[PATCH 2/3] leds/pwm: Don't disable pwm when setting brightness to 0

Thierry Reding thierry.reding at gmail.com
Mon Dec 2 07:33:19 EST 2013


On Mon, Nov 25, 2013 at 09:43:44PM +0100, Uwe Kleine-König wrote:
> This fixes disabling the LED on i.MX28. The PWM hardware delays using
> the newly set pwm-config until the beginning of a new period. It's very
> likely that pwm_disable is called before the current period ends. In
> case the LED was on brightness=max before the LED stays on because in
> the disabled PWM block the period never ends.
> 
> Also only call pwm_enable only once in the probe call back and the
> matching pwm_disable in .remove(). Moreover the pwm is explicitly
> initialized to off.

While I do understand the reasoning behind this, if this is really the
behaviour that we need then there's no use in having pwm_enable() and
pwm_disable() at all. They can just be folded into pwm_get() and
pwm_put(), respectively.

Thierry
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 836 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20131202/5e458ca4/attachment.sig>


More information about the linux-arm-kernel mailing list