From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by canuck.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1RCAGf-0007nD-MU for barebox@lists.infradead.org; Fri, 07 Oct 2011 13:15:18 +0000 Date: Fri, 7 Oct 2011 15:15:08 +0200 From: Sascha Hauer Message-ID: <20111007131508.GD31404@pengutronix.de> References: <4E8D6133.8080604@free-electrons.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4E8D6133.8080604@free-electrons.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [RFC/PATCH 0/2] Backlight support To: Gregory CLEMENT Cc: barebox Hi Gregory, On Thu, Oct 06, 2011 at 10:05:07AM +0200, Gregory CLEMENT wrote: > This patch set is a RFC about a backlight framework. The purpose of > this framework is mainly to allow to add easily a support for a > backlight with the possibility of setting brightness directly from the > barebox shell using the brightness parameter. > > An implementation is provided for i.MX23 by using the PWM. It was > tested on a custom i.MX23 base board. Two things that bother me in this series. First thing is that I wonder if it would be better to not register a seperate device for backlight. How about a call like this: fb_register_backlight(const char *fb, void (*set_brightness)(int brightness, void *priv)); The core would only need a function to find the struct device_d by the corresponding "fbx" string. This way we could add the brightness variable to the framebuffer and not a seperate device, so fb0.brightness=50. The second thing is that the pwm you use for the mxs backlight is a generic pwm which not necessarily drives a backlight. We should have a generic pwm api for this. Otherwise we end up with different drivers for the same pwm. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox