In pch_spi_handle_dma, it doesn't check for NULL returns of kcalloc
so it would result in an Oops.
Fixes: c37f3c2749 ("spi/topcliff_pch: DMA support")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dirmap descriptor object allocated in spi_mem_dirmap_create is
never freed. Add a kfree(desc) in spi_mem_dirmap_destroy().
Fixes: aa167f3fed ("spi: spi-mem: Add a new API to support direct mapping")
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
spi_mem_dirmap_destroy() takes a single argument, remove the @info entry
in the doc.
Fixes: aa167f3fed ("spi: spi-mem: Add a new API to support direct mapping")
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
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>
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>
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>
