spi: sun6i: switch to use modern name

Change legacy name master to modern name host or controller.

No functional changed.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://msgid.link/r/20231128093031.3707034-8-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: fix race between DMA RX transfer completion and RX FIFO drain

Previously the transfer complete IRQ immediately drained to RX FIFO to
read any data remaining in FIFO to the RX buffer. This behaviour is
correct when dealing with SPI in interrupt mode. However in DMA mode the
transfer complete interrupt still fires as soon as all bytes to be
transferred have been stored in the FIFO. At that point data in the FIFO
still needs to be picked up by the DMA engine. Thus the drain procedure
and DMA engine end up racing to read from RX FIFO, corrupting any data
read. Additionally the RX buffer pointer is never adjusted according to
DMA progress in DMA mode, thus calling the RX FIFO drain procedure in DMA
mode is a bug.
Fix corruptions in DMA RX mode by draining RX FIFO only in interrupt mode.
Also wait for completion of RX DMA when in DMA mode before returning to
ensure all data has been copied to the supplied memory buffer.

Signed-off-by: Tobias Schramm <t.schramm@manjaro.org>
Link: https://lore.kernel.org/r/20230827152558.5368-3-t.schramm@manjaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: reduce DMA RX transfer width to single byte

Through empirical testing it has been determined that sometimes RX SPI
transfers with DMA enabled return corrupted data. This is down to single
or even multiple bytes lost during DMA transfer from SPI peripheral to
memory. It seems the RX FIFO within the SPI peripheral can become
confused when performing bus read accesses wider than a single byte to it
during an active SPI transfer.

This patch reduces the width of individual DMA read accesses to the
RX FIFO to a single byte to mitigate that issue.

Signed-off-by: Tobias Schramm <t.schramm@manjaro.org>
Link: https://lore.kernel.org/r/20230827152558.5368-2-t.schramm@manjaro.org
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: sun6i: add dual and quad SPI modes support for R329/D1/R528/T113s

Listed SoCs have SPI controllers that can operate in dual or quad modes.
This patch adds dual/quad mode bits for spi_master on these SoCS.

Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com>
Link: https://lore.kernel.org/r/20230624131632.2972546-3-bigunclemax@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: add quirk for dual and quad SPI modes support

New Allwinner's SPI controllers can support dual and quad SPI modes.
To enable one of these modes, we should set the corresponding bit in
the SUN6I_BURST_CTL_CNT_REG register. DRM (28 bits) for dual mode and
Quad_EN (29 bits) for quad transmission.

Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com>
Link: https://lore.kernel.org/r/20230624131632.2972546-2-bigunclemax@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: Use the new helper to derive the xfer timeout value

A helper was recently added to the core to factorize common code between
drivers, like the amount of time a driver should wait for a transfer to
happen.

It is of course possible to use a default value (like eg. 1s) but it is
way stronger to adapt this amount of time to the transfer. Indeed, long
transfers (eg. 4MiB) on a slow single-spi bus might take more than the
usual second of timeout and prevent lengthy transfers.

The core helper was heavily inspired by the logic applied in this
driver, the only difference being the minimum amount of time which was
enlarged from 0.1s to 0.5s.

Use this helper instead of open-coding it.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jernej Škrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/Message-Id: <20230622090634.3411468-4-miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: add support for R329/D1/R528/T113s SPI controllers

These SoCs has two SPI controllers. One of it is quite similar to previous
ones, but with internal clock divider removed; the other added MIPI DBI
Type-C offload based on the first one.

Add basical support for these controllers. As we're not going to
support the DBI functionality now, just implement the two kinds of
controllers as the same.

Co-developed-by: Icenowy Zheng <icenowy@aosc.io
Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com
Reviewed-by: Andre Przywara <andre.przywara@arm.com
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com
Link: https://lore.kernel.org/r/20230510081121.3463710-5-bigunclemax@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org

spi: sun6i: add quirk for in-controller clock divider

Previously SPI controllers in Allwinner SoCs has a clock divider inside.
However now the clock divider is removed and to set the transfer clock
rate it's only needed to set the SPI module clock to the target value
and configure a proper work mode.

According to the datasheet there are three work modes:

| SPI Sample Mode | SDM(bit13) | SDC(bit11) | Run Clock |
|-------------------------|------------|------------|-----------|
| normal sample | 1 | 0 | <= 24 MHz |
| delay half cycle sample | 0 | 0 | <= 40 MHz |
| delay one cycle sample | 0 | 1 | >= 80 MHz |

Add a quirk for this kind of SPI controllers.

Co-developed-by: Icenowy Zheng <icenowy@aosc.io
Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com
Reviewed-by: Andre Przywara <andre.przywara@arm.com
Link: https://lore.kernel.org/r/20230510081121.3463710-4-bigunclemax@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org

spi: sun6i: change OF match data to a struct

As we're adding more properties to the OF match data, convert it to a
struct now.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io
Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com
Reviewed-by: Samuel Holland <samuel@sholland.org
Reviewed-by: Andre Przywara <andre.przywara@arm.com
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com
Link: https://lore.kernel.org/r/20230510081121.3463710-3-bigunclemax@gmail.com
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: sun6i: 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>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Link: https://lore.kernel.org/r/20230303172041.2103336-76-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: Fix chipselect/clock bug

The current sun6i SPI implementation initializes the transfer too early,
resulting in SCK going high before the transfer. When using an additional
(gpio) chipselect with sun6i, the chipselect is asserted at a time when
clock is high, making the SPI transfer fail.

This is due to SUN6I_GBL_CTL_BUS_ENABLE being written into
SUN6I_GBL_CTL_REG at an early stage. Moving that to the transfer
function, hence, right before the transfer starts, mitigates that
problem.

Fixes: 3558fe900e8af (spi: sunxi: Add Allwinner A31 SPI controller driver)
Signed-off-by: Mirko Vogt <mirko-dev|linux@nanl.de>
Signed-off-by: Ralf Schlatterbeck <rsc@runtux.com>
Link: https://lore.kernel.org/r/20210614144507.y3udezjfbko7eavv@runtux.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: enable autosuspend feature

If SPI is used for periodic polling any sensor, significant delays
sometimes appear. Switching on module clocks during resume lead to delays.
Enabling autosuspend mode causes the controller to not suspend between
SPI transfers and the delays disappear.

The commit also remove unnecessary call to pm_runtime_idle() used
to explicit put device to suspended state. Without pm_runtime_idle() PM
core will put device in the suspended state just after probe() returns.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20201019150343.2520-1-akochetkov@lintech.ru
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: implement DMA-based transfer mode

DMA-based transfer will be enabled if data length is larger than FIFO size
(64 bytes for A64). This greatly reduce number of interrupts for
transferring data.

For smaller data size PIO mode will be used. In PIO mode whole buffer will
be loaded into FIFO.

If driver failed to request DMA channels then it fallback for PIO mode.

Tested on SOPINE (https://www.pine64.org/sopine/)

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20201022075221.23332-1-akochetkov@lintech.ru
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_transfer_one(): enable RF_RDY interrupt only if needed

In sun6i_spi_transfer_one() the RX FIFO Ready (SUN6I_INT_CTL_RF_RDY) is
unconditionally enabled.

A RX interrupt is only needed, if more data than fits into the FIFO is going to
be received during this transfer. As the RX-FIFO is drained during transfer
complete interrupt, enable the RX FIFO Ready interrupt only if the data doesn't
fit into the FIFO.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-11-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_transfer_one(): collate write to Interrupt Control Register

In sun6i_spi_transfer_one() the Interrupt Control Register is written three
times. This patch collates the three writes into one.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-10-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_fill_fifo(): remove not needed length argument

The function sun6i_spi_fill_fifo() is called with a length argument of
"sspi->fifo_depth" and "SUN6I_FIFO_DEPTH".

The driver reads the number of free bytes in the FIFO from the hardware and
uses the length argument to limit this value. This is not needed as the number
of free bytes in the FIFO is always less or equal the depth of the FIFO.

This patch removes the length argument and check.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-9-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_drain_fifo(): remove not needed length argument

The function sun6i_spi_drain_fifo() is called with a length argument of
"sspi->fifo_depth" and "SUN6I_FIFO_DEPTH".

The driver reads the number of available bytes to read from the FIFO from the
hardware and uses the length argument to limit this value. This is not needed
as the FIFO can contain only the fifo depth number of bytes.

This patch removes the length argument and check.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-8-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_drain_fifo(): introduce sun6i_spi_get_rx_fifo_count() and make use of it

This patch introduces the function sun6i_spi_get_rx_fifo_count(), similar to
the existing sun6i_spi_get_tx_fifo_count(), to make the sun6i_spi_drain_fifo()
function a bit easier to read.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-7-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_get_tx_fifo_count: Convert manual shift+mask to FIELD_GET()

This patch converts the manual shift+mask in sun6i_spi_get_tx_fifo_count() to
make use of FIELD_GET()

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200706143443.9855-6-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_transfer_one(): remove not needed masking of transfer length

In sun6i_spi_transfer_one() the driver ensures that the length of the transfer
is smaller or equal to SUN6I_MAX_XFER_SIZE. This means the masking of the
length to SUN6I_MAX_XFER_SIZE can be skipped when writing the transfer length
into the registers.

This patch removes the useless masking of the transfer length to
SUN6I_MAX_XFER_SIZE.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-5-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_transfer_one(): remove useless goto

This patch removes an useless goto at the end of
sun6i_spi_transfer_one().

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-4-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_transfer_one(): report effectivly used speed_hz of transfer

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>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-3-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sun6i: sun6i_spi_transfer_one(): fix setting of clock rate

A SPI transfer defines the _maximum_ speed of the SPI transfer. However the
driver doesn't take into account that the clock divider is always rounded down
(due to integer arithmetics). This results in a too high clock rate for the SPI
transfer.

E.g.: with a mclk_rate of 24 MHz and a SPI transfer speed of 10 MHz, the
original code calculates a reg of "0", which results in a effective divider of
"2" and a 12 MHz clock for the SPI transfer.

This patch fixes the issue by using DIV_ROUND_UP() instead of a plain
integer division.

While there simplify the divider calculation for the CDR1 case, use
order_base_2() instead of two ilog2() calculations.

Fixes: 3558fe900e8a ("spi: sunxi: Add Allwinner A31 SPI controller driver")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200706143443.9855-2-mkl@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: Add support for GPIO chip select lines

Set use_gpio_descriptors as true to support using generic GPIO
lines for the chip select.

Signed-off-by: Alistair Francis <alistair@alistair23.me>
Link: https://lore.kernel.org/r/20200511045330.690507-1-alistair@alistair23.me
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: use devm_platform_ioremap_resource() to simplify code

Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-31-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Remove dev_err() usage after platform_get_irq()

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-42-swboyd@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi: sun6i: disable/unprepare clocks on remove

sun6i_spi_probe() uses sun6i_spi_runtime_resume() to prepare/enable
clocks, so sun6i_spi_remove() should use sun6i_spi_runtime_suspend() to
disable/unprepare them if we're not suspended.
Replacing pm_runtime_disable() by pm_runtime_force_suspend() will ensure
that sun6i_spi_runtime_suspend() is called if needed.

Found by Linux Driver Verification project (linuxtesting.org).

Fixes: 3558fe900e8af (spi: sunxi: Add Allwinner A31 SPI controller driver)
Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: explicitly request exclusive reset control

Commit a53e35db70d1 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.

No functional changes.

Cc: Mark Brown <broonie@kernel.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: linux-spi@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: update max transfer size reported

The spi-sun6i driver have already got the ability to do large transfers.
However, the max transfer size reported is still fifo depth - 1.

Update the max transfer size reported to the max value possible.

Reported-by: Martin Ayotte <martinayotte@gmail.com>
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: Allow transfers larger than FIFO size

The spi-sun6i driver have the same problem that spi-sun4i used to have
-- SPI transfers are limited to one FIFO depth.

This commit fixes this problem in the same way it's fixed in spi-sun4i.
See commit 196737912da5 ("spi: sun4i: Allow transfers larger than FIFO size")
for more information.

The sun6i SPI controllers features changeable interrupt trigger level, but I
set it to 3/4 of fifo depth, as same as the the sun4i SPI controllers.

Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun6i: Support Allwinner H3 SPI controller

H3 has two SPI controllers. The size of the buffer is 64 * 8.
(8 bit transfer by 64 entry FIFO)
A31 has four controllers. The size of the buffer is 128 * 8.
(8 bit transfer by 128 entry FIFO)

Register maps are sharable, so sun6i SPI driver is reusable with
device configuration.

Use the variable, 'fifo_depth' instead of fixed value to support both SPI
controllers.

Signed-off-by: Milo Kim <woogyom.kim@gmail.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sunxi: set maximum and minimum speed of SPI master

The speed limits are unset in the sun4i and sun6i SPI drivers.

The maximum speed of SPI master is used when maximum speed of SPI slave
is not specified. Also the __spi_validate function should check that
transfer speeds do not exceed the master limits.

The user manual for A10 and A31 specifies maximum
speed of the SPI clock as 100MHz and minimum as 3kHz.

Setting the SPI clock to out-of-spec values can lock up the SoC.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
--
v2:
new patch
v3:
fix constant style
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sunxi: fix transfer timeout

The trasfer timeout is fixed at 1000 ms. Reading a 4Mbyte flash over
1MHz SPI bus takes way longer than that. Calculate the timeout from the
actual time the transfer is supposed to take and multiply by 2 for good
measure.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: sunxi: expose maximum transfer size limit

The sun4i spi hardware can trasfer at most 63 bytes of data without DMA
support so report the limitation. Same for sun6i.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sun4i: allow transfers to set transmission speed

Allow transfers to set the transmission speed rather than using the
device max_speed_hz value. The SPI core makes sure that the speed_hz
value is always set on the transfer.

Signed-off-by: Marcus Weseloh <mweseloh42@gmail.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: Remove unneeded include of linux/workqueue.h

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

spi: sun6i: Set bits_per_word_mask to only support 8 bits word length

This controller only supports 8 bits word length.
Set bits_per_word_mask so spi core will reject transfers that attempt to use
an unsupported bits_per_word value.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sun6i: Fix define for SUN6I_TFR_CTL_CS_MASK

Current code in sun6i_spi_set_cs() actually clears CPHA and CPOL bits which is
obvious wrong. The define for SUN6I_TFR_CTL_CS_MASK is wrong. Fix it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sunxi: Add Allwinner A31 SPI controller driver

The Allwinner A31 has a new SPI controller IP compared to the older Allwinner
SoCs.

It supports DMA, but the driver only does PIO for now, and DMA will be
supported eventually.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>