The BCM2835 AUX SPI has a shared interrupt line (with AUX UART).
Downstream fixes this with an AUX irqchip to demux the IRQ sources and a
DT change which breaks compatibility with older kernels. The AUX irqchip
was already rejected for upstream[1] and the DT change would break
working systems if the DTB is updated to a newer one. The latter issue
was brought to my attention by Alex Graf.
The root cause however is a bug in the shared handler. Shared handlers
must check that interrupts are actually enabled before servicing the
interrupt. Add a check that the TXEMPTY or IDLE interrupts are enabled.
[1] https://patchwork.kernel.org/patch/9781221/
Cc: Alexander Graf <agraf@suse.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: linux-spi@vger.kernel.org
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
Always confirm the BSPI_MAST_N_BOOT_CTRL bit when enabling
or disabling BSPI transfers.
Fixes: 4e3b2d236f ("spi: bcm-qspi: Add BSPI spi-nor flash controller driver")
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Added fix for probing of spi-nor device non-zero chip selects. Set
MSPI_CDRAM_PCS (peripheral chip select) with spi master for MSPI
controller and not for MSPI/BSPI spi-nor master controller. Ensure
setting of cs bit in chip select register on chip select change.
Fixes: fa236a7ef2 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Currently the 32-bit device address only is supported for DMA. However,
starting from Intel Sunrisepoint PCH the DMA address of the device FIFO
can be 64-bit.
Change the respective variable to be compatible with DMA engine
expectations, i.e. to phys_addr_t.
Fixes: 34cadd9c1b ("spi: pxa2xx: Add support for Intel Sunrisepoint")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
In case of xspi work in busy condition, may send bytes failed.
once something wrong, spi controller did't work any more
My test found this situation appear in both of read/write process.
so when TX FIFO is full, add one byte delay before send data;
Signed-off-by: sxauwsk <sxauwsk@163.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The change fixes a bit field overflow which allows to write to higher
bits while calculating SPI transfer clock and setting BRPS and BRDV
bit fields, the problem is reproduced if 'parent_rate' to 'spi_hz'
ratio is greater than 1024, for instance
p->min_div = 2,
MSO rate = 33333333,
SPI device rate = 10000
results in
k = 5, i.e. BRDV = 0b100 or 1/32 prescaler output,
BRPS = 105,
TSCR value = 0x6804, thus MSSEL and MSIMM bit fields are non-zero.
Fixes: 65d5665bb2 ("spi: sh-msiof: Update calculation of frequency dividing")
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now i.MX SPI controller can work in Slave mode.
Update MODULE_DESCRIPTION to "SPI Controller driver".
Signed-off-by: wangbo <wang.bo116@zte.com.cn>
Signed-off-by: Mark Brown <broonie@kernel.org>
A quiet release for SPI, some fixes and small updates for individual
drivers with one bigger change from Linus Walleij which coverts the
bitbanging SPI driver to use the GPIO descriptor API from Linus Walleij.
Since GPIO descriptors were used by platform data this means there's a
few changes in arch/ making relevant updates for a few platforms and one
misc driver that are affected.
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Merge tag 'spi-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull SPI updates from Mark Brown:
"A quiet release for SPI, some fixes and small updates for individual
drivers with one bigger change from Linus Walleij which coverts the
bitbanging SPI driver to use the GPIO descriptor API from Linus
Walleij.
Since GPIO descriptors were used by platform data this means there's a
few changes in arch/ making relevant updates for a few platforms and
one misc driver that are affected"
* tag 'spi-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (24 commits)
MAINTAINERS: update Andi's e-mail
spi: spi-atmel: Use correct enum for DMA transfer direction
spi: sh-msiof: Document R-Car M3-N support
spi: sh-msiof: Use correct enum for DMA transfer direction
spi: sprd: Add the support of restarting the system
spi: sprd: Simplify the transfer function
spi: Fix unregistration of controller with fixed SPI bus number
spi: rspi: use correct enum for DMA transfer direction
spi: jcore: disable ref_clk after getting its rate
spi: bcm-qspi: fIX some error handling paths
spi: pxa2xx: Disable runtime PM if controller registration fails
spi: tegra20-slink: use true and false for boolean values
spi: Fix scatterlist elements size in spi_map_buf
spi: atmel: init FIFOs before spi enable
spi: orion: Prepare space for per-child options
spi: orion: Make the error message greppable
spi: orion: Rework GPIO CS handling
spi: bcm2835aux: Avoid 64-bit arithmetic in xfer len calc
spi: spi-gpio: Augment device tree bindings
spi: spi-gpio: Rewrite to use GPIO descriptors
...
Use enum dma_transfer_direction as required by the functions
dmaengine_prep_slave_(sg|single)() instead of enum dma_data_direction.
This won't change behavior in practice as the enum values are
equivalent.
This fixes two warnings when building with clang:
drivers/spi/spi-atmel.c:771:12: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction'
[-Wenum-conversion]
DMA_FROM_DEVICE,
^~~~~~~~~~~~~~~
...
Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
The blackfin architecture is getting removed, so these
won't be needed any more.
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Aaron Wu <aaron.wu@analog.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
A lot of Kconfig symbols have architecture specific dependencies.
In those cases that depend on architectures we have already removed,
they can be omitted.
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Use enum dma_transfer_direction as required by dmaengine_prep_slave_sg()
instead of enum dma_data_direction. This won't change behavior in
practice as the enum values are equivalent.
This fixes two warnings when building with clang:
drivers/spi/spi-sh-msiof.c:755:27: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction' [-Wenum-conversion]
rx->sgl, rx->nents, DMA_FROM_DEVICE,
^~~~~~~~~~~~~~~
drivers/spi/spi-sh-msiof.c:772:27: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction' [-Wenum-conversion]
tx->sgl, tx->nents, DMA_TO_DEVICE,
^~~~~~~~~~~~~
Based on commit 768d59f5d0 ("spi: rspi: use correct enum for DMA
transfer direction").
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Mark Brown <broonie@kernel.org>
On Spreadtrum platform, we use one PMIC watchdog to reset the whole system
with loading one suitable timeout value (usually 50ms) for the watchdog.
In theory, we should implement the restart function in drivers/power/reset
subsystem to access the PMIC watchdog with regmap. When restart the system,
other cores will be stopped by IPI, but if other cores were accessing PMIC
with holding the regmap mutex lock, that will cause dead-lock issue if we
try to access the PMIC watchdog with regmap to restart the whole system.
Thus we can implement the restart function in ADI driver to avoid this
issue.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
We can move the hardware spinlock protection into the ADI read/write
functions to simplify the sprd_adi_transfer_one() function. Moreover
this optimization can also help to access PMIC without considering
the hardware spinlock using sprd_adi_read/write() functions.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
ceased to unregister SPI buses with fixed bus numbers. Moreover this is
visible only if CONFIG_SPI_DEBUG=y is set or when trying to re-register
the same SPI controller.
rmmod spi_pxa2xx_platform (with CONFIG_SPI_DEBUG=y):
[ 26.788362] spi_master spi1: attempting to delete unregistered controller [spi1]
modprobe spi_pxa2xx_platform:
[ 37.883137] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:19.0/pxa2xx-spi.12/spi_master/spi1'
[ 37.894984] CPU: 1 PID: 1467 Comm: modprobe Not tainted 4.16.0-rc4+ #21
[ 37.902384] Call Trace:
...
[ 38.122680] kobject_add_internal failed for spi1 with -EEXIST, don't try to register things with the same name in the same directory.
[ 38.136154] WARNING: CPU: 1 PID: 1467 at lib/kobject.c:238 kobject_add_internal+0x2a5/0x2f0
...
[ 38.513817] pxa2xx-spi pxa2xx-spi.12: problem registering spi master
[ 38.521036] pxa2xx-spi: probe of pxa2xx-spi.12 failed with error -17
Fix this by not returning immediately from spi_unregister_controller() if
idr_find() doesn't find controller with given ID/bus number. It finds
only those controllers that were registered with dynamic SPI bus
numbers. Only conditional cleanup between dynamic and fixed bus numbers
is to remove allocated IDR.
Fixes: 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
Cc: stable@vger.kernel.org
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use enum dma_transfer_direction as required by dmaengine_prep_slave_sg
instead of enum dma_data_direction. This won't change behavior in
practice as the enum values are equivalent.
This fixes two warnings when building with clang:
drivers/spi/spi-rspi.c:538:26: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction' [-Wenum-conversion]
rx->sgl, rx->nents, DMA_FROM_DEVICE,
^~~~~~~~~~~~~~~
drivers/spi/spi-rspi.c:558:26: warning: implicit conversion from enumeration
type 'enum dma_data_direction' to different enumeration type
'enum dma_transfer_direction' [-Wenum-conversion]
tx->sgl, tx->nents, DMA_TO_DEVICE,
^~~~~~~~~~~~~
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver does not disable ref_clk on remove.
According to the comment, the only reason to enable the clock is to get
its rate. So, it should be safe to disable clk just after that.
By the way, clk_prepare_enable() looks to be more appropriate
than clk_enable() here.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>
For some reason, commit c0368e4db4 ("spi: bcm-qspi: Fix use after free
in bcm_qspi_probe() in error path") has updated some gotos, but not all of
them.
This looks spurious, so fix it.
Fixes: fa236a7ef2 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Don't leave runtime PM enabled in case devm_spi_register_controller()
returns with an error. Otherwise runtime PM will complain when driver is
reloaded:
[ 693.855811] pxa2xx-spi pxa2xx-spi.13: Unbalanced pm_runtime_enable!
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Assign true or false to boolean variables instead of an integer value.
This issue was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
When SPI transfers can be offloaded using DMA, the SPI core need to
build a scatterlist to make sure that the buffer to be transferred is
dma-able.
This patch fixes the scatterlist entry size computation in the case
where the maximum acceptable scatterlist entry supported by the DMA
controller is less than PAGE_SIZE, when the buffer is vmalloced.
For each entry, the actual size is given by the minimum between the
desc_len (which is the max buffer size supported by the DMA controller)
and the remaining buffer length until we cross a page boundary.
Fixes: 65598c13fd ("spi: Fix per-page mapping of unaligned vmalloc-ed buffer")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
The datasheet recommends initializing FIFOs before
SPI enable. If we do not do it like this, there may be
a strange behavior. We noticed that DMA does not work properly
with FIFOs if we do not clear them beforehand or enable them
before SPIEN.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Aggregating all options for a particular child underneath a common
struct looks cleaner compared to having a separate array for each
per-child option.
Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 544248623b introduced a new user-visible string which was
however split into two chunks. Thanks to Mark Brown for noticing.
Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
- Claim the GPIO from the driver, not via DT bindings or through the
platform code
- Find an unused HW CS signal because Orion needs to drive one for each
SPI transaction
The spi-orion.c was the only driver which supported (or cared about) the
CS GPIO, while it wasn't actually requesting it. This change means that
the DT bindings should stop hogging the GPIO CS pins because it's now
being handled by the driver.
Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
We want to check for xfers that are over 30 microseconds. Rather than
find how many µs a xfer will take, instead find how many bytes can be
transferred in 30 µs. The latter must be less than 32 bits (since our
clock speed is limited to 32 bits), while the former involves 64 bit
quantities and more arithmetic operations.
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This converts the bit-banged GPIO SPI driver to looking up and
using GPIO descriptors to get a handle on GPIO lines for SCK,
MOSI, MISO and all CS lines.
All existing board files are converted in one go to keep it all
consistent. With these conversions I rarely find any interrim
steps that makes any sense.
Device tree probing and GPIO handling should work like before
also after this patch.
For board files, we stop using controller data to pass the GPIO
line for chip select, instead we pass this as a GPIO descriptor
lookup like everything else.
In some s3c24xx machines the names of the SPI devices were set to
"spi-gpio" rather than "spi_gpio" which can never have worked, I
fixed it working (I guess) as part of this patch set. Sometimes
I wonder how this code got upstream in the first place, it
obviously is not tested.
mach-s3c64xx/mach-smartq.c has the same problem and additionally
defines the *same* GPIO line for MOSI and MISO which is not going
to be accepted by gpiolib. As the lines were number 1,2,2 I assumed
it was a typo and use lines 1,2,3. A comment gives awat that line 0
is chip select though no actual SPI device is provided for the LCD
supposed to be on this bit-banged SPI bus. I left it intact instead
of just deleting the bus though.
Kill off board file code that try to initialize the SPI lines
to the same values that they will later be set by the spi_gpio
driver anyways. Given the huge number of weird things in these
board files I do not think this code is very tested or put in
with much afterthought anyways.
In order to assert that we do not get performance regressions on
this crucial bing-banged driver, a ran a script like this dumping the
Ilitek ILI9322 regmap 10000 times (it has no caching obviously) on
an otherwise idle system in two iterations before and after the
patches:
#!/bin/sh
for run in `seq 10000`
do
cat /debug/regmap/spi0.0/registers > /dev/null
done
Before the patch:
time test.sh
real 3m 41.03s
user 0m 29.41s
sys 3m 7.22s
time test.sh
real 3m 44.24s
user 0m 32.31s
sys 3m 7.60s
After the patch:
time test.sh
real 3m 41.32s
user 0m 28.92s
sys 3m 8.08s
time test.sh
real 3m 39.92s
user 0m 30.20s
sys 3m 5.56s
So any performance differences seems to be in the error margin.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Convert to generalized SPI controller API introduced by the
commit 8caab75fd2 ("spi: Generalize SPI "master" to "controller"").
Inside driver variable name "master" is still used to indicate the driver
is master only.
While at it, change "unsigned cs" to "unsigned int cs" in
pxa2xx_spi_fw_translate_cs() to suppress checkpatch warning.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Convert to generalized SPI controller API introduced by the
commit 8caab75fd2 ("spi: Generalize SPI "master" to "controller"").
Inside driver variable name "master" is still used to indicate the driver
is master only.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The AVR32 symbol was removed in commit 26202873bb ("avr32: remove
support for AVR32 architecture").
Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Move SSP idle waiting before CS deassert from error and end of message
handling function giveback() to cs_deassert(). This ensures idle waiting
is done also if there is CS change between transfers.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Local struct chip_data has two members that are not used:
- cs. Looks like was never used
- enable_dma. Became unused by the commit f89a6d8f43 ("spi: dw-mid: move
to use core SPI DMA mappings").
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If the optional "axi" clk is deferred, we still need to undo some
initialisation. Especially 'master' must be released. It will be
reallocated the next time 'orion_spi_probe()' is called.
Add a new label to clean what needs to be cleaned and rename another
label to improve the names used.
Fixes: 92ae112e47 ("spi: orion: Fix clock resource by adding an optional bus clock")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixes the following sparse warnings :
line 767: warning: incorrect type in assignment (different base types)
line 767: expected unsigned int [unsigned] [assigned] [usertype] val_out
line 767: got restricted __le32 [usertype] <noident>
line 776: warning: cast to restricted __le32
This takes advantage of readl/writel to do the endianness reordering,
and removes an extra variable in the function.
Fixes: f68a7dcb91 ("spi: a3700: Add full-duplex support")
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixes the following sparse warnings :
line 504: warning: incorrect type in assignment (different base types)
line 504: expected unsigned int [unsigned] [usertype] val
line 504: got restricted __le32 [usertype] <noident>
line 527: warning: cast to restricted __le32
This is solved by removing endian-converson functions, since the
converted values are going through readl/writel anyway, which take care
of the conversion.
Fixes: 6fd6fd68c9 ("spi: armada-3700: Fix padding when sending not 4-byte aligned data")
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The armada 3700 SPI controller has support for full-duplex transfers,
but it can only be done without using the hardware FIFOs.
A full duplex transfer is done by shifting 4 bytes at a time, or even
one byte at a time for transfers less than 4 bytes long.
While this method is perfectly suitable for small transfers, it is still
slower than using the FIFOs.
This commit implement full-duplex support, making sure that half-duplex
transfers are still done using the FIFOs with the existing method.
Some setup functions were moved around to make sure the controller is
properly configured before beginning each transfer.
This was tested on EspressoBin with a logical analyser, and a simple
setup where MISO is connected on MOSI. Transfers were made from
userspace using spidev and spi-pipe from the spi-tools project
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
The armada 3700 SPI controller allows to make transfers without using
the 32 bytes RFIFO and WFIFO.
This commit enable switching between FIFO and non-FIFO mode, which is
necessary to implement full-duplex transfers.
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Armada 3700 SPI controller has an internal clock divider which can
divide the parent clock frequency by up to 30.
This patch sets the limits in the spi_controller fields so that we can
detect when a non-supported frequency is requested by a device for a
transfer.
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
When performing a read using FIFO mode, the spi controller shifts out
the last 2 bytes that were written in a previous transfer on MOSI.
This undocumented behaviour can cause devices to misinterpret the
transfer, so we explicitly clear the WFIFO before each read.
This behaviour was noticed on EspressoBin.
Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
On Armada 7K/8K we need to explicitly enable the bus clock. The bus clock
is optional because not all the SoCs need them but at least for Armada
7K/8K it is actually mandatory.
The binding documentation is updating accordingly as well as mentioning
the mandatory clock which was also missing.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace the original license statement with the SPDX identifier.
Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Rob Herring