spi: spi-geni-qcom: Add SPI Device mode support for GENI based QuPv3

Currently spi geni driver supports only master mode operation.

Add spi device mode support to GENI based QuPv3.

Signed-off-by:

spi: spi-geni-qcom: Add SPI Device mode support for GENI based QuPv3

Currently spi geni driver supports only master mode operation.

Add spi device mode support to GENI based QuPv3.

Signed-off-by: Praveen Talari <quic_ptalari@quicinc.com>
Reviewed-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Link: https://lore.kernel.org/r/20230714042203.14251-3-quic_ptalari@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode

The GPI DMA mode requires for TX DMA to be prepared. Force SPI core to
provide TX buffer even if the caller didn't provide one by s

spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode

The GPI DMA mode requires for TX DMA to be prepared. Force SPI core to
provide TX buffer even if the caller didn't provide one by setting the
SPI_CONTROLLER_MUST_TX flag.

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230629095847.3648597-1-dmitry.baryshkov@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: correctly handle -EPROBE_DEFER from dma_request_chan()

Now spi_geni_grab_gpi_chan() errors are correctly reported, the
-EPROBE_DEFER error should be returned from probe in case t

spi: spi-geni-qcom: correctly handle -EPROBE_DEFER from dma_request_chan()

Now spi_geni_grab_gpi_chan() errors are correctly reported, the
-EPROBE_DEFER error should be returned from probe in case the
GPI dma driver is built as module and/or not probed yet.

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Fixes: 6532582c353f ("spi: spi-geni-qcom: fix error handling in spi_geni_grab_gpi_chan()")
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230615-topic-sm8550-upstream-fix-spi-geni-qcom-probe-v2-1-670c3d9e8c9c@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: correctly handle -EPROBE_DEFER from dma_request_chan()

Now spi_geni_grab_gpi_chan() errors are correctly reported, the
-EPROBE_DEFER error should be returned from probe in case t

spi: spi-geni-qcom: correctly handle -EPROBE_DEFER from dma_request_chan()

Now spi_geni_grab_gpi_chan() errors are correctly reported, the
-EPROBE_DEFER error should be returned from probe in case the
GPI dma driver is built as module and/or not probed yet.

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Fixes: 6532582c353f ("spi: spi-geni-qcom: fix error handling in spi_geni_grab_gpi_chan()")
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230615-topic-sm8550-upstream-fix-spi-geni-qcom-probe-v2-1-670c3d9e8c9c@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Do not do DMA map/unmap inside driver, use framework instead

The spi geni driver in SE DMA mode, unlike GSI DMA, is not making use of
DMA mapping functionality available in the f

spi: spi-geni-qcom: Do not do DMA map/unmap inside driver, use framework instead

The spi geni driver in SE DMA mode, unlike GSI DMA, is not making use of
DMA mapping functionality available in the framework.
The driver does mapping internally which makes dma buffer fields available
in spi_transfer struct superfluous while requiring additional members in
spi_geni_master struct.

Conform to the design by having framework handle map/unmap and do only
DMA transfer in the driver; this also simplifies code a bit.

Fixes: e5f0dfa78ac7 ("spi: spi-geni-qcom: Add support for SE DMA mode")
Suggested-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/1684325894-30252-3-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Select FIFO mode for chip select

Spi geni driver switches between FIFO and DMA modes based on xfer length.
FIFO mode relies on M_CMD_DONE_EN interrupt for completion while DMA mo

spi: spi-geni-qcom: Select FIFO mode for chip select

Spi geni driver switches between FIFO and DMA modes based on xfer length.
FIFO mode relies on M_CMD_DONE_EN interrupt for completion while DMA mode
relies on XX_DMA_DONE.
During dynamic switching, if FIFO mode is chosen, FIFO related interrupts
are enabled and DMA related interrupts are disabled. And viceversa.
Chip select shares M_CMD_DONE_EN interrupt with FIFO to check completion.
Now, if a chip select operation is preceded by a DMA xfer, M_CMD_DONE_EN
interrupt would have been disabled and hence it will never receive one
resulting in timeout.

For chip select, in addition to setting the xfer mode to FIFO,
select_mode() to FIFO so that required interrupts are enabled.

Fixes: e5f0dfa78ac7 ("spi: spi-geni-qcom: Add support for SE DMA mode")
Suggested-by: Praveen Talari <quic_ptalari@quicinc.com
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com
Reviewed-by: Douglas Anderson <dianders@chromium.org
Link: https://lore.kernel.org/r/1683626496-9685-1-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org

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spi: spi-geni-qcom: Correct CS_TOGGLE bit in SPI_TRANS_CFG

The CS_TOGGLE bit when set is supposed to instruct FW to
toggle CS line between words. The driver with intent of
disabling this behaviour h

spi: spi-geni-qcom: Correct CS_TOGGLE bit in SPI_TRANS_CFG

The CS_TOGGLE bit when set is supposed to instruct FW to
toggle CS line between words. The driver with intent of
disabling this behaviour has been unsetting BIT(0). This has
not caused any trouble so far because the original BIT(1)
is untouched and BIT(0) likely wasn't being used.

Correct this to prevent a potential future bug.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org
Fixes: 561de45f72bd ("spi: spi-geni-qcom: Add SPI driver support for GENI based QUP")
Reviewed-by: Douglas Anderson <dianders@chromium.org
Link: https://lore.kernel.org/r/1682412128-1913-1-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org

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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 ar

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>

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spi: geni-qcom: 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 erro

spi: geni-qcom: 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/20230303172041.2103336-30-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

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soc: qcom: geni-se: Move qcom-geni-se.h to linux/soc/qcom/geni-se.h

Move include/linux/qcom-geni-se.h to include/linux/soc/qcom/geni-se.h.
This removes 1 of a few remaining Qualcomm-specific headers

soc: qcom: geni-se: Move qcom-geni-se.h to linux/soc/qcom/geni-se.h

Move include/linux/qcom-geni-se.h to include/linux/soc/qcom/geni-se.h.
This removes 1 of a few remaining Qualcomm-specific headers into a more
approciate subdirectory under include/.

Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Acked-by: Bjorn Andersson <andersson@kernel.org>
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Reviewed-by: Guru Das Srinagesh <quic_gurus@quicinc.com>
Link: https://lore.kernel.org/r/20230203210133.3552796-1-quic_eberman@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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spi: spi-geni-qcom: Add support for SE DMA mode

SE DMA mode can be used for larger transfers and FIFO mode
for smaller transfers.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>

spi: spi-geni-qcom: Add support for SE DMA mode

SE DMA mode can be used for larger transfers and FIFO mode
for smaller transfers.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/1670509544-15977-1-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: qcom: geni: Simplify DMA setting

As stated in [1], dma_set_mask() with a 64-bit mask will never fail if
dev->dma_mask is non-NULL.
So, if it fails, the 32 bits case will also fail for the same

spi: qcom: geni: Simplify DMA setting

As stated in [1], dma_set_mask() with a 64-bit mask will never fail if
dev->dma_mask is non-NULL.
So, if it fails, the 32 bits case will also fail for the same reason.

Simplify code and remove some dead code accordingly.

[1]: https://lkml.org/lkml/2021/6/7/398

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/1b14e4ce91a33c16b2c655389c728071a9c9aa2e.1641643601.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: qcom: geni: handle timeout for gpi mode

We missed adding handle_err for gpi mode, so add a new function
spi_geni_handle_err() which would call handle_fifo_timeout() or newly
added handle_gpi_ti

spi: qcom: geni: handle timeout for gpi mode

We missed adding handle_err for gpi mode, so add a new function
spi_geni_handle_err() which would call handle_fifo_timeout() or newly
added handle_gpi_timeout() based on mode

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Reported-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20220103071118.27220-2-vkoul@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: qcom: geni: set the error code for gpi transfer

Before we invoke spi_finalize_current_transfer() in
spi_gsi_callback_result() we should set the spi->cur_msg->status as
appropriate (0 for succes

spi: qcom: geni: set the error code for gpi transfer

Before we invoke spi_finalize_current_transfer() in
spi_gsi_callback_result() we should set the spi->cur_msg->status as
appropriate (0 for success, error otherwise).

The helps to return error on transfer and not wait till it timesout on
error

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20220103071118.27220-1-vkoul@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: qcom: geni: remove unused defines

Commit b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
added GPI support but also added unused defines, so remove them

Signed-off-by: Vinod Koul

spi: qcom: geni: remove unused defines

Commit b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
added GPI support but also added unused defines, so remove them

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20211117133110.2682631-1-vkoul@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: fix error handling in spi_geni_grab_gpi_chan()

This code has several issues:
1) It passes IS_ERR() to dev_err_probe() instead of PTR_ERR().
2) It always prints an error message,

spi: spi-geni-qcom: fix error handling in spi_geni_grab_gpi_chan()

This code has several issues:
1) It passes IS_ERR() to dev_err_probe() instead of PTR_ERR().
2) It always prints an error message, even when it succeeds.
3) The "if (ret < 0) {" conditions are never true.
4) If requesting "mas->tx" fails then it sets "mas->rx" to NULL but the
intention was to set "mas->tx" to NULL.

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20211110073935.GA5176@kili
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Add support for GPI dma

We can use GPI DMA for devices where it is enabled by firmware. Add
support for this mode

Signed-off-by: Vinod Koul <vkoul@kernel.org>
--
-Changes since

spi: spi-geni-qcom: Add support for GPI dma

We can use GPI DMA for devices where it is enabled by firmware. Add
support for this mode

Signed-off-by: Vinod Koul <vkoul@kernel.org>
--
-Changes since v4:
- Fix the kbuild bot warning

-Changes since v3:
- Drop merged spi core, geni patches
- Remove global structs and use local variables instead
- modularize code more as suggested by Doug
- fix kbuild bot warning

drivers/spi/spi-geni-qcom.c | 254 +++++++++++++++++++++++++++++++++---
1 file changed, 239 insertions(+), 15 deletions(-)
Link: https://lore.kernel.org/r/20211020060954.1531783-1-vkoul@kernel.org

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

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spi: spi-geni-qcom: Remove confusing comment about setting the watermark

The comment in setup_fifo_xfer() about setting the watermark wasn't
quite proper grammar and also stopped making sense around

spi: spi-geni-qcom: Remove confusing comment about setting the watermark

The comment in setup_fifo_xfer() about setting the watermark wasn't
quite proper grammar and also stopped making sense around commit
6d66507d9b55 ("spi: spi-geni-qcom: Don't wait to start 1st transfer if
transmitting"). After that commit we actually start the transfer
_before_ the watermark interrupt comes.

I don't think the comment really has any value anymore. We've already
got a comment when we grab the spinlock saying that our interrupt can
come any time as a result of the things in the locked section. Let's
just remove it.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20210712085010.1.Ie3bb9f9d30d6475bb75251d32635194c1c72b9ee@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: delete repeated words in comments

Drop repeated words in spi-bcm2835aux.c
{are}

Drop repeated words in spi-dw-mmio.c
{the}

Drop repeated words in spi-geni-qcom.c
{our}

Drop repeated words in

spi: delete repeated words in comments

Drop repeated words in spi-bcm2835aux.c
{are}

Drop repeated words in spi-dw-mmio.c
{the}

Drop repeated words in spi-geni-qcom.c
{our}

Drop repeated words in spi-pl022.c
{on}

Drop repeated words in spi-ppc4xx.c
{the}

Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620629903-15493-4-git-send-email-f.fangjian@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Convert to use resource-managed OPP API

Use resource-managed OPP API to simplify code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Mark Brown <broonie@kernel.org

spi: spi-geni-qcom: Convert to use resource-managed OPP API

Use resource-managed OPP API to simplify code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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spi: spi-geni-qcom: Print an error when we timeout setting the CS

If we're using geni to manage the chip select line (don't do it--use a
GPIO!) and we happen to get a timeout waiting for the chip se

spi: spi-geni-qcom: Print an error when we timeout setting the CS

If we're using geni to manage the chip select line (don't do it--use a
GPIO!) and we happen to get a timeout waiting for the chip select
command to be completed, no errors are printed even though things
might not be in the best shape. Let's add a print.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201217142842.v3.4.I666b37646de9652cef438ac7c2c6c2053367fc6b@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Don't try to set CS if an xfer is pending

If we get a timeout sending then this happens:

spi_transfer_one_message()
->transfer_one() AKA spi_geni_transfer_one()
setup_fifo_xf

spi: spi-geni-qcom: Don't try to set CS if an xfer is pending

If we get a timeout sending then this happens:

spi_transfer_one_message()
->transfer_one() AKA spi_geni_transfer_one()
setup_fifo_xfer()
mas->cur_xfer = non-NULL
spi_transfer_wait() => TIMES OUT
if (msg->status != -EINPROGRESS)
goto out
if (ret != 0 ...)
spi_set_cs()
->set_cs AKA spi_geni_set_cs()
# mas->cur_xfer is non-NULL

The above happens _before_ the SPI core calls ->handle_err() AKA
handle_fifo_timeout().

Unfortunately that won't work so well on geni. If we got a timeout
transferring then it's likely that our interrupt handler is blocked,
but we need that same interrupt handler to run and the command channel
to be unblocked in order to adjust the chip select. Trying to set the
chip select doesn't crash us but ends up confusing our state machine
and leads to messages like: Premature done. rx_rem = 32 bpw8

Let's just drop the chip select request in this case. We can detect
the case because cur_xfer is non-NULL--it would have been set to NULL
in the interrupt handler if the previous transfer had finished. Sure,
we might leave the chip select in the wrong state but it's likely it
was going to fail anyway and this avoids getting the driver even more
confused about what it's doing.

The SPI core in general assumes that setting chip select is a simple
operation that doesn't fail. Yet another reason to just reconfigure
the chip select line as GPIOs.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201217142842.v3.3.I07afdedcc49655c5d26880f8df9170aac5792378@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Fail new xfers if xfer/cancel/abort pending

If we got a timeout when trying to send an abort command then it means
that we just got 3 timeouts in a row:

1. The original timeout

spi: spi-geni-qcom: Fail new xfers if xfer/cancel/abort pending

If we got a timeout when trying to send an abort command then it means
that we just got 3 timeouts in a row:

1. The original timeout that caused handle_fifo_timeout() to be
called.
2. A one second timeout waiting for the cancel command to finish.
3. A one second timeout waiting for the abort command to finish.

SPI is clocked by the controller, so nothing (aside from a hardware
fault or a totally broken sequencer) should be causing the actual
commands to fail in hardware. However, even though the hardware
itself is not expected to fail (and it'd be hard to predict how we
should handle things if it did), it's easy to hit the timeout case by
simply blocking our interrupt handler from running for a long period
of time. Obviously the system is in pretty bad shape if a interrupt
handler is blocked for > 2 seconds, but there are certainly bugs (even
bugs in other unrelated drivers) that can make this happen.

Let's make things a bit more robust against this case. If we fail to
abort we'll set a flag and then we'll block all future transfers until
we have no more interrupts pending.

Fixes: 561de45f72bd ("spi: spi-geni-qcom: Add SPI driver support for GENI based QUP")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201217142842.v3.2.Ibade998ed587e070388b4bf58801f1107a40eb53@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Fix geni_spi_isr() NULL dereference in timeout case

In commit 7ba9bdcb91f6 ("spi: spi-geni-qcom: Don't keep a local state
variable") we changed handle_fifo_timeout() so that we s

spi: spi-geni-qcom: Fix geni_spi_isr() NULL dereference in timeout case

In commit 7ba9bdcb91f6 ("spi: spi-geni-qcom: Don't keep a local state
variable") we changed handle_fifo_timeout() so that we set
"mas->cur_xfer" to NULL to make absolutely sure that we don't mess
with the buffers from the previous transfer in the timeout case.

Unfortunately, this caused the IRQ handler to dereference NULL in some
cases. One case:

CPU0 CPU1
---- ----
setup_fifo_xfer()
geni_se_setup_m_cmd()
<hardware starts transfer>
<transfer completes in hardware>
<hardware sets M_RX_FIFO_WATERMARK_EN in m_irq>
...
handle_fifo_timeout()
spin_lock_irq(mas->lock)
mas->cur_xfer = NULL
geni_se_cancel_m_cmd()
spin_unlock_irq(mas->lock)

geni_spi_isr()
spin_lock(mas->lock)
if (m_irq & M_RX_FIFO_WATERMARK_EN)
geni_spi_handle_rx()
mas->cur_xfer NULL dereference!

tl;dr: Seriously delayed interrupts for RX/TX can lead to timeout
handling setting mas->cur_xfer to NULL.

Let's check for the NULL transfer in the TX and RX cases and reset the
watermark or clear out the fifo respectively to put the hardware back
into a sane state.

NOTE: things still could get confused if we get timeouts all the way
through handle_fifo_timeout() and then start a new transfer because
interrupts from the old transfer / cancel / abort could still be
pending. A future patch will help this corner case.

Fixes: 561de45f72bd ("spi: spi-geni-qcom: Add SPI driver support for GENI based QUP")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201217142842.v3.1.I99ee04f0cb823415df59bd4f550d6ff5756e43d6@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>

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spi: spi-geni-qcom: Use the new method of gpio CS control

Let's set the 'use_gpio_descriptors' field so that we use the new way of
requesting the CS GPIOs in the core. This allows us to avoid having

spi: spi-geni-qcom: Use the new method of gpio CS control

Let's set the 'use_gpio_descriptors' field so that we use the new way of
requesting the CS GPIOs in the core. This allows us to avoid having to
configure the CS pins in "output" mode with an 'output-enable' pinctrl
setting.

Cc: Akash Asthana <akashast@codeaurora.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Alexandru M Stan <amstan@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201204193540.3047030-4-swboyd@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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