From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
To: Milo Kim <milo.kim@ti.com>
Cc: linux-leds@vger.kernel.org, Thierry Reding <thierry.reding@gmail.com>
Subject: Re: leds-pwm: issue in __led_pwm_set()
Date: Thu, 26 Sep 2013 09:48:29 +0200 [thread overview]
Message-ID: <5243E6CD.4070402@free-electrons.com> (raw)
In-Reply-To: <5243E38C.4090006@ti.com>
On 26/09/2013 09:34, Milo Kim wrote:
>
> Ah, I didn't mean the pinctrl subsystem. Sorry for confusing you.
>
> I just want to know the reason why 'atmel_pwm_disable()' releases the
> PWM pin.
> I can't find it in the driver. Am I missing something?
>
Hum, maybe my wording was wrong. What I meant is that when that
disabling the PWM channel by using the PWM_DIS
register, the PWM is not driving the pin anymore. Then, the level goes
from low (which is correct) to high. Also, the datasheet specifies that
the pwm has to be enabled to get the correct level when duty == 0 or
duty == period.
IIRC, this is not the same on TI SoC where duty == 0 don't give you the
expected behavior and I can understand why there is a pwm_disable()
there. Maybe we have to have a way to differentiate both cases ?
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
next prev parent reply other threads:[~2013-09-26 7:48 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-25 20:00 leds-pwm: issue in __led_pwm_set() Alexandre Belloni
2013-09-26 0:28 ` Milo Kim
2013-09-26 7:13 ` Alexandre Belloni
2013-09-26 7:34 ` Milo Kim
2013-09-26 7:48 ` Alexandre Belloni [this message]
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
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5243E6CD.4070402@free-electrons.com \
--to=alexandre.belloni@free-electrons.com \
--cc=linux-leds@vger.kernel.org \
--cc=milo.kim@ti.com \
--cc=thierry.reding@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.