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

Since commit a483dcbf ("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: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NMark Brown <broonie@kernel.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

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: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NMark Brown <broonie@kernel.org>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

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

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

There's no need to use the synchronous version.
Reported-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@kernel.org>

Since the FLD bit field is bit[3:2], the MDR1_FLD_MASK value should
be 0x0000000c.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@kernel.org>

The MSIOF controller has DTDL and SYNCDL in SITMDR1 register. So,
this patch adds new properties like the following commit:
  d0fb47a5
  (spi: fsl-espi: Configure FSL eSPI CSBEF and CSAFT)
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

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: e2a0ba54 (spi: sh-msiof: Convert to spi core auto_runtime_pm framework)
Signed-off-by: NHisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

A platform_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

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

Introduced by commit 4240305f7cbdc7782aa8bc40cc702775d9ac0839
("spi: sh-msiof: Fix leaking of unused DMA descriptors").
Reported-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

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

Introduced by commit 4240305f7cbdc7782aa8bc40cc702775d9ac0839
("spi: sh-msiof: Fix leaking of unused DMA descriptors").
Reported-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

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

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

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: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

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

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

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

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

Based on an old patch by Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

Drop call to platform_set_drvdata() as driver data is not used
anywhere in the driver.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NMark Brown <broonie@linaro.org>

The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

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: NAxel Lin <axel.lin@ingics.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

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

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

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

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

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

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

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

Both spi_transfer.speed_hz and spi_master.max_speed_hz are u32
Signed-off-by: NGeert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

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

DT doesn't instantiate SPI children if spi_master.dev.of_node is not set up
properly.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: NMark Brown <broonie@linaro.org>