[PATCH v3 0/3] leds-pwm: Defer PWM calls if PWM can sleep
florian.vaussard at epfl.ch
Mon Jan 28 09:00:56 EST 2013
When using the leds-pwm module with external PWM chips connected through
I2C, the kernel will panic when settings a trigger. In this case, PWM
calls can sleep, and should be deferred.
Patch 1 and 2 add the necessary API to the PWM subsystem, and update
matching drivers. Patch 3 updates leds-pwm to use a worker if the PWM
chip can sleep, or performs direct calls otherwise.
This patchset is based on the for-next branch of the led subsystem ,
as patch 3 depends on the recent work of Peter for DT bindings in leds-pwm.
The pwm patches should probably follow the same path.
Tested on Overo (OMAP3 + TWL4030) with device tree.
Changes from v2:
* pwm_cansleep -> pwm_can_sleep
* use bool for can_sleep member
* minor fixes
Changes from v1:
* pwm_can_sleep -> pwm_cansleep
* avoid duplicated code between the worker and the direct call
* cache the value of pwm_cansleep inside leds-pwm to avoid API calls
Florian Vaussard (3):
pwm: Add pwm_can_sleep() as exported API to users
pwm: Add can_sleep property to drivers
leds: leds-pwm: Defer led_pwm_set() if PWM can sleep
drivers/leds/leds-pwm.c | 50 +++++++++++++++++++++++++++++++++++++-------
drivers/pwm/core.c | 12 ++++++++++
drivers/pwm/pwm-twl-led.c | 1 +
drivers/pwm/pwm-twl.c | 1 +
include/linux/pwm.h | 10 +++++++++
5 files changed, 66 insertions(+), 8 deletions(-)
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