The driver core ignores the return value of struct device_driver::remove
(because in general there is nothing that can be done about that). So
add a warning when an spi driver returns an error.
This simplifies the quest to make struct device_driver::remove return void.
A consequent change would be to make struct spi_driver::remove return void,
but I'm keeping this quest for later (or someone else).
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119161604.2633521-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The eventual goal is to get rid of the callbacks in struct
device_driver. Other than not using driver callbacks there should be no
side effect of this patch.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119161604.2633521-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Consider an spi driver with a .probe but without a .remove callback (e.g.
rtc-ds1347). The function spi_drv_probe() is called to bind a device and
so dev_pm_domain_attach() is called. As there is no remove callback
spi_drv_remove() isn't called at unbind time however and so calling
dev_pm_domain_detach() is missed and the pm domain keeps active.
To fix this always use both spi_drv_probe() and spi_drv_remove() and
make them handle the respective callback not being set. This has the
side effect that for a (hypothetical) driver that has neither .probe nor
remove the clk and pm domain setup is done.
Fixes: 33cf00e570 ("spi: attach/detach SPI device to the ACPI power domain")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119161604.2633521-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in mxs_spi_probe, so we should fix it.
Fixes: b7969caf41 ("spi: mxs: implement runtime pm")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201106012421.95420-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Since 5.10-rc1 i.MX is a devicetree-only platform and the existing
.id_table support in this driver was only useful for old non-devicetree
platforms.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20201116202606.29888-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If the calls to of_match_device(), of_alias_get_id(),
devm_ioremap_resource(), devm_regmap_init_mmio() or devm_clk_get()
fail on probe of the NPCM FIU SPI driver, the spi_controller struct is
erroneously not freed.
Fix by switching over to the new devm_spi_alloc_master() helper.
Fixes: ace55c411b ("spi: npcm-fiu: add NPCM FIU controller driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.4+: 5e844cc37a: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/a420c23a363a3bc9aa684c6e790c32a8af106d17.1605512876.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
It turns out the IRQs most like can be unmasked before the controller is
enabled with no problematic consequences. The manual doesn't explicitly
state that, but the examples perform the controller initialization
procedure in that order. So the commit da8f58909e ("spi: dw: Unmask IRQs
after enabling the chip") hasn't been that required as I thought. But
anyway setting the IRQs up after the chip enabling still worth adding
since it has simplified the code a bit. The problem is that it has
introduced a potential bug. The transfer handler pointer is now
initialized after the IRQs are enabled. That may and eventually will cause
an invalid or uninitialized callback invocation. Fix that just by
performing the callback initialization before the IRQ unmask procedure.
Fixes: da8f58909e ("spi: dw: Unmask IRQs after enabling the chip")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201117094054.4696-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
MT8192 spi-nor is an independent sub system, we need extra control axi
bus clock for it. Add support for the additional axi clock to allow it
to be configured appropriately.
Signed-off-by: bayi cheng <bayi.cheng@mediatek.com>
Tested-by: Ikjoon Jang <ikjn@chromium.org>
Link: https://lore.kernel.org/r/1605084902-13151-2-git-send-email-bayi.cheng@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix to return the error code from
devm_reset_control_get_optional_exclusive() instaed of 0
in cqspi_probe().
Fixes: 31fb632b5d ("spi: Move cadence-quadspi driver to drivers/spi/")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20201116141836.2970579-1-chengzhihao1@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Clang warns:
drivers/spi/spi-bcm2835aux.c:532:50: warning: variable 'err' is
uninitialized when used here [-Wuninitialized]
dev_err(&pdev->dev, "could not get clk: %d\n", err);
^~~
./include/linux/dev_printk.h:112:32: note: expanded from macro 'dev_err'
_dev_err(dev, dev_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~
drivers/spi/spi-bcm2835aux.c:495:9: note: initialize the variable 'err'
to silence this warning
int err;
^
= 0
1 warning generated.
Restore the assignment so that the error value can be used in the
dev_err statement and there is no uninitialized memory being leaked.
Fixes: e13ee6cc47 ("spi: bcm2835aux: Fix use-after-free on unbind")
Link: https://github.com/ClangBuiltLinux/linux/issues/1199
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lore.kernel.org/r/20201113180701.455541-1-natechancellor@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Here's my proposal to fix the use-after-free bugs reported by
Sascha Hauer and Florian Fainelli:
I scrutinized all SPI drivers in the v5.10 tree:
* There are 9 drivers with a use-after-free in the ->remove() hook
caused by accessing driver private data after spi_unregister_controller().
* There are 8 drivers which leak the spi_controller in the ->probe()
error path because of a missing spi_controller_put().
I'm introducing devm_spi_alloc_master/slave() which automatically
calls spi_controller_put() on ->remove(). This fixes both classes
of bugs while at the same time reducing code amount and complexity
in the ->probe() hook.
I propose that spi_controller_unregister() should no longer release
a reference on the spi_controller. Instead, drivers need to either
do it themselves or use one of the devm functions introduced herein.
The vast majority of drivers can be converted to the devm functions.
See the commit message of patch [1/4] for the rationale and details.
Enclosed are patches for 3 Broadcom drivers.
Patches for the other drivers are on this branch:
https://github.com/l1k/linux/commits/spi_fixes
@Florian Fainelli: Could you verify that there are no KASAN splats or
leaks with these patches? Unfortunately I do not have any SPI-capable
hardware at my disposal right now, so can only compile-test. You may
want to augment spi_controller_release() with a printk() to log when
the spi_controller is freed.
@Mark Brown: Patches [2/4] to [4/4] reference the SHA-1 of patch [1/4]
in their stable tags. Because the hash is unknown to me until you apply
the patch, I've used "123456789abc" as a placeholder. You'll have to
replace the hash if/when applying. Alternatively, only apply patch [1/4]
and I'll repost the other patches with the hash fixed up.
Thanks!
Lukas Wunner (4):
spi: Introduce device-managed SPI controller allocation
spi: bcm2835: Fix use-after-free on unbind
spi: bcm2835aux: Fix use-after-free on unbind
spi: bcm-qspi: Fix use-after-free on unbind
drivers/spi/spi-bcm-qspi.c | 34 ++++++++-------------
drivers/spi/spi-bcm2835.c | 24 +++++----------
drivers/spi/spi-bcm2835aux.c | 21 +++++--------
drivers/spi/spi.c | 58 +++++++++++++++++++++++++++++++++++-
include/linux/spi/spi.h | 19 ++++++++++++
5 files changed, 103 insertions(+), 53 deletions(-)
--
2.28.0
Normally the last reference on an spi_controller is released by
spi_unregister_controller(). In the case of the i.MX lpspi driver,
the spi_controller is registered with devm_spi_register_controller(),
so spi_unregister_controller() is invoked automatically after the driver
has unbound.
However the driver already releases the last reference in
fsl_lpspi_remove() through a gratuitous call to spi_master_put(),
causing a use-after-free when spi_unregister_controller() is
subsequently invoked by the devres framework.
Fix by dropping the superfluous spi_master_put().
Fixes: 944c01a889 ("spi: lpspi: enable runtime pm for lpspi")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.2+
Cc: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/ab3c0b18bd820501a12c85e440006e09ec0e275f.1604874488.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
If the calls to devm_platform_ioremap_resource(), irq_of_parse_and_map()
or devm_request_irq() fail on probe of the ST SSC4 SPI driver, the
runtime PM disable depth is incremented even though it was not
decremented before. Fix it.
Fixes: cd050abeba ("spi: st-ssc4: add missed pm_runtime_disable")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.5+
Cc: Chuhong Yuan <hslester96@gmail.com>
Link: https://lore.kernel.org/r/fbe8768c30dc829e2d77eabe7be062ca22f84024.1604874488.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
If the calls to devm_request_irq() or devm_spi_register_master() fail
on probe of the PIC32 SPI driver, the DMA channels requested by
pic32_spi_dma_prep() are erroneously not released. Plug the leak.
Fixes: 1bcb9f8ceb ("spi: spi-pic32: Add PIC32 SPI master driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v4.7+
Cc: Purna Chandra Mandal <purna.mandal@microchip.com>
Link: https://lore.kernel.org/r/9624250e3a7aa61274b38219a62375bac1def637.1604874488.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
If the calls to platform_get_irq() or devm_request_irq() fail on probe
of the SynQuacer SPI driver, the clock "sspi->clk" is erroneously not
unprepared and disabled.
If the clock rate "master->max_speed_hz" cannot be determined, the same
happens and in addition the spi_master struct is not freed.
Fix it.
Fixes: b0823ee35c ("spi: Add spi driver for Socionext SynQuacer platform")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.3+
Cc: Masahisa Kojima <masahisa.kojima@linaro.org>
Link: https://lore.kernel.org/r/232281df1ab91d8f0f553a62d5f97fc264ace4da.1604874488.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
bcm_qspi_remove() calls spi_unregister_master() even though
bcm_qspi_probe() calls devm_spi_register_master(). The spi_master is
therefore unregistered and freed twice on unbind.
Moreover, since commit 0392727c26 ("spi: bcm-qspi: Handle clock probe
deferral"), bcm_qspi_probe() leaks the spi_master allocation if the call
to devm_clk_get_optional() fails.
Fix by switching over to the new devm_spi_alloc_master() helper which
keeps the private data accessible until the driver has unbound and also
avoids the spi_master leak on probe.
While at it, fix an ordering issue in bcm_qspi_remove() wherein
spi_unregister_master() is called after uninitializing the hardware,
disabling the clock and freeing an IRQ data structure. The correct
order is to call spi_unregister_master() *before* those teardown steps
because bus accesses may still be ongoing until that function returns.
Fixes: fa236a7ef2 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v4.9+: 123456789abc: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v4.9+
Cc: Kamal Dasu <kdasu.kdev@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/5e31a9a59fd1c0d0b795b2fe219f25e5ee855f9d.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
bcm2835aux_spi_remove() accesses the driver's private data after calling
spi_unregister_master() even though that function releases the last
reference on the spi_master and thereby frees the private data.
Fix by switching over to the new devm_spi_alloc_master() helper which
keeps the private data accessible until the driver has unbound.
Fixes: b9dd3f6d41 ("spi: bcm2835aux: Fix controller unregister order")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v4.4+: 123456789abc: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v4.4+: b9dd3f6d41: spi: bcm2835aux: Fix controller unregister order
Cc: <stable@vger.kernel.org> # v4.4+
Link: https://lore.kernel.org/r/b290b06357d0c0bdee9cecc539b840a90630f101.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
bcm2835_spi_remove() accesses the driver's private data after calling
spi_unregister_controller() even though that function releases the last
reference on the spi_controller and thereby frees the private data.
Fix by switching over to the new devm_spi_alloc_master() helper which
keeps the private data accessible until the driver has unbound.
Fixes: f8043872e7 ("spi: add driver for BCM2835")
Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Reported-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v3.10+: 123456789abc: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v3.10+
Cc: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/ad66e0a0ad96feb848814842ecf5b6a4539ef35c.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI driver probing currently comprises two steps, whereas removal
comprises only one step:
spi_alloc_master()
spi_register_controller()
spi_unregister_controller()
That's because spi_unregister_controller() calls device_unregister()
instead of device_del(), thereby releasing the reference on the
spi_controller which was obtained by spi_alloc_master().
An SPI driver's private data is contained in the same memory allocation
as the spi_controller struct. Thus, once spi_unregister_controller()
has been called, the private data is inaccessible. But some drivers
need to access it after spi_unregister_controller() to perform further
teardown steps.
Introduce devm_spi_alloc_master() and devm_spi_alloc_slave(), which
release a reference on the spi_controller struct only after the driver
has unbound, thereby keeping the memory allocation accessible. Change
spi_unregister_controller() to not release a reference if the
spi_controller was allocated by one of these new devm functions.
The present commit is small enough to be backportable to stable.
It allows fixing drivers which use the private data in their ->remove()
hook after it's been freed. It also allows fixing drivers which neglect
to release a reference on the spi_controller in the probe error path.
Long-term, most SPI drivers shall be moved over to the devm functions
introduced herein. The few that can't shall be changed in a treewide
commit to explicitly release the last reference on the controller.
That commit shall amend spi_unregister_controller() to no longer release
a reference, thereby completing the migration.
As a result, the behaviour will be less surprising and more consistent
with subsystems such as IIO, which also includes the private data in the
allocation of the generic iio_dev struct, but calls device_del() in
iio_device_unregister().
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in sprd_spi_remove, so we should fix it.
Fixes: e7d973a31c ("spi: sprd: Add SPI driver for Spreadtrum SC9860")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Acked-by: Chunyan Zhang <zhang.lyra@gmail.com>
Link: https://lore.kernel.org/r/20201106015035.139574-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In the case that the SPI mux isn't set, the transfer_one_message
function returns without finalizing the message. This means that
the transfer never completes, resulting in hung tasks and an
eventual kernel panic. Fix it by finalizing the transfer in this
case.
Fixes: 9211a441e6 ("spi: fsi: Check mux status before transfers")
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20201110214736.25718-1-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit f3186dd876 ("spi: Optionally use GPIO descriptors for CS GPIOs")
introduced the optional use of GPIO descriptors for chip selects.
A side-effect of this change: when a SPI bus uses GPIO descriptors,
all its client devices have SPI_CS_HIGH set in spi->mode. This flag is
required for the SPI bus to operate correctly.
This unfortunately breaks many client drivers, which use the following
pattern to configure their underlying SPI bus:
static int client_device_probe(struct spi_device *spi)
{
...
spi->mode = SPI_MODE_0;
spi->bits_per_word = 8;
err = spi_setup(spi);
..
}
In short, many client drivers overwrite the SPI_CS_HIGH bit in
spi->mode, and break the underlying SPI bus driver.
This is especially true for Freescale/NXP imx ecspi, where large
numbers of spi client drivers now no longer work.
Proposed fix:
-------------
When using gpio descriptors, depend on gpiolib to handle CS polarity.
Existing quirks in gpiolib ensure that this is handled correctly.
Existing gpiolib behaviour will force the polarity of any chip-select
gpiod to active-high (if 'spi-active-high' devicetree prop present) or
active-low (if 'spi-active-high' absent). Irrespective of whether
the gpio is marked GPIO_ACTIVE_[HIGH|LOW] in the devicetree.
Loose ends:
-----------
If this fix is applied:
- is commit 138c9c32f0
("spi: spidev: Fix CS polarity if GPIO descriptors are used")
still necessary / correct ?
Fixes: f3186dd876 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20201106150706.29089-1-TheSven73@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in callers(spi_imx_prepare_message and
spi_imx_remove), so we should fix it.
Fixes: 525c9e5a32 ("spi: imx: enable runtime pm support")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201102145835.4765-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If the call to of_device_get_match_data() fails on probe of the Atmel
QuadSPI driver, the clock "aq->pclk" is erroneously not unprepared and
disabled. Fix it.
Fixes: 2e5c888873 ("spi: atmel-quadspi: add support for sam9x60 qspi controller")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.1+
Cc: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/8f8dc2815aa97b2378528f08f923bf81e19611f0.1604874488.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix the missing clk_disable_unprepare() before return
from bcm63xx_hsspi_resume in the error handling case when
fails to prepare and enable bs->pll_clk.
Fixes: 0fd85869c2 ("spi/bcm63xx-hsspi: keep pll clk enabled")
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/20201103074911.195530-1-miaoqinglang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in two callers(tegra_spi_setup and
tegra_spi_resume), so we should fix it.
Fixes: f333a331ad ("spi/tegra114: add spi driver")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201103141306.5607-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in tegra_sflash_resume, so we should fix it.
Fixes: 8528547bcc ("spi: tegra: add spi driver for sflash controller")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201103141323.5841-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in two callers(tegra_slink_setup and
tegra_slink_resume), so we should fix it.
Fixes: dc4dc36056 ("spi: tegra: add spi driver for SLINK controller")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201103141345.6188-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix the missing clk_disable_unprepare() before return
from mt7621_spi_probe in the error handling case.
Fixes: cbd66c626e ("spi: mt7621: Move SPI driver out of staging")
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/20201103074912.195576-1-miaoqinglang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in ti_qspi_setup, so we should fix it.
Fixes: 505a14954e ("spi/qspi: Add qspi flash controller")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201103140947.3815-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in two callers(stm32_qspi_exec_op and
stm32_qspi_setup), so we should fix it.
Fixes: 9d282c17b0 ("spi: stm32-qspi: Add pm_runtime support")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Link: https://lore.kernel.org/r/20201106015357.141235-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Removing the duplicate gpio chip select level handling in
bcm2835_spi_setup() left the lflags variable uninitialized. Avoid trhe
use of such variable by passing default flags to
gpiochip_request_own_desc().
Fixes: 5e31ba0c05 ("spi: bcm2835: fix gpio cs level inversion")
Signed-off-by: Martin Hundebøll <martin@geanix.com>
Link: https://lore.kernel.org/r/20201105090615.620315-1-martin@geanix.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in stm32_spi_resume, so we should fix it.
Fixes: db96bf976a ("spi: stm32: fixes suspend/resume management")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Reviewed-by: Alain Volmat <alain.volmat@st.com>
Link: https://lore.kernel.org/r/20201106015217.140476-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in spi_mem_access_start, so we should fix it.
Fixes: f86c24f479 ("spi: spi-mem: Split spi_mem_exec_op() code")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201103140910.3482-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit 530b5affc6 ("spi: fsl-dspi: fix use-after-free in
remove path"), this driver causes a "NULL pointer dereference"
in dspi_suspend/resume.
This is because since this commit, the drivers private data point to
"dspi" instead of "ctlr", the codes in suspend and resume func were
not modified correspondly.
Fixes: 530b5affc6 ("spi: fsl-dspi: fix use-after-free in remove path")
Signed-off-by: Zhao Qiang <qiang.zhao@nxp.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20201103020546.1822-1-qiang.zhao@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix smatch warning:
drivers/spi/spi-mem.c:746 spi_mem_probe() warn: passing zero to 'PTR_ERR'
Fixes: 5d27a9c8ea ("spi: spi-mem: Extend the SPI mem interface to set a custom memory name")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20201031033042.42892-1-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak in img_spfi_resume, so we should fix it.
Fixes: deba25800a ("spi: Add driver for IMG SPFI controller")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201102145651.3875-1-zhangqilong3@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The IP's DMA capabilities are described in the SoC dtsi, to spare
users duplicating the DMA bindings in their board device tree. Users
that don't want to use DMA, have to overwrite the DMA bindings in
their board device tree. An example is:
commit ddcdaeb882 ("ARM: dts: at91: sama5d2: Add DMA bindings for the SPI and UART flx4 functions")
When the DMA bindings are overwritten, one could see on the console:
atmel_spi fc018400.spi: error -ENODEV: No TX DMA channel, DMA is disabled
atmel_spi fc018400.spi: Atmel SPI Controller using PIO only
Choosing to not use DMA is not a reason to print an error message.
More, the user is already informed when PIO is used: "Atmel SPI Controller
using PIO only". Downgrade to dev_dbg when dma_request_chan() fails.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201030121116.869105-1-tudor.ambarus@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The work on improving gpio chip-select in spi core, and the following
fixes, has caused the bcm2835 spi driver to use wrong levels. Fix this
by simply removing level handling in the bcm2835 driver, and let the
core do its work.
Fixes: 3e5ec1db8b ("spi: Fix SPI_CS_HIGH setting when using native and GPIO CS")
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin Hundebøll <martin@geanix.com>
Link: https://lore.kernel.org/r/20201014090230.2706810-1-martin@geanix.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If SPI is used for periodic polling any sensor, significant delays
sometimes appear. Switching on module clocks during resume lead to delays.
Enabling autosuspend mode causes the controller to not suspend between
SPI transfers and the delays disappear.
The commit also remove unnecessary call to pm_runtime_idle() used
to explicit put device to suspended state. Without pm_runtime_idle() PM
core will put device in the suspended state just after probe() returns.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20201019150343.2520-1-akochetkov@lintech.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
If SPI is used for periodic polling any sensor, significant delays
sometimes appear. Switching on module clocks during resume lead to delays.
Enabling autosuspend mode causes the controller to not suspend between
SPI transfers and the delays disappear.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Link: https://lore.kernel.org/r/20201016085014.31667-1-al.kochet@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
DMA-based transfer will be enabled if data length is larger than FIFO size
(64 bytes for A64). This greatly reduce number of interrupts for
transferring data.
For smaller data size PIO mode will be used. In PIO mode whole buffer will
be loaded into FIFO.
If driver failed to request DMA channels then it fallback for PIO mode.
Tested on SOPINE (https://www.pine64.org/sopine/)
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20201022075221.23332-1-akochetkov@lintech.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
SoC changes, a substantial part of this is cleanup of some of the older
platforms that used to have a bunch of board files. In particular:
- Removal of non-DT i.MX platforms that haven't seen activity in years,
it's time to remove them.
- A bunch of cleanup and removal of platform data for TI/OMAP platforms,
moving over to genpd for power/reset control (yay!)
- Major cleanup of Samsung S3C24xx and S3C64xx platforms, moving them
closer to multiplatform support (not quite there yet, but getting
close).
THere are a few other changes too, smaller fixlets, etc. For new
platform support, the primary ones re:
- New SoC: Hisilicon SD5203, ARM926EJ-S platform.
- Cpufreq support for i.MX7ULP
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Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC platform updates from Olof Johansson:
"SoC changes, a substantial part of this is cleanup of some of the
older platforms that used to have a bunch of board files.
In particular:
- Remove non-DT i.MX platforms that haven't seen activity in years,
it's time to remove them.
- A bunch of cleanup and removal of platform data for TI/OMAP
platforms, moving over to genpd for power/reset control (yay!)
- Major cleanup of Samsung S3C24xx and S3C64xx platforms, moving them
closer to multiplatform support (not quite there yet, but getting
close).
There are a few other changes too, smaller fixlets, etc. For new
platform support, the primary ones are:
- New SoC: Hisilicon SD5203, ARM926EJ-S platform.
- Cpufreq support for i.MX7ULP"
* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (121 commits)
ARM: mstar: Select MStar intc
ARM: stm32: Replace HTTP links with HTTPS ones
ARM: debug: add UART early console support for SD5203
ARM: hisi: add support for SD5203 SoC
ARM: omap3: enable off mode automatically
clk: imx: imx35: Remove mx35_clocks_init()
clk: imx: imx31: Remove mx31_clocks_init()
clk: imx: imx27: Remove mx27_clocks_init()
ARM: imx: Remove unused definitions
ARM: imx35: Retrieve the IIM base address from devicetree
ARM: imx3: Retrieve the AVIC base address from devicetree
ARM: imx3: Retrieve the CCM base address from devicetree
ARM: imx31: Retrieve the IIM base address from devicetree
ARM: imx27: Retrieve the CCM base address from devicetree
ARM: imx27: Retrieve the SYSCTRL base address from devicetree
ARM: s3c64xx: bring back notes from removed debug-macro.S
ARM: s3c24xx: fix Wunused-variable warning on !MMU
ARM: samsung: fix PM debug build with DEBUG_LL but !MMU
MAINTAINERS: mark linux-samsung-soc list non-moderated
ARM: imx: Remove remnant board file support pieces
...
525c9e5a32 introduced pm_runtime support for the i.MX SPI driver. With
this pm_runtime is used to bring up the clocks initially. When CONFIG_PM
is disabled the clocks are no longer enabled and the driver doesn't work
anymore. Fix this by enabling the clocks in the probe function and
telling pm_runtime that the device is active using
pm_runtime_set_active().
Fixes: 525c9e5a32 spi: imx: enable runtime pm support
Tested-by: Christian Eggers <ceggers@arri.de> [tested for !CONFIG_PM only]
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20201021104513.21560-1-s.hauer@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The amount of changes is smaller at this round (what a surprise),
but lots of activity is seen. Most of changes are about ASoC
driver development, especially Intel platforms.
Here are some highlights:
General:
* Replace all tasklet usages with other alternatives
* Cleanup of the ASoC error unwinding code
* Fixes for trivial issues caught by static checker
* Spell fixes allover the places
ALSA Core:
* Lockdep fix for control devices
* Fix for potential OSS sequencer mutex stalls
HD-audio and USB-audio:
* SoundBlaster AE-7 support
* Changes in quirk table for the rename handling
* Quirks for HP and ASUS machines, Pioneer DJ DJM-250MK2.
ASoC:
* Lots of updates for Intel SOF and SoundWire enablement
* Replacement of the DSP driver for some older x86 systems;
the new code was written from scratch, better maintenance
expected
* Helpers for parsing auxiluary devices from the device tree
* New support for AllWinner A64, Cirrus Logic CS4234, Mediatek
MT6359 Microchip S/PDIF TX and RX controllers, Realtek RT1015P,
and Texas Instruments J721E, TAS2110, TAS2564 and TAS2764
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Merge tag 'sound-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound updates from Takashi Iwai:
"The amount of changes is smaller at this round (what a surprise), but
lots of activity is seen. Most of changes are about ASoC driver
development, especially Intel platforms. Here are some highlights:
General:
- Replace all tasklet usages with other alternatives
- Cleanup of the ASoC error unwinding code
- Fixes for trivial issues caught by static checker
- Spell fixes allover the places
ALSA Core:
- Lockdep fix for control devices
- Fix for potential OSS sequencer mutex stalls
HD-audio and USB-audio:
- SoundBlaster AE-7 support
- Changes in quirk table for the rename handling
- Quirks for HP and ASUS machines, Pioneer DJ DJM-250MK2.
ASoC:
- Lots of updates for Intel SOF and SoundWire enablement
- Replacement of the DSP driver for some older x86 systems; the new
code was written from scratch, better maintenance expected
- Helpers for parsing auxiluary devices from the device tree
- New support for AllWinner A64, Cirrus Logic CS4234, Mediatek MT6359
Microchip S/PDIF TX and RX controllers, Realtek RT1015P, and Texas
Instruments J721E, TAS2110, TAS2564 and TAS2764"
* tag 'sound-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (498 commits)
ALSA: hda/hdmi: fix incorrect locking in hdmi_pcm_close
ALSA: hda: fix jack detection with Realtek codecs when in D3
ALSA: fireworks: use semicolons rather than commas to separate statements
ALSA: hda: use semicolons rather than commas to separate statements
ALSA: hda/i915 - fix list corruption with concurrent probes
ASoC: dmaengine: Document support for TX only or RX only streams
ASoC: mchp-spdiftx: remove 'TX' from playback stream name
ASoC: ti: davinci-mcasp: Use &pdev->dev for early dev_warn
ASoC: tas2764: Add the driver for the TAS2764
dt-bindings: tas2764: Add the TAS2764 binding doc
ASoC: Intel: catpt: Add explicit DMADEVICES kconfig dependency
ASoC: Intel: catpt: Fix compilation when CONFIG_MODULES is disabled
ASoC: stm32: dfsdm: add actual resolution trace
ASoC: stm32: dfsdm: change rate limits
ASoC: qcom: sc7180: Add support for audio over DP
Asoc: qcom: lpass-platform : Increase buffer size
ASoC: qcom: Add support for lpass hdmi driver
Asoc: qcom: lpass:Update lpaif_dmactl members order
Asoc:qcom:lpass-cpu:Update dts property read API
ASoC: dt-bindings: Add dt binding for lpass hdmi
...
Baikal-T1 is equipped with three DW APB SSI-based MMIO SPI controllers.
Two of them are pretty much normal: with IRQ, DMA, FIFOs of 64 words
depth, 4x CSs, but the third one as being a part of the Baikal-T1 System
Boot Controller has got a very limited resources: no IRQ, no DMA, only a
single native chip-select and Tx/Rx FIFO with just 8 words depth
available. In order to provide a transparent initial boot code execution
the Boot SPI controller is also utilized by an vendor-specific IP-block,
which exposes an SPI flash direct mapping interface. Since both direct
mapping and SPI controller normal utilization are mutual exclusive only
one of these interfaces can be used to access an external SPI slave
device. That's why a dedicated mux is embedded into the System Boot
Controller. All of that is taken into account in the Baikal-T1-specific DW
APB SSI glue driver implemented by means of the DW SPI core module.
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-22-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
A functionality of the poll-based transfer has been removed by
commit 1ceb09717e98 ("spi: dw: remove cs_control and poll_mode members
from chip_data") with a justification that "there is no user of one
anymore". It turns out one of our DW APB SSI core is synthesized with no
IRQ line attached and the only possible way of using it is to implement a
poll-based SPI transfer procedure. So we have to get the removed
functionality back, but with some alterations described below.
First of all the poll-based transfer is activated only if the DW SPI
controller doesn't have an IRQ line attached and the Linux IRQ number is
initialized with the IRQ_NOTCONNECTED value. Secondly the transfer
procedure is now executed with a delay performed between writer and reader
methods. The delay value is calculated based on the number of data words
expected to be received on the current iteration. Finally the errors
status is checked on each iteration.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-20-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
In some circumstances the current implementation of the SPI memory
operations may occasionally fail even though they are executed in the
atomic context. This may happen if the system bus is relatively slow in
comparison to the SPI bus frequency, or there is a concurrent access to
it, which makes the MMIO-operations occasionally stalling before
push-pulling data from the DW APB SPI FIFOs. These two problems we've
discovered on the Baikal-T1 SoC. In order to fix them we have no choice
but to set an artificial limitation on the SPI bus speed.
Note currently this limitation will be only applicable for the memory
operations, since the standard SPI core interface is implemented with an
assumption that there is no problem with the automatic CS toggling.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-19-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Aside from the synchronous Tx-Rx mode, which has been utilized to create
the normal SPI transfers in the framework of the DW SSI driver, DW SPI
controller supports Tx-only and EEPROM-read modes. The former one just
enables the controller to transmit all the data from the Tx FIFO ignoring
anything retrieved from the MISO lane. The later mode is so called
write-then-read operation: DW SPI controller first pushes out all the data
from the Tx FIFO, after that it'll automatically receive as much data as
has been specified by means of the CTRLR1 register. Both of those modes
can be used to implement the memory operations supported by the SPI-memory
subsystem.
The memory operation implementation is pretty much straightforward, except
a few peculiarities we have had to take into account to make things
working. Since DW SPI controller doesn't provide a way to directly set and
clear the native CS lane level, but instead automatically de-asserts it
when a transfer going on, we have to make sure the Tx FIFO isn't empty
during entire Tx procedure. In addition we also need to read data from the
Rx FIFO as fast as possible to prevent it' overflow with automatically
fetched incoming traffic. The denoted peculiarities get to cause even more
problems if DW SSI controller is equipped with relatively small FIFO and
is connected to a relatively slow system bus (APB) (with respect to the
SPI bus speed). In order to workaround the problems for as much as it's
possible, the memory operation execution procedure collects all the Tx
data into a single buffer and disables the local IRQs to speed the
write-then-optionally-read method up.
Note the provided memory operations are utilized by default only if
a glue driver hasn't provided a custom version of ones and this is not
a DW APB SSI controller with fixed automatic CS toggle functionality.
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-18-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
The DW SSI errors handling method can be generically implemented for all
types of the transfers: IRQ, DMA and poll-based ones. It will be a
function which checks the overflow/underflow error flags and resets the
controller if any of them is set. In the framework of this commit we make
use of the new method to detect the errors in the IRQ- and DMA-based SPI
transfer execution procedures.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-17-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
The parameter will be needed for another wait-done method being added in
the framework of the SPI memory operation modification in a further
commit.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-16-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
By design of the currently available native set_cs callback, the CS
de-assertion will be done only if it's required by the corresponding
controller capability. But in order to pre-fill the Tx FIFO buffer with
data during the SPI memory ops execution the SER register needs to be left
cleared before that. We'll also need a way to explicitly set and clear the
corresponding CS bit at a certain moment of the operation. Let's alter
the set_cs function then to also de-activate the CS, when it's required.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-15-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI memory operations implementation will require to have the CS register
cleared before executing the operation in order not to have the
transmission automatically started prior the Tx FIFO is pre-initialized.
Let's clear the register then on explicit controller reset to fulfil the
requirements in case of an error or having the CS left set by a bootloader
or another software.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-14-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
It's pointless to enable the chip back if the DMA setup procedure fails,
since we'll disable it on the next transfer anyway. For the same reason We
don't do that in case of a failure detected in any other methods called
from the transfer_one() method.
While at it consider any non-zero value returned from the dma_setup
callback to be erroneous as it's supposed to be in the kernel.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-13-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
It's theoretically erroneous to enable IRQ before the chip is turned on.
If IRQ handler gets executed before the chip is enabled, then any data
written to the Tx FIFO will be just ignored.
I say "theoretically" because we haven't noticed any problem with that,
but let's fix it anyway just in case...
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-12-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
In order to make the transfer_one() callback method more readable and
for unification with the DMA-based transfer, let's detach the IRQ setup
procedure into a dedicated function. While at it rename the IRQ-based
transfer handler function to be dw_spi-prefixe and looking more like the
DMA-related one.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-11-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Current IRQ-based SPI transfer execution procedure doesn't work well at
the final stage of the execution. If all the Tx data is sent out (written
to the Tx FIFO) but there is some data left to receive, the Tx FIFO Empty
IRQ will constantly happen until all of the requested inbound data is
received. Though for a short period of time, but it will make the system
less responsive. In order to fix that let's refactor the SPI transfer
execution procedure by taking the Rx FIFO Full IRQ into account. We'll read
and write SPI transfer data each time the IRQ happens as before. If all
the outbound data is sent out, we'll disable the Tx FIFO Empty IRQ. If
there is still some data to receive, we'll adjust the Rx FIFO Threshold
level, so the next IRQ would be raised at the moment of all incoming data
being available in the Rx FIFO.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-10-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
The Tx and Rx data write/read procedure can be significantly simplified by
using Tx/Rx transfer lengths instead of the end pointers. By having the
Tx/Rx data leftover lengths (in the number of transfer words) we can get
rid of all subtraction and division operations utilized here and there in
the tx_max(), rx_max(), dw_writer() and dw_reader() methods. Such
modification will not only give us the more optimized IO procedures, but
will make the data IO methods much more readable than before.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-9-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
DW APB SSI controller can be used by the two SPI core interfaces:
traditional SPI transfers and SPI memory operations. The controller needs
to be accordingly configured at runtime when the corresponding operations
are executed. In order to do that for the both interfaces from a single
function we introduce a new data wrapper for the transfer mode, data
width, number of data frames (for the automatic data transfer) and the bus
frequency. It will be used by the update_config() method to tune the DW
APB SSI up.
The update_config() method is made exported to be used not only by the DW
SPI core driver, but by the glue layer drivers too. This will be required
in a coming further commit.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-8-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Rx sample delay can be SPI device specific, and should be synchronously
initialized with the rest of the communication and peripheral device
related controller setups. So let's move the Rx-sample delay setup into
the DW APB SSI configuration update method.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-7-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
The code currently responsible for the SPI communication speed setting up
is a bit messy. Most likely for some historical reason the bus frequency
is saved in the peripheral chip private data. It's pointless now since the
custom communication speed is a SPI-transfer-specific thing and only if
there is no SPI transfer data specified (like during the SPI memory
operations) it can be taken from the SPI device structure. But even in the
later case there is no point in having the clock divider and the SPI bus
frequency saved in the chip data, because the controller can be used for
both SPI-transfer-based and SPI-transfer-less communications. From
software point of view keeping the current clock divider in an SPI-device
specific storage may give a small performance gain (to avoid sometimes a
round-up division), but in comparison to the total SPI transfer time it
just doesn't worth saving a few CPU cycles in comparison to the total SPI
transfer time while having the harder to read code. The only optimization,
which could worth preserving in the code is to avoid unnecessary DW SPI
controller registers update if it's possible. So to speak let's simplify
the SPI communication speed update procedure by removing the clock-related
fields from the peripheral chip data and update the DW SPI clock divider
only if it's really changed. The later change is reached by keeping the
effective SPI bus speed in the internal DW SPI private data.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-6-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPI bus speed update functionality will be useful in another parts of
the driver too (like to implement the SPI memory operations and from the
DW SPI glue layers). Let's move it to the update_cr0() method then and
since the later is now updating not only the CTRLR0 register alter its
prototype to have a generic function name not related to CR0.
Leave the too long line with the chip->clk_div setting as is for now,
since it's going to be changed later anyway.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Indeed there is no point in detecting the SPI peripheral device parameters
and initializing the CR0 register fields each time an SPI transfer is
executed. Instead let's define a dedicated CR0 chip-data member, which
will be initialized in accordance with the SPI device settings at the
moment of setting it up.
By doing so we'll finally make the SPI device chip_data serving as it's
supposed to - to preserve the SPI device specific DW SPI configuration.
See spi-fsl-dspi.c, spi-pl022.c, spi-pxa2xx.c drivers for example of the
way the chip data is utilized.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently DWC SSI core is supported by means of setting up the
core-specific update_cr0() callback. It isn't suitable for multiple
reasons. First of all having exported several methods doing the same thing
but for different chips makes the code harder to maintain. Secondly the
spi-dw-core driver exports the methods, then the spi-dw-mmio driver sets
the private data callback with one of them so to be called by the core
driver again. That makes the code logic too complicated. Thirdly using
callbacks for just updating the CR0 register is problematic, since in case
if the register needed to be updated from different parts of the code,
we'd have to create another callback (for instance the SPI device-specific
parameters don't need to be calculated each time the SPI transfer is
submitted, so it's better to pre-calculate the CR0 data at the SPI-device
setup stage).
So keeping all the above in mind let's discard the update_cr0() callbacks,
define a generic and static dw_spi_update_cr0() method and create the
DW_SPI_CAP_DWC_SSI capability, which when enabled would activate the
alternative CR0 register layout.
While at it add the comments to the code path of the normal DW APB SSI
controller setup to make the dw_spi_update_cr0() method looking coherent.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-3-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Simplify the dw_spi_add_host() method a bit by replacing the currently
implemented default set_cs callback setting up and later having it
overwritten by a custom function with direct if-else-based callback
assignment.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20201007235511.4935-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds dev_pm_ops to mtk-nor to support suspend/resume,
auto suspend delay is set to -1 by default.
Accessing registers are only permitted after its clock is enabled
to deal with unknown state of operating clk at probe time.
Signed-off-by: Ikjoon Jang <ikjn@chromium.org>
Link: https://lore.kernel.org/r/20201006155010.v5.4.I68983b582d949a91866163bab588ff3c2a0d0275@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>
If the SPI controller has has_dmamode = true and spi_bitbang_start() fails
in spi_imx_probe(), then the driver must release the DMA channels acquired
in spi_imx_sdma_init() by calling spi_imx_sdma_exit() in the fail path.
Fixes: f62caccd12 ("spi: spi-imx: add DMA support")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Robin Gong <b38343@freescale.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Link: https://lore.kernel.org/r/20201005132229.513119-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>
s3c64xx_spi_hwinit() disables interrupts. In s3c64xx_spi_probe() after
calling s3c64xx_spi_hwinit() they are enabled with the following call.
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-10-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Increase timeout by 30 ms for some wiggle room and set the minimum value
to 100 ms. This ensures a non-zero value for short transfers which
may take less than 1 ms. The timeout value does not affect
performance because it is used with a completion.
Similar formula is used in other drivers e.g. sun4i, sun6i.
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-9-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Make sure the cur_speed value used in s3c64xx_enable_datapath()
to configure DMA channel and in s3c64xx_wait_for_*() to calculate the
transfer timeout is set to the actual value of (half) the clock speed.
Don't change non-CMU case, because no frequency calculation errors have
been reported.
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Suggested-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-8-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Remove descriptions for non-existent fields and fix indentation.
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-7-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Rename S3C64XX_SPI_SLAVE_* to S3C64XX_SPI_CS_* to match documentation.
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201002122243.26849-6-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Report amount of pending data when a transfer stops due to errors.
Report if DMA was used to transfer data and print the status code.
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-5-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Check return values in prepare_dma() and s3c64xx_spi_config() and
propagate errors upwards.
Fixes: 788437273f ("spi: s3c64xx: move to generic dmaengine API")
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-4-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix issues with DMA transfers bigger than 512 bytes on Exynos3250. Without
the patches such transfers fail.
The vendor kernel for ARTIK5 handles CS in a simmilar way.
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201002122243.26849-3-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix issues with DMA transfers bigger than 512 bytes on Exynos3250. Without
the patches such transfers fail to complete. This solution to the problem
is found in the vendor kernel for ARTIK5 boards based on Exynos3250.
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Link: https://lore.kernel.org/r/20201002122243.26849-2-l.stelmach@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
"program" mode on this controller can trigger up to 56 bits of data
shifting. During the operation, data in PRGDATA[0-5] will be
shifted out from MOSI, and data from MISO will be continuously filling
SHREG[0-9].
Currently this mode is used to implement transfer_one_message for 6-byte
full-duplex transfer, but it can execute a transfer for up-to 7 bytes
as long as the last byte is read only.
transfer_one_message is expected to perform full-duplex transfer,
instead of transfer with specific format. mtk_nor_spi_mem_prg is
added here to use this extra byte.
Newer version of this controller can trigger longer data shifting with
shift bytes more than PRGDATA_MAX + SHREG_MAX. This patch is implemented
with that in mind and it checks against both SHREG_MAX and PRG_CNT_MAX
for future support of new controllers.
Patch 3/3 is a fix for:
commit a59b2c7c56 ("spi: spi-mtk-nor: support standard spi properties")
which breaks supports_op logic. But it can't be separated as it depends
on patch 2/3. Fortuantely the broken commit isn't in stable yet.
Chuanhong Guo (3):
spi: spi-mtk-nor: make use of full capability of prg mode
spi: spi-mtk-nor: add helper for checking prg mode ops
spi: spi-mtk-nor: fix op checks in supports_op
drivers/spi/spi-mtk-nor.c | 179 +++++++++++++++++++++++++++++++++-----
1 file changed, 158 insertions(+), 21 deletions(-)
--
2.26.2
_______________________________________________
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linux-arm-kernel@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-arm-kernel
This patch implements the reporting of the effectively used speed_hz for
the transfer by setting xfer->effective_speed_hz.
See the following patch, which adds this feature to the SPI core for more
information:
commit 5d7e2b5ed5 ("spi: core: allow reporting the effectivly used speed_hz for a transfer")
Signed-off-by: Thomas Kopp <thomas.kopp@microchip.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20200921071036.2091-1-thomas.kopp@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
commit a59b2c7c56 ("spi: spi-mtk-nor: support standard spi properties")
tries to inverse the logic of supports_op when adding
spi_mem_default_supports_op check, but it didn't get it done properly.
There are two regressions introduced by this commit:
1. reading ops supported by program mode is rejected.
2. all ops with special controller routines are incorrectly further
checked against program mode.
This commits inverses the logic back:
1. check spi_mem_default_supports_op and reject unsupported ops first.
2. return true for ops with special controller routines.
3. check the left ops against controller program mode.
Fixes: a59b2c7c56 ("spi: spi-mtk-nor: support standard spi properties")
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200924152730.733243-4-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
op checking/resizing logic for the newly added mtk_nor_spi_mem_prg is
more complicated. Add two helper functions for them:
mtk_nor_match_prg: check whether an op is supported by prg mode.
mtk_nor_adj_prg_size: adjust data size for mtk_nor_spi_mem_prg.
mtk_nor_match_prg isn't called yet because supports_op is currently
broken. It'll be used in the next fix commit.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200924152730.733243-3-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
"program" mode on this controller can trigger up to 56 bits of data
shifting. During the operation, data in PRGDATA[0-5] will be
shifted out from MOSI, and data from MISO will be continuously filling
SHREG[0-9].
Currently this mode is used to implement transfer_one_message for 6-byte
full-duplex transfer, but it can execute a transfer for up-to 7 bytes
as long as the last byte is read only.
transfer_one_message is expected to perform full-duplex transfer,
instead of transfer with specific format. mtk_nor_spi_mem_prg is
added here to use this extra byte.
Newer version of this controller can trigger longer data shifting with
shift bytes more than PRGDATA_MAX + SHREG_MAX. This patch is implemented
with that in mind and it checks against both SHREG_MAX and PRG_CNT_MAX
for future support of new controllers.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200924152730.733243-2-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Since commit d5fab59cab ("spi: atmel: trivial: remove unused fields in
DMA structure"), the driver is not using any definitions from
linux/platform_data/dma-atmel.h, stop including it.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200930145353.3043699-1-alexandre.belloni@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Originally I intended to merge a dedicated Baikal-T1 System Boot SPI
Controller driver into the kernel and leave the DW APB SSI driver
untouched. But after a long discussion (see the link at the bottom of the
letter) Mark and Andy persuaded me to integrate what we developed there
into the DW APB SSI core driver to be useful for another controllers,
which may have got the same peculiarities/problems as ours:
- No IRQ.
- No DMA.
- No GPIO CS, so a native CS is utilized.
- small Tx/Rx FIFO depth.
- Automatic CS assertion/de-assertion.
- Slow system bus.
All of them have been fixed in the framework of this patchset in some
extent at least for the SPI memory operations. As I expected it wasn't
that easy and the integration took that many patches as you can see from
the subject. Though some of them are mere cleanups or weakly related with
the subject fixes, but we just couldn't leave the code as is at some
places since we were working with the DW APB SSI driver anyway. Here is
what we did to fix the original DW APB SSI driver, to make it less messy.
First two patches are just cleanups to simplify the DW APB SSI device
initialization a bit. We suggest to discard the IRQ threshold macro as
unused and use a ternary operator to initialize the set_cs callback
instead of assigning-and-updating it.
Then we've discovered that the n_bytes field of the driver private data is
used by the DW APB SSI IRQ handler, which requires it to be initialized
before the SMP memory barrier and to be visible from another CPUs. Speaking
about the SMP memory barrier. Having one right after the shared resources
initialization is enough and there is no point in using the spin-lock to
protect the Tx/Rx buffer pointers. The protection functionality is
redundant there by the driver design. (Though I have a doubt whether the
SMP memory barrier is also required there because the normal IO-methods
like readl/writel implies a full memory barrier. So any memory operations
performed before them are supposed to be seen by devices and another CPUs.
See the patch log for details of my concern.)
Thirdly we've found out that there is some confusion in the IRQs
masking/unmasking/clearing in the SPI-transfer procedure. Multiple interrupts
are unmasked on the SPI-transfer initialization, but just TXEI is only
masked back on completion. Similarly IRQ status isn't cleared on the
controller reset, which actually makes the reset being not full and errors
prone in the controller probe procedure.
Another very important optimization is using the IO-relaxed accessors in
the dw_read_io_reg()/dw_write_io_reg() methods. Since the Tx/Rx FIFO data
registers are the most frequently accessible controller resource, using
relaxed accessors there will significantly improve the data read/write
performance. At least on Baikal-T1 SoC such modification opens up a way to
have the DW APB SSI controller working with higher SPI bus speeds, than
without it.
Fifthly we've made an effort to cleanup the code using the SPI-device
private data - chip_data. We suggest to remove the chip type from there
since it isn't used and isn't implemented right anyway. Then instead of
having a bus speed, clock divider, transfer mode preserved there, and
recalculating the CR0 fields of the SPI-device-specific phase, polarity
and frame format each time the SPI transfer is requested, we can save it
in the chip_data instance. By doing so we'll make that structure finally
used as it was supposed to by design (see the spi-fsl-dspi.c, spi-pl022.c,
spi-pxa2xx.c drivers for examples).
Sixthly instead of having the SPI-transfer specific CR0-update callback,
we suggest to implement the DW APB SSI controller capabilities approach.
By doing so we can now inject the vendor-specific peculiarities in
different parts of the DW APB SSI core driver (which is required to
implement both SPI-transfers and the SPI memory operations). This will
also make the code less confusing like defining a callback in the core
driver, setting it up in the glue layer, then calling it from the core
driver again. Seeing the small capabilities implementation embedded
in-situ is more readable than tracking the callbacks assignments. This
will concern the CS-override, Keembay master setup, DW SSI-specific CR0
registers layout capabilities.
Seventhly since there are going to be two types of the transfers
implemented in the DW APB SSI core driver, we need a common method to set
the controller configuration like, Tx/Rx-mode, bus speed, data frame size
and number of data frames to read in case of the memory operations. So we
just detached the corresponding code from the SPI-transfer-one method and
made it to be a part of the new dw_spi_update_config() function, which is
former update_cr0(). Note that the new method will be also useful for the
glue drivers, which due to the hardware design need to create their own
memory operations (for instance, for the dirmap-operations provided in the
Baikal-T System Boot SPI controller driver).
Eighthly it is the data IO procedure and IRQ-based SPI-transfer
implementation refactoring. The former one will look much simpler if the
buffers initial pointers and the buffers length data utilized instead of
the Tx/Rx buffers start and end pointers. The later one currently lacks of
valid execution at the final stage of the SPI-transfer. So if there is no
data left to send, but there is still data which needs to be received, the
Tx FIFO Empty IRQ will constantly happen until all of the requested
inbound data is received. So we suggest to fix that by taking the Rx FIFO
Empty IRQ into account.
Ninthly it's potentially errors prone to enable the DW APB SSI interrupts
before enabling the chip. It specifically concerns a case if for some
reason the DW APB SSI IRQs handler is executed before the controller is
enabled. That will cause a part of the outbound data loss. So we suggest
to reverse the order.
Tenthly in order to be able to pre-initialize the Tx FIFO with data and
only the start the SPI memory operations we need to have any CS
de-activated. We'll fulfil that requirement by explicitly clearing the CS
on the SPI transfer completion and at the explicit controller reset.
Then seeing all the currently available and potentially being created
types of the SPI transfers need to perform the DW APB SSI controller
status register check and the errors handler procedure, we've created a
common method for all of them.
Eleventhly if before we've mostly had a series of fixups, cleanups and
refactorings, here we've finally come to the new functionality
implementation. It concerns the poll-based transfer (as Baikal-T1 System
Boot SPI controller lacks a dedicated IRQ lane connected) and the SPI
memory operations implementation. If the former feature is pretty much
straightforward (see the patch log for details), the later one is a bit
tricky. It's based on the EEPROM-read (write-then-read) and the Tx-only
modes of the DW APB SSI controller, which as performing the automatic data
read and write let's us to implement the faster IO procedure than using
the Tx-Rx-mode-based approach. Having the memory-operations implemented
that way is the best thing we can currently do to provide the errors-less
SPI transfers to SPI devices with native CS attached.
Note the approach utilized here to develop the SPI memory operations can
be also used to create the "automatic CS toggle problem"-free(ish) SPI
transfers (combine SPI-message transfers into two buffers, disable
interrupts, push-pull the combined data). But we don't provide a solution
in the framework of this patchset. It is a matter of a dedicated one,
which we currently don't intend to spend our time on.
Finally at the closure of the this patchset you'll find patches, which
provide the Baikal-T1-specific DW APB SSI controllers support. The SoC has
got three SPI controllers. Two of them are pretty much normal DW APB SSI
interfaces: with IRQ, DMA, FIFOs of 64 words depth, 4x CSs. But the third
one as being a part of the Baikal-T1 System Boot Controller has got a very
limited resources: no IRQ, no DMA, only a single native chip-select and
Tx/Rx FIFOs with just 8 words depth available. In order to provide a
transparent initial boot code execution the System Boot SPI Controller is
also utilized by an vendor-specific IP-block, which exposes an SPI flash
memory direct mapping interface. Please see the corresponding patch for
details.
Link: https://lore.kernel.org/linux-spi/20200508093621.31619-1-Sergey.Semin@baikalelectronics.ru/
[1] "LINUX KERNEL MEMORY BARRIERS", Documentation/memory-barriers.txt,
Section "KERNEL I/O BARRIER EFFECTS"
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Cc: wuxu.wu <wuxu.wu@huawei.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Serge Semin (30):
spi: dw: Discard IRQ threshold macro
spi: dw: Use ternary op to init set_cs callback
spi: dw: Initialize n_bytes before the memory barrier
Revert: spi: spi-dw: Add lock protect dw_spi rx/tx to prevent
concurrent calls
spi: dw: Clear IRQ status on DW SPI controller reset
spi: dw: Disable all IRQs when controller is unused
spi: dw: Use relaxed IO-methods to access FIFOs
spi: dw: Discard DW SSI chip type storages
spi: dw: Convert CS-override to DW SPI capabilities
spi: dw: Add KeemBay Master capability
spi: dw: Add DWC SSI capability
spi: dw: Detach SPI device specific CR0 config method
spi: dw: Update SPI bus speed in a config function
spi: dw: Simplify the SPI bus speed config procedure
spi: dw: Update Rx sample delay in the config function
spi: dw: Add DW SPI controller config structure
spi: dw: Refactor data IO procedure
spi: dw: Refactor IRQ-based SPI transfer procedure
spi: dw: Perform IRQ setup in a dedicated function
spi: dw: Unmask IRQs after enabling the chip
spi: dw: Discard chip enabling on DMA setup error
spi: dw: De-assert chip-select on reset
spi: dw: Explicitly de-assert CS on SPI transfer completion
spi: dw: Move num-of retries parameter to the header file
spi: dw: Add generic DW SSI status-check method
spi: dw: Add memory operations support
spi: dw: Introduce max mem-ops SPI bus frequency setting
spi: dw: Add poll-based SPI transfers support
dt-bindings: spi: dw: Add Baikal-T1 SPI Controllers
spi: dw: Add Baikal-T1 SPI Controller glue driver
.../bindings/spi/snps,dw-apb-ssi.yaml | 33 +-
drivers/spi/Kconfig | 29 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-dw-bt1.c | 339 +++++++++
drivers/spi/spi-dw-core.c | 642 ++++++++++++++----
drivers/spi/spi-dw-dma.c | 16 +-
drivers/spi/spi-dw-mmio.c | 36 +-
drivers/spi/spi-dw.h | 85 ++-
8 files changed, 960 insertions(+), 221 deletions(-)
create mode 100644 drivers/spi/spi-dw-bt1.c
--
2.27.0
There is no point in having the commit 19b61392c5 ("spi: spi-dw: Add
lock protect dw_spi rx/tx to prevent concurrent calls") applied. The
commit author made an assumption that the problem with the rx data
mismatch was due to the lack of the data protection. While most likely it
was caused by the lack of the memory barrier. So having the
commit bfda044533 ("spi: dw: use "smp_mb()" to avoid sending spi data
error") applied would be enough to fix the problem.
Indeed the spin unlock operation makes sure each memory operation issued
before the release will be completed before it's completed. In other words
it works as an implicit one way memory barrier. So having both smp_mb()
and the spin_unlock_irqrestore() here is just redundant. One of them would
be enough. It's better to leave the smp_mb() since the Tx/Rx buffers
consistency is provided by the data transfer algorithm implementation:
first we initialize the buffers pointers, then make sure the assignments
are visible by the other CPUs by calling the smp_mb(), only after that
enable the interrupt, which handler uses the buffers.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
In a further commit we'll have to get rid of the update_cr0() callback and
define a DW SSI capability instead. Since Keem Bay master/slave
functionality is controller by the CTRL0 register bitfield, we need to
first move the master mode selection into the internal corresponding
update_cr0 method, which would be activated by means of the dedicated
DW_SPI_CAP_KEEMBAY_MST capability setup.
Note this will be also useful if the driver will be ever altered to
support the DW SPI slave interface.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-11-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
There are several vendor-specific versions of the DW SPI controllers,
each of which may have some peculiarities with respect to the original
IP-core. Seeing it has already caused adding flags and a callback into the
DW SPI private data, let's introduce a generic capabilities interface to
tune the generic DW SPI controller driver up in accordance with the
particular controller specifics. It's done by converting a simple
Alpine-specific CS-override capability into the DW SPI controller
capability activated by setting the DW_SPI_CAP_CS_OVERRIDE flag.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-10-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
