Commit Graph

111 Commits

Author SHA1 Message Date
Wolfram Sang ea9d001550
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>
2022-08-29 12:41:36 +01:00
Krzysztof Kozlowski 3323129a6d
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>
2021-09-17 13:17:50 +01:00
Wolfram Sang a26dee29ec
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>
2021-06-23 16:33:53 +01:00
Geert Uytterhoeven 81f68479ec
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>
2021-01-13 12:19:09 +00:00
Geert Uytterhoeven 9a133f7b72
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>
2021-01-13 12:19:08 +00:00
Aishwarya R 21fb1f41bc
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>
2020-04-14 18:36:34 +01:00
Krzysztof Kozlowski 8ae7d44239
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>
2020-01-09 13:27:05 +00:00
Geert Uytterhoeven aa32f76e0a
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>
2020-01-07 22:32:48 +00:00
Geert Uytterhoeven 920d947af9
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>
2019-08-07 14:24:47 +01:00
Stephen Boyd 6b8ac10e0d
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>
2019-08-02 12:15:43 +01:00
Geert Uytterhoeven 635bdb7a3e
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>
2019-05-28 15:57:03 +01:00
Geert Uytterhoeven 9fda669333
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>
2019-04-04 13:00:47 +07:00
Geert Uytterhoeven fedd694068
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>
2019-04-03 11:32:27 +07:00
Geert Uytterhoeven 9115b4d89b
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>
2019-04-03 11:32:26 +07:00
Geert Uytterhoeven 5a4df21e83
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>
2019-04-03 11:23:33 +07:00
Geert Uytterhoeven 0e836c3bea
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>
2019-03-04 00:02:28 +00:00
Geert Uytterhoeven 35c35fd925
spi: sh-msiof: Replace spi_master by spi_controller
As of commit 8caab75fd2 ('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>
2019-02-08 13:04:32 +00:00
Hoan Nguyen An d05e3eadb1
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>
2019-01-18 18:20:52 +00:00
Hoan Nguyen An f70351ae06
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>
2019-01-18 18:20:39 +00:00
Hoan Nguyen An 916d9802e4
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>
2018-12-20 14:56:11 +00:00
Wolfram Sang 07c7df3ecd
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>
2018-11-05 11:54:20 +00:00
Mark Brown 4b51c747e4
Merge branch 'spi-4.20' into spi-next 2018-10-21 17:00:14 +01:00
Sergei Shtylyov f34c6e6257
spi: sh-msiof: fix deferred probing
Since commit 9ec36cafe4 ("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: 9ec36cafe4 ("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>
2018-10-15 12:15:44 +01:00
Hiromitsu Yamasaki 31a5fae4c5
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
2018-09-05 12:39:57 +01:00
Gaku Inami ffa69d6a16
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
2018-09-05 12:39:46 +01:00
Wolfram Sang 9135bac325
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>
2018-08-28 20:32:00 +01:00
Geert Uytterhoeven 08ba7ae35b
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>
2018-06-18 12:47:09 +01:00
Mark Brown 16c10b3bf8
Merge branch 'spi-4.17' into spi-4.18 for the merge window 2018-06-04 11:51:12 +01:00
Geert Uytterhoeven 0921e11e1e
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: 7ff0b53c40 ("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>
2018-05-24 15:15:39 +01:00
Vladimir Zapolskiy 51093cba29
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>
2018-04-17 11:46:52 +01:00
Vladimir Zapolskiy 10b4640833
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: 65d5665bb2 ("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>
2018-04-16 15:52:44 +01:00
Geert Uytterhoeven da779513d3
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 768d59f5d0 ("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>
2018-03-22 09:38:53 +08:00
Mark Brown 977b06d0a4
Merge remote-tracking branches 'spi/topic/pxa2xx', 'spi/topic/s3c64xx', 'spi/topic/sh-msiof', 'spi/topic/sirf' and 'spi/topic/sun6i' into spi-next 2018-01-26 17:57:31 +00:00
Geert Uytterhoeven 89434c3c35
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>
2018-01-03 17:42:42 +00:00
Geert Uytterhoeven b8761434bd
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>
2017-12-14 11:46:14 +00:00
Geert Uytterhoeven 9cce882bed
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>
2017-12-14 11:46:07 +00:00
Geert Uytterhoeven 7ff0b53c40
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>
2017-12-14 11:46:02 +00:00
Geert Uytterhoeven 5d8e614f6c
spi: sh-msiof: Use dev_warn_once() instead of open-coding
Use the helper introduced by commit e135303bd5 ("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>
2017-11-30 16:57:06 +00:00
Mark Brown abbdb5ce31
Merge remote-tracking branches 'spi/topic/sh-msiof', 'spi/topic/slave', 'spi/topic/spreadtrum' and 'spi/topic/tegra114' into spi-next 2017-11-10 21:33:51 +00:00
Colin Ian King 6ae6678344
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>
2017-11-03 17:21:34 +00:00
Hiromitsu Yamasaki 36735783fd
spi: sh-msiof: Fix DMA transfer size check
DMA supports 32-bit words only,
even if BITLEN1 of SITMDR2 register is 16bit.

Fixes: b0d0ce8b6b ("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>
2017-11-02 11:25:44 +00:00
Geert Uytterhoeven ecb1596aa2 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>
2017-10-04 15:48:20 +01:00
Fabrizio Castro bdacfc7b62 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>
2017-09-25 17:13:34 +01:00
Geert Uytterhoeven 61a8dec502 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>
2017-07-17 12:09:59 +01:00
Hisashi Nakamura cf9e4784f3 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>
2017-05-26 13:11:54 +01:00
Geert Uytterhoeven e7ad4a7336 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>
2017-01-04 17:39:37 +00:00
Simon Horman 264c3e8de4 spi: sh-msiof: Do not use C++ style comment
4286db8456 ("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>
2016-12-20 11:40:57 +00:00
Simon Horman 4286db8456 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>
2016-12-14 17:38:18 +00:00
Geert Uytterhoeven eb51cffa74 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>
2016-11-21 18:30:36 +00:00
Geert Uytterhoeven c3ccf357c3 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: 65d5665bb2 ("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>
2016-08-05 11:46:07 +01:00