From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Antonino A. Daplas" Subject: Re: FB_EVENT (blank and unblank?) Date: Sun, 28 Nov 2004 08:24:00 +0800 Message-ID: <200411280824.01338.adaplas@hotpop.com> References: <41A36DA5.8090200@fujitsu-siemens.com> <200411280643.14171.adaplas@hotpop.com> <027d01c4d4dd$19fe65a0$0f01a8c0@max> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1CYCrx-0004md-Ic for linux-fbdev-devel@lists.sourceforge.net; Sat, 27 Nov 2004 16:24:49 -0800 Received: from smtp-out.hotpop.com ([38.113.3.61]) by sc8-sf-mx1.sourceforge.net with esmtp (Exim 4.41) id 1CYCrp-00028q-Kj for linux-fbdev-devel@lists.sourceforge.net; Sat, 27 Nov 2004 16:24:49 -0800 Received: from hotpop.com (kubrick.hotpop.com [38.113.3.103]) by smtp-out.hotpop.com (Postfix) with SMTP id 142B7A98769 for ; Sun, 28 Nov 2004 00:24:34 +0000 (UTC) In-Reply-To: <027d01c4d4dd$19fe65a0$0f01a8c0@max> Content-Disposition: inline Sender: linux-fbdev-devel-admin@lists.sourceforge.net Errors-To: linux-fbdev-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: List-Post: List-Help: List-Subscribe: , List-Archive: Content-Type: text/plain; charset="us-ascii" To: Richard Purdie , adaplas@pol.net, linux-fbdev-devel@lists.sourceforge.net On Sunday 28 November 2004 07:59, Richard Purdie wrote: > Antonino A. Daplas: > > On Saturday 27 November 2004 22:53, Richard Purdie wrote: > >> I have two places where they need to talk. The first is for the touch > >> screen to query the x resolution (and to know if the screen is > >> blanked)[1]. > >> The second is to turn the backlight off when the console is blanked. > > > > Can you adopt the backlight support infrastructure in powermacs? See > > arch/ppc/platforms/pmac_backlight.c Currently, it's PPC-specific, but it > > can be extended to other platforms. A few drivers use this, rivafb is > > one of > > them (drivers/video/fbdev.c), and aty. > > There are two issues here and this addresses the wrong one. > > My Issue: I have a backlight driver that shares no code with the > framebuffer driver - the hardware is totally separate. I have there written > them as two spate drivers which seems to make sense. The problem is that > there is no method to communicate blanking to the external backlight driver > (which is all it needs to know about). Obviously I can add links between Of course there is. Your backlight driver does a register_backlight_controllers(). Then your fb driver does a set_backlight_enable(!blank) in its xxxfb_blank implementation. > them but I feel that's ugly. Adding a couple of extra events to the > fb_register_client system would be much neater. > > The Other Issue: There is no common method to access and control backlight Not yet, but if the powermac backlight support is extended, then we suddenly have a common method. Right now, pmac's backlight support has this as exportable symbols: set_backlight_enable() get_backlight_enable() set_backlight_level() get_backlight_level() And all of the above calls specific hooks to the backlight driver. > levels within the kernel. My feeling on this is that they should appear in > sysfs as their own class. I need to look into this as I know there has been > discussion in the past and I don't know what the issues are. I'd welcome > any comments on this though. We don't have a common architecture yet for backlight control, and I don't know where this is really going. Anyone here have more info? Tony ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/