[PATCH 1/2] ARM: dts: omap3-overo: Add support for pwm-leds
Florian Vaussard
florian.vaussard at epfl.ch
Thu Jan 24 16:14:37 EST 2013
Hi
>>
>>>> I am working on a patch for pwm-twl-led to defer using a workqueue right now.
>>>
>>> Great!
>>> The only thing I worry about is the latency we are going to get with the
>>> workqueue.
>>>
>>
>> If the latency becomes critical, we can create our own workqueue.
>
> Hrm, when we handled the led via gpio-leds it was also going through the same
> path at the end, via i2c to twl4030.
> I think the fix for this is going to be needed in the pwm core level. Just
> need to look at the gpio code to have similar handling of might_sleep interfaces.
>
You are right. But then the pwm core must provide a way to know if the
pwm access function are callable
from atomic context or not (the gpio framework provides gpio_cansleep()).
This implies a good amount of changes to the pwm framework, and
currently we are the only driver using
non-atomic access.
I will take a closer look to the complexity of this solution tomorrow.
Florian
More information about the linux-arm-kernel
mailing list