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From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
To: linux-leds@vger.kernel.org
Subject: leds-pwm: issue in  __led_pwm_set()
Date: Wed, 25 Sep 2013 22:00:13 +0200	[thread overview]
Message-ID: <524340CD.4060403@free-electrons.com> (raw)

Hi,

I'm using leds-pwm on an atmel sama5d31 based board. I have one
question/issue. In __led_pwm_set(), if the duty cycle is 0,
pwm_disable() is called. This won't work fine on that platform. What
happens is that pwm_config() correctly sets the duty cycle to 0 which is
behaving correctly with that controller (and in my case, putting the
line low). But the call to pwm_disable() is making the pwm controller
release the line and then it is set to high.

I've tried various configurations, like configuring a pull-down on the
pin but I still observe the same behavior. For now, I have a workaround
in atmel-pwm (I activate the output overdrive when duty cycle is 0). But
I believe, we should find another way to do that.

Any input is appreciated.

Regards,

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com


             reply	other threads:[~2013-09-25 20:00 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-25 20:00 Alexandre Belloni [this message]
2013-09-26  0:28 ` leds-pwm: issue in __led_pwm_set() Milo Kim
2013-09-26  7:13   ` Alexandre Belloni
2013-09-26  7:34     ` Milo Kim
2013-09-26  7:48       ` Alexandre Belloni
2013-09-27 15:51         ` Milo Kim
2013-09-27 16:15           ` Alexandre Belloni
2013-09-27 17:23             ` Milo Kim
2013-09-27 17:33               ` Milo Kim
2013-09-27 18:34                 ` Alexandre Belloni
2013-09-27 19:46                   ` Alexandre Belloni
2013-09-28 13:29                     ` Milo Kim

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