Change snprintf to scnprintf. There are generally two cases where using
snprintf causes problems.
1) Uses of size += snprintf(buf, SIZE - size, fmt, ...)
In this case, if snprintf would have written more characters than what the
buffer size (SIZE) is, then size will end up larger than SIZE. In later
uses of snprintf, SIZE - size will result in a negative number, leading
to problems. Note that size might already be too large by using
size = snprintf before the code reaches a case of size += snprintf.
2) If size is ultimately used as a length parameter for a copy back to user
space, then it will potentially allow for a buffer overflow and information
disclosure when size is greater than SIZE. When the size is used to index
the buffer directly, we can have memory corruption. This also means when
size = snprintf... is used, it may also cause problems since size may become
large. Copying to userspace is mitigated by the HARDENED_USERCOPY kernel
configuration.
The solution to these issues is to use scnprintf which returns the number of
characters actually written to the buffer, so the size variable will never
exceed SIZE.
Signed-off-by: Silvio Cesare <silvio.cesare@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In SPI read-only mode, we will always return the writing length,
which is always the power of "bits_per_word", but the length unit
using by users is byte.
Thus this patch fixes the returning length by getting from
read_bufs() function to get the correct length.
Signed-off-by: Lanqing Liu <lanqing.liu@spreadtrum.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit b682cffa3a ("spi: omap2-mcspi: Set FIFO DMA trigger level to word length")
broke SPI transfers where bits_per_word != 8. This is because of
mimsatch between McSPI FIFO level event trigger size (SPI word length) and
DMA request size(word length * maxburst). This leads to data
corruption, lockup and errors like:
spi1.0: EOW timed out
Fix this by setting DMA maxburst size to 1 so that
McSPI FIFO level event trigger size matches DMA request size.
Fixes: b682cffa3a ("spi: omap2-mcspi: Set FIFO DMA trigger level to word length")
Cc: stable@vger.kernel.org
Reported-by: David Lechner <david@lechnology.com>
Tested-by: David Lechner <david@lechnology.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently the driver calls pm_runtime_put_autosuspend but without ever
having done a pm_runtime_get, this causes the reference count in the pm
runtime core to become -1. The bad reference count causes the core to
sometimes suspend whilst an active SPI transfer is in progress.
arizona spi0.1: SPI transfer timed out
spi_master spi0: failed to transfer one message from queue
The correct proceedure is to do all the initialisation that requires the
hardware to be powered up before enabling the PM runtime, then enable
the PM runtime having called pm_runtime_set_active to inform it that the
hardware is currently powered up. The core will then power it down at
it's leisure and no explicit pm_runtime_put is required.
Fixes: d36ccd9f7e ("spi: cadence: Runtime pm adaptation")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We don't need this forward declaration. Move the function to where it
needed so we can drop it and shave some lines of code.
CC: Girish Mahadevan <girishm@codeaurora.org>
CC: Dilip Kota <dkota@codeaurora.org>
CC: Alok Chauhan <alokc@codeaurora.org>
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
We only use this completion when we're doing something that isn't a
message transfer. For example, changing CS or aborting/canceling a
command. All of those situations properly reinitialize the completion
before sending the GENI the special command to change CS or cancel, etc.
Given that, let's remove the initialization here.
Cc: Girish Mahadevan <girishm@codeaurora.org>
Cc: Dilip Kota <dkota@codeaurora.org>
Cc: Alok Chauhan <alokc@codeaurora.org>
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The previous commit left a variable unused, my bad.
Clean it up.
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: David Lechner <david@lechnology.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 101a68e74f ("spi: davinci: Convert to use CS GPIO descriptors")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
When CONFIG_SPI_DESIGNWARE are enabled we see the unused variable
warning in dw_spi_setup.
../drivers/spi/spi-dw.c: In function ‘dw_spi_setup’:
../drivers/spi/spi-dw.c:400:6: warning: unused variable ‘ret’ [-Wunused-variable]
int ret;
^~~
Remove the unused varable.
Fixes: 9400c41e77 ("spi: dw: Convert to use CS GPIO descriptors")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the DesignWare (dw) SPI master driver to
use GPIO descriptors for chip select handling.
This driver has a duplicate DT parser in addition to the
one in the core, sets up the line as non-asserted and
relies on the core to drive the GPIOs.
It is a pretty straight-forward conversion.
Cc: Talel Shenhar <talel@amazon.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Linuxarm <linuxarm@huawei.com>
Tested-by: Jay Fang <f.fangjian@huawei.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the DaVinci SPI master driver to use GPIO
descriptors for chip select handling.
DaVinci parses the device tree a second time for the chip
select GPIOs (no relying on the parsing already happening
in the SPI core) and handles inversion semantics locally.
We simply drop the extra parsing and set up and move the
CS handling to the core and gpiolib. The fact that the
driver is actively driving the GPIO in the
davinci_spi_chipselect() callback is confusing since the
host does not set SPI_MASTER_GPIO_SS so this should not
ever get called when using GPIO CS. I put in a comment
about this.
This driver also supports instantiation from board files,
but these are all using native chip selects so no problem
with GPIO lines here.
Cc: David Lechner <david@lechnology.com>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Linuxarm <linuxarm@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the CLPS711x SPI master driver to use GPIO
descriptors for chip select handling.
The CLPS711x driver was merely requesting the GPIO and
setting the CS line non-asserted so this was a pretty
straight-forward conversion. The setup callback goes away.
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Linuxarm <linuxarm@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the Cadence SPI master driver to use GPIO
descriptors for chip select handling.
The Cadence driver was allocating a state container just
to hold the requested GPIO line and contained lots of
polarity inversion code. As this is all handled by gpiolib
and a simple devm_* request in the core, and as the driver
is fully device tree only, most of this code chunk goes
away in favour of central handling. The setup/cleanup
callbacks goes away.
This driver does NOT drive the CS line by setting the
value of the GPIO so it relies on the SPI core to do
this, which should work just fine with the descriptors.
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Janek Kotas <jank@cadence.com>
Cc: Linuxarm <linuxarm@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the Atmel SPI master driver to use GPIO descriptors
for chip select handling.
The Atmel driver has duplicate code to look up and initialize CS
GPIOs from the device tree, so this is removed. It further has code
to retrieve a CS GPIO from .controller_data but this seems to be
completely unused in the kernel (legacy codepath?) so I deleted
this support. It keeps track of polarity when switching the CS, but
this is not needed anymore since we moved this over to the gpiolib.
The local handling of the "npcs_pin" (I guess this might mean
"negative polarity chip select pin") is preserved, but I strongly
suspect this can be switched over to handling by the core and
using the SPI_MASTER_GPIO_SS flag on the master to assure that
the additional CS handling in the driver is also done.
Cc: Eugen Hristev <eugen.hristev@microchip.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Radu Pirea <radu.pirea@microchip.com>
Cc: Linuxarm <linuxarm@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the ATH79 SPI master driver to use GPIO descriptors
for chip select handling.
The ATH79 driver was requesting the GPIO and driving it from the
bitbang .chipselect callback. Do not request it anymore as the SPI
core will request it, remove the line inversion semantics for the
GPIO case (handled by gpiolib) and let the SPI core deal with
requesting the GPIO line from the device tree node of the controller.
This driver can be instantiated from a board file (no device tree)
but the board files only use native CS (no GPIO lines) so we should
be fine just letting the SPI core grab the GPIO from the device.
The fact that the driver is actively driving the GPIO in the
ath79_spi_chipselect() callback is confusing since the host does
not set SPI_MASTER_GPIO_SS so this should not ever get called when
using GPIO CS. I put in a comment about this.
Cc: Felix Fietkau <nbd@nbd.name>
Cc: Alban Bedel <albeu@free.fr>
Cc: Linuxarm <linuxarm@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This augments the SPI core to optionally use GPIO descriptors
for chip select on a per-master-driver opt-in basis.
Drivers using this will rely on the SPI core to look up
GPIO descriptors associated with the device, such as
when using device tree or board files with GPIO descriptor
tables.
When getting descriptors from the device tree, this will in
turn activate the code in gpiolib that was
added in commit 6953c57ab1
("gpio: of: Handle SPI chipselect legacy bindings")
which means that these descriptors are aware of the active
low semantics that is the default for SPI CS GPIO lines
and we can assume that all of these are "active high" and
thus assign SPI_CS_HIGH to all CS lines on the DT path.
The previously used gpio_set_value() would call down into
gpiod_set_raw_value() and ignore the polarity inversion
semantics.
It seems like many drivers go to great lengths to set up the
CS GPIO line as non-asserted, respecting SPI_CS_HIGH. We pull
this out of the SPI drivers and into the core, and by simply
requesting the line as GPIOD_OUT_LOW when retrieveing it from
the device and relying on the gpiolib to handle any inversion
semantics. This way a lot of code can be simplified and
removed in each converted driver.
The end goal after dealing with each driver in turn, is to
delete the non-descriptor path (of_spi_register_master() for
example) and let the core deal with only descriptors.
The different SPI drivers have complex interactions with the
core so we cannot simply change them all over, we need to use
a stepwise, bisectable approach so that each driver can be
converted and fixed in isolation.
This patch has the intended side effect of adding support for
ACPI GPIOs as it starts relying on gpiod_get_*() to get
the GPIO handle associated with the device.
Cc: Linuxarm <linuxarm@huawei.com>
Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Fangjian (Turing) <f.fangjian@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
We already need to zero out memory for dma_alloc_coherent(), as such
using dma_zalloc_coherent() is superflous. Phase it out.
This change was generated with the following Coccinelle SmPL patch:
@ replace_dma_zalloc_coherent @
expression dev, size, data, handle, flags;
@@
-dma_zalloc_coherent(dev, size, handle, flags)
+dma_alloc_coherent(dev, size, handle, flags)
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
[hch: re-ran the script on the latest tree]
Signed-off-by: Christoph Hellwig <hch@lst.de>
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>
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>
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>
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>
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>
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>
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>
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>
Fix typo from STMicroelectonics to STMicroelectronics.
Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
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>
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>
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>
spi::mode is defined by framework for several SPI capabilities,
such as polarity, phase, bit-endian, wire number. Directly use this
variable for setting controller's polarity and phase causes other
bit in register being set. Since SPI framework has its definition,
SPI_CPOL and SPI_CPHA offset may be changed by framwork change.
Instead of just mask off the relevant bits,
fetch required bit in spi::mode and set to register.
Signed-off-by: shaftarger <shol@livemail.tw>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add some cpu families that are actually using the fsl-dspi module
in the related Kconfig description.
Signed-off-by: Angelo Dureghello <angelo@sysam.it>
Signed-off-by: Mark Brown <broonie@kernel.org>
On ColdFire mcf54418, using DSPI_DMA_MODE mode, spi transfers
at first boot stage are not succeding:
m25p80 spi0.1: unrecognized JEDEC id bytes: 00, 00, 00
The reason is the SPI_SR initial value set by the driver, that
is not clearing (not setting to 1) the RF_DF flag. After a tour
on the dspi hw modules that use this driver(Vybrid, ColdFire and
ls1021a) a better init value for SR register has been set.
Signed-off-by: Angelo Dureghello <angelo@sysam.it>
Signed-off-by: Mark Brown <broonie@kernel.org>
This driver is derived from the SPI NOR driver at
mtd/spi-nor/fsl-quadspi.c. It uses the new SPI memory interface
of the SPI framework to issue flash memory operations to up to
four connected flash chips (2 buses with 2 CS each).
The controller does not support generic SPI messages.
This patch also disables the build of the "old" driver and reuses
its Kconfig option CONFIG_SPI_FSL_QUADSPI to replace it.
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Acked-by: Han Xu <han.xu@nxp.com>
Reviewed-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Tested-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Tested-by: Han Xu <han.xu@nxp.com>
Reviewed-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Remove Reset operation in fsl_lpspi_config(). This RST may cause both CLK
and CS pins go from high to low level under cs-gpio mode.
Add fsl_lpspi_reset() function after one message transfer to clear all
flags in use.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add judgment on SR_MBF and FSR_RXCOUNT.
In PIO mode, if don't use CONT to keep cs selected in one transfer, the
transfer will go wrong. FCIE will be set after one frame transfer
finish. If use CONT, the frame refer to the whole data in one transfer.
If don't use CONT, the frame refer to one byte of whole data. This will
cause the transfer ending early.
This patch add a register reading in isr function, it might lead to a
slight decrease in the max transmission speed in PIO mode.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use SR_TDF to judge if need to send data, and SR_FCF is to judge if
transmission end and to replace the waiting after transmission end.
This waiting has no actual meaning, for module will set the FCF
flag at the real end.
The changes of interrupt flag and ISR function reduce the times of
calling ISR. The use of the FCF flag improves the stability of the
data transmission. These two points generally improve the data
transfer speed of lpspi, especially when it is set to slave mode
it can support higher transfer speed of the host.
After making these changes, there is no need to use
fsl_lpspi_txfifo_empty(), so remove it.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In npcm_pspi_probe(), current code set platform_set_drvdata(pdev, master);
so in npcm_pspi_remove() platform_get_drvdata(pdev) will return pointer to
master rather than priv. Fix it.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The main thing this release has been a lot of work on the integration
with SPI NOR flashes, there's been some specific support for a while for
controller features designed to make them perform better but it's not
worked out as well as hoped so the interface has been redesigned in a
way that will hopefully do better - it's already been adopted by a
number of additional controllers so things are looking good. Otherwise
most of the work has been driver specific:
- Support for better integration with NOR flashes from Boris Brezillon
and Yogesh Narayan Gaur plus usage of it in several drivers.
- A big cleanup of the Rockchip driver from Emil Renner Berthing.
- Lots of performance improvements for bcm2835 from Lukas Wunner.
- Slave mode support for pxa2xx from Lubomir Rintel.
- Support for Macronix MXIC, Mediatek MT7629 and MT8183, NPCM PSPI,
and Renesas r8a77470.
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Merge tag 'spi-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"The main thing this release has been a lot of work on the integration
with SPI NOR flashes, there's been some specific support for a while
for controller features designed to make them perform better but it's
not worked out as well as hoped so the interface has been redesigned
in a way that will hopefully do better - it's already been adopted by
a number of additional controllers so things are looking good.
Otherwise most of the work has been driver specific:
- Support for better integration with NOR flashes from Boris
Brezillon and Yogesh Narayan Gaur plus usage of it in several
drivers.
- A big cleanup of the Rockchip driver from Emil Renner Berthing.
- Lots of performance improvements for bcm2835 from Lukas Wunner.
- Slave mode support for pxa2xx from Lubomir Rintel.
- Support for Macronix MXIC, Mediatek MT7629 and MT8183, NPCM PSPI,
and Renesas r8a77470"
* tag 'spi-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (90 commits)
spi: sh-msiof: Reduce the number of times write to and perform the transmission from FIFO
spi: sh-msiof: Add r8a774c0 support
doc: lpspi: Document DT bindings for LPSPI slave mode
spi: lpspi: Let watermark change with send data length
spi: lpspi: Add slave mode support
spi: lpspi: Replace all "master" with "controller"
spi: imx: drop useless member speed_hz from driver data struct
spi: imx: rename config callback and add useful parameters
spi: imx: style fixes
spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.
spi: imx: add a device specific prepare_message callback
mtd: atmel-quadspi: disallow building on ebsa110
spi: Update NPCM PSPI controller documentation
spi: npcm: Modify pspi send function
spi: Use of_node_name_eq for node name comparisons
spi: dw-mmio: add ACPI support
spi: bcm2835: Synchronize with callback on DMA termination
spi: bcm2835: Speed up FIFO access if fill level is known
spi: bcm2835: Polish transfer of DMA prologue
spi: spi-mem: add support for octal mode I/O data transfer
...
The current state of the spi-sh-msiof, in master transfer mode: if t-> bits_per_word <= 8,
if the data length is divisible by 4 ((len & 3) = 0), the length of each word will be 32 bits
In case of data length can not be divisible by 4 ((len & 3) != 0), always set each word to be
8 bits, this will increase the number of times that write to FIFO, increasing the number of
times it should be transmitted. Assume that the number of bytes of data length more than 64 bytes,
each transmission will write 64 times into the TFDR then transmit, a maximum one-time
transmission will transmit 64 bytes if each word is 8 bits long.
Switch to setting if t->bits_per_word <= 8, the word length will be 32 bits although the data
length is not divisible by 4, then if leftover, will transmit the balance and the length of each
words is 1 byte. The maximum each can transmit up to 64 x 4 (Data Size = 32 bits (4 bytes)) = 256 bytes.
TMDR2 : Bits 28 to 24 BITLEN1[4:0] Data Size (8 to 32 bits)
Bits 23 to 16 WDLEN1[7:0] Word Count (1 to 64 words)
Signed-off-by: Hoan Nguyen An <na-hoan@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
Configure watermark to change with the length of the sent data.
Support LPSPI sending message shorter than tx/rxfifosize.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add slave mode support to the fsl-lpspi driver, only in PIO mode.
For now, there are some limitations for slave mode transmission:
1. The stale data in RXFIFO will be dropped when the Slave does any new
transfer.
2. One transfer can be finished only after all transfer->len data been
transferred to master device
3. Slave device only accepts transfer->len data. Any data longer than
this from master device will be dropped. Any data shorter than this
from master will cause LPSPI to stuck due to mentioned limitation 2.
4. Only PIO transfer is supported in Slave Mode.
Wire connection:
GND, SCK, MISO(to MISO of slave), MOSI(to MOSI of slave), SCS
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In order to enable the slave mode and make the code more readable,
replace all related structure names and object names which is
named "master" with "controller".
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver data's member variable just caches the transfer's speed_hz
member. All users of the former now have access directly to the latter.
So fix them to use the uncached value and remove the cache.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The config callback is called once per transfer while some things can (and
should) be done on a per message manner. To have unambiguous naming in the
end include "transfer" in the callback's name and rename the
implementations accordingly. Also pass the driver struct and transfer
which allows further simplifications in the following patch.
There is no change in behavior intended here.
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
This change fixes some random style issues that I noticed while debugging
the driver: Remove some double spaces, use tabs for indention instead
of spaces if possible, fix comment style.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The relevant difference between prepare_message and config is that the
former is run before the CS signal is asserted. So the polarity of the
CLK line must be configured in prepare_message as an edge generated by
config might already result in a latch of the MOSI line.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
This is just preparatory work which allows to move some initialisation
that currently is done in the per transfer hook .config to an earlier
point in time in the next few patches. There is no change in behaviour
introduced by this patch.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
I ran into a link-time error with the atmel-quadspi driver on the
EBSA110 platform:
drivers/mtd/built-in.o: In function `atmel_qspi_run_command':
:(.text+0x1ee3c): undefined reference to `_memcpy_toio'
:(.text+0x1ee48): undefined reference to `_memcpy_fromio'
The problem is that _memcpy_toio/_memcpy_fromio are not available on
that platform, and we have to prevent building the driver there.
In case we want to backport this to older kernels: between linux-4.8
and linux-4.20, the Kconfig entry was in drivers/mtd/spi-nor/Kconfig
but had the same problem.
Link: https://lore.kernel.org/patchwork/patch/812860/
Fixes: 161aaab8a0 ("mtd: atmel-quadspi: add driver for Atmel QSPI controller")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Align pspi send function code with the recieve function
code, Also simplify the code a bit with early return.
Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The Hisilicon Hip08 platform, that uses ACPI, has this controller.
Let's add ACPI support for DW SPI MMIO-based host.
The ACPI ID used is "HISI0173" for the Designware SPI controller of
Hisilicon Hip08 platform.
Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit b36f09c3c4 ("dmaengine: Add transfer termination
synchronization support") deprecated dmaengine_terminate_all() in favor
of dmaengine_terminate_sync() and dmaengine_terminate_async() to avoid
freeing resources used by the DMA callback before its execution has
concluded.
Commit de92436ac4 ("dmaengine: bcm2835-dma: Use vchan_terminate_vdesc()
instead of desc_free") amended the BCM2835 DMA driver with an
implementation of ->device_synchronize(), which is a prerequisite for
dmaengine_terminate_sync(). Thus, clients of the DMA driver (such as
the BCM2835 SPI driver) may now be converted to the new API.
It is generally desirable to use the _sync() variant except in atomic
context. There is only a single occurrence where the BCM2835 SPI driver
calls dmaengine_terminate_all() in atomic context and that is in
bcm2835_spi_dma_done() (the RX DMA channel's callback) to terminate the
TX DMA channel. The TX DMA channel doesn't have a callback (yet), hence
it is safe to use the _async() variant there.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The RX and TX FIFO of the BCM2835 SPI master each accommodate 64 bytes
(16 32-bit dwords). The CS register provides hints on their fill level:
"Bit 19 RXR - RX FIFO needs Reading ([¾] full)
0 = RX FIFO is less than [¾] full (or not active TA = 0).
1 = RX FIFO is [¾] or more full. Cleared by reading sufficient
data from the RX FIFO or setting TA to 0."
"Bit 16 DONE - Transfer Done
0 = Transfer is in progress (or not active TA = 0).
1 = Transfer is complete. Cleared by writing more data to the
TX FIFO or setting TA to 0."
"If DONE is set [...], write up to 16 [dwords] to SPI_FIFO. [...]
If RXR is set read 12 [dwords] data from SPI_FIFO."
[Source: Pages 153, 154 and 158 of
https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
Note: The spec is missing the "¾" character, presumably due to
copy-pasting from a different charset. It also incorrectly
refers to 16 and 12 "bytes" instead of 32-bit dwords.]
In short, the RXR bit indicates that 48 bytes can be read and the DONE
bit indicates 64 bytes can be written. Leverage this knowledge to read
or write bytes blindly to the FIFO, without polling whether data can be
read or free space is available to write. Moreover, when a transfer is
starting, the TX FIFO is known to be empty, likewise allowing a blind
write of 64 bytes.
This cuts the number of bus accesses in half if the fill level is known.
Also, the (posted) write accesses can be pipelined on the AXI bus since
they are no longer interleaved with (non-posted) reads.
bcm2835_spi_transfer_one_poll() switches to interrupt mode when a time
limit is exceeded by calling bcm2835_spi_transfer_one_irq(). The TX
FIFO may contain data in this case, but is known to be empty when the
function is called from bcm2835_spi_transfer_one(). Hence only blindly
fill the TX FIFO in the latter case but not the former.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Eric Anholt <eric@anholt.net>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 3bd7f6589f ("spi: bcm2835: Overcome sglist entry length
limitation") was unfortunately merged even though submission of a
refined version was imminent. Apply those refinements as an amendment:
* Drop no longer needed #include <asm/page.h>. The lines requiring
its inclusion were removed by the commit.
* Change type of tx_spillover flag from bool to unsigned int for
consistency with dma_pending flag and pursuant to Linus' dictum:
https://lkml.org/lkml/2017/11/21/384
* In bcm2835_rd_fifo_count() do not check for bs->rx_buf != NULL.
The function will never be called if that's the case.
* Amend kerneldoc of bcm2835_wait_tx_fifo_empty() to prevent its use in
situations where the function might spin forever. (In response to a
review comment by Stefan Wahren.)
* Sync only the cacheline containing the RX prologue back to memory,
not the full first sglist entry.
* Use sg_dma_address() and sg_dma_len() instead of referencing the
sglist entry members directly. Seems to be the more common syntax in
the tree, even for lvalues.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for octal mode I/O data transfer in spi-mem framework.
Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add flags for Octal mode I/O data transfer
Required for the SPI controller which can do the data transfer (TX/RX)
on 8 data lines e.g. NXP FlexSPI controller.
SPI_TX_OCTAL: transmit with 8 wires
SPI_RX_OCTAL: receive with 8 wires
Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix build errors when CONFIG_PINCTRL is not enabled.
The header file <linux/pinctrl/consumer.h> handles both CONFIG_PINCTRL
enabled and disabled cases.
CC [M] drivers/spi/spi-at91-usart.o
../drivers/spi/spi-at91-usart.c: In function 'at91_usart_spi_runtime_suspend':
../drivers/spi/spi-at91-usart.c:409:2: error: implicit declaration of function 'pinctrl_pm_select_sleep_state' [-Werror=implicit-function-declaration]
pinctrl_pm_select_sleep_state(dev);
../drivers/spi/spi-at91-usart.c: In function 'at91_usart_spi_runtime_resume':
../drivers/spi/spi-at91-usart.c:419:2: error: implicit declaration of function 'pinctrl_pm_select_default_state' [-Werror=implicit-function-declaration]
pinctrl_pm_select_default_state(dev);
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Radu Pirea <radu.pirea@microchip.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit e82b0b3828 ("spi: bcm2835: Fix race on DMA termination") broke
the build with COMPILE_TEST=y on arches whose cmpxchg() requires 32-bit
operands (xtensa, older arm ISAs).
Fix by changing the dma_pending flag's type from bool to unsigned int.
Fixes: e82b0b3828 ("spi: bcm2835: Fix race on DMA termination")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
A few driver specific fixes here, nothing big or that stands out for
anyone other than the driver users.
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Merge tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A few driver specific fixes here, nothing big or that stands out for
anyone other than the driver users.
The omap2-mcspi fix is for issues that started showing up with a
change in defconfig in this release to make cpuidle get turned on by
default"
* tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: omap2-mcspi: Add missing suspend and resume calls
spi: mediatek: use correct mata->xfer_len when in fifo transfer
spi: uniphier: fix incorrect property items
When in DMA mode, the BCM2835 SPI controller requires that the FIFO is
accessed in 4 byte chunks. This rule is not fulfilled if a transfer
consists of multiple sglist entries, one per page, and the first entry
starts in the middle of a page with an offset not a multiple of 4.
The driver currently falls back to programmed I/O for such transfers,
incurring a significant performance penalty.
Overcome this hardware limitation by transferring the first few bytes of
a transfer without DMA such that the remainder of the first sglist entry
becomes a multiple of 4. Specifics are provided in kerneldoc comments.
An alternative approach would have been to split transfers in the
->prepare_message hook, but this may necessitate two transfers per page,
defeating the goal of clustering multiple pages together in a single
transfer for efficiency. E.g. if the first TX sglist entry's length is
23 and the first RX's is 40, the first transfer would send and receive
23 bytes, the second 40 - 23 = 17 bytes, the third 4096 - 17 = 4079
bytes, the fourth 4096 - 4079 = 17 bytes and so on. In other words,
O(n) transfers are necessary (n = number of sglist entries), whereas
the algorithm implemented herein only requires O(1) additional work.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Document the driver's data structure to lower the barrier to entry for
contributors.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit a30a555d74 ("spi: bcm2835: transform native-cs to gpio-cs on
first spi_setup") disabled the use of hardware-controlled native Chip
Select in favour of software-controlled GPIO Chip Select but left code
to support the former untouched. Remove it to simplify the driver and
ease the addition of new features and further optimizations.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
If a DMA transfer finishes orderly right when spi_transfer_one_message()
determines that it has timed out, the callbacks bcm2835_spi_dma_done()
and bcm2835_spi_handle_err() race to call dmaengine_terminate_all(),
potentially leading to double termination.
Prevent by atomically changing the dma_pending flag before calling
dmaengine_terminate_all().
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Fixes: 3ecd37edaa ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Cc: stable@vger.kernel.org # v4.2+
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
If submission of a DMA TX transfer succeeds but submission of the
corresponding RX transfer does not, the BCM2835 SPI driver terminates
the TX transfer but neglects to reset the dma_pending flag to false.
Thus, if the next transfer uses interrupt mode (because it is shorter
than BCM2835_SPI_DMA_MIN_LENGTH) and runs into a timeout,
dmaengine_terminate_all() will be called both for TX (once more) and
for RX (which was never started in the first place). Fix it.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Fixes: 3ecd37edaa ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Cc: stable@vger.kernel.org # v4.2+
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The IRQ handler bcm2835_spi_interrupt() first reads as much as possible
from the RX FIFO, then writes as much as possible to the TX FIFO.
Afterwards it decides whether the transfer is finished by checking if
the TX FIFO is empty.
If very few bytes were written to the TX FIFO, they may already have
been transmitted by the time the FIFO's emptiness is checked. As a
result, the transfer will be declared finished and the chip will be
reset without reading the corresponding received bytes from the RX FIFO.
The odds of this happening increase with a high clock frequency (such
that the TX FIFO drains quickly) and either passing "threadirqs" on the
command line or enabling CONFIG_PREEMPT_RT_BASE (such that the IRQ
handler may be preempted between filling the TX FIFO and checking its
emptiness).
Fix by instead checking whether rx_len has reached zero, which means
that the transfer has been received in full. This is also more
efficient as it avoids one bus read access per interrupt. Note that
bcm2835_spi_transfer_one_poll() likewise uses rx_len to determine
whether the transfer has finished.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Fixes: e34ff011c7 ("spi: bcm2835: move to the transfer_one driver model")
Cc: stable@vger.kernel.org # v4.1+
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch implements power management callback function for USART as
SPI driver.
Signed-off-by: Radu Pirea <radu_nicolae.pirea@upb.ro>
Signed-off-by: Mark Brown <broonie@kernel.org>
The compiler has no way to know that rsize 1 or 2 are the only valid
values. Also simplify the code a bit with early return.
The warning was:
drivers/spi/spi-npcm-pspi.c:215:6: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is an IS_ERR() vs PTR_ERR() typo here. The current code returns 1
but we want to return the negative error code.
Fixes: 2a22f1b30c ("spi: npcm: add NPCM PSPI controller driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Address remaining comments from original driver patch series
* Move RD_FIFO_CFG to be ordered corretly
* Expand spinlock comment
Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Most modern SPI controllers can directly map a SPI memory (or a portion
of the SPI memory) in the CPU address space. Most of the time this
brings significant performance improvements as it automates the whole
process of sending SPI memory operations every time a new region is
accessed.
This new API allows SPI memory drivers to create direct mappings and
then use them to access the memory instead of using spi_mem_exec_op().
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The logic surrounding the ->exec_op() call applies to direct mapping
accessors. Move this code to separate functions to avoid duplicating
code.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When defining spi_mem_op templates we don't necessarily know the size
that will be passed when the template is actually used, and basing the
supports_op() check on op->data.nbytes to know whether there will be
data transferred for a specific operation is this not possible.
Add SPI_MEM_NO_DATA to the spi_mem_data_dir enum so that we can base
our checks on op->data.dir instead of op->data.nbytes.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
I've been wondering still about omap2-mcspi related suspend and resume
flakeyness and looks like we're missing calls to spi_master_suspend()
and spi_master_resume(). Adding those and using pm_runtime_force_suspend()
and pm_runtime_force_resume() makes things work for suspend and resume
and allows us to stop using noirq suspend and resume.
And while at it, let's use SET_SYSTEM_SLEEP_PM_OPS to simplify things
further.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The refactoring done as part of adding the core support for handling
waiting for slave transfer dropped a conditional which meant that we
started waiting for completion of all transfers, not just those that the
controller asked for. This caused hangs and massive delays on platforms
that don't need the core delay. Re-add the delay to fix this.
Fixes: 810923f3bf (spi: Deal with slaves that return from transfer_one() unfinished)
Reported-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-npcm-pspi.c:470:3-8: No need to set .owner here. The core will do it.
Remove .owner field if calls are used which set it automatically
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Fixes: 2a22f1b30c ("spi: npcm: add NPCM PSPI controller driver")
CC: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The license text is specifying GPL v2 or later but the MODULE_LICENSE
is set to GPL v2 which means GNU Public License v2 only. So choose the
license text as the correct one.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Kauer <florian.kauer@koalo.de>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The u32 variable csgpio is being checked for an error return
from the call to of_get_named_gpio, however, since this is unsigned
this comparison will always be false. Fix this by making csgpio an
int and fix up the %u format specifiers to %d accordingly.
Detected by CoverityScan, CID#1475476 ("Unsigned compared against 0")
Fixes: 2a22f1b30c ("spi: npcm: add NPCM PSPI controller driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Do not deselect cs when cs_change is set for the last transfer in the
message. In this case, cs_change indicates that cs should stay selected
until the next transfer.
Signed-off-by: Fredrik Ternerot <fredrikt@axis.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There doesn't seem to be a way to empty TXFIFO on MMP2. The datasheet is
super-secret and the method described in Armada 16x manual won't work:
"The TXFIFO and RXFIFO are cleared to 0b0 when the SSPx port is reset or
disabled (by writing a 0b0 to the <Synchronous Serial Port Enable> field
in the SSP Control Register 0)."
# devmem 0xd4037008 # read SSSR
0x0000F204
# devmem 0xd4037000 32 0x07 # SSE off in SSCR0
# devmem 0xd4037000 32 0x87 # SSE on
# devmem 0xd4037008
0x0000F204
^ TXFIFO level is still 2. Sigh.
The OLPC 1.75 boot firmware leaves two bytes in the TXFIFO. Those are
basically throwaway bytes used in response to the messages from the EC.
The OLPC kernel copes with this by power-cycling the hardware. Perhaps
the firmware should do this instead.
Other than that, there's not much we can do other than complain loudly
until the garbage gets drained and discard the actual data... For the
OLPC EC this will work just fine and pushing more data to TXFIFO would
break further transactions.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
Strobe a GPIO line when the slave TX FIFO is filled. This is how the
Embedded Controller on an OLPC XO-1.75 machine, that happens to be a SPI
master, learns that it can initiate a transaction.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Tested on an OLPC XO-1.75 machine, where the Embedded Controller happens
to be a SPI master.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some drivers, such as spi-pxa2xx return from the transfer_one callback
immediately, idicating that the transfer will be finished asynchronously.
Normally, spi_transfer_one_message() synchronously waits for the
transfer to finish with wait_for_completion_timeout(). For slaves, we
don't want the transaction to time out as it can complete in a long time
in future. Use wait_for_completion_interruptible() instead.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some devices such as the TPO TPG110 display panel require
a "high-impedance turn-around", in effect a clock cycle after
switching the line from output to input mode.
Support this in the GPIO driver to begin with. Other driver
may implement it if they can, it is unclear if this can
be achieved with anything else than GPIO bit-banging.
Cc: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Enable McSPI driver to be built for K3 platforms, to support McSPI on
AM654 SoC of K3 family.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Kernel contains QSPI driver strongly tied to MTD and nor-flash memory.
New spi-mem interface allows usage also other memory types, especially
much larger NAND with SPI interface. This driver works as SPI controller
and is not related to MTD, however can work with NAND-flash or other
peripherals using spi-mem interface.
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Piotr Bugalski <bugalski.piotr@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add a driver for Macronix SPI controller IP.
Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We should get 'driver_data' from 'struct device' directly. Going via
platform_device is an unneeded step back and forth.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We should get 'driver_data' from 'struct device' directly. Going via
platform_device is an unneeded step back and forth.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
We should get 'driver_data' from 'struct device' directly. Going via
platform_device is an unneeded step back and forth.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Re-arrange existing APIs in probe function to
avoid using goto and remove redundant variables.
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
fixed the nitpicks.
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some SoC share one irq number between DSPI controllers.
For example, on the LX2160 board, DSPI0 and DSPI1 share one irq number.
In this case, only one DSPI controller can register successfully,
and others will fail.
Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Intel LPSS private register restoring in spi-pxa2xx.c: pxa2xx_spi_resume()
was added before there was no any other code restoring them. This was
changed after following commits for previous and current LPSS platforms:
c78b083066 ("ACPI / LPSS: custom power domain for LPSS")
41a3da2b8e ("mfd: intel-lpss: Save register context on suspend")
However there is one caveat: There is no LPSS private register context
save/restore for the Intel Lynxpoint in the Linux kernel code.
I did some debugging on one Lynxpoint based device I have and on it the
LPSS register context is not lost over suspend/resume cycle (s2idle).
Which happens for instance on Intel Braswell. I'm speculating but I guess
either firmware does it or the LPSS is kept always on Lynxpoint.
Given that we haven't needed to implement Lynxpoint LPSS I2C or UART
private register context save/restore over four years time I think we are
safe to remove this LPSS private register restoring during resume here.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add missing support for lsb-first mode.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The hardware supports 4, 8 and 16bit spi words,
so add the missing support for 4bit words.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Register an interrupt handler to fill/empty the
tx and rx fifos rather than busy-looping.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now that we no longer potentially change spi clock
at runtime we can precompute the rx sample delay
at probe time rather than for each transfer.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver previously checked each transfer if the
requested speed was higher than possible with the
current spi clock rate and raised the clock rate
accordingly.
However, there is no check to see if the spi clock
was actually set that high and no way to dynamically
lower the spi clock rate again.
So it seems any potiential users of this functionality
are better off just setting the spi clock rate at init
using the assigned-clock-rates devicetree property.
Removing this dynamic spi clock rate raising allows
us let the spi framework handle min/max speeds
for us.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
We only need to know if we're using dma when setting
up the transfer, so just use a local variable for
that.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
In almost all cases we already have a pointer to the
spi master structure where we have the driver data.
The only exceptions are the dma callbacks which are
easily fixed by passing them the master and using
spi_master_get_devdata to retrieve the driver data.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi master (aka spi controller) structure already
has two fields for storing the rx and tx dma channels.
Just use them rather than duplicating them in driver data.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Just read transfer info directly from the spi device
and transfer structures rather than storing it in
driver data first.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Successful transfers leave the spi disabled, so if
we just make sure to disable the spi on error
there should be no need to disable the spi from
master->unprepare_message.
This also flushes the tx and rx fifos,
so no need to do that manually.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The state field is currently only used to make sure
only the last of the tx and rx dma callbacks issue
an spi_finalize_current_transfer.
Rather than using a spinlock we can get away
with just turning the state field into an atomic_t.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The hardware supports 3 different variants of SPI
and there were some code around it, but nothing
to actually set it to anything but "Motorola SPI".
Just drop that code and always use that mode.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use C99 designated initializers for dma slave config
structures. This also makes sure uninitialized fields
are zeroed so we don't need an explicit memset.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi_enable_chip function takes a boolean
argument. Change the type to reflect that.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
when xfer_len is greater than 64 bytes and use fifo mode
to transfer, the actual length from the third time is mata->xfer_len
but not len in mtk_spi_interrupt().
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
ARM-based 63xx DSL platforms have the spi-bcm63xx-hsspi controller
present, allow using this driver there as well.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support to use McSPI controller as SPI slave. In slave mode, DMA TX
completion does not mean entire data has been shifted out as data might
still be stuck in FIFO waiting for master to clock the bus. Therefore,
add an IRQ handler for slave mode to know when entire data in FIFO has
been shifted out.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
McSPI has 32 byte FIFO in Transmit-Receive mode. Current code tries to
configuration FIFO watermark level for DMA trigger to be GCD of transfer
length and max FIFO size which would mean trigger level may be set to 32
for transmit-receive mode if length is aligned. This does not work in
case of SPI slave mode where FIFO always needs to have data ready
whenever master starts the clock. With DMA trigger size of 32 there will
be a small window during slave TX where DMA is still putting data into
FIFO but master would have started clock for next byte, resulting in
shifting out of stale data. Similarly, on Slave RX side there may be RX
FIFO overflow
Fix this by setting FIFO watermark for DMA trigger to word
length. This means DMA is triggered as soon as FIFO has space for word
length bytes and DMA would make sure FIFO is almost always full
therefore improving FIFO occupancy in both master and slave mode.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use standard readl_poll_timeout() macro for polling on status bits.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The qspi controller is a specialized communication interface
targeting single, dual or quad SPI Flash memories (NOR/NAND).
It can operate in any of the following modes:
-indirect mode: all the operations are performed using the quadspi
registers
-read memory-mapped mode: the external Flash memory is mapped to the
microcontroller address space and is seen by the system as if it was
an internal memory
tested on:
-NOR: mx66l51235l
-NAND: MT29F2G01ABAGD
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The DMA API does its own zone decisions based on the coherent_dma_mask.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit 9ec36cafe4 ("of/irq: do irq resolution in platform_get_irq")
platform_get_irq() can return -EPROBE_DEFER. However, the driver overrides
an error returned by that function with -ENOENT which breaks the deferred
probing. Propagate upstream an error code returned by platform_get_irq()
and remove the bogus "platform" from the error message, while at it...
Fixes: 9ec36cafe4 ("of/irq: do irq resolution in platform_get_irq")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use PIO mode instead if size is smaller than fifo size, since
dma may be less efficient.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Correct wml as the last rx sg length instead of the whole transfer
length. Otherwise, mtd_stresstest will be failed as below:
insmod mtd_stresstest.ko dev=0
=================================================
mtd_stresstest: MTD device: 0
mtd_stresstest: not NAND flash, assume page size is 512 bytes.
mtd_stresstest: MTD device size 4194304, eraseblock size 65536, page size 512, count of eraseblocks 64, pa0
mtd_stresstest: doing operations
mtd_stresstest: 0 operations done
mtd_test: mtd_read from 1ff532, size 880
mtd_test: mtd_read from 20c267, size 64998
spi_master spi0: I/O Error in DMA RX
m25p80 spi0.0: SPI transfer failed: -110
spi_master spi0: failed to transfer one message from queue
mtd_test: error: read failed at 0x20c267
mtd_stresstest: error -110 occurred
=================================================
insmod: ERROR: could not insert module mtd_stresstest.ko: Connection timed out
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Current dynamic burst length is based on the whole transfer length,
that's ok if there is only one sg, but is not right in case multi sgs
in one transfer,because the tail data should be based on the last sg
length instead of the whole transfer length. Move wml setting for DMA
to the later place, thus, the next patch could get the right last sg
length for wml setting. This patch is a preparation one, no any
function change involved.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPI configuration state includes an SPI_NO_CS flag that disables
all CS line manipulation, for applications that want to manage their
own chip selects. However, this flag is ignored by the GPIO CS code
in the SPI framework.
Correct this omission with a trivial patch.
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The MMP2 platform, that uses device tree, has this controller. Let's add
devicetree alongside platform & PCI.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Mark Brown <broonie@kernel.org>
This driver supports GENI based SPI Controller in the Qualcomm SOCs. The
Qualcomm Generic Interface (GENI) is a programmable module supporting a
wide range of serial interfaces including SPI. This driver supports SPI
operations using FIFO mode of transfer.
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>
Signed-off-by: Dilip Kota <dkota@codeaurora.org>
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Let the dma/non-dma code paths handle the spi enable
flag themselves. This removes some logic to determine
if the flag should be turned on before or after dma
and also don't leave the spi enabled if the dma path
fails.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dma direction for the tx and rx dma channels never
change, so just use the constants directly rather
than storing them in device data.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver data has a u32 field use_dma which is
only ever used as a boolean, so change its type
to reflect that.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
We no longer need the dma_caps since the dma driver
already clamps the burst length to the hardware limit,
so don't request and store dma_caps in device data.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signal tx dma when spi fifo is less than half full,
and limit tx bursts to half the fifo length.
Clamp rx burst length to 1 to avoid alignment issues.
Signed-off-by: Huibin Hong <huibin.hong@rock-chips.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
The rxconf and txconf structs are allocated on the
stack, so make sure we zero them before filling out
the relevant fields.
Signed-off-by: Huibin Hong <huibin.hong@rock-chips.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
New driver for Qualcomm QuadSPI(QSPI) controller that is used to
communicate with slaves such as flash memory devices. The QSPI controller
can operate in 2 or 4 wire mode but only supports SPI Mode 0. The
controller can also operate in Single or Dual data rate modes.
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>
Signed-off-by: Ryan Case <ryandcase@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for a new devicetree compatible string called
'amazon,alpine-apb-ssi', which is necessary for the Amazon Alpine spi
controller. 'amazon,alpine-dw-apb-ssi' is used in the dw spi driver if
specified in the devicetree. Otherwise, fall back to driver default
behavior, i.e. original dw IP hw driver behavior.
Signed-off-by: Talel Shenhar <talel@amazon.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixing/optimizing bcm_qspi_bspi_read() performance introduced two
changes:
1) It added a loop to read all requested data using multiple BSPI ops.
2) It bumped max size of a single BSPI block request from 256 to 512 B.
The later change resulted in occasional BSPI timeouts causing a
regression.
For some unknown reason hardware doesn't always handle reads as expected
when using 512 B chunks. In such cases it may happen that BSPI returns
amount of requested bytes without the last 1-3 ones. It provides the
remaining bytes later but doesn't raise an interrupt until another LR
start.
Switching back to 256 B reads fixes that problem and regression.
Fixes: 345309fa7c ("spi: bcm-qspi: Fix bcm_qspi_bspi_read() performance")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
During implementation of the new API bcm_qspi_bspi_set_flex_mode() has
been modified breaking calculation of address length. An unnecessary
multiplication was added breaking flash reads.
Fixes: 5f195ee7d8 ("spi: bcm-qspi: Implement the spi_mem interface")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
spidev will make a big fuss if a device tree node binds a device by
using "spidev" as the node's compatible property.
However, the logic for this isn't looking for "spidev" in the
compatible, but rather checking that the device is NOT compatible with
spidev's list of devices.
This causes a false positive if a device not named "rohm,dh2228fv", etc.
binds to spidev, even if a means other than putting "spidev" in the
device tree was used. E.g., the sysfs driver_override attribute.
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Tested-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
This attribute works the same was as the identically named attribute
for PCI, AMBA, and platform devices. For reference, see:
commit 3cf3857134 ("ARM: 8256/1: driver coamba: add device binding
path 'driver_override'")
commit 3d713e0e38 ("driver core: platform: add device binding path
'driver_override'")
commit 782a985d7a ("PCI: Introduce new device binding path using
pci_dev.driver_override")
If the name of a driver is written to this attribute, then the device
will bind to the named driver and only the named driver.
The device will bind to the driver even if the driver does not list the
device in its id table. This behavior is different than the driver's
bind attribute, which only allows binding to devices that are listed as
supported by the driver.
It can be used to bind a generic driver, like spidev, to a device.
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Tested-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Silvio Cesare
Lanqing Liu
Vignesh R
Charles Keepax
Stephen Boyd
Linus Walleij
Anders Roxell
Martin Sperl
Luis Chamberlain
Cezary Gapinski
shaftarger
Angelo Dureghello
Frieder Schrempf
Clark Wang
Mark Brown
Axel Lin
Linus Torvalds
Hoan Nguyen An
Uwe Kleine-König
Arnd Bergmann
Tomer Maimon
Rob Herring
Jay Fang
Lukas Wunner
Yogesh Narayan Gaur
Randy Dunlap
Leilk Liu
Radu Pirea
Olof Johansson
Dan Carpenter
Ryan Case
Boris Brezillon
Lubomir Rintel
Tony Lindgren
kbuild test robot
Stefan Wahren
Colin Ian King
Fredrik Ternerot
Piotr Bugalski
Mason Yang
Wolfram Sang
Alok Chauhan
Chuanhua Han
Jarkko Nikula
Emil Renner Berthing
Florian Fainelli
Ludovic Barre
Christoph Hellwig
Sergei Shtylyov
Robin Gong
Phil Elwell
Girish Mahadevan
Huibin Hong
Talel Shenhar
Rafał Miłecki
Trent Piepho