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.
See: https://github.com/raspberrypi/linux/issues/2169
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
The spi-bcm2835 driver automatically uses GPIO chip-selects due to
some unreliability of the native ones. In doing so it chooses the
same pins as the native chip-selects would use, but the existing
code always uses pins 7 and 8, wherever the SPI function is mapped.
Search the pinctrl group assigned to the driver for pins that
correspond to native chip-selects, and use those for GPIO chip-
selects.
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
commit ef070b4e4a upstream.
When the commit b6ced294fb
("spi: pxa2xx: Switch to SPI core DMA mapping functionality")
switches to SPI core provided DMA helpers, it missed to setup maximum
supported DMA transfer length for the controller and thus users
mistakenly try to send more data than supported with the following
warning:
ili9341 spi-PRP0001:01: DMA disabled for transfer length 153600 greater than 65536
Setup maximum supported DMA transfer length in order to make users know
the limit.
Fixes: b6ced294fb ("spi: pxa2xx: Switch to SPI core DMA mapping functionality")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 673c865efb upstream.
Commit 4dea6c9b0b ("spi: spi-ti-qspi: add mmap mode read support") has
has got order of parameter wrong when calling regmap_update_bits() to
select CS for mmap access. Mask and value arguments are interchanged.
Code will work on a system with single slave, but fails when more than
one CS is in use. Fix this by correcting the order of parameters when
calling regmap_update_bits().
Fixes: 4dea6c9b0b ("spi: spi-ti-qspi: add mmap mode read support")
Cc: stable@vger.kernel.org
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 56c1723426 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dbc944115e upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e82b0b3828 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 91b9deefed ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit abf5feef3f ]
There is a logical problem in spi-gpio with host just
assigning a MOSI line and no MISO: this is interpreted
as the host cannot do RX and the host is flagged with
SPI_MASTER_NO_RX.
This is wrong: since GPIO lines can switch direction,
in 3WIRE operation the host will simply reverse the
direction of the GPIO line and start reading from it,
there is even code for doing this in the driver, but
it went unnoticed because it was tested by using a
master with 4 wires but a device using just 3 wires.
Remove the offending flag.
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a1108c7b2e ]
Clang warns when one enumerated type is implicitly converted to another.
drivers/spi/spi-ep93xx.c:342:62: warning: implicit conversion from
enumeration type 'enum dma_transfer_direction' to different enumeration
type 'enum dma_data_direction' [-Wenum-conversion]
nents = dma_map_sg(chan->device->dev, sgt->sgl, sgt->nents, dir);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
./include/linux/dma-mapping.h:428:58: note: expanded from macro
'dma_map_sg'
#define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
~~~~~~~~~~~~~~~~ ^
drivers/spi/spi-ep93xx.c:348:57: warning: implicit conversion from
enumeration type 'enum dma_transfer_direction' to different enumeration
type 'enum dma_data_direction' [-Wenum-conversion]
dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
./include/linux/dma-mapping.h:429:62: note: expanded from macro
'dma_unmap_sg'
#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
~~~~~~~~~~~~~~~~~~ ^
drivers/spi/spi-ep93xx.c:377:56: warning: implicit conversion from
enumeration type 'enum dma_transfer_direction' to different enumeration
type 'enum dma_data_direction' [-Wenum-conversion]
dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
./include/linux/dma-mapping.h:429:62: note: expanded from macro
'dma_unmap_sg'
#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
~~~~~~~~~~~~~~~~~~ ^
3 warnings generated.
dma_{,un}map_sg expect an enum of type dma_data_direction but this
driver uses dma_transfer_direction for everything. Convert the driver to
use dma_data_direction for these two functions.
There are two places that strictly require an enum of type
dma_transfer_direction: the direction member in struct dma_slave_config
and the direction parameter in dmaengine_prep_slave_sg. To avoid using
an explicit cast, add a simple function, ep93xx_dma_data_to_trans_dir,
to safely map between the two types because they are not 1 to 1 in
meaning.
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0976eda791 upstream.
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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 940ec770c2 upstream.
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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mark writes:
"spi: Fixes for v4.19
Quite a few fixes for the Renesas drivers in here, plus a fix for the
Tegra driver and some documentation fixes for the recently added
spi-mem code. The Tegra fix is relatively large but fairly
straightforward and mechanical, it runs on probe so it's been
reasonably well covered in -next testing."
* tag 'spi-fix-v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: spi-mem: Move the DMA-able constraint doc to the kerneldoc header
spi: spi-mem: Add missing description for data.nbytes field
spi: rspi: Fix interrupted DMA transfers
spi: rspi: Fix invalid SPI use during system suspend
spi: sh-msiof: Fix handling of write value for SISTR register
spi: sh-msiof: Fix invalid SPI use during system suspend
spi: gpio: Fix copy-and-paste error
spi: tegra20-slink: explicitly enable/disable clock
Mark writes:
"spi: Fixes for v4.19
As well as one driver fix there's a couple of fixes here which address
issues with the use of IDRs for allocation of dynamic bus numbers,
ensuring that dynamic bus numbers interact well with static bus numbers
assigned via DT and otherwise."
* tag 'spi-fix-v4.19-rc4' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: spi-fsl-dspi: fix broken DSPI_EOQ_MODE
spi: Fix double IDR allocation with DT aliases
spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers
When interrupted, wait_event_interruptible_timeout() returns
-ERESTARTSYS, and the SPI transfer in progress will fail, as expected:
m25p80 spi0.0: SPI transfer failed: -512
spi_master spi0: failed to transfer one message from queue
However, as the underlying DMA transfers may not have completed, all
subsequent SPI transfers may start to fail:
spi_master spi0: receive timeout
qspi_transfer_out_in() returned -110
m25p80 spi0.0: SPI transfer failed: -110
spi_master spi0: failed to transfer one message from queue
Fix this by calling dmaengine_terminate_all() not only for timeouts, but
also for errors.
This can be reproduced on r8a7991/koelsch, using "hd /dev/mtd0" followed
by CTRL-C.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
If the SPI queue is running during system suspend, the system may lock
up.
Fix this by stopping/restarting the queue during system suspend/resume,
by calling spi_master_suspend()/spi_master_resume() from the PM
callbacks. In-kernel users will receive an -ESHUTDOWN error while
system suspend/resume is in progress.
Based on a patch for sh-msiof by Gaku Inami.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch changes writing to the SISTR register according to the H/W
user's manual.
The TDREQ bit and RDREQ bits of SISTR are read-only, and must be written
their initial values of zero.
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: reword]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
If the SPI queue is running during system suspend, the system may lock
up.
Fix this by stopping/restarting the queue during system suspend/resume
by calling spi_master_suspend()/spi_master_resume() from the PM
callbacks. In-kernel users will receive an -ESHUTDOWN error while
system suspend/resume is in progress.
Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com>
Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
[geert: Cleanup, reword]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This fixes an embarrassing copy-and-paste error in the
errorpath of spi_gpio_request(): we were checking the wrong
struct member for error code right after retrieveing the
sck GPIO.
Fixes: 9b00bc7b90 ("spi: spi-gpio: Rewrite to use GPIO descriptors")
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Depending on the SPI instance one may get an interrupt storm upon
requesting resp. interrupt unless the clock is explicitly enabled
beforehand. This has been observed trying to bring up instance 4 on
T20.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch fixes the dspi_eoq_write function used by the
ColdFire mcf5441x family. The 16 bit cmd part must be re-set at
each data transfer.
Also, now that fifo_size variables are used for eoq_read/write,
a proper fifo size must be set (16 slots for the ColdFire dspi
module version).
Signed-off-by: Angelo Dureghello <angelo@sysam.it>
Acked-by: Esben Haabendal <esben@haabendal.dk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
If the SPI bus number is provided by a DT alias, idr_alloc() is called
twice, leading to:
WARNING: CPU: 1 PID: 1 at drivers/spi/spi.c:2179 spi_register_controller+0x11c/0x5d8
couldn't get idr
Fix this by moving the handling of fixed SPI bus numbers up, before the
DT handling code fills in ctlr->bus_num.
Fixes: 1a4327fbf4 ("spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull hwspinlock updates from Bjorn Andersson:
"This introduces devres helpers and an API to request a lock by name,
then migrates the sprd SPI driver to use these"
* tag 'hwlock-v4.19' of git://github.com/andersson/remoteproc:
hwspinlock: Fix incorrect return pointers
spi: sprd: Change to use devm_hwspin_lock_request_specific()
spi: sprd: Replace of_hwspin_lock_get_id() with of_hwspin_lock_get_id_byname()
hwspinlock: Fix one comment mistake
hwspinlock: Remove redundant config
hwspinlock: Add devm_xxx() APIs to register/unregister one hwlock controller
hwspinlock: Add devm_xxx() APIs to request/free hwlock
hwspinlock: Add one new API to support getting a specific hwlock by the name
On systems where some controllers get a dynamic ID assigned and some have
a fixed number (e.g. from ACPI tables), the current implementation might
run into an IDR collision: in case of a fixed bus number is gotten by a
driver (but not marked busy in IDR tree) and a driver with dynamic bus
number gets the same ID and predictably fails.
Fix this by means of checking-in fixed IDsin IDR as far as dynamic ones
at the moment of the controller registration.
Fixes: 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
Signed-off-by: Kirill Kapranov <kirill.kapranov@compulab.co.il>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
When porting (Q)SPI controller drivers from the MTD layer to the SPI
layer, the naming scheme for the memory devices changes. To be able
to keep compatibility with the old drivers naming scheme, a name
field is added to struct spi_mem and a hook is added to let controller
drivers set a custom name for the memory device.
Example for the FSL QSPI driver:
Name with the old driver: 21e0000.qspi,
or with multiple devices: 21e0000.qspi-0, 21e0000.qspi-1, ...
Name with the new driver without spi_mem_get_name: spi4.0
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit removed include headers of linux/of.h and linux/of_platform.h,
because they are not used.
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add SPI_3WIRE support to spi-gpio controller introducing
set_line_direction function pointer in spi_bitbang data structure.
Spi-gpio controller has been tested using hts221 temp/rh iio sensor
running in 3wire mode and lsm6dsm running in 4wire mode
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add the capability to specify the flag parameter used in
bitbang_txrx_be_cpha{0,1} through the txrx_word function pointers of
spi_bitbang data structure. That feature will be used to add spi-3wire
support to the spi-gpio controller
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add SPI controller driver implemented in Socionext UniPhier SoCs.
UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.
This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.
This commit is implemented in PIO transfer mode, not DMA transfer.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Even if the chip select line is not controlled by the SPFI
hardware, the device select bits need to be set to specify
the chip select line in use for the hardware to know what
parameters to use for the current transfer.
Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Variable count, l, mcspi and spi_cntrl are being assigned but are
never used hence they are redundant and can be removed.
Cleans up clang warnings:
warning: variable 'count' set but not used [-Wunused-but-set-variable]
warning: variable 'l' set but not used [-Wunused-but-set-variable]
warning: variable 'mcspi' set but not used [-Wunused-but-set-variable]
warning: variable 'spi_cntrl' set but not used [-Wunused-but-set-variable]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Because the SPI controller deasserts the chip select when the TX fifo is
empty (which may happen in the middle of a transfer), the CS should be
handled by linux. Unfortunately, some or all of the first four chip
selects are not muxable as GPIOs, depending on the SoC.
There is a way to bitbang those pins by using the SPI boot controller so
use it to set the chip selects.
At init time, it is also necessary to give control of the SPI interface to
the Designware IP.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Dynamic burst mode allows to group together multiple words and send them
in one continuous burst. When the number of bytes to be sent is not a
strict multiple of the FIFO entry size (32 bits), the controller expects
the non aligned bits to be sent first.
This commit adds support for this particular constraint, avoiding the
need to send the non-aligned bytes one by one at the end of the
transfer, speeding-up transfer speed in that case.
With this method, a transfer is divided into multiple bursts, limited in
size by the maximum amount of data that the controller can transfer in
one continuous burst (which is 512 bytes).
The non-512 byte part of the transfer is sent first. The remaining bytes
to be transferred in the current burst is stored in the 'remainder'
field.
With this method, the read_u32 field is no longer necessary, and is
removed.
This was tested on imx6 solo and imx6 quad.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi_imx_can_dma function computes the watermark level so that
the transfer will fit in exactly N bursts (without a remainder).
The smallest watermark level possible being one FIFO entry per burst, we
can't never have a case where the transfer size isn't divsiible by 1.
Remove the extra check for the wml being different than 0.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPI core enforces that we always use the next power-of-two number of
bytes to store words. As a result, a 24 bits word will be stored in 4
bytes.
This commit fixes the spi_imx_bytes_per_word function to return the
correct number of bytes.
This also allows to get rid of unnecessary checks in the can_dma
function, since the SPI core validates that we always have a transfer
length that is a multiple of the number of bytes per word.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dynamic bursts mode allows to group together multiple words into a
single burst. To do so, it's necessary that words can be packed into the
32-bits FIFO entries, so we can't allow using this mode with bit_per_words
different to 8, 16 or 32.
This prevents shitfing out extra clock ticks for transfers with
bit_per_word values not aligned on 8 bits.
With that , we are sure that only the correct number of bits is
shifted out at each transfer, so we don't need to mask out the remaining
parts of the words.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some fields in struct spi_imx_data are assigned a different value twice
in a row, in spi_imx_setupxfer.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Allow platform specific drivers to provide their own set_cs callback when
the IP integration requires it.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
