spi: sh-msiof: avoid integer overflow in constants

cppcheck rightfully warned:

drivers/spi/spi-sh-msiof.c:792:28: warning: Signed integer overflow for expression '7<<29'. [integerOverflow]
sh_msiof_write(p, SIFCTR, SIFCTR_TFWM_1 | SIFCTR_RFWM_1);

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://msgid.link/r/20240130094053.10672-1-wsa+renesas@sang-engineering.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Enforce fixed DTDL for R-Car H3

Documentation says only DTDL of 200 is allowed for this SoC.

Fixes: 4286db8456f4 ("spi: sh-msiof: Add R-Car Gen 2 and 3 fallback bindings")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://msgid.link/r/20231212081239.14254-1-wsa+renesas@sang-engineering.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: 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>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230818093154.1183529-20-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: sh-msiof: Mark OF related data as maybe unused

The driver can be compile tested with !CONFIG_OF making certain data
unused:

drivers/spi/spi-sh-msiof.c:1076:34: error: ‘sh_msiof_match’ defined but not used [-Werror=unused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230310222857.315629-14-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Remove casts to drop constness

Now the chip select APIs take const pointers, there is no longer a need
to cast away constness.

Fixes: 9e264f3f85a56cc1 ("spi: Replace all spi->chip_select and spi->cs_gpiod references with function call")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/bc14c7c75f8d63c5c11f61f80daaa53b12bb15fb.1678704562.git.geert+renesas@glider.be
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: sh-msiof: 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/20230303172041.2103336-65-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: add generic Gen4 binding

No further changes in this generation discovered yet.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220824094327.33685-3-wsa+renesas@sang-engineering.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: drop unneeded MODULE_ALIAS

The MODULE_DEVICE_TABLE already creates proper alias for platform
driver. Having another MODULE_ALIAS causes the alias to be duplicated.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210916164423.134603-2-krzysztof.kozlowski@canonical.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sh-msiof: : use proper DMAENGINE API for termination

dmaengine_terminate_all() is deprecated in favor of explicitly saying if
it should be sync or async. Here, we want dmaengine_terminate_sync()
because there is no other synchronization code in the driver to handle
an async case.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210623095843.3228-3-wsa+renesas@sang-engineering.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fill in controller speed limits

Fill in the controller speed limits, so the SPI core can use them for
validating SPI transfers, and adjust or reject transfers when needed.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20210113101916.1147695-3-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fill in spi_transfer.effective_speed_hz

Fill in the effective bit rate used for transfers, so the SPI core can
calculate instead of estimate delays.

Restore "reverse Christmas tree" order of local variables while adding
new variables.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20210113101916.1147695-2-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sh-msiof: Fix checkpatch error Complex macros should use ()

Fixed checkpatch error "Macros with complex values should be enclosed
in parentheses"

Signed-off-by: Aishwarya R <raishwar@visteon.com>
Link: https://lore.kernel.org/r/20200406155301.21768-1-raishwar@visteon.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Do not redefine STR while compile testing

STR is a well-known stringify macro so it should be avoided in drivers
to avoid warnings like this (MIPS architecture while compile testing):

drivers/spi/spi-sh-msiof.c:76:0: warning: "STR" redefined
#define STR 0x40 /* Status Register */
arch/mips/include/asm/mipsregs.h:30:0: note: this is the location of the previous definition
#define STR(x) __STR(x)

To maintain consistency between all register names add a SI prefix to
all of them. This also matches register names in datasheet.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200108194319.3171-1-krzk@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Convert to generic unused native cs handling.

Currently the MSIOF SPI driver uses custom code to handle the unused
native chip select with GPIO chip selects.
Convert the driver to use the new generic handling in the SPI core.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200102133822.29346-3-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use devm_platform_ioremap_resource() helper

Use the devm_platform_ioremap_resource() helper instead of open-coding
the same operation.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20190807085213.24666-1-geert+renesas@glider.be
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>

spi: sh-msiof: Reduce delays in sh_msiof_modify_ctr_wait()

While the Hardware User Manual does not document the maximum time needed
for modifying bits in the MSIOF Control Register, experiments on R-Car
Gen2/Gen3 and SH-Mobile AG5 revealed the following typical modification
times for the various bits:
- CTR.TXE and CTR.RXE: no delay,
- CTR.TSCKE: less than 10 ns,
- CTR.TFSE: up to a few hundred ns (depending on SPI transfer clock,
i.e. less for faster transfers).
There are no reasons to believe these figures are different for
SH-MobileR2 SoCs (SH7723/SH7724).

Hence the minimum busy-looping delay of 10 µs is excessive.
Reduce the delay per loop iteration from 10 to 1 us, and the maximum
delay from 1000 to 100 µs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Convert to use GPIO descriptors

Convert GPIO chip selects in the Renesas MSIOF SPI driver from legacy
GPIO numbers to GPIO descriptors.

Notes:
- The board file for the SH7724-based Ecovec24 development board now
registers a GPIO descriptor lookup, instead of passing a GPIO number
through controller_data,
- sh_msiof_get_cs_gpios() must release all GPIOs, else
spi_get_gpio_descs() cannot claim them during SPI controller
registration.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Add reset of registers before starting transfer

In accordance with hardware specification Ver 1.0, reset register
transmission / reception setting before transfer.

Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: Use readl_poll_timeout_atomic()]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use readl_poll_timeout_atomic() instead of open-coding

Replace the open-coded loop in sh_msiof_modify_ctr_wait() by a call to
the readl_poll_timeout_atomic() helper macro.

Suggested-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use BIT() and GENMASK()

Improve maintainability by converting the register bit, bitmask, and
bitfield definitions from hexadecimal constants to constructs using
BIT(), GENMASK(), or "val << shift".

Suggested-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Restrict bits per word to 8/16/24/32 on R-Car Gen2/3

While the MSIOF variants in older SuperH and SH/R-Mobile SoCs support
bits-per-word values in the full range 8..32, the variants present in
R-Car Gen2 and Gen3 SoCs are restricted to 8, 16, 24, or 32.

Obtain the value from family-specific sh_msiof_chipdata to fix this.

Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Replace spi_master by spi_controller

As of commit 8caab75fd2c2a926 ('spi: Generalize SPI "master" to
"controller"'), the old master-centric names are compatibility wrappers
for the new controller-centric names.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use DMA if possible

Currently, this driver only supports feature for DMA 32-bits.
In this case, only if the data length is divisible by 4 to use
DMA, otherwise PIO will be used. This patch will suggest use
the DMA 32-bits with 4bytes of words, then the remaining data
will be transmitted by PIO mode.

Signed-off-by: Hoan Nguyen An <na-hoan@jinso.co.jp>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: fix *info pointer in request_dma()

sh_msiof_spi_info *info struct pointer was initialized in the probe() function
no need to get back and keep consistency.

Signed-off-by: Hoan Nguyen An <na-hoan@jinso.co.jp>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Reduce the number of times write to and perform the transmission from FIFO

The current state of the spi-sh-msiof, in master transfer mode: if t-> bits_per_word <= 8,
if the data length is divisible by 4 ((len & 3) = 0), the length of each word will be 32 bits
In case of data length can not be divisible by 4 ((len & 3) != 0), always set each word to be
8 bits, this will increase the number of times that write to FIFO, increasing the number of
times it should be transmitted. Assume that the number of bytes of data length more than 64 bytes,
each transmission will write 64 times into the TFDR then transmit, a maximum one-time
transmission will transmit 64 bytes if each word is 8 bits long.

Switch to setting if t->bits_per_word <= 8, the word length will be 32 bits although the data
length is not divisible by 4, then if leftover, will transmit the balance and the length of each
words is 1 byte. The maximum each can transmit up to 64 x 4 (Data Size = 32 bits (4 bytes)) = 256 bytes.
TMDR2 : Bits 28 to 24 BITLEN1[4:0] Data Size (8 to 32 bits)
Bits 23 to 16 WDLEN1[7:0] Word Count (1 to 64 words)

Signed-off-by: Hoan Nguyen An <na-hoan@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spi-sh-msiof: simplify getting .driver_data

We should get 'driver_data' from 'struct device' directly. Going via
platform_device is an unneeded step back and forth.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: fix deferred probing

Since commit 9ec36cafe43b ("of/irq: do irq resolution in platform_get_irq")
platform_get_irq() can return -EPROBE_DEFER. However, the driver overrides
an error returned by that function with -ENOENT which breaks the deferred
probing. Propagate upstream an error code returned by platform_get_irq()
and remove the bogus "platform" from the error message, while at it...

Fixes: 9ec36cafe43b ("of/irq: do irq resolution in platform_get_irq")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fix handling of write value for SISTR register

This patch changes writing to the SISTR register according to the H/W
user's manual.

The TDREQ bit and RDREQ bits of SISTR are read-only, and must be written
their initial values of zero.

Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: reword]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: sh-msiof: Fix invalid SPI use during system suspend

If the SPI queue is running during system suspend, the system may lock
up.

Fix this by stopping/restarting the queue during system suspend/resume
by calling spi_master_suspend()/spi_master_resume() from the PM
callbacks. In-kernel users will receive an -ESHUTDOWN error while
system suspend/resume is in progress.

Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com>
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: Cleanup, reword]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: use SPDX identifier for Renesas drivers

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Make sure all DMA operations have completed

In case of a bi-directional transfer, receive DMA may complete in the
rcar-dmac driver before transmit DMA, due to scheduling latencies.
As the MSIOF driver waits for completion of the receive DMA only, it may
submit the next transmit DMA request before the previous one has
completed.

Make the driver more robust by waiting for the completion of both
receive and transmit DMA, when applicable.

Based on a patch in the BSP by Ryo Kataoka.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fix setting SIRMDR1.SYNCAC to match SITMDR1.SYNCAC

According to section 59.2.4 MSIOF Receive Mode Register 1 (SIRMDR1) in
the R-Car Gen3 datasheet Rev.1.00, the value of the SIRMDR1.SYNCAC bit
must match the value of the SITMDR1.SYNCAC bit. However,
sh_msiof_spi_setup() changes only the latter.

Fix this by updating the SIRMDR1 register like the SITMDR1 register,
taking into account register bits that exist in SITMDR1 only.

Reported-by: Renesas BSP team via Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: 7ff0b53c4051145d ("spi: sh-msiof: Avoid writing to registers from spi_master.setup()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Simplify calculation of divisors for transfer rate

The change updates sh_msiof_spi_set_clk_regs() function by iterating
over BRDV power values. Note that the change is a functional one, namely
prescaler output x 1/1 set in BRDV bit field (0b111) for MSO division
rate set to 2 is substituted by BRDV = 0b000 and BRPS = 0b0, in terms
of written values to TSCR setting of 0x0107 is substituted by 0x0000,
and for all input parameter cases this is the only functional change,
which touches the controller.

As a result of the rework the function is supposed to be slightly more
efficient and more readable and maintainable in case of any further
extensions.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fix bit field overflow writes to TSCR/RSCR

The change fixes a bit field overflow which allows to write to higher
bits while calculating SPI transfer clock and setting BRPS and BRDV
bit fields, the problem is reproduced if 'parent_rate' to 'spi_hz'
ratio is greater than 1024, for instance

p->min_div = 2,
MSO rate = 33333333,
SPI device rate = 10000

results in

k = 5, i.e. BRDV = 0b100 or 1/32 prescaler output,
BRPS = 105,
TSCR value = 0x6804, thus MSSEL and MSIMM bit fields are non-zero.

Fixes: 65d5665bb260 ("spi: sh-msiof: Update calculation of frequency dividing")
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use correct enum for DMA transfer direction

Use enum dma_transfer_direction as required by dmaengine_prep_slave_sg()
instead of enum dma_data_direction. This won't change behavior in
practice as the enum values are equivalent.

This fixes two warnings when building with clang:
drivers/spi/spi-sh-msiof.c:755:27: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction' [-Wenum-conversion]
rx->sgl, rx->nents, DMA_FROM_DEVICE,
^~~~~~~~~~~~~~~
drivers/spi/spi-sh-msiof.c:772:27: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction' [-Wenum-conversion]
tx->sgl, tx->nents, DMA_TO_DEVICE,
^~~~~~~~~~~~~

Based on commit 768d59f5d0139a6f ("spi: rspi: use correct enum for DMA
transfer direction").

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fix timeout failures for TX-only DMA transfers

When using RX (with or without TX), the DMA interrupt triggers
completion when the RX FIFO has been emptied, i.e. after the full
transfer has finished.

However, when using TX without RX, the DMA interrupt triggers completion
as soon as the DMA engine has filled the TX FIFO, i.e. before the full
transfer has finished. Then sh_msiof_modify_ctr_wait() will spin until
the transfer has really finished and the TFSE bit is cleared, for at
most 1 ms. For slow speeds and/or large transfers, this may cause
timeouts and transfer failures:

spi_sh_msiof e6e10000.spi: failed to shut down hardware
74x164 spi2.0: SPI transfer failed: -110
spi_master spi2: failed to transfer one message from queue
74x164 spi2.0: Failed writing: -110

Fix this by waiting explicitly until the TX FIFO has been emptied.

Based on a patch in the BSP by Hiromitsu Yamasaki.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Implement cs-gpios configuration

The current support for GPIO chip selects assumes the GPIOs have been
configured by platform code or the boot loader. This includes pinmux
setup and GPIO direction. Hence it does not work as expected when just
described in DT using the "cs-gpios" property.

Fix this by:
1. using devm_gpiod_get_index() to request the GPIO, and thus
configure pinmux, if needed,
2. configuring the GPIO direction is the spi_master.setup() callback.

Use gpio_is_valid() instead of a check on positive numbers.

Note that when using GPIO chip selects, at least one native chip select
must be left unused, as that native chip select will be driven anyway,
and (global) native chip select polarity must be taken into account.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Extend support to 3 native chip selects

Currently only the MSIOF_SYNC signal can be used as a native chip
select. Extend support to up to 3 native chipselects using the
MSIOF_SS1 and MSIOF_SS2 signals.

Inspired by a patch in the BSP by Hiromitsu Yamasaki.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Avoid writing to registers from spi_master.setup()

The spi_master.setup() callback must not change configuration registers,
as that could corrupt I/O that is in progress for other SPI slaves.

The only exception is the configuration of the native chip select
polarity in SPI master mode, as a wrong chip select polarity will cause
havoc during all future transfers to any other SPI slave.

Hence stop writing to registers in sh_msiof_spi_setup(), unless it is
the first call for a controller using a native chip select, or unless
native chip select polarity has changed (note that you'll loose anyway
if I/O is in progress). Even then, only do what is strictly necessary,
instead of calling sh_msiof_spi_set_pin_regs().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use dev_warn_once() instead of open-coding

Use the helper introduced by commit e135303bd5bebcd2 ("device: Add
dev_<level>_once variants") instead of open-coding the same
functionality.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: remove redundant pointer dev

The pointer dev is assigned but never read, hence it is redundant
and can be removed. Cleans up clang warning:

drivers/spi/spi-sh-msiof.c:1198:2: warning: Value stored to 'dev'
is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fix DMA transfer size check

DMA supports 32-bit words only,
even if BITLEN1 of SITMDR2 register is 16bit.

Fixes: b0d0ce8b6b91 ("spi: sh-msiof: Add DMA support")
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use of_device_get_match_data() helper

Use the of_device_get_match_data() helper instead of open coding.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Add compatible strings for r8a774[35]

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Limit minimum divider on R-Car Gen3

On R-Car Gen3 SoCs (excluding R-Car H3 ES1.x, which cannot be used for
SPI due to a hardware erratum), BRPS x BRDV = 1/1 is an invalid divider
setting.
Implement this limitation using an SoC/family-specific minimum divider.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Add slave mode support

Add slave mode support to the MSIOF driver, in both PIO and DMA mode.

For now this only supports the transmission of messages with a size
that is known in advance.

Signed-off-by: Hisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: Timeout handling cleanup, spi core integration, cancellation,
rewording]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Remove useless memory allocation failure message

Printing an error on memory allocation failure is unnecessary.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Do not use C++ style comment

4286db8456f4 ("spi: sh-msiof: Add R-Car Gen 2 and 3 fallback bindings")
added a C++ style comment. This is not in keeping with the style used
for comments elsewhere in this fine. Update it accordingly.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Add R-Car Gen 2 and 3 fallback bindings

In the case of Renesas R-Car hardware we know that there are generations of
SoCs, e.g. Gen 2 and Gen 3. But beyond that it's not clear what the
relationship between IP blocks might be. For example, I believe that
r8a7790 is older than r8a7791 but that doesn't imply that the latter is a
descendant of the former or vice versa.

We can, however, by examining the documentation and behaviour of the
hardware at run-time observe that the current driver implementation appears
to be compatible with the IP blocks on SoCs within a given generation.

For the above reasons and convenience when enabling new SoCs a
per-generation fallback compatibility string scheme is being adopted for
drivers for Renesas SoCs.

Also:
* Deprecate renesas,sh-msiof. It seems poorly named as it is only
compatible with SH-Mobile. It also appears unused in mainline.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Add support for R-Car M3-W

MSIOF in R-Car M3-W (r8a7796) is handled fine by the existing driver.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Avoid invalid clock generator parameters

The conversion from a look-up table to a calculation for clock generator
parameters forgot to take into account that BRDV x 1/1 is valid only if
BRPS is x 1/1 or x 1/2, leading to undefined behavior (e.g. arbitrary
clock rates).

This limitation is documented for the MSIOF module in all supported
SH/R-Mobile and R-Car Gen2/Gen3 ARM SoCs.

Tested on r8a7791/koelsch and r8a7795/salvator-x.

Fixes: 65d5665bb260b034 ("spi: sh-msiof: Update calculation of frequency dividing")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Remove sh_msiof_spi_priv.chipdata

After probe time, the pointer to the sh_msiof_chipdata structure in the
sh_msiof_spi_priv structure is used only for checking the SPI master flags.
As these are also available in the spi_master structure, convert the
users to access those, and remove the pointer.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Fix FIFO size to 64 word from 256 word

The upper limit of Tx/Rx FIFO size is 64 word by the
specification of H/W. This patch corrects to 64 word from 256 word.

Signed-off-by: Koji Matsuoka <koji.matsuoka.xm@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

spi: sh-msiof: Remove obsolete spi_r8a779x_msiof platform_device_id entries

Since commit a483dcbfa21f919c ("ARM: shmobile: lager: Remove legacy
board support"), R-Car Gen2 SoCs are only supported in generic DT-only
ARM multi-platform builds. The driver doesn't need to match platform
devices by name anymore, hence remove the corresponding
platform_device_id entry.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: 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: sh-msiof: remove slave_id settings for DMAEngine

Current sh-msiof sets dma_slave_config :: slave_id field for DMAEngine,
but it is no longer needed. Let's remove it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

spi: sh-msiof: cleanup wait_for_completion return handling

return type of wait_for_completion_timeout is unsigned long not int, this
patch uses the return value of wait_for_completion_timeout in the condition
directly rather than assigning it to an incorrect type variable.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Update calculation of frequency dividing

sh-msiof of frequency dividing does not perform the calculation, driver have
to manage setting value in the table. It is not possible to set frequency
dividing value close to the actual data in this way. This changes from
frequency dividing of table management to setting by calculation.
This driver is able to set a value close to the actual data.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Use async pm_runtime_put() in sh_msiof_spi_setup()

There's no need to use the synchronous version.

Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: fix MDR1_FLD_MASK value

Since the FLD bit field is bit[3:2], the MDR1_FLD_MASK value should
be 0x0000000c.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Configure MSIOF sync signal timing in device tree

The MSIOF controller has DTDL and SYNCDL in SITMDR1 register. So,
this patch adds new properties like the following commit:
d0fb47a5237d8b9576113568bacfd27892308b62
(spi: fsl-espi: Configure FSL eSPI CSBEF and CSAFT)

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: sh-msiof: Add runtime PM lock in initializing

SH-MSIOF driver is enabled autosuspend API of spi framework.
But autosuspend framework doesn't work during initializing.
So runtime PM lock is added in SH-MSIOF driver initializing.

Fixes: e2a0ba547ba31c (spi: sh-msiof: Convert to spi core auto_runtime_pm framework)
Signed-off-by: Hisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.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: sh-msiof: Fix transmit-only DMA transfers

Fix tx/rx mixup, which broke transmit-only transfers.

Introduced by commit 4240305f7cbdc7782aa8bc40cc702775d9ac0839
("spi: sh-msiof: Fix leaking of unused DMA descriptors").

Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Add support for new R-Car Gen2 SoCs

Add support for MSIOF in:
- r8a7792 (R-Car V2H)
- r8a7793 (R-Car M2-N)
- r8a7794 (R-Car E2)

r8a7791 is now called "R-Car M2-W".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Fix transmit-only DMA transfers

Fix tx/rx mixup, which broke transmit-only transfers.

Introduced by commit 4240305f7cbdc7782aa8bc40cc702775d9ac0839
("spi: sh-msiof: Fix leaking of unused DMA descriptors").

Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Return early in sh_msiof_dma_once() where possible

Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Add DT support to DMA setup

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Configure DMA slave bus width

The new Renesas R-Car Gen2 DMA Controller driver (rcar-dmac) requires
explicit configuration of the DMA slave bus width.
Hardcode the DMA transfer size to 4 bytes, as MSIOF DMA is limited to
32-bit words.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Fix leaking of unused DMA descriptors

If dmaengine_prep_slave_sg() or dmaengine_submit() fail, we may leak
unused DMA descriptors.

As per Documentation/dmaengine.txt, once a DMA descriptor has been
obtained, it must be submitted. Hence:
- First prepare and submit all DMA descriptors,
- Prepare the SPI controller for DMA,
- Start DMA by calling dma_async_issue_pending(),
- Make sure to call dmaengine_terminate_all() on all descriptors that
haven't completed.

Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Use correct device for DMA mapping with IOMMU

To function correctly in the presence of an IOMMU, the DMA buffers must be
mapped using the DMA channel's device instead of the MSIOF platform
device's device.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Handle dmaengine_prep_slave_single() failures gracefully

As typically a shmobile SoC has less DMA channels than devices that can use
DMA, we may want to prioritize access to the DMA channels in the future.
This means that dmaengine_prep_slave_single() may start failing
arbitrarily.

Handle dmaengine_prep_slave_single() failures gracefully by falling back to
PIO. This requires moving DMA-specific configuration of the MSIOF device
after the call(s) to dmaengine_prep_slave_single().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Add DMA support

Add DMA support to the MSIOF driver using platform data.

As MSIOF DMA is limited to 32-bit words (requiring byte/wordswapping for
smaller wordsizes), and the group length is limited to 256 words, DMA is
performed on two fixed pages, allocated and mapped at driver initialization
time.

Performance figures (in Mbps) on r8a7791/koelsch at different SPI clock
frequencies for 1024-byte and 4096-byte transfers:

1024 bytes 4096 bytes
- 3.25 MHz: PIO 2.1, DMA 2.6 | PIO 2.8, DMA 3.1
- 6.5 MHz: PIO 3.2, DMA 4.4 | PIO 5.0, DMA 5.9
- 13 MHz: PIO 4.2, DMA 6.6 | PIO 8.2, DMA 10.7
- 26 MHz: PIO 5.9, DMA 10.4 | PIO 12.4, DMA 18.4

Note that DMA is only faster than PIO for transfers that exceed the FIFO
size (typically 64 words / 256 bytes).

Also note that large transfers (larger than the group length for DMA, or
larger than the FIFO size for PIO), should use cs-gpio (with the
appropriate pinmux setup), as the hardware chipselect will be deasserted in
between chunks.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Refactor sh_msiof_transfer_one()

- Move buffer pointer and length setup to the top,
- Make unsigned values unsigned,
- Loop over words and increment pointers instead of recalculating them,
which allows to kill bytes_done.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Improve transfer error handling

- Add a timeout when waiting for the transfer complete interrupt,
- If sh_msiof_spi_stop() fails, there's no need to clear IER, as the
interrupt handler has already done that,
- Propagate transfer failures in sh_msiof_transfer_one().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Extract sh_msiof_spi_{start,stop}() helpers

Based on an old patch by Guennadi Liakhovetski <g.liakhovetski@gmx.de>

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Add more register documentation

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Remove unnecessary platform_set_drvdata()

Drop call to platform_set_drvdata() as driver data is not used
anywhere in the driver.

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

spi: sh-msiof: remove unnecessary OOM messages

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Convert to spi core auto_runtime_pm framework

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Kill sh_msiof_spi_bits and sh_msiof_spi_hz functions

In the implementation of __spi_validate(), spi core will set transfer
bits_per_word and max speed as spi device default if it is not set for
this transfer. So we can remove the same implementation in this driver.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Use core message handling instead of spi-bitbang

The only remaining feature of spi-bitbang used by this driver is the
chipselect() callback, which just does conditional GPIO.
This is handled fine by the SPI core's spi_set_cs(), hence switch the
driver to use the core message handling through our own transfer_one()
method.

As the (optional) GPIO CS is no longer deasserted at spi_master.setup()
time (through spi_bitbang_setup() and the spi_bitbang.chipselect()
callback), we now have to take care of that ourselves.

Remove the call to spi_master_put() in sh_msiof_spi_remove(), as our SPI
master is now registered using devm_spi_register_master()
(spi_bitbang_start() uses the non-managed version).

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Convert to let spi core validate xfer->bits_per_word

Set bits_per_word_mask so the spi core will reject transfers that attempt
to use an unsupported bits_per_word value.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Move clock management to (un)prepare_message()

Move clock management and pin configuration from the bitbang chipselect()
method to the SPI core prepare_message() and unprepare_message() methods.

As spi_master.{,un}prepare_message() is guaranteed to be called in
matching pairs, the clock management synchronization is no longer needed.

As sh_msiof_spi_set_pin_regs() is no longer called at spi_master.setup()
time (through spi_bitbang_setup() and the spi_bitbang.chipselect()
callback), we now have to take care of that ourselves.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Add support for R-Car H2 and M2

Add support for the MSIOF variant in the R-Car H2 (r8a7790) and M2
(r8a7791) SoCs.

Binding documentation:
- Add future-proof "renesas,msiof-<soctype>" compatible values,
- The default for "renesas,rx-fifo-size" is 256 on R-Car H2 and M2,
- "renesas,tx-fifo-size" and "renesas,rx-fifo-size" are deprecated for
soctype-specific bindings,
- Add example bindings.

Implementation:
- MSIOF on R-Car H2 and M2 requires the transmission of dummy data if
data is being received only (cfr. "Set SICTR.TSCKE to 1" and "Write
dummy transmission data to SITFDR" in paragraph "Transmit and Receive
Procedures" of the Hardware User's Manual).
- As RX depends on TX, MSIOF on R-Car H2 and M2 also lacks the RSCR
register (Receive Clock Select Register), and some bits in the RMDR1
(Receive Mode Register 1) and TMDR2 (Transmit Mode Register 2)
registers.
- Use the recently introduced SPI_MASTER_MUST_TX flag to enable support
for dummy transmission in the SPI core, and to differentiate from other
MSIOF implementations in code paths that need this.
- New DT compatible values ("renesas,msiof-r8a7790" and
"renesas,msiof-r8a7791") are added, as well as new platform device
names ("spi_r8a7790_msiof" and "spi_r8a7791_msiof").
- The default RX FIFO size is 256 words on R-Car H2 and M2.

This is loosely based on a set of patches from Takashi Yoshii
<takasi-y@ops.dti.ne.jp>.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Move default FIFO sizes to device ID data

As different variants of MSIOF have different FIFO sizes, move the default
FIFO sizes to a new struct sh_msiof_chipdata, pointed to from the device
ID data.

[Moved ifdef to fix build -- broonie]

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Improve bindings

Documentation:
- Add missing "interrupt-parent", "#address-cells", "#size-cells", and
"clocks" properties,
- Add missing default values for "num-cs", "renesas,tx-fifo-size" and
"renesas,rx-fifo-size",
- Add a reference to the pinctrl documentation.

Implementation:
- As "num-cs" is marked optional, provide a sensible default.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Use the core cs_gpio field, and make it optional

In current implementation, CS is controlled by GPIO, which is passed
through spi->controller_data. However, the MSIOF HW module has a function
to output CS by itself, which is already enabled and actual switch will be
done by pinmux.

Store the GPIO number in the core cs_gpio field, and ignore it if it is
an invalid (negative) GPIO number.

Loosely based on a patch from Takashi Yoshii <takasi-y@ops.dti.ne.jp>.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Add more register documentation

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Change hz from unsigned long to u32

Both spi_transfer.speed_hz and spi_master.max_speed_hz are u32

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Typo in comment s/tx/rx/

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Fix SPI bus population from DT

DT doesn't instantiate SPI children if spi_master.dev.of_node is not set up
properly.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
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-sh-msiof: set hi/low Active for HW CS

Set hardware CS(CS control function on MSIOF <-> GPIO CS) polarity
according to SPI_CS_HIGH flag on spi->mode.

Signed-off-by: Takashi Yoshii <takasi-y@ops.dti.ne.jp>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-sh-msiof: round up div to fix freq calculation

Truncation on integer division in sh_msiof_spi_set_clk_regs()
results in insufficient transfer frequency (> max_speed_freq).

For example, source 52MHz, required max 6MHz
52/6 = 8.6 --> 8, then 1/8 table selected,
and result in 52/8 = 6.5 MHz (>6MHz)

Rounding it up is a simple solution.
52/6 = 8.6 --> 9, then 1/16 table selected,
and result in 52/16 = 3.25 MHz

Signed-off-by: Takashi Yoshii <takasi-y@ops.dti.ne.jp>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Convert to clk_prepare/unprepare

Get the driver ready for the migration to the common clock framework by
calling clk_prepare() and clk_unprepare(). The calls are added in the
probe and remove handlers as the clk_enable() and clk_disable() calls
are located in atomic context and there's no callback function in
non-atomic context that can be used to prepare/unprepare the clock.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Use devm_* managed allocators

This simplifies error and cleanup code paths.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: sh-msiof: Fix warnings due to improper casts

Cast pointers to uintptr_t instead of unsigned int. This fixes warnings
on platforms where pointers have a different size than int.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

tree-wide: use reinit_completion instead of INIT_COMPLETION

Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi/sh-msiof: Remove unneeded empty runtime PM callbacks

Previously the runtime PM API insisted on having callbacks for everything
but this requirement was removed a while ago so the empty callbacks can
also be removed.

Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spi-sh-msiof: Use of_match_ptr() macro

This eliminates having an #ifdef returning NULL for the case
when OF is disabled.

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

spi/sh-msiof: Add device tree parsing to driver

This adds the capability to retrieve setup data from the device tree
node. The usage of platform data is still available.

Signed-off-by: Bastian Hecht <hechtb+renesas@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi/sh-msiof: Remove unneeded clock name

clk_get() no longer needs a character string for associating the right
clock as this is done via the device struct now.

Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: Add module.h to implicit users in drivers/spi

We are clipping down the presence of module.h, since it was
everywhere. If you really need it, you better call it out,
as per this changeset.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

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: irq: Remove IRQF_DISABLED

Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
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>