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path: root/drivers/pwm
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2021-09-02pwm: jz4740: Simplify using devm_pwmchip_add()Uwe Kleine-König1-11/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: iqs620a: Simplify using devm_pwmchip_add()Uwe Kleine-König1-15/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: intel-lgm: Simplify using devm_pwmchip_add()Uwe Kleine-König1-11/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: imx27: Simplify using devm_pwmchip_add()Uwe Kleine-König1-13/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: fsl-ftm: Simplify using devm_pwmchip_add()Uwe Kleine-König1-9/+1
This allows to drop the platform_driver's remove function. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: ep93xx: Simplify using devm_pwmchip_add()Uwe Kleine-König1-10/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: bcm-kona: Simplify using devm_pwmchip_add()Uwe Kleine-König1-11/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: ab8500: Simplify using devm_pwmchip_add()Uwe Kleine-König1-17/+1
This allows to drop the platform_driver's remove function. This is the only user of driver data so this can go away, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: keembay: Improve compile coverage by allowing to enable on !ARM64Uwe Kleine-König1-1/+2
There are no arm64 specific constructs in this driver and it compiles just fine with ARCH=arm. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: jz4740: Improve compile coverage by allowing to enable on !MIPSUwe Kleine-König1-1/+1
There are no mips specific constructs in this driver and it compiles just fine with ARCH=arm. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: ntxec: Drop useless assignment to struct pwmchip::baseUwe Kleine-König1-1/+0
Since commit f9a8ee8c8bcd ("pwm: Always allocate PWM chip base ID dynamically") there is no effect any more for assigning this variable. When the patch resulting in f9a8ee8c8bcd was created, this driver didn't exist yet, so this was missed. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: tiehrpwm: Unprepare clock only after the PWM was unregisteredUwe Kleine-König1-1/+3
The driver is supposed to stay functional until pwmchip_remove() returns. So disable clocks only after that. pwmchip_remove() always returns 0, so the return code can be ignored which keeps ehrpwm_pwm_remove() a bit simpler and eventually allows to make pwmchip_remove() return void. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: rockchip: Unprepare clocks only after the PWM was unregisteredUwe Kleine-König1-1/+3
The driver is supposed to stay functional until pwmchip_remove() returns. So disable clocks only after that. pwmchip_remove() always returns 0, so the return code can be ignored which keeps rockchip_pwm_remove() a bit simpler and allows to eventually make pwmchip_remove() return void. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: hibvt: Disable the clock only after the PWM was unregisteredUwe Kleine-König1-1/+3
The driver is supposed to stay functional until pwmchip_remove() returns. So disable clocks and reset the hardware only after that. The return value of pwmchip_remove doesn't need to be checked because it returns zero anyhow and should be changed to return void eventually. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: stm32-lp: Don't modify HW state in .remove() callbackUwe Kleine-König1-2/+0
A consumer is expected to disable a PWM before calling pwm_put(). And if they didn't there is hopefully a good reason (or the consumer needs fixing). Also if disabling an enabled PWM was the right thing to do, this should better be done in the framework instead of in each low level driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: rockchip: Don't modify HW state in .remove() callbackUwe Kleine-König1-14/+0
A consumer is expected to disable a PWM before calling pwm_put(). And if they didn't there is hopefully a good reason (or the consumer needs fixing). Also if disabling an enabled PWM was the right thing to do, this should better be done in the framework instead of in each low level driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: img: Don't modify HW state in .remove() callbackUwe Kleine-König1-16/+0
A consumer is expected to disable a PWM before calling pwm_put(). And if they didn't there is hopefully a good reason (or the consumer needs fixing). Also if disabling an enabled PWM was the right thing to do, this should better be done in the framework instead of in each low level driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: mxs: Don't modify HW state in .probe() after the PWM chip was registeredUwe Kleine-König1-8/+5
This fixes a race condition: After pwmchip_add() is called there might already be a consumer and then modifying the hardware behind the consumer's back is bad. So reset before calling pwmchip_add(). Note that reseting the hardware isn't the right thing to do if the PWM is already running as it might e.g. disable (or even enable) a backlight that is supposed to be on (or off). Fixes: 4dce82c1e840 ("pwm: add pwm-mxs support") Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: lpc32xx: Don't modify HW state in .probe() after the PWM chip was ↵Uwe Kleine-König1-5/+5
registered This fixes a race condition: After pwmchip_add() is called there might already be a consumer and then modifying the hardware behind the consumer's back is bad. So set the default before. (Side-note: I don't know what this register setting actually does, if this modifies the polarity there is an inconsistency because the inversed polarity isn't considered if the PWM is already running during .probe().) Fixes: acfd92fdfb93 ("pwm: lpc32xx: Set PWM_PIN_LEVEL bit to default value") Cc: Sylvain Lemieux <slemieux@tycoint.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: ab8500: Fix register offset calculation to not depend on probe orderUwe Kleine-König1-3/+14
The assumption that lead to commit 5e5da1e9fbee ("pwm: ab8500: Explicitly allocate pwm chip base dynamically") was wrong: The pwm-ab8500 devices are not directly instantiated from device tree, but from the ab8500 mfd driver. So the pdev->id isn't -1, but a number between 1 and 3. Now that pwmchip ids are always allocated dynamically, this cannot easily be reverted. Introduce a new member in the driver data struct that tracks the hardware id and use this to calculate the register offset. Side-note: Using chip->base to calculate the offset was never robust because if there was already a PWM with id 1 at the time ab8500-pwm.1 was probed, the associated pwmchip would get assigned chip->base = 2 (or something bigger). Fixes: 5e5da1e9fbee ("pwm: ab8500: Explicitly allocate pwm chip base dynamically") Fixes: 6173f8f4ed9c ("pwm: Move AB8500 PWM driver to PWM framework") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-09-02pwm: atmel: Rework tracking updates pending in hardwareUwe Kleine-König1-23/+79
This improves the driver's behavior in several ways: - The lock is held for shorter periods and so a channel that is currently waited for doesn't block disabling another channel. - It's easier to understand because the procedure is split into more semantic units and documentation is improved - A channel is only set to pending when such an event is actually scheduled in hardware (by writing the CUPD register). - Also wait in .get_state() to report the last configured state instead of (maybe) the previous one. This fixes the read back duty cycle and so prevents a warning being emitted when PWM_DEBUG is on. Tested on an AriettaG25. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-07-08pwm: ep93xx: Ensure configuring period and duty_cycle isn't wrongly skippedUwe Kleine-König1-45/+40
As the last call to ep93xx_pwm_apply() might have exited early if state->enabled was false, the values for period and duty_cycle stored in pwm->state might not have been written to hardware and it must be ensured that they are configured before enabling the PWM. Fixes: 6d45374af539 ("pwm: ep93xx: Implement .apply callback") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-07-08pwm: berlin: Ensure configuring period and duty_cycle isn't wrongly skippedUwe Kleine-König1-6/+3
As the last call to berlin_pwm_apply() might have exited early if state->enabled was false, the values for period and duty_cycle stored in pwm->state might not have been written to hardware and it must be ensured that they are configured before enabling the PWM. Fixes: 30dffb42fcd4 ("pwm: berlin: Implement .apply() callback") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-07-08pwm: tiecap: Ensure configuring period and duty_cycle isn't wrongly skippedUwe Kleine-König1-9/+6
As the last call to ecap_pwm_apply() might have exited early if state->enabled was false, the values for period and duty_cycle stored in pwm->state might not have been written to hardware and it must be ensured that they are configured before enabling the PWM. Fixes: 0ca7acd84766 ("pwm: tiecap: Implement .apply() callback") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-07-08pwm: spear: Ensure configuring period and duty_cycle isn't wrongly skippedUwe Kleine-König1-6/+3
As the last call to spear_pwm_apply() might have exited early if state->enabled was false, the values for period and duty_cycle stored in pwm->state might not have been written to hardware and it must be ensured that they are configured before enabling the PWM. Fixes: 98761ce4b91b ("pwm: spear: Implement .apply() callback") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-07-08pwm: sprd: Ensure configuring period and duty_cycle isn't wrongly skippedUwe Kleine-König1-7/+4
As the last call to sprd_pwm_apply() might have exited early if state->enabled was false, the values for period and duty_cycle stored in pwm->state might not have been written to hardware and it must be ensured that they are configured before enabling the PWM. Fixes: 8aae4b02e8a6 ("pwm: sprd: Add Spreadtrum PWM support") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-07-07pwm: Remove redundant assignment to pointer pwmColin Ian King1-1/+1
The pointer pwm is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: ep93xx: Fix read of uninitialized variable retColin Ian King1-0/+1
There is a potential path in function ep93xx_pwm_apply where ret is never assigned a value and it is checked for an error code. Fix this by ensuring ret is zero'd in the success path to avoid this issue. Addresses-Coverity: ("Uninitialized scalar variable") Fixes: f6ef94edf0f6 ("pwm: ep93xx: Unfold legacy callbacks into ep93xx_pwm_apply()") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: ep93xx: Prepare clock before using itAlexander Sverdlin1-7/+7
Use clk_prepare_enable()/clk_disable_unprepare() in preparation for switch to Common Clock Framework. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: ep93xx: Unfold legacy callbacks into ep93xx_pwm_apply()Uwe Kleine-König1-106/+71
This just puts the implementation of ep93xx_pwm_disable(), ep93xx_pwm_enable() and ep93xx_pwm_config() into their only caller. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: ep93xx: Implement .apply callbackUwe Kleine-König1-4/+39
To ease review this reuses the formerly implemented callbacks. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: vt8500: Only unprepare the clock after the pwmchip was removedUwe Kleine-König1-1/+2
Until pwmchip_remove() returns the PWM is supposed to work, so pwmchip_remove() must be called before the clock is stopped. The return value of pwmchip_remove doesn't need to be checked because it returns zero anyhow and I plan to make it return void soon. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: vt8500: Drop if with an always false conditionUwe Kleine-König1-4/+1
vt8500_pwm_remove() is only called after vt8500_pwm_probe() returned successfully. In this case driver data was set to a non-NULL value and so chip can never be NULL. While touching this code also put declaration and assignment in a single line. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: tegra: Assert reset only after the PWM was unregisteredUwe Kleine-König1-1/+3
The driver is supposed to stay functional until pwmchip_remove() returns. So the reset must be asserted only after that. pwmchip_remove() always returns 0, so the return code can be ignored which keeps the tegra_pwm_remove() a bit simpler. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: tegra: Don't needlessly enable and disable the clock in .remove()Uwe Kleine-König1-6/+0
There is no reason to enable the PWM clock just to assert the reset control. (If the reset control depends on the clock this is a bug and probably it doesn't because in .probe() the reset is deasserted without the clock being enabled.) Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: tegra: Don't modify HW state in .remove callbackUwe Kleine-König1-13/+0
A consumer is expected to disable a PWM before calling pwm_put(). And if they didn't there is hopefully a good reason (or the consumer needs fixing). Also if disabling an enabled PWM was the right thing to do, this should better be done in the framework instead of in each low level driver. So drop the hardware modification from the .remove() callback. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: tegra: Drop an if block with an always false conditionUwe Kleine-König1-3/+0
tegra_pwm_remove() is only called after tegra_pwm_probe() successfully completed. In this case platform_set_drvdata() was called with a non-NULL value and so platform_get_drvdata(pdev) cannot return NULL. Returning an error code from a platform_driver's remove function is ignored anyway, so it's a good thing this exit path is gone. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: core: Simplify some devm_*pwm*() functionsAndy Shevchenko1-35/+25
Use devm_add_action_or_reset() instead of devres_alloc() and devres_add(), which works the same. This will simplify the code. There is no functional changes. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: core: Remove unused devm_pwm_put()Andy Shevchenko1-25/+0
There are no users and seems no will come of the devm_pwm_put(). Remove the function. While at it, slightly update documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: core: Unify fwnode checks in the moduleAndy Shevchenko1-6/+7
Historically we have two different approaches on how to check type of fwnode. Unify them using the latest and greatest fwnode related APIs. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: core: Reuse fwnode_to_pwmchip() in ACPI caseAndy Shevchenko1-30/+1
In ACPI case we may use matching by fwnode as provided via fwnode_to_pwmchip(). This makes device_to_pwmchip() not needed anymore. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: core: Convert to use fwnode for matchingAndy Shevchenko1-3/+3
When we traverse the list of the registered PWM controllers, use fwnode to match. This will help for further cleanup. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: sprd: Don't check the return code of pwmchip_remove()Uwe Kleine-König1-1/+3
pwmchip_remove() returns always 0. Don't use the value to make it possible to eventually change the function to return void. This is a good thing as pwmchip_remove() is usually called from a remove function (mostly for platform devices) and their return value is ignored by the device core anyhow. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: img: Fix PM reference leak in img_pwm_enable()Zou Wei1-1/+1
pm_runtime_get_sync will increment pm usage counter even it failed. Forgetting to putting operation will result in reference leak here. Fix it by replacing it with pm_runtime_resume_and_get to keep usage counter balanced. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: pxa: Always use the same variable name for driver dataUwe Kleine-König1-19/+19
In most functions the driver data variable is called pc. Do the same in the two remaining functions. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: pxa: Drop if with an always false conditionUwe Kleine-König1-2/+0
The .remove() function is only called after .probe() returned successfully. In this case platform_set_drvdata() was called with a non-NULL argument and so platfrom_get_drvdata() returns the same non-NULL value. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: berlin: Don't check the return code of pwmchip_remove()Uwe Kleine-König1-3/+3
pwmchip_remove() always returns 0. Don't use the value to make it possible to eventually change the function to return void. This is a good thing as pwmchip_remove() is usually called from a remove function (mostly for platform devices) and their return value is ignored by the device core anyhow. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: berlin: Implement .apply() callbackUwe Kleine-König1-5/+38
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushes down a slightly optimized variant of how legacy drivers are handled in the core. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: berlin: use consistent naming for variablesUwe Kleine-König1-58/+58
A struct berlin_pwm_chip * is now always called "bpc" (instead of "pwm" which is usually used for struct pwm_device * or "chip" which is usually used for struct pwm_chip *). The struct pwm_device * variables were named "pwm_dev" or "pwm"; they are now always called "pwm". Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-28pwm: tiecap: Implement .apply() callbackUwe Kleine-König1-10/+45
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). This just pushes down a slightly optimized variant of how legacy drivers are handled in the core. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>