kernel/git/stable/linux.git/drivers/pwm, branch linux-5.5.y

pwm: pca9685: Fix PWM/GPIO inter-operation

2020-04-21T07:06:33+00:00

commit 9cc5f232a4b6a0ef6e9b57876d61b88f61bdd7c2 upstream. This driver allows pwms to be requested as gpios via gpiolib. Obviously, it should not be allowed to request a GPIO when its corresponding PWM is already requested (and vice versa). So it requires some exclusion code. Given that the PWMm and GPIO cores are not synchronized with respect to each other, this exclusion code will also require proper synchronization. Such a mechanism was in place, but was inadvertently removed by Uwe's clean-up in commit e926b12c611c ("pwm: Clear chip_data in pwm_put()"). Upon revisiting the synchronization mechanism, we found that theoretically, it could allow two threads to successfully request conflicting PWMs/GPIOs. Replace with a bitmap which tracks PWMs in-use, plus a mutex. As long as PWM and GPIO's respective request/free functions modify the in-use bitmap while holding the mutex, proper synchronization will be guaranteed. Reported-by: YueHaibing Fixes: e926b12c611c ("pwm: Clear chip_data in pwm_put()") Cc: Mika Westerberg Cc: Uwe Kleine-König Cc: YueHaibing Link: https://lkml.org/lkml/2019/5/31/963 Signed-off-by: Sven Van Asbroeck Reviewed-by: Mika Westerberg [cg: Tested on an i.MX6Q board with two NXP PCA9685 chips] Tested-by: Clemens Gruber Reviewed-by: Sven Van Asbroeck # cg's rebase Link: https://lore.kernel.org/lkml/20200330160238.GD2817345@ulmo/ Signed-off-by: Thierry Reding Signed-off-by: Greg Kroah-Hartman

pwm: omap-dmtimer: put_device() after of_find_device_by_node()

2020-03-05T15:45:23+00:00

commit c7cb3a1dd53f63c64fb2b567d0be130b92a44d91 upstream. This was found by coccicheck: drivers/pwm/pwm-omap-dmtimer.c:304:2-8: ERROR: missing put_device; call of_find_device_by_node on line 255, but without a corresponding object release within this function. Reported-by: Markus Elfring Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Greg Kroah-Hartman

pwm: Remove set but not set variable 'pwm'

2020-02-24T07:38:37+00:00

[ Upstream commit 9871abffc81048e20f02e15d6aa4558a44ad53ea ] Fixes gcc '-Wunused-but-set-variable' warning: drivers/pwm/pwm-pca9685.c: In function ‘pca9685_pwm_gpio_free’: drivers/pwm/pwm-pca9685.c:162:21: warning: variable ‘pwm’ set but not used [-Wunused-but-set-variable] It is never used, and so can be removed. In that case, hold and release the lock 'pca->lock' can be removed since nothing will be done between them. Fixes: e926b12c611c ("pwm: Clear chip_data in pwm_put()") Signed-off-by: yu kuai Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional

2020-02-24T07:38:36+00:00

[ Upstream commit 43efdc8f0e6d7088ec61bd55a73bf853f002d043 ] In the old code (e.g.) mutex_destroy() was called before pwmchip_remove(). Between these two calls it is possible that a PWM callback is used which tries to grab the mutex. Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: omap-dmtimer: Simplify error handling

2020-02-24T07:38:06+00:00

[ Upstream commit c4cf7aa57eb83b108d2d9c6c37c143388fee2a4d ] Instead of doing error handling in the middle of ->probe(), move error handling and freeing the reference to timer to the end. This fixes a resource leak as dm_timer wasn't freed when allocating *omap failed. Implementation note: The put: label was never reached without a goto and ret being unequal to 0, so the removed return statement is fine. Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

Merge tag 'pwm/for-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

2019-12-05T19:28:14+00:00

Pull pwm updates from Thierry Reding: "Various changes and minor fixes across a couple of drivers" * tag 'pwm/for-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: pwm: stm32: Pass breakinput instead of its values pwm: stm32: Remove clutter from ternary operator pwm: stm32: Validate breakinput data from DT pwm: Update comment on struct pwm_ops::apply pwm: sun4i: Fix incorrect calculation of duty_cycle/period pwm: stm32: Add power management support pwm: stm32: Split breakinput apply routine to ease PM support dt-bindings: pwm-stm32: Document pinctrl sleep state pwm: sun4i: Drop redundant assignment to variable pval dt-bindings: pwm: mediatek: Remove gratuitous compatible string for MT7629

Merge 5.4-rc7 into staging-next

2019-11-11T05:23:37+00:00

We want the staging fixes in here, and it resolves some merge issues. Signed-off-by: Greg Kroah-Hartman

pwm: bcm-iproc: Prevent unloading the driver module while in use

2019-11-08T17:38:06+00:00

The owner member of struct pwm_ops must be set to THIS_MODULE to increase the reference count of the module such that the module cannot be removed while its code is in use. Fixes: daa5abc41c80 ("pwm: Add support for Broadcom iProc PWM controller") Signed-off-by: Uwe Kleine-König Reviewed-by: Florian Fainelli Signed-off-by: Thierry Reding

pwm: stm32: Pass breakinput instead of its values

2019-10-21T14:50:05+00:00

Instead of passing the individual values of the breakpoint, pass a pointer to the breakpoint. Signed-off-by: Thierry Reding

pwm: stm32: Remove clutter from ternary operator

2019-10-21T14:50:05+00:00

Remove usage of the ternary operator to assign values for register fields. Instead, parameterize the register and field offset macros and pass the index to them. This removes clutter and improves readability. Signed-off-by: Thierry Reding