Extract the common parts of rspi_transfer_one(), rspi_rz_transfer_one(),
and qspi_transfer_out_in() into the new function rspi_common_transfer().
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Enable DMA support for RSPI on r7s72100 (RZ/A1H).
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Enable DMA support for QSPI on R-Car Gen2, for Single, Dual, and Quad SPI
Transfers.

Performance figures for reading from a QSPI FLASH driven at 24.375 MHz
on r8a7791/koelsch:
  - Single:  1.1 Mbps PIO, 23 Mbps DMA
  - Dual  : 12.7 Mbps PIO, 48 Mbps DMA
  - Quad  : 13   Mbps PIO, 70 Mbps DMA
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>

rspi_send_dma() and rspi_send_receive_dma() are very similar. Consolidate
into a single function rspi_dma_transfer(), and add missing checks for
dmaengine_submit() failures.

Both sg_table pointer parameters can be NULL, as RSPI supports TX-only
mode, and unidirectional DMA transfers will also be needed later for
Dual/Quad DMA support.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

The DMA routines only need access to the scatter-gather tables inside the
spi_transfer structures, hence just pass those.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Refactor RSPI (on SH) DMA handling to make it reusable for other RSPI
implementations:
  - Call the DMA routines after configuring the TX Mode bit and after
    calling rspi_receive_init(), so these RSPI-specific operations can be
    removed from the DMA routines,
  - Absorb rspi_transfer_out_in() into rspi_transfer_one().
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Use the SPI core DMA mapping framework instead of our own.
If available, DMA is used for transfers larger than the FIFO size
(8 or 32 bytes).
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

The SPI DMA core framework needs both RX and TX DMA to function.  As a
preparation for converting the driver to use this framework, fall back to
PIO if no DMA channel or only one DMA channel is available.

This affects only RSPI, which could do DMA transfers for TX-only before.
RSPI-RZ and QSPI (at least for Single SPI Transfers) will need both RX and
TX DMA anyway.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

The resource is know to exist, as rspi_probe() already mapped it.
Remove the test, and just pass the resource.
Pass the device pointer instead of the platform device pointer, as the
latter is no longer needed.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Setup of the receive and transmit DMA channels is very similar, so let's
consolidate.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Fall back to PIO if DMA configuration failed.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

The various PIO loops are very similar. Consolidate into a single
function rspi_pio_transfer().

Both buffer pointers can be NULL, as RSPI supports TX-only mode, and
Dual/Quad SPI Transfers are unidirectional.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

RSPI needs dummy transfers to generate the SPI clock on receive.
RSPI-RZ and QSPI always do both transmit and receive.

Use the SPI core SPI_MASTER_MUST_RX/SPI_MASTER_MUST_TX infrastructure
instead of checking for the presence of buffers and providing dummy data
ourselves (for PIO), or providing a dummy buffer (for DMA).

rspi_receive_dma() now provides full duplex DMA transfers on RSPI, and is
renamed to rspi_send_receive_dma().

As the SPI core will always provide a TX buffer, the logic to choose
between DMA send and DMA send/receive in rspi_transfer_one() now has to
check for the presence of an RX buffer. Likewise for the DMA availability
tests in rspi_is_dma().

The buffer tests in qspi_transfer_one() are now always true, so they're
removed.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

The 16-bit DMA support doesn't fit well within the SPI core DMA framework,
as it needs to manage its own double-sized temporary buffers, for handling
the interleaved data.
Remove it, as there is no in-tree board code that sets
rspi_plat_data.dma_width_16bit.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

Since commit 8449fd76 ("spi: rspi: Merge
rspi_send_pio() and rspi_receive_pio()"), rspi_receive_init() is called
for transmit-only transfers too, while this is not needed.
Only call rspi_receive_init() when receiving, to preserve behavior on
RSPI on SH.
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>

In commit 7dd62787 (spi/pxa2xx: Convert
to core runtime PM) master->auto_runtime_pm was set to true.

In this case pm_runtime_enable() must be called *before*
spi_register_master(), otherwise the kernel hangs with this error
message:

  spi_master spi0: Failed to power device: -13

A similar fix, but for spi/hspi, was applied in
268d7643.
Signed-off-by: NAntonio Ospite <ao2@ao2.it>
Signed-off-by: NMark Brown <broonie@linaro.org>

By default for every espi transfer, the rx_buf is placed right after the
tx_buf. This can lead to a buffer overflow when the size of both the TX
and RX data cumulated is higher than the allocated 64K buffer for the
transfer (this is the case when sending for instance a read command and
reading 64K back, please see:
http://article.gmane.org/gmane.linux.drivers.mtd/53411 )

This gets fixed by always setting the RX buffer pointer at the begining
of the transfer buffer.

[The driver shouldn't be doing the copy in the first place and instead
sending directly from the supplied buffer but this is at least not worse
than what's there -- broonie]
Signed-off-by: NValentin Longchamp <valentin.longchamp@keymile.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Rejecting unsupported values of spi-tx-bus-width and spi-rx-bus-width
may break compatibility with future DTs. Just ignore them, falling back
to Single SPI Transfers.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

The calculation of the bit rate divider used a standard C division, which
rounds down the quotient. This may lead to a higher bitrate than requested.
Round up to avoid this.

E.g. on Koelsch, the SPI flash (configured for 30 MHz) was driven at 48.75
MHz. After this patch it's driven at a safe 24.375 MHz.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

current PIO tranfer method be described as follows:
1. fill as much as bytes but no more than 256 bytes(fifo size)
2. enable oflow/uflow/txfifo_empty interrupt
3. isr process 3 interrupt signal, do complete works.
4. after isr done, if there are left bytes go into 1 else go into 5
5. transfer end

by current PIO transfer method:
1. reduce interrupt counts in spi interrupt line.
2. reduce interrupt latency because no do data fill/fetch in isr.
Signed-off-by: NQipan Li <Qipan.Li@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

The spi-topcliff-pch driver is for a companion chip to the Intel Atom
E600 series processors. These are 32-bit x86 processors so the driver
is only needed on X86_32. Add COMPILE_TEST as an alternative, so that
the driver can still be build-tested elsewhere.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

This patch fixes the calculation for determining whether to use FIFO or BLOCK
mode.
Signed-off-by: NAndy Gross <agross@codeaurora.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

In case we are doing DMA transfer and the size of the buffer is not multiple
of 4 bytes the driver truncates that to 4-byte boundary and tries to handle
remaining bytes using PIO.

Or that is what it tried to do. What actually happens is that it calls
ALIGN() to the buffer size which aligns it to the next 4-byte boundary
(doesn't truncate). Doing this results 1-3 bytes extra to be transferred.
Furthermore we handle remaining bytes using PIO which results one extra
byte to be transferred. In worst case the driver transfers 4 extra bytes.

While investigating this it turned out that the DMA hardware doesn't even
have such limitation so we can solve this by dropping the code that tries
to handle unaligned bytes.
Reported-by: NChiau Ee Chew <chiau.ee.chew@intel.com>
Reported-by: NHock Leong Kweh <hock.leong.kweh@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

The dw_spi_cleanup() function was removed by commit c63f5da0
"spi: dw: Don't call kfree for memory allocated by devm_kzalloc".

commit ec37e8e1 "spi: dw: migrate to generic queue infrastructure" added
dw_spi_cleanup() but never use it. So now I got below build warning:

  CC [M]  drivers/spi/spi-dw.o
drivers/spi/spi-dw.c:609:13: warning: 'dw_spi_cleanup' defined but not used [-Wunused-function]
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NBaruch Siach <baruch@tkos.co.il>
Signed-off-by: NMark Brown <broonie@linaro.org>

Make of_device_id array const, because all OF functions
handle it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Make of_device_id array const, because all OF functions
handle it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Make of_device_id array const, because all OF functions
handle it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Make of_device_id array const, because all OF functions
handle it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Reviewed-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Make of_device_id array const, because all OF functions
handle it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Make of_device_id array const, because all OF functions
handle it as const.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Found using smatch:
drivers/spi/spi-atmel.c:878 atmel_spi_pump_pio_data() warn: unsigned
'as->current_remaining_bytes' is never less than zero.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

If we fail to create the master queue for some reason we should not attempt
to clean it up since attempting to stop a kthread that was not created will
hang and it's just generally bad practice. Unfortunately at present we call
spi_destroy_queue() even in cases where the creation fails.

Fix this by fixing the error handling in spi_master_initialize_queue() so
that we only flag the master as queued or destroy the queue if creation
succeeded. The change to the flag is done since the general master
cleanup uses this to destroy the queue.
Reported-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>

pm_runtime_get_sync() returns 1 if !CONFIG_PM_RUNTIME.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

If NO_DMA=y:

drivers/built-in.o: In function `spi_map_buf':
spi.c:(.text+0x21bc60): undefined reference to `dma_map_sg'
drivers/built-in.o: In function `spi_unmap_buf.isra.33':
spi.c:(.text+0x21c32e): undefined reference to `dma_unmap_sg'
make[3]: *** [vmlinux] Error 1

Protect the DMA code by #ifdef CONFIG_HAS_DMA to fix this:
  - Extract __spi_map_msg() from spi_map_msg(),
  - Provide dummy definitions of __spi_map_msg() and spi_unmap_msg() if
    !CONFIG_HAS_DMA.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
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>
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>
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>

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