Commit graph

62 commits

Author SHA1 Message Date
kernel test robot
7a4697b201
spi: stm32: fix excluded_middle.cocci warnings
drivers/spi/spi-stm32.c:915:23-25: WARNING !A || A && B is equivalent to !A || B

 Condition !A || A && B is equivalent to !A || B.

Generated by: scripts/coccinelle/misc/excluded_middle.cocci

Fixes: 7ceb0b8a3c ("spi: stm32: finalize message either on dma callback or EOT")
CC: Alain Volmat <alain.volmat@foss.st.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Reviewed-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/20210713191004.GA14729@5eb5c2cbef84
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-08-20 13:07:27 +01:00
Alain Volmat
7ceb0b8a3c
spi: stm32: finalize message either on dma callback or EOT
Depending on the usage, it is necessary to perform the finalize
message operation either upon receiving the EOT interruption,
eiher upon receiving the DMA callback. Indeed, when relying
on DMA, even if the SPI EOT IT has been received, it is
necessary to wait for the end of the DMA RX transaction before
accessing to the data.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1625646426-5826-8-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-07-11 23:51:43 +01:00
Alain Volmat
dc6620c313
spi: stm32h7: don't wait for EOT and flush fifo on disable
In nominal cases, disable is called as part of the unprepare_message,
after receiving a EOT and after receiving all data so it doesn't
make sense to check for EOT and empty the FIFO.
Moreover, at the end of the disable, the SPI is disable (SPE) leading
to clear of all internal FIFO, leaving the IP in a known status.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1625646426-5826-7-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-07-11 23:51:42 +01:00
Amelie Delaunay
d87a5d64b5
spi: stm32h7: rework rx fifo read function
Remove flush parameter and check RXWNE or RXPLVL when end of transfer
flag is set.

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/1625646426-5826-6-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-07-11 23:51:41 +01:00
Alain Volmat
70526e0b76
spi: stm32: Revert "properly handle 0 byte transfer"
0 byte transfer handling is now done within the core in code added
by commit b306320322 ("spi: Skip zero-length transfers in spi_transfer_one_message()")

This reverts commit 2269f5a8b1 ("spi: stm32: properly handle 0 byte transfer")

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1625646426-5826-5-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-07-11 23:51:40 +01:00
Alain Volmat
9d53541451
spi: stm32: enable pm_runtime autosuspend
This commit enables the pm_runtime autosuspend
and sets a 1ms autosuspend delay.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1625646426-5826-3-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-07-11 23:51:39 +01:00
Alain Volmat
7999d2555c
spi: stm32: fixes pm_runtime calls in probe/remove
Add pm_runtime calls in probe/probe error path and remove
in order to be consistent in all places in ordering and
ensure that pm_runtime is disabled prior to resources used
by the SPI controller.

This patch also fixes the 2 following warnings on driver remove:
WARNING: CPU: 0 PID: 743 at drivers/clk/clk.c:594 clk_core_disable_lock+0x18/0x24
WARNING: CPU: 0 PID: 743 at drivers/clk/clk.c:476 clk_unprepare+0x24/0x2c

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

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/1625646426-5826-2-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-07-07 17:33:52 +01:00
Alain Volmat
e4a5c19888
spi: stm32h7: fix full duplex irq handler handling
In case of Full-Duplex mode, DXP flag is set when RXP and TXP flags are
set. But to avoid 2 different handlings, just add TXP and RXP flag in
the mask instead of DXP, and then keep the initial handling of TXP and
RXP events.
Also rephrase comment about EOTIE which is one of the interrupt enable
bits. It is not triggered by any event.

Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/1625042723-661-3-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-06-30 13:50:32 +01:00
Mark Brown
c7ed5fd5fb
Merge branch 'for-5.12' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.13 2021-04-15 19:29:40 +01:00
Alain Volmat
79c6246ae8
spi: stm32: Fix use-after-free on unbind
stm32_spi_remove() accesses the driver's private data after calling
spi_unregister_master() even though that function releases the last
reference on the spi_master and thereby frees the private data.

Fix by switching over to the new devm_spi_alloc_master() helper which
keeps the private data accessible until the driver has unbound.

Fixes: 8d559a64f0 ("spi: stm32: drop devres version of spi_register_master")

Reported-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1616052290-10887-1-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-03-19 12:24:09 +00:00
Alain Volmat
12ef51b116
spi: stm32: avoid ifdef CONFIG_PM for pm callbacks
Avoid CONFIG_PM preprocessor check for pm suspend/resume
callbacks and identify the functions with __maybe_unused.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1615545329-5496-1-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-03-12 14:30:53 +00:00
Antonio Borneo
8d559a64f0
spi: stm32: drop devres version of spi_register_master
A call to spi_unregister_master() triggers calling remove()
for all the spi devices binded to the spi master.

Some spi device driver requires to "talk" with the spi device
during the remove(), e.g.:
- a LCD panel like drivers/gpu/drm/panel/panel-lg-lg4573.c
  will turn off the backlighting sending a command over spi.
This implies that the spi master must be fully functional when
spi_unregister_master() is called, either if it is called
explicitly in the master's remove() code or implicitly by the
devres framework.

Devres calls devres_release_all() to release all the resources
"after" the remove() of the spi master driver (check code of
__device_release_driver() in drivers/base/dd.c).
If the spi master driver has an empty remove() then there would
be no issue; the devres_release_all() will release everything
in reverse order w.r.t. probe().
But if code in spi master driver remove() disables the spi or
makes it not functional (like in this spi-stm32), then devres
cannot be used safely for unregistering the spi master and the
binded spi devices.

Replace devm_spi_register_master() with spi_register_master()
and add spi_unregister_master() as first action in remove().

Fixes: dcbe0d84df ("spi: add driver for STM32 SPI controller")

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1615545286-5395-1-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-03-12 14:25:33 +00:00
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