The spec for the pca9546 was missing. This chip is the same as the pca9545
except that it lacks interrupt lines. While the i2c_device_id table mapped
the pca9546 to the pca9545 definition the compatible table did not.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Peter Rosin <peda@axentia.se>
In ACPI world any ID should be carefully chosen and registered
officially. The commit bbf9d262a1 seems did a wrong assumption because
PCA is the registered PNP ID for "PHILIPS BU ADD ON CARD". I'm pretty
sure this prefix has nothing to do with the driver in question.
Moreover, newer ACPI specification has a support of _DSD method and
special device IDs to allow drivers be enumerated via compatible string.
The slight change to support this kind of enumeration will be added in
sequential patch against pca954x.c.
Revert the commit bbf9d262a1 for good.
Cc: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
This reverts commit b0c1e95ab4. It
contains a flaw and the next version has more features added which makes
me want to move it to the next cycle.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This reverts commit 02dbfa5e55. I grabbed
the wrong version from the list and will pull the proper one from Peter
Rosin's mux tree.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
After commit 7999eecb7e ("i2c: exynos5: fix arbitration lost handling"),
some I2C transactions are failing because the TRANSFER_DONE_AUTO field is
not set in the I2C_TRANS_STATUS register so the i2c->status value is left
to -EINVAL causing the i2c->msg_complete completion to never be signaled.
For example, when reading the time of an I2C rtc on an Exynos5800 machine:
$ cat /sys/class/rtc/rtc0/time
[ 25.924594] exynos5-hsi2c 12e10000.i2c: rx timeout
[ 65.028365] max77686-rtc max77802-rtc: Fail to read time reg(-22)
cat: /sys/class/rtc/rtc0/time: Invalid argument
The Exynos5422 manual states clearly that most I2C_TRANS_STATUS reg bits
(including TRANSFER_DONE_AUTO) are cleared after the register is read. So
reading has side effects and should only be done if HSI2C_INT_I2C was set.
Fixes: 7999eecb7e ("i2c: exynos5: fix arbitration lost handling")
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some platforms like hi3660 need do reset first to allow accessing registers
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Ramiro Oliveira <ramiro.oliveira@synopsys.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This will allow marking device property lists as __initdata, the same as
board info structures themselves.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
All length fields in Linux I2C are u16, so a HW length limitation of 16
bit lengths is not a limitation. Remove the quirk structure.
Tested-by: Jun Gao <jun.gao@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The BSC data buffers to send and receive data are each of size 32 bytes
or 8 bytes 'xfersz' depending on SoC. The problem observed for all the
combined message transfer was if length of data transfer was a multiple
of 'xfersz' a repeated START was being transmitted by BSC driver. Fixed
this by appropriately setting START/STOP conditions for such transfers.
Fixes: dd1aa2524b ("i2c: brcmstb: Add Broadcom settop SoC i2c controller driver")
Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Acked-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Refcount of of_node is increased with of_node_get() in i2c_mux_add_adapter().
It must be decreased with of_node_put() in i2c_mux_del_adapters().
Signe-off-by: Qi Hou <qi.hou@windriver.com>
Reviewed-by: Zhang Xiao <xiao.zhang@windriver.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
While modifying the driver to use the STOP interrupt, the completion of the
intermediate transfers need to wake the driver back up in order to initiate
the next transfer (restart condition). Otherwise you get never ending
interrupts and only the first transfer sent.
Fixes: 71ccea095e ("i2c: riic: correctly finish transfers")
Reported-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Refcount of of_node is increased with of_node_get() in i2c_mux_add_adapter().
It must be decreased with of_node_put() in i2c_mux_del_adapters().
Cc: stable@vger.kernel.org
Signed-off-by: Qi Hou <qi.hou@windriver.com>
Reviewed-by: Zhang Xiao <xiao.zhang@windriver.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Using pci_alloc_irq_vectors() instead of the deprecated
pci_enable_msix() allows to remove the msix_entry from
struct octeon_i2c and thus to get rid of the config symbol check.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In case of arbitration lost adequate interrupt sometimes is not signaled.
As a result transfer timeouts and is not retried, as it should. To avoid
such cases code is added to check transaction status in case of every
interrupt.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fifo-almost-empty irq signal should be disabled as soon as possible,
to avoid unnecessary interrupt storm. The best moment is when there is
no more data to feed fifo.
This patch fixes system stalls caused by IRQ storm.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When going to suspend, the I2C registers may be lost because the power to
VDDcore is cut. Restore them when resuming.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since commit e247454103 ("bcm2835: Fix hang for writing messages
larger than 16 bytes") the interrupt handler is prone to a possible
NULL pointer dereference. This could happen if an interrupt fires
before curr_msg is set by bcm2835_i2c_xfer_msg() and randomly occurs
on the RPi 3. Even this is an unexpected behavior the driver must
handle that with an error instead of a crash.
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Fixes: e247454103 ("bcm2835: Fix hang for writing messages larger than 16 bytes")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add Tegra BPMP I2C driver. The BPMP is the boot and power management
processor embedded in Tegra SoCs. In newer SoC versions, access to one
of the I2C busses goes via the BPMP, requiring a different "proxy" I2C
driver that accesses the bus via the real I2C driver embedded in the
BPMP firmware.
Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This reverts commit 63d0f0a695.
It caused a regression on platforms where I2C controller is synthesized
with dynamic TAR update disabled. Detection code is testing is bit
DW_IC_CON_10BITADDR_MASTER in register DW_IC_CON read-only but fails to
restore original value in case bit is read-write.
Instead of fixing this we revert the commit since it was preparation for
the commit 0317e6c0f1 ("i2c: designware: do not disable adapter after
transfer") which was also reverted.
Reported-by: Shah Nehal-Bakulchandra <Nehal-bakulchandra.Shah@amd.com>
Reported-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-By: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: <stable@vger.kernel.org> # v4.9+
Fixes: 63d0f0a695 ("i2c: designware: detect when dynamic tar update is possible")
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Various muxes can aggregate multiple interrupts from each i2c bus.
All of the muxes with interrupt support combine the active low irq lines
using an internal 'and' function and generate a combined active low
output. The muxes do provide the ability to read a control register to
determine which irq is active. By making the mux an irq controller isr
latency can potentially be reduced by reading the status register and
then only calling the registered isr on that bus segment.
As there is no irq masking on the mux irq are disabled until irq_unmask is
called at least once.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Peter Rosin <peda@axentia.se>
The spec for the pca954x was missing. This chip is the same as the pca9540
except that it has interrupt lines. While the i2c_device_id table mapped
the pca9542 to the pca9540 definition the compatible table did not. In
preparation for irq support add the pca9542 definition.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Peter Rosin <peda@axentia.se>
This fixes the condition where the controller has not fully completed its
final transfer and leaves the bus and controller in a undesirable state.
At the end of the last transmitted byte, the existing driver would just
signal for a STOP condition to be transmitted then immediately signal
completion. However, the full STOP procedure might not have fully taken
place by the time the runtime PM shuts off the peripheral clock, leaving
the bus in a suspended state.
Alternatively, the STOP condition on the bus may have completed, but when
the next transaction is requested by the upper layer, not all the
necessary register cleanup was finished from the last transfer which made
the driver return BUS BUSY when it really wasn't.
This patch now makes all transmit and receive transactions wait for the
STOP condition to fully complete before signaling a completed transaction.
With this new method, runtime PM no longer seems to be an issue.
Fixes: 310c18a414 ("i2c: riic: add driver")
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Intel Gemini Lake has the same SMBus host controller than Intel Broxton.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Remove including <linux/version.h> that don't need it.
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
SMBSLVCNT must be protected with the piix4_mutex_sb800 in order to avoid
multiple buses accessing to the semaphore at the same time.
Fixes: 701dc207bf ("i2c: piix4: Avoid race conditions with IMC")
Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since '701dc207bf55 ("i2c: piix4: Avoid race conditions with IMC")' we
are using the SMBSLVCNT register at offset 0x8. We need to request it.
Fixes: 701dc207bf ("i2c: piix4: Avoid race conditions with IMC")
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Declare i2c_algorithm structures as const as they are only stored in the
algo field of an i2c_adapter structure. This field is of type const, so
i2c_algorithm structures having this property can be made const too.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> for
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
With many drivers converting to using generic device properties, it is
useful to provide array of device properties when instantiating new i2c
client via i2c_board_info and have them automatically added to the device
in question.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When using devicetree i2c_board_info.type is set to the compatible
string with the vendor prefix removed. For I2C devices described via
ACPI the i2c_board_info.type string is set to the ACPI device name. When
using ACPI and DT ids this string ends up something like "PRP0001:00".
If the of_compatible property is present try to use that instead. This
makes it easier to instantiate i2c drivers through ACPI with DT ids.
Signed-off-by: Dan O'Donovan <dan@emutex.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If an i2c access through i2c-cros-ec-tunnel returns an error, the following
log message is seen on the console.
cros-ec-i2c-tunnel ff200000.spi:ec@0:i2c-tunnel:
Error parsing EC i2c message -121
This can happen a lot if, for example, the i2c-detect command is executed.
Since it is perfectly normal for an i2c controller to report an error,
drop the message. Also, report -ENXIO instead of -EREMOTEIO if the access
error is due to NAK from the device, and return -EIO instead of -EREMOTEIO
for other errors, as suggested in Documentation/i2c/fault-codes.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This function has the purpose of mode detection by checking the
device nodes for a reg matching with the I2C_OWN_SLAVE_ADDREESS flag.
Currently only checks using OF functions (ACPI slave not supported yet).
Signed-off-by: Luis Oliveira <lolivei@synopsys.com>
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When system enters VLLS mode, module power is turned off. As a result,
all registers are reset to HW default value. After exiting VLLS mode,
registers are still in default mode. As a result, the pinctrl settings
are incorrect, which will affect the module function.
The patch recovers the pinctrl setting when exit VLLS mode.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
[wsa: added missing include]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Declare dev_pm_ops structures as const as they are only stored in the pm
field of a device_driver structure. This field is of type const, so
dev_pm_ops structures having similar properties can be declared const
too.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit implements suspend/resume support in the mv64xxx I2C
controller driver. There is no need to implement a ->suspend() hook, as
calling mv64xxx_i2c_hw_init() at ->resume() time is enough.
Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Reviewed-by: Nadav Haklai <nadavh@marvell.com>
Reviewed-by: Lior Amsalem <alior@marvell.com>
Tested-by: Lior Amsalem <alior@marvell.com>
[Thomas: switch to dev_pm_ops, fix build warning when !PM.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds support for the STM32F4 I2C controller.
Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The cadence I2C driver calls cdns_i2c_writereg(..) to setup a workaround
in the controller, but did so after calling i2c_add_adapter() which starts
probing devices on the bus. Change the order so that the configuration is
completely finished before using the adapter.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
On AMD's SB800 and upwards, the SMBus is shared with the Integrated
Micro Controller (IMC).
The platform provides a hardware semaphore to avoid race conditions
among them. (Check page 288 of the SB800-Series Southbridges Register
Reference Guide http://support.amd.com/TechDocs/45482.pdf)
Without this patch, many access to the SMBus end with an invalid
transaction or even with the bus stalled.
Reported-by: Alexandre Desnoyers <alex@qtec.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>:
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Trivial fix to spelling mistake in WARN message, insufficient has
an insufficient number of i's in the spelling.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In of_i2c_register_device(), when the check for
device address validity fails we print the info.addr,
which has not been assigned properly.
Fix this by printing the actual invalid address.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: b4e2f6ac12 ("i2c: apply DT flags when probing")
Cc: stable@kernel.org
Falling back unconditionally to HostNotify as primary client's interrupt
breaks some drivers which alter their functionality depending on whether
interrupt is present or not, so let's introduce a board flag telling I2C
core explicitly if we want wired interrupt or HostNotify-based one:
I2C_CLIENT_HOST_NOTIFY.
For DT-based systems we introduce "host-notify" property that we convert
to I2C_CLIENT_HOST_NOTIFY board flag.
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_smbus_xfer() does not always fill an entire block, allowing
kernel stack memory disclosure through the temp variable. Clear
it before it's read to.
Signed-off-by: Vlad Tsyrklevich <vlad@tsyrklevich.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
smbus functions return -ve on error, 0 on success. However,
__i2c_transfer() have a different return signature - -ve on error, or
number of buffers transferred (which may be zero or greater).
The upshot of this is that the sense of the test is reversed when using
the mux on a bus supporting the master_xfer method: we cache the value
and never retry if we fail to transfer any buffers, but if we succeed,
we clear the cached value.
Fix this by making mlxcpld_mux_reg_write() return a -ve error code for
all failure cases, just as was done in commit 7f638c1cb0 ("i2c: mux:
pca954x: fix i2c mux selection caching").
This also aligns the implementations of these two muxes in this area.
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
ACPI always sets Tx/Rx FIFO to 32. This configuration will
cause problem if the IP core supports a FIFO size of less than 32.
The driver should read the FIFO size from the IP and select the smaller
one of the two.
Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In DTB case, i2c-core doesn't create slave device which is installed
on i2c-xgene bus because of missing code in this driver.
This patch fixes this issue.
Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
smbus functions return -ve on error, 0 on success. However,
__i2c_transfer() have a different return signature - -ve on error, or
number of buffers transferred (which may be zero or greater.)
The upshot of this is that the sense of the test is reversed when using
the mux on a bus supporting the master_xfer method: we cache the value
and never retry if we fail to transfer any buffers, but if we succeed,
we clear the cached value.
Fix this by making pca954x_reg_write() return a negative error code for
all failure cases.
Fixes: 463e8f845c ("i2c: mux: pca954x: retry updating the mux selection on failure")
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Mike Looijmans