Re: [PATCH] pwm-backlight: add regulator and GPIO support

From: Alex Courbot
Date: Wed Jul 04 2012 - 22:35:50 EST

On 07/05/2012 12:24 AM, Mark Brown wrote:
On Thu, Jul 05, 2012 at 12:14:39AM +0900, Alex Courbot wrote:
On Wed 04 Jul 2012 10:00:56 PM JST, Sascha Hauer wrote:

Also please be aware that using a regulator in the pwm backlight will
instantly break all existing users. That's hardly your fault though.

Sorry, I don't see why. Could you elaborate on this?

All existing machines will start failing during probe as they won't be
able to find the regulator - you should ideally make sure everyone in
mainline gets an appropriate regulator set up.

Oh, that is a mistake of mine then. Driver probe should continue if no regulator is declared (but should fail if some other error occured). I want to maintain backward compatibility with current users of the driver, so regulator/gpio specification should be optional.

Thanks for all the feedback people - I will come back with a new version that addresses the points highlighted and also allows power on/off sequences to be specified in the device tree.

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