Commit Graph

50 Commits

Author SHA1 Message Date
Alain Volmat c64e7efe46
spi: stm32: make spurious and overrun interrupts visible
We do not expect to receive spurious interrupts so rise a warning
if it happens.

RX overrun is an error condition that signals a corrupted RX
stream both in dma and in irq modes. Report the error and
abort the transfer in either cases.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-9-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:17:01 +00:00
Amelie Delaunay e1e2093b16
spi: stm32h7: replace private SPI_1HZ_NS with NSEC_PER_SEC
Replace SPI_1HZ_NS private constant with NSEC_PER_SEC, which is easier
to read and understand.

Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-8-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:17:00 +00:00
Alain Volmat c63b95b76e
spi: stm32: defer probe for reset
Defer the probe operation when a reset controller device is expected
but have not yet been probed.

This change replaces use of devm_reset_control_get_exclusive() with
devm_reset_control_get_optional_exclusive() as reset controller is
optional which is now explicitly stated.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-7-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:16:59 +00:00
Etienne Carriere 1c75cfd53e
spi: stm32: driver uses reset controller only at init
Remove reset controller device reference from the device private
structure since it is used only at probe time and can be discarded
once used to reset the SPI device.

Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-6-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:16:59 +00:00
Alain Volmat 084de52328
spi: stm32h7: ensure message are smaller than max size
Ensure that messages given to transfer_one handler can actually be
handled by it. For that purpose rely on the SPI framework
spi_split_transfers_maxsize function to split messages whenever necessary.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-5-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:16:58 +00:00
Amelie Delaunay 5a380b833a
spi: stm32: use bitfield macros
To avoid defining shift and mask separately and hand-coding the bit
manipulation, use the bitfield macros.

Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-4-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:16:57 +00:00
Alain Volmat 8f8d0e3e33
spi: stm32: do not mandate cs_gpio
CS gpios is not mandatory, the driver should allow working
even when CS are not given.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-3-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:16:56 +00:00
Alain Volmat 2269f5a8b1
spi: stm32: properly handle 0 byte transfer
On 0 byte transfer request, return straight from the
xfer function after finalizing the transfer.

Fixes: dcbe0d84df ("spi: add driver for STM32 SPI controller")
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-2-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-02-05 19:16:55 +00:00
Marek Vasut 970e8eaa08
spi: stm32: Simplify stm32h7_spi_prepare_fthlv()
Simplify stm32h7_spi_prepare_fthlv() function implementation,
no functional change intended.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alain Volmat <alain.volmat@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Amelie Delaunay <amelie.delaunay@st.com>
Cc: Antonio Borneo <antonio.borneo@st.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Roman Guskov <rguskov@dh-electronics.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-spi@vger.kernel.org
Link: https://lore.kernel.org/r/20210104123114.261596-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-13 12:19:51 +00:00
Alexandru Ardelean 8b835da617
spi: stm32: update dev_dbg() print format for SPI params
With the introduction of the 'include/uapi/linux/spi/spi.h' header, the
type of the macros are enforced to 'unsigned long int' via the _BITUL()
macro.

This causes some -Wformat warnings in the spi-stm32 driver.
This patch adds a double-negation operator to the bit-masks. Essentially,
the important values for debugging are 0 or 1, while masking them directly
would show 0 or BIT(x) values.
This way, the type of the arguments are automatically re-cast.

Fixes: f7005142da ("spi: uapi: unify SPI modes into a single spi.h header")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210104143103.56510-1-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-05 14:35:28 +00:00
Roman Guskov a590370d91
spi: stm32: FIFO threshold level - fix align packet size
if cur_bpw <= 8 and xfer_len < 4 then the value of fthlv will be 1 and
SPI registers content may have been lost.

* If SPI data register is accessed as a 16-bit register and DSIZE <= 8bit,
  better to select FTHLV = 2, 4, 6 etc

* If SPI data register is accessed as a 32-bit register and DSIZE > 8bit,
  better to select FTHLV = 2, 4, 6 etc, while if DSIZE <= 8bit,
  better to select FTHLV = 4, 8, 12 etc

Signed-off-by: Roman Guskov <rguskov@dh-electronics.com>
Fixes: dcbe0d84df ("spi: add driver for STM32 SPI controller")
Reviewed-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20201221123532.27272-1-rguskov@dh-electronics.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-12-21 17:18:52 +00:00
Zhang Qilong 900ccdcb79
spi: stm32: fix reference leak in stm32_spi_resume
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in stm32_spi_resume, so we should fix it.

Fixes: db96bf976a ("spi: stm32: fixes suspend/resume management")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Reviewed-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/20201106015217.140476-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-06 10:54:49 +00:00
Mark Brown 9887311813
Merge remote-tracking branch 'spi/for-5.10' into spi-next 2020-10-09 16:01:22 +01:00
Barry Song e236893387
spi: spi-stm32: remove redundant irqsave and irqrestore in hardIRQ
Running in hardIRQ, disabling IRQ is redundant.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Link: https://lore.kernel.org/r/20200926001616.21292-2-song.bao.hua@hisilicon.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-10-01 23:45:28 +01:00
Dan Carpenter c170a5a3b6
spi: stm32: fix pm_runtime_get_sync() error checking
The pm_runtime_get_sync() can return either 0 or 1 on success but this
code treats 1 as a failure.

Fixes: db96bf976a ("spi: stm32: fixes suspend/resume management")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/20200909094304.GA420136@mwanda
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-09 15:11:44 +01:00
Krzysztof Kozlowski a05cec2dc2
spi: stm32: Simplify with dev_err_probe()
Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and the error value gets printed.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200901152713.18629-8-krzk@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-08 18:19:29 +01:00
Marek Vasut ea8be08cc9
spi: stm32: Rate-limit the 'Communication suspended' message
The 'spi_stm32 44004000.spi: Communication suspended' message means that
when using PIO, the kernel did not read the FIFO fast enough and so the
SPI controller paused the transfer. Currently, this is printed on every
single such event, so if the kernel is busy and the controller is pausing
the transfers often, the kernel will be all the more busy scrolling this
message into the log buffer every few milliseconds. That is not helpful.

Instead, rate-limit the message and print it every once in a while. It is
not possible to use the default dev_warn_ratelimited(), because that is
still too verbose, as it prints 10 lines (DEFAULT_RATELIMIT_BURST) every
5 seconds (DEFAULT_RATELIMIT_INTERVAL). The policy here is to print 1 line
every 50 seconds (DEFAULT_RATELIMIT_INTERVAL * 10), because 1 line is more
than enough and the cycles saved on printing are better left to the CPU to
handle the SPI. However, dev_warn_once() is also not useful, as the user
should be aware that this condition is possibly recurring or ongoing. Thus
the custom rate-limit policy.

Finally, turn the message from dev_warn() to dev_dbg(), since the system
does not suffer any sort of malfunction if this message appears, it is
just slowing down. This further reduces the printing into the log buffer
and frees the CPU to do useful work.

Fixes: dcbe0d84df ("spi: add driver for STM32 SPI controller")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Amelie Delaunay <amelie.delaunay@st.com>
Cc: Antonio Borneo <borneo.antonio@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200905151913.117775-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-07 12:53:43 +01:00
Alain Volmat 60ccb3515f
spi: stm32: always perform registers configuration prior to transfer
SPI registers content may have been lost upon suspend/resume sequence.
So, always compute and apply the necessary configuration in
stm32_spi_transfer_one_setup routine.

Signed-off-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/1597043558-29668-6-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-10 19:46:45 +01:00
Amelie Delaunay db96bf976a
spi: stm32: fixes suspend/resume management
This patch adds pinctrl power management, and reconfigure spi controller
in case of resume.

Fixes: 038ac869c9 ("spi: stm32: add runtime PM support")

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/1597043558-29668-5-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-10 19:46:44 +01:00
Amelie Delaunay 9cc61973bf
spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
Fix spi->clk_rate when it is odd to the nearest lowest even value because
minimum SPI divider is 2.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/1597043558-29668-4-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-10 19:46:43 +01:00
Amelie Delaunay 3373e9004a
spi: stm32: fix fifo threshold level in case of short transfer
When transfer is shorter than half of the fifo, set the data packet size
up to transfer size instead of up to half of the fifo.
Check also that threshold is set at least to 1 data frame.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/1597043558-29668-3-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-10 19:46:42 +01:00
Antonio Borneo 135dd873d3
spi: stm32h7: fix race condition at end of transfer
The caller of stm32_spi_transfer_one(), spi_transfer_one_message(),
is waiting for us to call spi_finalize_current_transfer() and will
eventually schedule a new transfer, if available.
We should guarantee that the spi controller is really available
before calling spi_finalize_current_transfer().

Move the call to spi_finalize_current_transfer() _after_ the call
to stm32_spi_disable().

Signed-off-by: Antonio Borneo <antonio.borneo@st.com>
Signed-off-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/1597043558-29668-2-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-10 19:46:41 +01:00
Tobias Schramm ae1ba50f1e
spi: stm32: clear only asserted irq flags on interrupt
Previously the stm32h7 interrupt thread cleared all non-masked interrupts.
If an interrupt was to occur during the handling of another interrupt its
flag would be unset, resulting in a lost interrupt.
This patches fixes the issue by clearing only the currently set interrupt
flags.

Signed-off-by: Tobias Schramm <t.schramm@manjaro.org>
Link: https://lore.kernel.org/r/20200804195136.1485392-1-t.schramm@manjaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-05 16:53:48 +01:00
dillon min 61367d0b8f
spi: stm32: Add 'SPI_SIMPLEX_RX', 'SPI_3WIRE_RX' support for stm32f4
in l3gd20 driver startup, there is a setup failed error return from
stm32 spi driver

     "
     [    2.687630] st-gyro-spi spi0.0: supply vdd not found, using dummy
     regulator
     [    2.696869] st-gyro-spi spi0.0: supply vddio not found, using dummy
     regulator
     [    2.706707] spi_stm32 40015000.spi: SPI transfer setup failed
     [    2.713741] st-gyro-spi spi0.0: SPI transfer failed: -22
     [    2.721096] spi_master spi0: failed to transfer one message from queue
     [    2.729268] iio iio:device0: failed to read Who-Am-I register.
     [    2.737504] st-gyro-spi: probe of spi0.0 failed with error -22
     "

after debug into spi-stm32 driver, st-gyro-spi split two steps to read
l3gd20 id

first: send command to l3gd20 with read id command in tx_buf, rx_buf
is null.
second: read id with tx_buf is null, rx_buf not null.

so, for second step, stm32 driver recongise this process as 'SPI_SIMPLE_RX'
from stm32_spi_communication_type(), but there is no related process for this
type in stm32f4_spi_set_mode(), then we get error from
stm32_spi_transfer_one_setup().

we can use two method to fix this bug.
1, use stm32 spi's "In unidirectional receive-only mode (BIDIMODE=0 and
RXONLY=1)". but as our code running in sdram, the read latency is too large
to get so many receive overrun error in interrupts handler.

2, use stm32 spi's "In full-duplex (BIDIMODE=0 and RXONLY=0)", as tx_buf is
null, so add flag 'SPI_MASTER_MUST_TX' to spi master.

Change since V4:
1 remove dummy data sent out by stm32 spi driver
2 add flag 'SPI_MASTER_MUST_TX' to spi master

Signed-off-by: dillon min <dillon.minfei@gmail.com>
Link: https://lore.kernel.org/r/1590378348-8115-8-git-send-email-dillon.minfei@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-05-25 15:56:16 +01:00
Alain Volmat 1c52be8bed
spi: stm32: Fix comments compilation warnings
Fix all functions and structure descriptions to have the driver
warning free when built with W=1.

Signed-off-by: Alain Volmat <alain.volmat@st.com>
Reviewed-by: Amelie Delaunay <amelie.delaunay@st.com>
Link: https://lore.kernel.org/r/1584711857-9162-1-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-03-20 21:01:40 +00:00
Peter Ujfalusi 0a454258fe
spi: stm32: Use dma_request_chan() instead dma_request_slave_channel()
dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191212135550.4634-10-peter.ujfalusi@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-12-16 11:58:28 +00:00
Linus Walleij 8a6553ecdf
spi: stm32: Switch to use GPIO descriptors for CS
This switches the STM32 SPI driver over to using GPIO
descriptors for chip select. Instead of the callbacks for
picking the GPIO lines using the legacy API we just let
the core handle it all using descriptors.

Cc: Fabien Dessenne <fabien.dessenne@st.com>
Cc: Amelie Delaunay <amelie.delaunay@st.com>
Cc: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20191205083401.27077-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-12-09 18:46:13 +00:00
Fabien Dessenne 8d1467a684
spi: stm32: return the get_irq error
During probe, return the "get_irq" error value instead of -ENOENT. This
allows the driver to be defer probed if needed.

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Acked-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02 10:38:41 +09:00
Cezary Gapinski 00505edf95
spi: stm32: add support for STM32F4
Add routines, registers & bitfield definition. Also baud rate divisor
definitions for STM32F4 SPI. This version supports full-duplex,
simplex TX and half-duplex TX communication with 8 or 16-bit per word.
DMA capability is optionally supported for transfer longer than 16 bytes.
For transfer less than 16 bytes frames can be send in discontinuous mode.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:25:48 +00:00
Cezary Gapinski 55166853b2
spi: stm32: introduce compatible data cfg
Prepare support for STM32F4 spi variant by introducing compatible
configuration data.
Move STM32H7 specific stuff to compatible data structure:
 - registers & bit fields
 - routines to control driver
 - baud rate divisor definitions
 - fifo availability
 - split IRQ functions to parts to be called when the IRQ occurs
   and for threaded interrupt what helps to provide less discontinuous
   mode for drivers without FIFO.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:25:35 +00:00
Cezary Gapinski f8bb12f2fa
spi: stm32: add start dma transfer function
Add transfer_one_dma_start function to be more generic for other
stm32 SPI family drivers.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:25:22 +00:00
Cezary Gapinski 9d5fce166c
spi: stm32: split transfer one setup function
Split stm32_spi_transfer_one_setup function into smaller chunks
to be more generic for other stm32 SPI family drivers.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:25:09 +00:00
Cezary Gapinski a9675337ad
spi: stm32: rename interrupt function
Interrupt function is used as a thread so rename it to express
meaning directly by more clear function name.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:24:56 +00:00
Cezary Gapinski 8602663096
spi: stm32: rename STM32 SPI registers to STM32H7
Rename STM32 SPI registers to be related to STM32H7 SPI driver
and not STM32 generally.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:24:43 +00:00
Cezary Gapinski 6962b055a1
spi: stm32: remove SPI LOOP mode
This driver does not support SPI LOOP mode by configuration
in registers.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:24:30 +00:00
Cezary Gapinski d6cea11b09
spi: stm32: use explicit CPOL and CPHA mode bits
Driver supports SPI mode 0 to 3 not only the mode 3.
Use SPI_CPOL and SPI_CPHA indicates that these bits
can be changed to obtain modes 0 - 3.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:24:17 +00:00
Cezary Gapinski 2cbee7f886
spi: stm32: fix DMA configuration with only one channel
When SPI driver is configured to work only with TX or RX DMA channel
then dmaengine functions can dereferene NULL pointer.

Running full-duplex mode when when only RX or TX DMA channel is
available can cause overrun condition or incorrect writing to transmit
buffer so disable this types of DMA configuration and go back to
interrupt mode.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:23:56 +00:00
Cezary Gapinski d4c9134a6c
spi: stm32: use NULL pointer instead of plain integer
Patch fixes sparse warning: Using plain integer as NULL pointer. Replaces
second argument of function devm_clk_get from 0 to NULL.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:23:43 +00:00
Cezary Gapinski d57a984ff7
spi: stm32: switch to SPDX identifier
Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:23:30 +00:00
Alexey Khoroshilov 3dbb3eef91
spi: stm32: Fix error handling in stm32_spi_probe()
clk_get_rate() is below clk_prepare_enable(), so
its error should lead to goto err_clk_disable, not to err_master_put.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-04-17 11:46:23 +01:00
Christos Gkekas 8b5d729a3a spi: stm32: Fix logical error in stm32_spi_prepare_mbr()
stm32_spi_prepare_mbr() is returning an error value when div is less
than SPI_MBR_DIV_MIN *and* greater than SPI_MBR_DIV_MAX, which always
evaluates to false. This should change to use *or*.

Signed-off-by: Christos Gkekas <chris.gekas@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-09-13 09:42:27 -07:00
Philipp Zabel d5e9a4a433 spi: stm32: explicitly request exclusive reset control
Commit a53e35db70 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.

No functional changes.

Cc: Mark Brown <broonie@kernel.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: linux-spi@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-19 17:05:46 +01:00
Amelie Delaunay 7b821a6485 spi: stm32: fix potential dereference null return value
This patch fixes the usage of rx_dma_desc and tx_dma_desc pointers
returned by dmaengine_prep_slave_sg, which can be null.

Detected by CoverityScan, CID#1446587 ("Dereference null return value")

Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:00:55 +01:00
Amelie Delaunay c67ad368cf spi: stm32: enhance DMA error management
This patch reworks DMA error management. In case the DMA callback is
called while EOT (End Of Transfer) flag is not set, that means that DMA
encountered an error. This error will result in an auto-suspend of SPI
flow, which could also result in an overrun. So, in DMA mode, SUSP and
OVR flags are a condition to stop the current transfer.

Moreover, stm32_spi_can_dma doesn't care about the state of dma channels.
During driver probe, master->can_dma is initialised if dma channel request
is successful. That's why we must use master->can_dma to know if dma
use is possible (dma channel are successfully requested and the transfer
size is greater than fifo size).

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:00:54 +01:00
Amelie Delaunay 038ac869c9 spi: stm32: add runtime PM support
This patch reworks suspend and resume callbacks and add runtime_suspend
and runtime_resume callbacks.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:00:54 +01:00
Amelie Delaunay 128ebb89c5 spi: stm32: use normal conditional statements instead of ternary operator
This patch replace ternary operator use by normal condition statements
to ease code reading.
It also removes redundant !!.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:00:53 +01:00
Amelie Delaunay 042c1c60df spi: stm32: replace st, spi-midi with st, spi-midi-ns to fit bindings
This patch fixes the optional dt property used to set master inter-data
idleness.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:00:53 +01:00
Amelie Delaunay c5fe2faaba spi: stm32: fix compatible to fit with new bindings
This patch updates of_device_id compatible string to fit with new
bindings.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-28 20:00:48 +01:00
Colin Ian King a2f07d38d6 spi: stm32: fix error check on mbr being -ve
The error check of mbr < 0 is always false because mbr is a u32. Make
mbt an int so that a -ve error return from stm32_spi_prepare_mbr can be
detected.

Detected by CoverityScan, CID#1446586 ("Unsigned compared against 0")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-23 12:26:38 +01:00
Amelie Delaunay dcbe0d84df spi: add driver for STM32 SPI controller
The STM32 Serial Peripheral Interface (SPI) can be used to communicate
with external devices while using the specific synchronous protocol. It
supports a half-duplex, full-duplex and simplex synchronous, serial
communication with external devices with 4-bit to 16/32-bit per word. It
has two 8x/16x 8-bit embedded Rx and TxFIFOs with DMA capability. It can
operate in master or slave mode.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-21 16:15:54 +01:00