spi->chip_select and spi->cs_gpiod references with function call

Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod
members of struct spi_device to be an array. But changing the type of these
members to array would break the spi driver functionality. To make the
transition smoother introduced four new APIs to get/set the
spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and
spi->cs_gpiod references with get or set API calls.
While adding multi-cs support in further patches the chip_select & cs_gpiod
members of the spi_device structure would be converted to arrays & the
"idx" parameter of the APIs would be used as array index i.e.,
spi->chip_select[idx] & spi->cs_gpiod[idx] respectively.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver
Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi
Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part
Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: remove unused struct spi_imx_devtype_data::disable_dma callback

In commit 7a908832ace7 ("spi: imx: add fallback feature") the last
user of the struct spi_imx_devtype_data::disable_dma callback was
removed. However the disable_dma member of struct spi_imx_devtype_data
and the callback itself was not removed.

Remove struct spi_imx_devtype_data::disable_dma and mx51_disable_dma()
as they are unused.

Cc: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20221021131051.1777984-1-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: spi_imx_transfer_one(): check for DMA transfer first

The SPI framework checks for each transfer (with the struct
spi_controller::can_dma callback) whether the driver wants to use DMA
for the transfer. If the driver returns true, the SPI framework will
map the transfer's data to the device, start the actual transfer and
map the data back.

In commit 07e759387788 ("spi: spi-imx: add PIO polling support") the
spi-imx driver's spi_imx_transfer_one() function was extended. If the
estimated duration of a transfer does not exceed a configurable
duration, a polling transfer function is used. This check happens
before checking if the driver decided earlier for a DMA transfer.

If spi_imx_can_dma() decided to use a DMA transfer, and the user
configured a big maximum polling duration, a polling transfer will be
used. The DMA unmap after the transfer destroys the transferred data.

To fix this problem check in spi_imx_transfer_one() if the driver
decided for DMA transfer first, then check the limits for a polling
transfer.

Fixes: 07e759387788 ("spi: spi-imx: add PIO polling support")
Link: https://lore.kernel.org/all/20221111003032.82371-1-festevam@gmail.com
Reported-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reported-by: Fabio Estevam <festevam@gmail.com>
Tested-by: Fabio Estevam <festevam@gmail.com>
Cc: David Jander <david@protonic.nl>
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Link: https://lore.kernel.org/r/20221116164930.855362-1-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: Fix spi_bus_clk if requested clock is higher than input clock

In case the requested bus clock is higher than the input clock, the correct
dividers (pre = 0, post = 0) are returned from mx51_ecspi_clkdiv(), but
*fres is left uninitialized and therefore contains an arbitrary value.

This causes trouble for the recently introduced PIO polling feature as the
value in spi_imx->spi_bus_clk is used there to calculate for which
transfers to enable PIO polling.

Fix this by setting *fres even if no clock dividers are in use.

This issue was observed on Kontron BL i.MX8MM with an SPI peripheral clock set
to 50 MHz by default and a requested SPI bus clock of 80 MHz for the SPI NOR
flash.

With the fix applied the debug message from mx51_ecspi_clkdiv() now prints the
following:

spi_imx 30820000.spi: mx51_ecspi_clkdiv: fin: 50000000, fspi: 50000000,
post: 0, pre: 0

Fixes: 6fd8b8503a0d ("spi: spi-imx: Fix out-of-order CS/SCLK operation at low speeds")
Fixes: 07e759387788 ("spi: spi-imx: add PIO polling support")
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: David Jander <david@protonic.nl>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Marek Vasut <marex@denx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Fabio Estevam <festevam@gmail.com>
Acked-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20221115181002.2068270-1-frieder@fris.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: mx51_ecspi_prepare_message(): skip writing MX51_ECSPI_CONFIG register if unchanged

In mx51_ecspi_prepare_message() the MX51_ECSPI_CONFIG register is
setup for the current spi_message. After writing the register, there
is a delay to ensure that the changes hit the hardware.

This patch checks if the register MX51_ECSPI_CONFIG actually needs to
be changed. If the register content is unchanged the function is left
early, skipping the write to the hardware and the delay. This leads to
a small, but measurable performance increase. For a given workload
with small transfers on an imx6 single core the CPU load decreases
from 30% to ~27%.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-10-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: add PIO polling support

The driver supports several modes, one of them is PIO/IRQ
"spi_imx_pio_transfer()". The data is exchanged with the IP core using
PIO, an IRQ is setup to signal empty/full FIFOs and the end of the
transfer. The IRQ and scheduling overhead for short transfers is
significant. Using polling instead of IRQs can be beneficial to reduce
the overall CPU load, especially on small transfer workloads.

On an imx6 single core, a given RX workload of the mcp251xfd driver
results in 40% CPU load. Using polling mode reduces the CPU load to
30%.

This patch adds PIO polling support to the driver. For transfers with
a duration of less than 30 µs the polling mode instead of IRQ based
PIO mode is used. 30 µs seems to be a good compromise, which is used
the by the SPI drivers for the raspberry Pi (spi-bcm2835,
spi-bcm2835), too.

Co-developed-by: David Jander <david@protonic.nl>
Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-9-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: replace struct spi_imx_data::bitbang by pointer to struct spi_controller

There's no need to embed the struct spi_bitbang into our private
data (struct spi_imx_data), the spi core is flexible enough, so that
we only need a pointer to the allocated struct spi_controller.

This is also a preparation patch to add PIO based polling support to
the driver.

Co-developed-by: David Jander <david@protonic.nl>
Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-8-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: complete conversion from master -> controller

With patch:
| 8caab75fd2c2 ("spi: Generalize SPI "master" to "controller"")
the SPI "master" was generalized to "controller". This patch completed
the conversion of the spi-imx driver by replacing the remaining
occurrences of master to controller.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-7-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: spi_imx_buf_rx_swap_u32(): replace open coded swahw32s()

This patch replaces an open coded swahw32s().

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-6-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: spi_imx_buf_rx_swap_u32(): fix sparse warning: use swab32s() instead of cpu_to_be32()

This patch fixes the following sparse warning by using a swab32s()
instead of a cpu_to_be32(). The driver is used on little endian
systems only and we really want to swap the bytes.

| drivers/spi/spi-imx.c:305:29: warning: incorrect type in assignment (different base types)
| drivers/spi/spi-imx.c:305:29: expected unsigned int val
| drivers/spi/spi-imx.c:305:29: got restricted __be32 [usertype]
| drivers/spi/spi-imx.c:361:21: warning: incorrect type in assignment (different base types)
| drivers/spi/spi-imx.c:361:21: expected unsigned int [assigned] [usertype] val
| drivers/spi/spi-imx.c:361:21: got restricted __be32 [usertype]

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-5-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: mx51_ecspi_intctrl(): prefer 'unsigned int' to bare use of 'unsigned'

This patch fixes the following checkpatch warning, by making val an
"unsigned int".

| WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
| + unsigned val = 0;

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-4-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: avoid unnecessary line continuations

This patch fixes the following checkpatch warning by removing the
trailing backslash:

| WARNING: Avoid unnecessary line continuations
| + spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-3-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: fix sparse warning: add identifier name to function definition

This patch fixes the following and similar sparse warnings by adding
the missing identifier names to the function definitions:

| WARNING: function definition argument 'struct spi_imx_data *' should also have an identifier name
| #68: FILE: drivers/spi/spi-imx.c:68:
| + int (*prepare_message)(struct spi_imx_data *, struct spi_message *);

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220502175457.1977983-2-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: using pm_runtime_resume_and_get instead of pm_runtime_get_sync

Using pm_runtime_resume_and_get() to replace pm_runtime_get_sync and
pm_runtime_put_noidle. This change is just to simplify the code, no
actual functional changes.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Link: https://lore.kernel.org/r/20220414085343.2541608-1-chi.minghao@zte.com.cn
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: add support for SPI_RX_CPHA_FLIP

When SPI_RX_CPHA_FLIP is set, flip CPHA on Rx only transfers. This is
useful to access devices that use inverted CPHA for MISO vs MOSI
signals.

Only support the mx51/mx53 variants for now.

Tested on i.MX6ULL based system.

Signed-off-by: Baruch Siach <baruch.siach@siklu.com>
Link: https://lore.kernel.org/r/e11b4446afe9a46a282dd923d22c27d03fae15f8.1649702729.git.baruch@tkos.co.il
Signed-off-by: Mark Brown <broonie@kernel.org>

dmaengine: imx: Move header to include/dma/

The i.MX DMA drivers are device tree only, nothing in
include/linux/platform_data/dma-imx.h has platform_data in it, so move
the file to include/linux/dma/imx-dma.h.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-By: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20220414162249.3934543-10-s.hauer@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: remove ERR009165 workaround on i.mx6ul

ERR009165 fixed on i.mx6ul/6ull/6sll. All other i.mx6/7 and
i.mx8m/8mm still need this errata. Please refer to nxp official
errata document from https://www.nxp.com/ .

For removing workaround on those chips. Add new i.mx6ul type.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

spi: imx: fix ERR009165

Change to XCH mode even in dma mode, please refer to the below
errata:
https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

spi: imx: Implement support for CS_WORD

This only works when the native chipselect is in use. On a board with a
Ti ADS7950 8 channel ADC. This patch reduces the time to read out all
channels once from 280 us to 20 us.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210727124226.5571-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Simplify logic in spi_imx_push()

For each usage of fifo_words it is clear if ->dynamic_burst is true or
not. This can be used to simplify the function a bit.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20210716173927.2050620-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: mx51-ecspi: Fix CONFIGREG delay comment

For (2 * 1000000) / min_speed_hz < 10 to be true in naturals with zero,
the min_speed_hz must be above 200000 (i.e. 200001 rounds down to 9, so
the condition triggers). Update the comment. No functional change.

Fixes: 6fd8b8503a0dc ("spi: spi-imx: Fix out-of-order CS/SCLK operation at low speeds")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Mark Brown <broonie@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210727160428.7673-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: mx51-ecspi: Fix low-speed CONFIGREG delay calculation

The spi_imx->spi_bus_clk may be uninitialized and thus also zero in
mx51_ecspi_prepare_message(), which would lead to division by zero
in kernel. Since bitbang .setup_transfer callback which initializes
the spi_imx->spi_bus_clk is called after bitbang prepare_message
callback, iterate over all the transfers in spi_message, find the
one with lowest bus frequency, and use that bus frequency for the
delay calculation.

Note that it is not possible to move this CONFIGREG delay back into
the .setup_transfer callback, because that is invoked too late, after
the GPIO chipselects were already configured.

Fixes: 135cbd378eab ("spi: imx: mx51-ecspi: Reinstate low-speed CONFIGREG delay")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210726100102.5188-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: mx51-ecspi: Reinstate low-speed CONFIGREG delay

Since 00b80ac935539 ("spi: imx: mx51-ecspi: Move some initialisation to
prepare_message hook."), the MX51_ECSPI_CONFIG write no longer happens
in prepare_transfer hook, but rather in prepare_message hook, however
the MX51_ECSPI_CONFIG delay is still left in prepare_transfer hook and
thus has no effect. This leads to low bus frequency operation problems
described in 6fd8b8503a0dc ("spi: spi-imx: Fix out-of-order CS/SCLK
operation at low speeds") again.

Move the MX51_ECSPI_CONFIG write delay into the prepare_message hook
as well, thus reinstating the low bus frequency fix.

Fixes: 00b80ac935539 ("spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210703022300.296114-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Use of_device_get_match_data() helper

Use the of_device_get_match_data() helper instead of open coding.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1616385476-53327-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add a check for speed_hz before calculating the clock

When some drivers use spi to send data, spi_transfer->speed_hz is
not assigned. If spidev->max_speed_hz is not assigned as well, it
will cause an error in configuring the clock.
Add a check for these two values before configuring the clock. An
error will be returned when they are not assigned.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Link: https://lore.kernel.org/r/20210408103347.244313-2-xiaoning.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Improve driver description

"SPI Controller driver" is a too generic description.

Make it i.MX specific instead.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20210316180922.239805-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Don't print error on -EPROBEDEFER

This avoids

[ 0.962538] spi_imx 30820000.spi: bitbang start failed with -517

durig driver probe.

Fixes: 8197f489f4c4 ("spi: imx: Fix failure path leak on GPIO request error correctly")
Signed-off-by: Guido Günther <agx@sigxcpu.org>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/0f51ab42e7c7a3452f2f8652794d81584303ea0d.1610987414.git.agx@sigxcpu.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix the unbalanced spi runtime pm management

If set active without increase the usage count of pm, the dont use
autosuspend function will call the suspend callback to close the two
clocks of spi because the usage count is reduced to -1.
This will cause the warning dump below when the defer-probe occurs.

[ 129.379701] ecspi2_root_clk already disabled
[ 129.384005] WARNING: CPU: 1 PID: 33 at drivers/clk/clk.c:952 clk_core_disable+0xa4/0xb0

So add the get noresume function before set active.

Fixes: 43b6bf406cd0 spi: imx: fix runtime pm support for !CONFIG_PM
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Link: https://lore.kernel.org/r/20201124085247.18025-1-xiaoning.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Remove unused .id_table support

Since 5.10-rc1 i.MX is a devicetree-only platform and the existing
.id_table support in this driver was only useful for old non-devicetree
platforms.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20201116202606.29888-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix reference leak in two imx operations

pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in callers(spi_imx_prepare_message and
spi_imx_remove), so we should fix it.

Fixes: 525c9e5a32bd7 ("spi: imx: enable runtime pm support")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201102145835.4765-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix runtime pm support for !CONFIG_PM

525c9e5a32bd introduced pm_runtime support for the i.MX SPI driver. With
this pm_runtime is used to bring up the clocks initially. When CONFIG_PM
is disabled the clocks are no longer enabled and the driver doesn't work
anymore. Fix this by enabling the clocks in the probe function and
telling pm_runtime that the device is active using
pm_runtime_set_active().

Fixes: 525c9e5a32bd spi: imx: enable runtime pm support
Tested-by: Christian Eggers <ceggers@arri.de> [tested for !CONFIG_PM only]
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20201021104513.21560-1-s.hauer@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Fix freeing of DMA channels if spi_bitbang_start() fails

If the SPI controller has has_dmamode = true and spi_bitbang_start() fails
in spi_imx_probe(), then the driver must release the DMA channels acquired
in spi_imx_sdma_init() by calling spi_imx_sdma_exit() in the fail path.

Fixes: f62caccd12c1 ("spi: spi-imx: add DMA support")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Robin Gong <b38343@freescale.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Link: https://lore.kernel.org/r/20201005132229.513119-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: spi_imx_transfer(): add support for effective_speed_hz

This patch implementes the reporting of the effectivly used speed_hz for the
transfer by setting tfr->effective_speed_hz.

See the following patch, which adds this feature to the SPI core for more
information:

5d7e2b5ed585 spi: core: allow reporting the effectivly used speed_hz for a transfer

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200917202420.1914104-1-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Remove unneeded probe message

There is no point in printing a plain "probed" message on successful probe.

Just remove it and make the kernel log a bit less noisy.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20200819123330.22880-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Do not print an error when PIO is used

There are cases that DMA is not used and the driver gracefully
falls back to PIO mode.

Do not treat it like an error message and move it to debug level instead.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20200818223519.8737-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: enable runtime pm support

Enable runtime pm support for spi-imx driver.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Link: https://lore.kernel.org/r/20200727063354.17031-1-xiaoning.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx/fsl-lpspi: Convert to GPIO descriptors

This converts the two Freescale i.MX SPI drivers
Freescale i.MX (CONFIG_SPI_IMX) and Freescale i.MX LPSPI
(CONFIG_SPI_FSL_LPSPI) to use GPIO descriptors handled in
the SPI core for GPIO chip selects whether defined in
the device tree or a board file.

The reason why both are converted at the same time is
that they were both using the same platform data and
platform device population helpers when using
board files intertwining the code so this gives a cleaner
cut.

The platform device creation was passing a platform data
container from each boardfile down to the driver using
struct spi_imx_master from <linux/platform_data/spi-imx.h>,
but this was only conveying the number of chipselects and
an int * array of the chipselect GPIO numbers.

The imx27 and imx31 platforms had code passing the
now-unused platform data when creating the platform devices,
this has been repurposed to pass around GPIO descriptor
tables. The platform data struct that was just passing an
array of integers and number of chip selects for the GPIO
lines has been removed.

The number of chipselects used to be passed from the board
file, because this number also limits the number of native
chipselects that the platform can use. To deal with this we
just augment the i.MX (CONFIG_SPI_IMX) driver to support 3
chipselects if the platform does not define "num-cs" as a
device property (such as from the device tree). This covers
all the legacy boards as these use <= 3 native chip selects
(or GPIO lines, and in that case the number of chip selects
is determined by the core from the number of available
GPIO lines). Any new boards should use device tree, so
this is a reasonable simplification to cover all old
boards.

The LPSPI driver never assigned the number of chipselects
and thus always fall back to the core default of 1 chip
select if no GPIOs are defined in the device tree.

The Freescale i.MX driver was already partly utilizing
the SPI core to obtain the GPIO numbers from the device tree,
so this completes the transtion to let the core handle all
of it.

All board files and the core i.MX boardfile registration
code is augmented to account for these changes.

This has been compile-tested with the imx_v4_v5_defconfig
and the imx_v6_v7_defconfig.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Robin Gong <yibin.gong@nxp.com>
Cc: Trent Piepho <tpiepho@impinj.com>
Cc: Clark Wang <xiaoning.wang@nxp.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Link: https://lore.kernel.org/r/20200625200252.207614-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add fallback feature

Add fallback pio feature in case dma transfer failed before start.
Besides, another whole pio transfer including setup_transfer will be
issued by spi core, no need to restore jobs like commit bcd8e7761ec9 ("spi:
imx: fallback to PIO if dma setup failure").

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Link: https://lore.kernel.org/r/1592347329-28363-3-git-send-email-yibin.gong@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fallback to PIO if dma setup failure

Fallback to PIO in case dma setup failed. For example, sdma firmware not
updated but ERR009165 workaroud added in kernel.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/1590006865-20900-6-git-send-email-yibin.gong@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: use true,false for bool variable

Fixes coccicheck warning:

drivers/spi/spi-imx.c:1233:2-17: WARNING: Assignment of 0/1 to bool variable
drivers/spi/spi-imx.c:1235:2-17: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Link: https://lore.kernel.org/r/1577159526-33689-3-git-send-email-zhengbin13@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Use dma_request_chan() directly for channel request

dma_request_slave_channel_reason() is:
#define dma_request_slave_channel_reason(dev, name) \
dma_request_chan(dev, name)

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191113094256.1108-5-peter.ujfalusi@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: stop buffer overflow in RX FIFO flush

Commit 71abd29057cb ("spi: imx: Add support for SPI Slave mode") added
an RX FIFO flush before start of a transfer. In slave mode, the master
may have sent more data than expected and this data will still be in the
RX FIFO at the start of the next transfer, and so needs to be flushed.

However, the code to do the flush was accidentally saving this data into
the previous transfer's RX buffer, clobbering the contents of whatever
followed that buffer.

Change it to empty the FIFO and throw away the data. Every one of the
RX functions for the different eCSPI versions and modes reads the RX
FIFO data using the same readl() call, so just use that, rather than
using the spi_imx->rx function pointer and making sure all the different
rx functions have a working "throw away" mode.

There is another issue, which affects master mode when switching from
DMA to PIO. There can be extra data in the RX FIFO which triggers this
flush code, causing memory corruption in the same manner. I don't know
why this data is unexpectedly in the FIFO. It's likely there is a
different bug or erratum responsible for that. But regardless of that,
I think this is proper fix the for bug at hand here.

Fixes: 71abd29057cb ("spi: imx: Add support for SPI Slave mode")
Cc: Jiada Wang <jiada_wang@mentor.com>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add module parameter to control DMA use

Add the boolean module parameter "use_dma" to control the use of DMA by
the driver. There are about two dozen other drivers with a "use_dma"
parameter of some sort.

DMA may allow faster and more efficient transfers than using PIO, but it
also adds overhead for small transfers.

High speed receive operations may be less likely to have issues with
FIFO overflow when using DMA than when using PIO.

The eCSPI appears to insert a 4 bit pause after each word in DMA mode,
not done in PIO mode, which can make DMA transfers 50% slower than PIO.

In some cases DMA may be a net win while in others PIO might be. It
depends on the application. So allow DMA to be enabled or disabled at
the driver level. The default will be to have it enabled when possible.

Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: drop useless member speed_hz from driver data struct

The driver data's member variable just caches the transfer's speed_hz
member. All users of the former now have access directly to the latter.
So fix them to use the uncached value and remove the cache.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: rename config callback and add useful parameters

The config callback is called once per transfer while some things can (and
should) be done on a per message manner. To have unambiguous naming in the
end include "transfer" in the callback's name and rename the
implementations accordingly. Also pass the driver struct and transfer
which allows further simplifications in the following patch.

There is no change in behavior intended here.

Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: style fixes

This change fixes some random style issues that I noticed while debugging
the driver: Remove some double spaces, use tabs for indention instead
of spaces if possible, fix comment style.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.

The relevant difference between prepare_message and config is that the
former is run before the CS signal is asserted. So the polarity of the
CLK line must be configured in prepare_message as an edge generated by
config might already result in a latch of the MOSI line.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add a device specific prepare_message callback

This is just preparatory work which allows to move some initialisation
that currently is done in the per transfer hook .config to an earlier
point in time in the next few patches. There is no change in behaviour
introduced by this patch.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: use PIO mode if size is small

Use PIO mode instead if size is smaller than fifo size, since
dma may be less efficient.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: correct wml as the last sg length

Correct wml as the last rx sg length instead of the whole transfer
length. Otherwise, mtd_stresstest will be failed as below:

insmod mtd_stresstest.ko dev=0
=================================================
mtd_stresstest: MTD device: 0
mtd_stresstest: not NAND flash, assume page size is 512 bytes.
mtd_stresstest: MTD device size 4194304, eraseblock size 65536, page size 512, count of eraseblocks 64, pa0
mtd_stresstest: doing operations
mtd_stresstest: 0 operations done
mtd_test: mtd_read from 1ff532, size 880
mtd_test: mtd_read from 20c267, size 64998
spi_master spi0: I/O Error in DMA RX
m25p80 spi0.0: SPI transfer failed: -110
spi_master spi0: failed to transfer one message from queue
mtd_test: error: read failed at 0x20c267
mtd_stresstest: error -110 occurred
=================================================
insmod: ERROR: could not insert module mtd_stresstest.ko: Connection timed out

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: move wml setting to later than setup_transfer

Current dynamic burst length is based on the whole transfer length,
that's ok if there is only one sg, but is not right in case multi sgs
in one transfer,because the tail data should be based on the last sg
length instead of the whole transfer length. Move wml setting for DMA
to the later place, thus, the next patch could get the right last sg
length for wml setting. This patch is a preparation one, no any
function change involved.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Use the longuest possible burst size when in dynamic_burst

Dynamic burst mode allows to group together multiple words and send them
in one continuous burst. When the number of bytes to be sent is not a
strict multiple of the FIFO entry size (32 bits), the controller expects
the non aligned bits to be sent first.

This commit adds support for this particular constraint, avoiding the
need to send the non-aligned bytes one by one at the end of the
transfer, speeding-up transfer speed in that case.

With this method, a transfer is divided into multiple bursts, limited in
size by the maximum amount of data that the controller can transfer in
one continuous burst (which is 512 bytes).

The non-512 byte part of the transfer is sent first. The remaining bytes
to be transferred in the current burst is stored in the 'remainder'
field.

With this method, the read_u32 field is no longer necessary, and is
removed.

This was tested on imx6 solo and imx6 quad.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: remove unnecessary check in spi_imx_can_dma

The spi_imx_can_dma function computes the watermark level so that
the transfer will fit in exactly N bursts (without a remainder).

The smallest watermark level possible being one FIFO entry per burst, we
can't never have a case where the transfer size isn't divsiible by 1.

Remove the extra check for the wml being different than 0.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Use correct number of bytes per words

The SPI core enforces that we always use the next power-of-two number of
bytes to store words. As a result, a 24 bits word will be stored in 4
bytes.

This commit fixes the spi_imx_bytes_per_word function to return the
correct number of bytes.

This also allows to get rid of unnecessary checks in the can_dma
function, since the SPI core validates that we always have a transfer
length that is a multiple of the number of bytes per word.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Use dynamic bursts only when bits_per_word is 8, 16 or 32

The dynamic bursts mode allows to group together multiple words into a
single burst. To do so, it's necessary that words can be packed into the
32-bits FIFO entries, so we can't allow using this mode with bit_per_words
different to 8, 16 or 32.

This prevents shitfing out extra clock ticks for transfers with
bit_per_word values not aligned on 8 bits.

With that , we are sure that only the correct number of bits is
shifted out at each transfer, so we don't need to mask out the remaining
parts of the words.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Remove duplicate variable assignments

Some fields in struct spi_imx_data are assigned a different value twice
in a row, in spi_imx_setupxfer.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

treewide: devm_kzalloc() -> devm_kcalloc()

The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

devm_kzalloc(handle, a * b, gfp)

with:
devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

devm_kzalloc(handle, a * b * c, gfp)

with:

devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
devm_kzalloc(HANDLE,
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
devm_kzalloc(HANDLE,
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
devm_kzalloc(HANDLE,
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(char) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (COUNT_ID)
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * COUNT_ID
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (COUNT_CONST)
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * COUNT_CONST
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (COUNT_ID)
+ COUNT_ID, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * COUNT_ID
+ COUNT_ID, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (COUNT_CONST)
+ COUNT_CONST, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * COUNT_CONST
+ COUNT_CONST, sizeof(THING)
, ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- SIZE * COUNT
+ COUNT, SIZE
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
devm_kzalloc(HANDLE,
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
devm_kzalloc(HANDLE,
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
devm_kzalloc(HANDLE,
- (E1) * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- (E1) * (E2) * E3
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- (E1) * (E2) * (E3)
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (E2)
+ E2, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * E2
+ E2, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (E2)
+ E2, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * E2
+ E2, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- (E1) * E2
+ E1, E2
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- (E1) * (E2)
+ E1, E2
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- E1 * E2
+ E1, E2
, ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>

spi: imx: Switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Update MODULE_DESCRIPTION to "SPI Controller driver"

Now i.MX SPI controller can work in Slave mode.
Update MODULE_DESCRIPTION to "SPI Controller driver".

Signed-off-by: wangbo <wang.bo116@zte.com.cn>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: do not access registers while clocks disabled

Since clocks are disabled except during message transfer clocks
are also disabled when spi_imx_remove gets called. Accessing
registers leads to a freeeze at least on a i.MX 6ULL. Enable
clocks before disabling accessing the MXC_CSPICTRL register.

Fixes: 9e556dcc55774 ("spi: spi-imx: only enable the clocks when we start to transfer a message")
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: imx: Don't require platform data chipselect array

If the array is not present, assume all chip selects are native. This
is the standard behavior for SPI masters configured via the device
tree and the behavior of this driver as well when it is configured via
device tree.

This reduces platform data vs DT differences and allows most of the
platform data based boards to remove their chip select arrays.

CC: Shawn Guo <shawnguo@kernel.org>
CC: Sascha Hauer <kernel@pengutronix.de>
CC: Fabio Estevam <fabio.estevam@nxp.com>
CC: Mark Brown <broonie@kernel.org>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Fix failure path leak on GPIO request error

If the code that requests any chip select GPIOs fails, the cleanup of
spi_bitbang_start() by calling spi_bitbang_stop() is not done. Add this
to the failure path.

Note that spi_bitbang_start() has to be called before requesting GPIOs
because the GPIO data in the spi master is populated when the master is
registed, and that doesn't happen until spi_bitbang_start() is called.

CC: Shawn Guo <shawnguo@kernel.org>
CC: Sascha Hauer <kernel@pengutronix.de>
CC: Fabio Estevam <fabio.estevam@nxp.com>
CC: Mark Brown <broonie@kernel.org>
CC: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: GPIO based chip selects should not be required

The driver will fail to load if no gpio chip selects are specified,
this patch changes this so that it no longer fails.

It's possible to use all native chip selects, in which case there is
no reason to have a gpio chip select array. This is what happens if
the *optional* device tree property "cs-gpios" is omitted.

The spi core already checks for the absence of gpio chip selects in
the master and assigns any slaves the gpio_cs value of -ENOENT.

Also have the driver respect the standard SPI device tree property "num-cs"
to allow setting the number of chip selects without using cs-gpios.

CC: Mark Brown <broonie@kernel.org>
CC: Shawn Guo <shawnguo@kernel.org>
CC: Sascha Hauer <kernel@pengutronix.de>
CC: Fabio Estevam <fabio.estevam@nxp.com>
CC: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Fix failure path leak on GPIO request error correctly

In commit 974488e4ce1e ("spi: imx: Fix failure path leak on GPIO request
error"), spi_bitbang_start() was moved later in the probe sequence. But
this doesn't work, as spi_bitbang_start() has to be called before
requesting GPIOs because the GPIO data in the spi master is populated when
the master is registed, and that doesn't happen until spi_bitbang_start()
is called. The default only works if one uses one CS.

So add a failure path call to spi_bitbang_stop() to fix the leak.

CC: Shawn Guo <shawnguo@kernel.org>
CC: Sascha Hauer <kernel@pengutronix.de>
CC: Fabio Estevam <fabio.estevam@nxp.com>
CC: Mark Brown <broonie@kernel.org>
CC: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Fix failure path leak on GPIO request error

If the code that requests any chip select GPIOs fails, the cleanup of
spi_bitbang_start() by calling spi_bitbang_stop() is not done.

Fix this by moving spi_bitbang_start() to after the code that requets
GPIOs. The GPIOs are dev managed and don't need explicit cleanup.
Since spi_bitbang_start() is now the last operation, it doesn't need
to be cleaned up in the failure path.

CC: Shawn Guo <shawnguo@kernel.org>
CC: Sascha Hauer <kernel@pengutronix.de>
CC: Fabio Estevam <fabio.estevam@nxp.com>
CC: Mark Brown <broonie@kernel.org>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Add support for SPI Slave mode

Previously i.MX SPI controller only works in Master mode.
This patch adds support to i.MX51, i.MX53 and i.MX6 ECSPI
controller to work also in Slave mode.

Currently SPI Slave mode support patch has the following limitations:
1. The stale data in RXFIFO will be dropped when the Slave does any new
transfer.
2. One transfer can be finished only after all transfer->len data been
transferred to master device
3. Slave device only accepts transfer->len data. Any data longer than this
from master device will be dropped. Any data shorter than this from
master will cause SPI to stuck due to mentioned HW limitation 2.
4. Only PIO transfer is supported in Slave mode.
5. Dynamic burst size adjust isn't supported in Slave mode.

Following HW limitation applies:
1. ECSPI has a HW issue when works in Slave mode, after 64
words written to TXFIFO, even TXFIFO becomes empty,
ECSPI_TXDATA keeps shift out the last word data,
so we have to disable ECSPI when in slave mode after the
transfer completes
2. Due to Freescale errata ERR003775 "eCSPI: Burst completion by Chip
Select (SS) signal in Slave mode is not functional" burst size must
be set exactly to the size of the transfer. This limit SPI transaction
with maximum 2^12 bits. This errata affects i.MX53 and i.MX6 ECSPI
controllers.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix use of native chip-selects with devicetree

The commonly used mechanism of specifying the hardware or native
chip-select on an SPI device in devicetree (that is "cs-gpios = <0>")
does not result in the native chip-select being configured for use.
So external SPI devices that require use of the native chip-select
will not work.

You can successfully specify native chip-selects if using a platform
setup by specifying the cs-gpio as negative offset by 32. And that
works correctly. You cannot use the same method in devicetree.

The logic in the spi-imx.c driver during probe uses core spi function
of_spi_register_master() in spi.c to parse the "cs-gpios" devicetree tag.
For valid GPIO values that will be recorded for use, all other entries in
the cs_gpios list will be set to -ENOENT. So entries like "<0>" will be
set to -ENOENT in the cs_gpios list.

When the SPI device registers are setup the code will use the GPIO
listed in the cs_gpios list for the desired chip-select. If the cs_gpio
is less then 0 then it is intended to be for a native chip-select, and
its cs_gpio value is added to 32 to get the chipselect number to use.
Problem is that with devicetree this can only ever be -ENOENT (which
is -2), and that alone results in an invalid chip-select number. But also
doesn't allow selection of the native chip-select at all.

To fix, if the cs_gpio specified for this spi device is not a
valid GPIO then use the "chip_select" (that is the native chip-select
number) for hardware setup.

Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Tested-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix little-endian build

The newly added dynamic burst code produces a harmless warning
on big-endian configurations:

drivers/spi/spi-imx.c: In function 'spi_imx_buf_rx_swap_u32':
drivers/spi/spi-imx.c:284:15: error: unused variable 'bytes_per_word' [-Werror=unused-variable]
unsigned int bytes_per_word;
^~~~~~~~~~~~~~
drivers/spi/spi-imx.c: In function 'spi_imx_buf_tx_swap_u32':
drivers/spi/spi-imx.c:319:15: error: unused variable 'bytes_per_word' [-Werror=unused-variable]
unsigned int bytes_per_word;

This adds another #ifdef around the variable declaration matching
the one on the use.

Fixes: 1673c81d9435 ("spi: imx: dynamic burst length adjust for PIO mode")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: dynamic burst length adjust for PIO mode

previously burst length (BURST_LENGTH) is always set to equal
to bits_per_word, causes a 10us gap between each word in
transfer, which significantly affects performance.

This patch uses 32 bits transfer to simulate lower bits transfer,
and adjusts burst length runtimely to use biggeest burst length
as possible to reduce the gaps in transfer for PIO mode.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add SPI_NO_CS support

To run spi-loopback-tests on HW without modifications, we need to
disable Chip Select. This should avoid surprising side effects for SPI devices
by testing patterns.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add selection for iMX53 and iMX6 controller

ECSPI contorller for iMX53 and iMX6 has few hardware issues
comparing to iMX51.
The change add possibility to detect which controller is used
to apply possible workaround and limitations.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: introduce fifo_size and has_dmamode in spi_imx_devtype_data

Different ECSPI controller has different fifosize and DMA capability,
instead of calling functions to identify these information by check
devtype. add fifo_size and has_dmamode to spi_imx_devtype_data.
so that these information can be directly accessed.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Check for allocation failure earlier

In case of spi_alloc_master() failure it is better to return the
error immediately, so move the error check right after the allocation.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: rename 'bpw' variables

'bpw' is ambiguous and only the context makes sure if bytes_per_word
or bits_per_word is meant. Use the full names instead to make reading
the code easier.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: remove bytes_per_word from private driver struct

We already have bits_per_word in the private driver struct and
bytes_per_word can be calculated from it, so remove bits_per_word.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: drop bogus unnecessary dma config

It's unnecessary to call spi_imx_dma_configure() from probe(). It will
be called later anyway again when an actual DMA transfer is prepared.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: put struct spi_imx_config members into driver private struct

struct spi_imx_config used to hold data specific to the current
transfer. However, other data is in the drivers private data struct.
Let's drop struct spi_imx_config and put the variables into the
drivers private data struct aswell.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Drop unnecessary check

__spi_validate makes sure that every transfer has a valid bits_per_word
and speed_hz setting. We do not need to fallback to values from the
spi_device.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Nothing to do in setupxfer when transfer is NULL

When the spi_transfer given in spi_imx_setupxfer is NULL then
we have nothing to do. Bail out early in this case so that
we do not have to test for t != NULL multiple times later.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Revert "spi: imx: dynamic burst length adjust for PIO mode"

This reverts commits 8d4a6cad7adb3ddac32cd52635f20e11de11a658 and
179547e143e773f9f866ad3536275ab627711f3a.

Besides the problems already found with this patch it also modifies
the spi transfer tx_buf in spi_imx_u32_swap_u8() and spi_imx_u32_swap_u16().
This is hidden from the compiler with an explicit cast from const void*
to u32*, so no warning is issued.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix issue when tx_buf or rx_buf is NULL

In case either transfer->tx_buf or transfer->rx_buf is NULL,
manipulation of buffer in spi_imx_u32_swap_u[8|16]() will cause
NULL pointer dereference crash.

Add buffer check at very beginning of spi_imx_u32_swap_u[8|16](),
to avoid such crash.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Tested-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: dynamic burst length adjust for PIO mode

previously burst length (BURST_LENGTH) is always set to equal
to bits_per_word, causes a 10us gap between each word in
transfer, which significantly affects performance.

This patch uses 32 bits transfer to simulate lower bits transfer,
and adjusts burst length runtimely to use biggeest burst length
as possible to reduce the gaps in transfer for PIO mode.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi-imx: Implements handling of the SPI_READY mode flag.

This patch implements consideration of the SPI_READY mode flag as
defined in spi.h. It extends the device tree bindings to support
the values defined by the reference manual for the DRCTL field.

Thus supporting edge-triggered and level-triggered bursts.

Signed-off-by: Leif Middelschulte <Leif.Middelschulte@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: adjust watermark level according to transfer length

Previously DMA watermark level is configured to fifosize/2,
DMA mode can be used only when transfer length can be divided
by 'watermark level * bpw', which makes DMA mode not pratical.

This patch adjusts watermark level to largest number (no bigger
than fifosize/2) which can divide 'tranfer length / bpw' for
each transfer.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: set spi_bus_clk for mx21 and mx27

Introduce additional output parameter in spi_imx_clkdiv_1()
function to return result frequency and set it to spi_bus_clk.

This fixes division by zero bug, which occurred in
spi_imx_calculate_timeout() function.

Signed-off-by: Robert Baldyga <r.baldyga@hackerion.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: support DMA for imx35

Support DMA transfers on imx35 and compatible chipsets (imx31, imx25).

If DMA can be used, set the start mode control (SMC) bit to start the
SPI burst as soon as data is written into the tx fifo. Configure DMA
requests when the fifo is half empty during tx or half full during rx.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix error return code in spi_imx_probe()

Fix to return error code -EINVAL if no CS GPIOs available
instead of 0, as done elsewhere in this function.

Fixes: f13d4e189d20 ("spi: imx: Gracefully handle NULL master->cs_gpios")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Gracefully handle NULL master->cs_gpios

It is possible that master->cs_gpios is NULL after spi_bitbang_start(),
this happens if the master has no CS GPIOs specified in DT. Check for
this case after spi_bitbang_start() to prevent NULL pointer dereference
in the subsequent for loop, which accesses the master->cs_gpios field.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Martin Kaiser <martin@kaiser.cx>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: support loopback mode on imx35

imx35 and compatible chipsets support loopback mode by setting a
loopback control bit in the test register. Make this setting available
for data transfers, similar to what we do for imx51.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: set spi_bus_clk for mx1, mx31 and mx35

Modify spi_imx_clkdiv_2() to return the resulting bus clock frequency
when the selected clock divider is applied. Set spi_imx->spi_bus_clk to
this frequency.

If spi_bus_clk is unset, spi_imx_calculate_timeout() causes a
division by 0.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: wait_for_completion_timeout(..) for PIO transfers

In some rare cases I see the following 'task blocked' information. It
looks like the PIO transfer has some problems and never succeeds. Make
use of wait_for_completion_timeout(..) to detect this case and
return -ETIMEDOUT.

[ 240.246067] INFO: task hexdump:1660 blocked for more than 120 seconds.
[ 240.246089] Not tainted 4.1.17 0000001
[ 240.246099] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 240.246109] hexdump D c0575548 0 1660 1 0x00000000
[ 240.246132] Backtrace:
[ 240.246166] [<c057524c>] (__schedule) from [<c0575a84>] (schedule+0x40/0xa4)
[ 240.246176] r10:00000000 r9:c07f1300 r8:c07b8408 r7:c0576518 r6:7fffffff r5:7fffffff
[ 240.246210] r4:ee972e7c
[ 240.246233] [<c0575a44>] (schedule) from [<c0578544>] (schedule_timeout+0x174/0x274)
[ 240.246254] [<c05783d0>] (schedule_timeout) from [<c0576518>] (wait_for_common+0xc0/0x164)
[ 240.246263] r10:00000000 r9:c07f1300 r8:00000002 r7:00000000 r6:7fffffff r5:ee972e78
[ 240.246294] r4:ee972e7c
[ 240.246314] [<c0576458>] (wait_for_common) from [<c05765dc>] (wait_for_completion+0x20/0x24)
[ 240.246324] r10:ee972e50 r8:00000001 r7:c3976200 r6:ee972c00 r5:ee972e50 r4:c2c87d28
[ 240.246367] [<c05765bc>] (wait_for_completion) from [<c03f6b04>] (spi_imx_transfer+0xe8/0x3cc)
[ 240.246393] [<c03f6a1c>] (spi_imx_transfer) from [<c03f50e4>] (spi_bitbang_transfer_one+0xb4/0x250)
[ 240.246403] r10:ee972e50 r8:00000001 r7:00000000 r6:c2c87da0 r5:00000000 r4:c2c87d28
[ 240.246443] [<c03f5030>] (spi_bitbang_transfer_one) from [<c03f36e8>] (__spi_pump_messages+0x36c/0x6b4)
[ 240.246452] r10:ee9e5010 r9:00000001 r8:ee9e5010 r7:00000000 r6:c2c87da0 r5:c2c87d6c
[ 240.246483] r4:ee972c00
[ 240.246503] [<c03f337c>] (__spi_pump_messages) from [<c03f3b68>] (__spi_sync+0x138/0x1e4)
[ 240.246512] r10:00000000 r9:00000000 r8:c03f25a8 r7:00000000 r6:ee972c00 r5:c3976200
[ 240.246542] r4:c2c87da0
[ 240.246562] [<c03f3a30>] (__spi_sync) from [<c03f3c50>] (spi_sync+0x1c/0x20)
[ 240.246571] r10:00040000 r9:00000000 r8:c3976200 r7:00000000 r6:ee973300 r5:c2c87da0
[ 240.246602] r4:ee973014
[ 240.246623] [<c03f3c34>] (spi_sync) from [<c03f0210>] (m25p80_read+0xf8/0x124)
[ 240.246641] [<c03f0118>] (m25p80_read) from [<c03f1528>] (spi_nor_read+0x64/0x80)
[ 240.246651] r10:00004000 r8:00004000 r7:00000000 r6:00040000 r5:00000000 r4:ee973014
[ 240.246698] [<c03f14c4>] (spi_nor_read) from [<c03cdcb4>] (mtd_read+0x98/0xcc)
[ 240.246708] r7:c2c87ea0 r6:ee973098 r5:00000000 r4:001c0000
[ 240.246740] [<c03cdc1c>] (mtd_read) from [<c03d300c>] (mtdchar_read+0xcc/0x204)
[ 240.246750] r9:ed424000 r8:00000000 r7:b495d018 r6:c2c87f78 r5:00000000 r4:00040000
[ 240.246793] [<c03d2f40>] (mtdchar_read) from [<c013b1c4>] (__vfs_read+0x3c/0xe0)
[ 240.246803] r10:00004000 r9:00000000 r8:c2c87f78 r7:b495d018 r6:c2c87f78 r5:c05c8104
[ 240.246833] r4:c32fe600
[ 240.246852] [<c013b188>] (__vfs_read) from [<c013befc>] (vfs_read+0x98/0x154)
[ 240.246861] r10:00000000 r8:00040000 r7:00004000 r6:c2c87f78 r5:b495d018 r4:c32fe600
[ 240.246899] [<c013be64>] (vfs_read) from [<c013c008>] (SyS_read+0x50/0x90)
[ 240.246908] r10:00000000 r8:00040000 r7:b495d018 r6:00004000 r5:c32fe601 r4:c32fe600
[ 240.246953] [<c013bfb8>] (SyS_read) from [<c000fa60>] (ret_fast_syscall+0x0/0x3c)
[ 240.246962] r9:c2c86000 r8:c000fc04 r7:00000003 r6:00004000 r5:00000000 r4:b495d018

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Remove "maybe_unused" attributes

The SPI-driver no longer contains the conditions for various CPUs, so
"maybe_unused" attributes is no longer needed.
This patch removes these attributes.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Remove unnecessary field "mode" from struct spi_imx_config

SPI mode can be obtained directly from spi-device, there is no
need to keep a copy.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Using existing properties for chipselects

Patch reuse existing "chip_select" and "cs_gpio(s)" fields from SPI core.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Fix possible NULL pointer deref

transfer could be NULL in spi_imx_can_dma() when it's called from
spi_imx_setupxfer() with a NULL transfer. Test for a NULL pointer before
dereferencing it.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: only do necessary changes to ECSPIx_CONFIGREG

If the SPI chip select (CS) for a dedicated channel is done manually by
the used higher device driver, the CS may be active while writing to
ECSPIx_CONFIGREG. To prevent unwanted clock edges when selecting
the clock mode, only do the necessary changes to the i.MX SPI
configuration register and leave not selected channels untouched.

To prevent unwanted clock edges on first use, an empty dummy
transmission shall be done by the initialization procedure of the device
driver of this channel. This will set the clock mode to the correct state.

Signed-off-by: Knut Wohlrab <knut.wohlrab@de.bosch.com>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: drop bogus tests for rx/tx bufs in DMA transfer

The driver tries to be clever by only setting up DMA channels when
the corresponding sg tables are non NULL. The sg tables are embedded
structs in struct spi_transfer, so they are guaranteed to be non NULL
which makes the if(tx)/if(rx) tests completely bogus. The driver even
sets the SPI_MASTER_MUST_RX / SPI_MASTER_MUST_TX flags which makes sure
the sg tables are not only present but also non empty.
Drop the tests and make the DMA path easier to follow.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: set MX51_ECSPI_CTRL_SMC bit in setup function

Now that the config function knows whether we are doing DMA or not we
can do the necessary register setup in the config function and no longer
have to do this in the trigger function. With this the trigger function
becomes a no-op for DMA, so instead of testing if we are doing DMA or
not in the trigger function we simply no longer call it in the DMA case.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: make some register defines simpler

The watermark levels in the DMA register are write only, the driver
should never have to read them back from the hardware. Replace the
current _MASK and _OFFSET defines with defines taking the watermark
level directly.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: remove unnecessary bit clearing in mx51_ecspi_config

This reverts patch 1476253cef (spi: imx: fix ecspi mode setup)
The patch tried to fix something by clearing bits in the cfg variable,
but cfg is initialized to zero on function entry. There are no bits to
clear.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add support for all SPI word width for DMA

DMA transfer for SPI was limited to up to 8 bits word size until now.
Sync in SPI burst size and DMA bus width is necessary to correctly
support 16 and 32 BPW.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: drop unncessary dma_is_inited variable

There's no need for an extra dma_is_inited variable when we can
equally well check for the existence of a DMA channel.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: drop unnecessary read/modify/write

When the MX51_ECSPI_DMA is configured we control every single bit
of the register, so there's no need to read/modify/write it. Instead
just write the value we want to have in the register. Also, drop
unnecessary check if we are actually doing DMA. The values written
to the register have no effect in PIO mode and value written there
during the last DMA transfer is still in the register, so we can
equally well always write a value.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: initialize usedma earlier

The SoC specific config function does not know if DMA will be used or
not. This information will be useful to configure the SPI controller
correctly for DMA in following patches, so initialize the usedma
variable before calling into the SoC specific config function.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: drop fallback to PIO

At the moment the driver decides to fallback to PIO mode the buffers
are already mapped for DMA. It's a bug to access them with the CPU
afterwards, so we cannot just fallback to PIO mode.
It should not be necessary anyway, since we only use DMA when we
verified that it's possible in the fist place, so when prep_slave_sg
fails it's a bug, either in the SDMA driver or in the can_dma
implementation.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: replace fixed timeout with calculated

Fixed timeout value can fire while transaction is ongoing. This may happen
because there are no strict requirements on SPI transaction duration.
Dynamic timeout value is generated based on SCLK and transaction size.

There is also 4 * SCLK delay between TX bursts related to HW internal CS change.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix spi resource leak with dma transfer

In spi_imx_dma_transfer(), when desc_rx = dmaengine_prep_slave_sg()
fails, the context goes to label no_dma and then return. However,
the memory allocated for desc_tx has not been freed yet, which leads
to resource leak.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: use proper dev_* functions for driver messages

Add a struct device * member to the private driver data and use
it to print messages using dev_* functions rather than pr_*.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: allow only WML aligned transfers to use DMA

RX DMA tail data handling doesn't work correctly in many cases with current
implementation. It happens because SPI core was setup to generates both RX
and RX TAIL events. And RX TAIL event does not work correctly.
This can be easily verified by sending SPI transaction with size modulus
WML(32 in our case) not equal 0.

Also removing change introduced in f6ee9b582d2db652497b73c1f117591dfb6d3a90
since this change only fix usecases with transfer size from 33 to 128 bytes
and doesn't fix 129 bytes and bigger.

This is output from transaction with len 138 bytes in loopback mode at 10Mhz:
TX0000: a3 97 a2 55 53 be f1 fc f9 79 6b 52 14 13 e9 e2
TX0010: 2d 51 8e 1f 56 08 57 27 a7 05 d4 d0 52 82 77 75
TX0020: 1b 99 4a ed 58 3d 6a 52 36 d5 24 4a 68 8e ad 95
TX0030: 5f 3c 35 b5 c4 8c dd 6c 11 32 3d e2 b4 b4 59 cf
TX0040: ce 23 3d 27 df a7 f9 96 fc 1e e0 66 2c 0e 7b 8c
TX0050: ca 30 42 8f bc 9f 7b ce d1 b8 b1 87 ec 8a d6 bb
TX0060: 2e 15 63 0e 3c dc a4 3a 7a 06 20 a7 93 1b 34 dd
TX0070: 4c f5 ec 88 96 68 d6 68 a0 09 6f 8e 93 47 c9 41
TX0080: db ac cf 97 89 f3 51 05 79 71

RX0000: a3 97 a2 55 53 be f1 fc f9 79 6b 52 14 13 e9 e2
RX0010: 2d 51 8e 1f 56 08 57 27 a7 05 d4 d0 52 82 77 75
RX0020: 1b 99 4a ed 58 3d 6a 52 36 d5 24 4a 68 8e ad 95
RX0030: 5f 3c 35 00 00 b5 00 00 00 c4 00 00 8c 00 00 dd
RX0040: 6c 11 32 3d e2 b4 b4 59 cf ce 23 3d 27 df a7 f9
RX0050: 96 fc 1e e0 66 2c 0e 7b 8c ca 30 42 8f 1f 1f bc
RX0060: 9f 7b ce d1 b8 b1 87 ec 8a d6 bb 2e 15 63 0e ed
RX0070: ed 3c 58 58 58 dc 3d 3d a4 6a 6a 3a 52 52 7a 36
RX0080: 06 20 a7 93 1b 34 dd 4c f5 ec

Zeros at offset 33 and 34 caused by reading empty RX FIFO which not possible
if DMA RX read was triggered by RX event. This mean DMA was triggered
by RX TAIL event.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix spi resource leak with dma transfer

In spi_imx_dma_transfer(), when desc_rx = dmaengine_prep_slave_sg()
fails, the context goes to label no_dma and then return. However,
the memory allocated for desc_tx has not been freed yet, which leads
to resource leak.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: defer spi initialization, if DMA engine is

If SPI device supports DMA mode, but DMA controller is not yet
available due to e.g. a delay in the corresponding kernel module
initialization, retry to initialize SPI driver later on instead of
falling back into PIO only mode.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: return error from dma channel request

On SDMA initialization return exactly the same error, which is
reported by dma_request_slave_channel_reason(), it is a preceding
change to defer SPI DMA initialization, if SDMA module is not yet
available.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: enable loopback only for ECSPI controller family

Limit SPI_LOOP mode to ECSPI controller (iMX.51, iMX53 and i.MX6) only since
there is no support in other families specific code for now.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix loopback mode setup after controller reset

If controller hold in reset it's not possible to write any
register except CTRL. So all other registers must be updated
only after controller bring out from reset.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: add function to check for IMX51 family controller

Similar to other controller type checks add check function for
IMX51. It includes IMX53 and IMX6.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: replace multiple watermarks with single for RX, TX and RXT

There is no need to have different watermarks levels since they are the same.
Merge them into one WML parameter.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: reorder HW operations enable order to avoid possible RX data loss

The overflow may happen due to rescheduling for another task and/or interrupt
if we enable SPI HW before starting RX DMA. So RX DMA enabled first to make
sure data would be read out from FIFO ASAP. TX DMA enabled next to start
filling TX FIFO with new data. And finaly SPI HW enabled to start actual
data transfer.

The risk rise in case of heavy system load and high SPI clock.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: terminate RX DMA transaction in case of TX DMA timeout

Not only TX DMA should be terminated, but RX DMA also. It's required
to avoid accidential DMA memory writes from RX DMA channel and properly
terminate transaction.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Add loopback mode support

Loopback mode can be activated by setting bit LBC (LoopBack
Control) of register ECSPI_TESTREG.

Add support for it.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: fix ecspi mode setup

Fixed problem with setting spi mode 0 or 1 after setting mode 2 or 3

SPI_MODE_0 and SPI_MODE_1 requires clock low when inactive. SPI_MODE_2
and SPI_MODE_3 requires clk high when inactive.
Currently driver can just set bits in fields SCLK_PHA (SPI Clock/Data
Phase Control), SCLK_POL (SPI Clock Polarity Control),
SCLK_CTL (controls the inactive state of SCLK) ans SS_POL (SPI SS
Polarity Select) of ECSPIx_CONFIGREG register.
This patch allows driver to clear corresponding bits in these fields.

Signed-off-by: Andrew Y. Kuksov <qxovxp@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Fix small DMA transfers

DMA transfers must be greater than the watermark level size. spi_imx->rx_wml
and spi_imx->tx_wml contain the watermark level in 32bit words whereas struct
spi_transfer contains the transfer len in bytes. Fix the check if DMA is
possible for a transfer accordingly. This fixes transfers with sizes between
33 and 128 bytes for which previously was claimed that DMA is possible.

Fixes: f62caccd12c17e4 (spi: spi-imx: add DMA support)
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: Constify platform_device_id

The platform_device_id is not modified by the driver and core uses it as
const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: read back the RX/TX watermark levels earlier

They are used to decide if the controller can do DMA on a buffer
of a specific length and thus are needed before any transfer is attempted.

This fixes a memory leak where the SPI core uses the drivers can_dma()
callback to determine if a buffer needs to be mapped. As the watermark
levels aren't correct at that point the driver falsely claims to be able to
DMA the buffer when it fact it isn't.
After the transfer has been done the core uses the same callback to
determine if it needs to unmap the buffers. As the driver now correctly
claims to not being able to DMA the buffer the core doesn't attempt to
unmap the buffer which leaves the SGT leaking.

Fixes: f62caccd12c17e4 (spi: spi-imx: add DMA support)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: spi-imx: use correct enumeration type

The fourth argument of dmaengine_prep_slave_sg needs to be of the
enumeration type dma_transfer_direction instead of dma_data_direction.
Since the used enumeration values actually stay the same, this is not
an actual issue at runtime.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: cleanup wait_for_completion handling

return type of wait_for_completion_timeout is unsigned long not int and
always returns >=0 , this patch adds a suitable return variable and
simplifies the return value checking as there is no < 0 case.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: imx: use pio mode for i.mx6dl

For TKT238285 hardware issue which may cause txfifo store data twice can only
be caught on i.mx6dl, we use pio mode instead of DMA mode on i.mx6dl.

Fixes: f62caccd12c17e4 (spi: spi-imx: add DMA support)
Signed-off-by: Robin Gong <b38343@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: spi-imx: Do not store the irq number in the private structure

The irq number is only used inside the probe function, so there is really no
need to store it in the private structure.

Use a local 'irq' variable to hold the the irq number instead.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: drop owner assignment from platform_drivers

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

spi: spi-imx: add DMA support

Enable DMA support on i.mx6. The read speed can increase from 600KB/s
to 1.2MB/s on i.mx6q. You can disable or enable dma function in dts.
If not set "dma-names" in dts, spi will use PIO mode. This patch only
validate on i.mx6, not i.mx5, but encourage ones to apply this patch
on i.mx5 since they share the same IP.

Note:
Sometime, there is a weid data in rxfifo after one full tx/rx
transfer finish by DMA on i.mx6dl, so we disable dma functhion on
i.mx6dl.

Signed-off-by: Frank Li <Frank.Li@freescale.com>
Signed-off-by: Robin Gong <b38343@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-imx: spi_imx_remove: do not disable disabled clocks

Currently, at module removal, one gets the following warnings:
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:780 clk_disable+0x18/0x24()
Modules linked in: spi_imx(-) [last unloaded: ev76c560]
CPU: 1 PID: 16337 Comm: rmmod Tainted: G W 3.10.17-80548-g90191eb-dirty #33
[<80013b4c>] (unwind_backtrace+0x0/0xf8) from [<800115dc>] (show_stack+0x10/0x14)
[<800115dc>] (show_stack+0x10/0x14) from [<800257b8>] (warn_slowpath_common+0x4c/0x68)
[<800257b8>] (warn_slowpath_common+0x4c/0x68) from [<800257f0>] (warn_slowpath_null+0x1c/0x24)
[<800257f0>] (warn_slowpath_null+0x1c/0x24) from [<803f60ec>] (clk_disable+0x18/0x24)
[<803f60ec>] (clk_disable+0x18/0x24) from [<7f02c9cc>] (spi_imx_remove+0x54/0x9c [spi_imx])
[<7f02c9cc>] (spi_imx_remove+0x54/0x9c [spi_imx]) from [<8025868c>] (platform_drv_remove+0x18/0x1c)
[<8025868c>] (platform_drv_remove+0x18/0x1c) from [<80256f60>] (__device_release_driver+0x70/0xcc)
[<80256f60>] (__device_release_driver+0x70/0xcc) from [<80257770>] (driver_detach+0xcc/0xd0)
[<80257770>] (driver_detach+0xcc/0xd0) from [<80256d90>] (bus_remove_driver+0x7c/0xc0)
[<80256d90>] (bus_remove_driver+0x7c/0xc0) from [<80068668>] (SyS_delete_module+0x144/0x1f8)
[<80068668>] (SyS_delete_module+0x144/0x1f8) from [<8000e080>] (ret_fast_syscall+0x0/0x30)
---[ end trace 1f5df9ad54996300 ]---
------------[ cut here ]------------
WARNING: at drivers/clk/clk.c:780 clk_disable+0x18/0x24()
Modules linked in: spi_imx(-) [last unloaded: ev76c560]
CPU: 1 PID: 16337 Comm: rmmod Tainted: G W 3.10.17-80548-g90191eb-dirty #33
[<80013b4c>] (unwind_backtrace+0x0/0xf8) from [<800115dc>] (show_stack+0x10/0x14)
[<800115dc>] (show_stack+0x10/0x14) from [<800257b8>] (warn_slowpath_common+0x4c/0x68)
[<800257b8>] (warn_slowpath_common+0x4c/0x68) from [<800257f0>] (warn_slowpath_null+0x1c/0x24)
[<800257f0>] (warn_slowpath_null+0x1c/0x24) from [<803f60ec>] (clk_disable+0x18/0x24)
[<803f60ec>] (clk_disable+0x18/0x24) from [<7f02c9e8>] (spi_imx_remove+0x70/0x9c [spi_imx])
[<7f02c9e8>] (spi_imx_remove+0x70/0x9c [spi_imx]) from [<8025868c>] (platform_drv_remove+0x18/0x1c)
[<8025868c>] (platform_drv_remove+0x18/0x1c) from [<80256f60>] (__device_release_driver+0x70/0xcc)
[<80256f60>] (__device_release_driver+0x70/0xcc) from [<80257770>] (driver_detach+0xcc/0xd0)
[<80257770>] (driver_detach+0xcc/0xd0) from [<80256d90>] (bus_remove_driver+0x7c/0xc0)
[<80256d90>] (bus_remove_driver+0x7c/0xc0) from [<80068668>] (SyS_delete_module+0x144/0x1f8)
[<80068668>] (SyS_delete_module+0x144/0x1f8) from [<8000e080>] (ret_fast_syscall+0x0/0x30)
---[ end trace 1f5df9ad54996301 ]---

Since commit 9e556dcc55774c9a1032f32baa0e5cfafede8b70, "spi: spi-imx: only
enable the clocks when we start to transfer a message", clocks are always
disabled except when transmitting messages. There is thus no need to
disable them at module removal.

Fixes: 9e556dcc55774 (spi: spi-imx: only enable the clocks when we start to transfer a message)
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Acked-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org

spi/imx: Use dev_name() for request_irq() to distinguish SPIs

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-imx: Propagate the real error code on platform_get_irq() failure

No need to return a 'fake' return value on platform_get_irq() failure.

Just return the error code itself instead.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: Use reinit_completion at appropriate places

Calling init_completion() once is enough.
For the rest of the iterations, call reinit_completion() instead.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: delete non-required instances of include <linux/init.h>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-imx: Fix out-of-order CS/SCLK operation at low speeds

Problem:
--------
The problem this patch addresses has the following assumptions about the
SPI bus setup:
- The hardware used to find this is Freescale i.MX537 @ 1200MHz
- The SPI SCLK operate at very low speed, less than 200 kHz
- There are two SPI devices attached to the bus
- Each device uses different GPIO for chipselect
- Each device requires different SCLK signal polarity

The observation of the SCLK and GPIO chipselect lines with a logic analyzer
shows, that the SCLK polarity change does sometimes happen after the GPIO
chipselect is asserted. The SPI slave device reacts on that by counting the
SCLK polarity change as a clock pulse, which disrupts the communication with
the SPI slave device.

Explanation:
------------
We found an interesting correlation, that the maximum delay between the write
into the ECSPIx_CONFIGREG register and the change of SCLK polarity at each
SCLK frequency of 10 kHz, 20 kHz, 50 kHz and 100 kHz is 100 uS, 50 uS, 20 uS
and 10 uS respectively. This lead us to a theory, that at SCLK frequency of
1 Hz, the delay would be 1 S. Therefore, the time it takes for the write to
ECSPIx_CONFIGREG to take effect in the hardware is up to the duration of 1
tick of the SCLK clock.

During this delay period, if the SCLK frequency is too low, the execution of
the spi-imx.c driver can advance so much, that the GPIO chipselect will be
asserted. The GPIO chipselect is asserted almost immediatelly.

Solution:
---------
The solution this patch presents is simple. We calculate the resulting SCLK
clock first by dividing the ECSPI block clock by both dividers that are to be
programmed into the configuration register. Based on the resulting SCLK clock,
we derive the delay it will take for the changes to get really applied. We are
extra careful here so we delay twice as long as we should. Note that the patch
does not create additional overhead at high speeds as the delay will likely be
close to zero there.

Signed-off-by: Marek Vasut <marex@denx.de>
To: linux-spi@vger.kernel.org
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Huang Shijie <b32955@freescale.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-imx: only enable the clocks when we start to transfer a message

Current code keeps the clocks enabled all the time, it wastes the power
when there is no operaiton on the spi controller.

In order to save the power, this patch adds the two hooks:
spi_imx_prepare_message: enable the clocks for this message
spi_imx_unprepare_message: disable the clocks.

This patch also disables the clocks in the end of the probe.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: bitbang: Let spi_bitbang_start() take a reference to master

Many drivers that use bitbang library have a leak on probe error paths.
This is because once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory.

Fix this issue by moving the code taking a reference to master to
spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on
success. With this change, the caller is responsible for calling
spi_bitbang_stop() to decrement the reference and spi_master_put() as
counterpart of spi_alloc_master() to prevent a memory leak.

So now we have below patten for drivers using bitbang library:

probe:
spi_alloc_master -> Init reference count to 1
spi_bitbang_start -> Increment reference count
remove:
spi_bitbang_stop -> Decrement reference count
spi_master_put -> Decrement reference count (reference count reaches 0)

Fixup all users accordingly.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Suggested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: bitbang: Let spi_bitbang_start() take a reference to master

Many drivers that use bitbang library have a leak on probe error paths.
This is because once a spi_master_get() call succeeds, we need an additional
spi_master_put() call to free the memory.

Fix this issue by moving the code taking a reference to master to
spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on
success. With this change, the caller is responsible for calling
spi_bitbang_stop() to decrement the reference and spi_master_put() as
counterpart of spi_alloc_master() to prevent a memory leak.

So now we have below patten for drivers using bitbang library:

probe:
spi_alloc_master -> Init reference count to 1
spi_bitbang_start -> Increment reference count
remove:
spi_bitbang_stop -> Decrement reference count
spi_master_put -> Decrement reference count (reference count reaches 0)

Fixup all users accordingly.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Suggested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/imx: expose module alias for loading from device-tree

Enable auto loading by udev when spi-imx is compiled as a module.

Signed-off-by: Niels de Vos <ndevos@redhat.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-imx: Check the return value from clk_prepare_enable()

clk_prepare_enable() may fail, so let's check its return value and propagate it
in the case of error.

While at it, fix the order of clk_disable_unprepare calls: clk_ipg should be
disabled first, followed by clk_per.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-imx: Use devm functions

Using devm functions can make the code smaller and cleaner.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-imx: Fix compilation error

Fix compilation error due to a typo introduced by commit 24778be20f
("spi: convert drivers to use bits_per_word_mask"). Without this patch
we get the following build errors:

drivers/spi/spi-imx.c: In function ‘spi_imx_setupxfer’:
drivers/spi/spi-imx.c:703:2: warning: no return statement in function returning non-void [-Wreturn-type]
drivers/spi/spi-imx.c: At top level:
drivers/spi/spi-imx.c:705:9: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘->’ token
drivers/spi/spi-imx.c:707:2: error: expected identifier or ‘(’ before ‘return’
drivers/spi/spi-imx.c:708:1: error: expected identifier or ‘(’ before ‘}’ token

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: convert drivers to use bits_per_word_mask

Fill in the recently added spi_master.bits_per_word_mask field in as
many drivers as possible. Make related cleanups, such as removing any
redundant error-checking, or empty setup callbacks.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: spi-imx: Let device core handle pinctrl

Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.

So remove devm_pinctrl_get_select_default() from the driver.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d0631001288a5974afc0b2a5f568bcdecb4d
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/imx: Add MODULE_ALIAS()

Add an entry for MODULE_ALIAS().

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: Remove HOTPLUG section attributes

CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.

Bill Pemberton has done most of the legwork on this series. I've used
his script to purge the attributes from the drivers/gpio tree.

Reported-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: set the inactive state of the clock according to the clock polarity

There are SPI devices which need a SPI clock with active low polarity and
high inactive state.

Add the setting of the inactive state ECSPIx_CONFIGREG:SCLK CTL
according to the clock polarity ECSPIx_CONFIGREG:SCLK POL:

DT without "spi-cpol" = 0 = clock active high polarity = inactive state low
DT with "spi-cpol" = 1 = clock active low polarity = inactive state high

Signed-off-by: Knut Wohlrab <knut.wohlrab@de.bosch.com>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

ARM: imx: move platform_data definitions

Platform data for device drivers should be defined in
include/linux/platform_data/*.h, not in the architecture
and platform specific directories.

This moves such data out of the imx include directories

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Sascha Hauer <kernel@pengutronix.de>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Dan Williams <djbw@fb.com>
Cc: "Ben Dooks (embedded platforms)" <ben-linux@fluff.org>
Cc: "Wolfram Sang (embedded platforms)" <w.sang@pengutronix.de>
Cc: Chris Ball <cjb@laptop.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Javier Martin <javier.martin@vista-silicon.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

spi/imx: make spi_imx_data.devtype_data member point to const data

This prepares *of_device_id.data becoming const. Without this change the
following warning would occur:

drivers/spi/spi-imx.c: In function spi_imx_probe:
drivers/spi/spi-imx.c:814:24: warning: assignment discards const qualifier from pointer target type [enabled by default]

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

spi/imx: use gpio_is_valid to determine if a gpio is valid

Use gpio_is_valid() to replace "gpio >= 0" or "gpio < 0".

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Hui Wang <jason77.wang@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/imx: remove redundant config.speed_hz setting

The config.speed_hz is just setted at the two lines ahead of it,
obviously we don't need to copy the code to set the config.speed_hz
again. Remove it for a cleanup.

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Hui Wang <jason77.wang@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi/imx: adopt pinctrl support

Cc: spi-devel-general@lists.sourceforge.net
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>

spi i.MX: do not depend on grouped clocks

the current i.MX clock support groups together unrelated clocks
to a single clock which is then used by the driver. This can't
be accomplished with the generic clock framework so we instead
request the individual clocks in the driver. For i.MX there are
generally three different clocks:

ipg: bus clock (needed to access registers)
ahb: dma relevant clock, sometimes referred to as hclk in the datasheet
per: bit clock, pixel clock

This patch changes the driver to request the individual clocks.
Currently all clk_get will get the same clock until the SoCs
are converted to the generic clock framework

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

spi/imx: prevent NULL pointer dereference in spi_imx_probe()

When no platform_data is present and either 'spi-num-chipselects' is
not defined in the DT or 'cs-gpios' has less entries than
'spi-num-chipselects' specifies, the NULL platform_data pointer is
being dereferenced.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: mark base member in spi_imx_data as __iomem

This fixes 36 sparse warnings like:

drivers/spi/spi-imx.c:143:1: warning: incorrect type in argument 1 (different address spaces)
drivers/spi/spi-imx.c:143:1: expected void const volatile [noderef] <asn:2>*<noident>
drivers/spi/spi-imx.c:143:1: got void *

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: simplify error handling to free gpios

Simplify the error handling by moving the code to free gpios in one place.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivercore: Add helper macro for platform_driver boilerplate

For simple modules that contain a single platform_driver without any
additional setup code then ends up being a block of duplicated
boilerplate. This patch adds a new macro, module_platform_driver(),
which replaces the module_init()/module_exit() registrations with
template functions.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: Magnus Damm <magnus.damm@gmail.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>

spi/imx: Fix spi-imx when the hardware SPI chipselects are used

commit 22a85e4cd51 (spi/imx: add device tree probe support) broke spi-imx usage
when the SPI chipselect is the one internal to the controller.

On a mx31pdk board the following error is seen:

Registering mxc_nand as whole device
------------[ cut here ]------------
WARNING: at drivers/gpio/gpiolib.c:101 gpio_ensure_requested+0x4c/0xf4()
autorequest GPIO-0
Modules linked in:
[<c0014410>] (unwind_backtrace+0x0/0xf4) from [<c0025754>] (warn_slowpath_common+0x4c/0x64)
[<c0025754>] (warn_slowpath_common+0x4c/0x64) from [<c0025800>] (warn_slowpath_fmt+0x30/0x40)
[<c0025800>] (warn_slowpath_fmt+0x30/0x40) from [<c0198688>] (gpio_ensure_requested+0x4c/0xf4)
[<c0198688>] (gpio_ensure_requested+0x4c/0xf4) from [<c01988c8>] (gpio_direction_output+0xa0/0x138)
[<c01988c8>] (gpio_direction_output+0xa0/0x138) from [<c01ed198>] (spi_imx_setup+0x38/0x4c)
[<c01ed198>] (spi_imx_setup+0x38/0x4c) from [<c01eb5d0>] (spi_setup+0x38/0x50)
[<c01eb5d0>] (spi_setup+0x38/0x50) from [<c01eb85c>] (spi_add_device+0x94/0x124)
[<c01eb85c>] (spi_add_device+0x94/0x124) from [<c01eb960>] (spi_new_device+0x74/0xac)
[<c01eb960>] (spi_new_device+0x74/0xac) from [<c01eb9b8>] (spi_match_master_to_boardinfo+0x20/0x40)
[<c01eb9b8>] (spi_match_master_to_boardinfo+0x20/0x40) from [<c01eba88>] (spi_register_master+0xb0/0x104)
[<c01eba88>] (spi_register_master+0xb0/0x104) from [<c01ec0b4>] (spi_bitbang_start+0x104/0x17c)
[<c01ec0b4>] (spi_bitbang_start+0x104/0x17c) from [<c02c2c4c>] (spi_imx_probe+0x2fc/0x404)
[<c02c2c4c>] (spi_imx_probe+0x2fc/0x404) from [<c01c2498>] (platform_drv_probe+0x18/0x1c)
[<c01c2498>] (platform_drv_probe+0x18/0x1c) from [<c01c1058>] (driver_probe_device+0x78/0x174)
[<c01c1058>] (driver_probe_device+0x78/0x174) from [<c01c11e0>] (__driver_attach+0x8c/0x90)
[<c01c11e0>] (__driver_attach+0x8c/0x90) from [<c01c0860>] (bus_for_each_dev+0x60/0x8c)
[<c01c0860>] (bus_for_each_dev+0x60/0x8c) from [<c01c0088>] (bus_add_driver+0xa0/0x288)
[<c01c0088>] (bus_add_driver+0xa0/0x288) from [<c01c179c>] (driver_register+0x78/0x18c)
[<c01c179c>] (driver_register+0x78/0x18c) from [<c0008490>] (do_one_initcall+0x34/0x178)
[<c0008490>] (do_one_initcall+0x34/0x178) from [<c03a5204>] (kernel_init+0x74/0x118)
[<c03a5204>] (kernel_init+0x74/0x118) from [<c000f65c>] (kernel_thread_exit+0x0/0x8)
---[ end trace 759f924b30fd5a44 ]---

Fix this issue by using the original chip select logic and make spi-imx to work again.

Tested on a mx31pdk that uses the hardware SPI chipselect pins and also
on a mx27pdk that uses GPIO as SPI chipselect.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: add device tree probe support

It adds device tree probe support for spi-imx driver.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: copy gpio number passed by platform data into driver private data

It copies gpio number passed via platform data embedded pointer into
driver private data, so that we do not need to refer to this embedded
pointer passed by platform data after probe function exits.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: use soc name in spi device type naming scheme

Software defined version number is not stable enough to be used
in device type naming scheme. The patch changes it to use implicit
soc name for spi device type definition. In this way, we can easily
align the naming scheme with device tree binding, which comes later.

It removes fifosize from spi_imx_data and adds devtype there, so that
fifosize can be set in an inline function according to devtype.
Also, cpu_is_mx can be replaced by inline functions checking devtype.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: merge type SPI_IMX_VER_0_7 into SPI_IMX_VER_0_4

The only difference between SPI_IMX_VER_0_7 and SPI_IMX_VER_0_4 is
.config function. The patch uses cpu_is_mx35 (to be removed) as the
temporary solution to consolidate functions spi_imx0_4_config and
spi_imx0_7_config into mx31_config. As a result, type SPI_IMX_VER_0_7
can be merged into SPI_IMX_VER_0_4.

It also renames function spi_imx0_4_reset to mx31_reset to keep
consistency with other function naming.

A couple of redundant macros, MX3_CSPISTAT and MX3_CSPISTAT_RR,
together with the useless type SPI_IMX_VER_0_5 also get cleaned up.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: do not use spi_imx2_3 to name SPI_IMX_VER_2_3 function and macro

It's confusing to use spi_imx2_3 to name SPI_IMX_VER_2_3 function
and macro, as it easily make people think of imx2 and imx3. It's
better to use specific soc name just like what other SPI_IMX_VER
do. For SPI_IMX_VER_2_3 case, it will be mx51. To distinguish it
from CSPI on mx51, mx51_ecspi might be a good choice.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: use mx21 to name SPI_IMX_VER_0_0 function and macro

SPI_IMX_VER_0_0 covers i.mx21 and i.mx27. It makes more sense to
use mx21 rather than mx27 to name SPI_IMX_VER_0_0 function and
macro, since i.mx21 comes out ealier than i.mx27.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/imx: do not make copy of spi_imx_devtype_data

spi_imx_devtype_data has already been driver private data. There is
really no need to make a copy in spi_imx_data. Instead, a reference
pointer works perfectly fine.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: reorganize drivers

Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.

This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.

v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
be the predominant pattern for subsystem prefixes.
- Clean up filenames in Kconfig and header comment blocks

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>