From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: Questions about fbdriver integration Date: Sun, 25 Nov 2007 09:49:31 +0100 (CET) Message-ID: References: <20071124214325.GD3183@pruts.nl> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1IwDBJ-0007T2-TQ for linux-fbdev-devel@lists.sourceforge.net; Sun, 25 Nov 2007 00:49:38 -0800 Received: from hoboe1bl1.telenet-ops.be ([195.130.137.72]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1IwDBI-0007rH-Ap for linux-fbdev-devel@lists.sourceforge.net; Sun, 25 Nov 2007 00:49:37 -0800 Received: from localhost (localhost.localdomain [127.0.0.1]) by hoboe1bl1.telenet-ops.be (Postfix) with SMTP id 3CFA5D4026 for ; Sun, 25 Nov 2007 09:49:32 +0100 (CET) Received: from anakin.of.borg (d54C15D55.access.telenet.be [84.193.93.85]) by hoboe1bl1.telenet-ops.be (Postfix) with ESMTP id 1F3CAD401C for ; Sun, 25 Nov 2007 09:49:32 +0100 (CET) Received: from anakin.of.borg (localhost [127.0.0.1]) by anakin.of.borg (8.14.1/8.14.1/Debian-9) with ESMTP id lAP8nVAo002794 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Sun, 25 Nov 2007 09:49:31 +0100 Received: from localhost (geert@localhost) by anakin.of.borg (8.14.1/8.14.1/Submit) with ESMTP id lAP8nVEg002791 for ; Sun, 25 Nov 2007 09:49:31 +0100 In-Reply-To: <20071124214325.GD3183@pruts.nl> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-fbdev-devel-bounces@lists.sourceforge.net Errors-To: linux-fbdev-devel-bounces@lists.sourceforge.net To: linux-fbdev-devel@lists.sourceforge.net On Sat, 24 Nov 2007, Ico Doornekamp wrote: > I have just finished writing a framebuffer driver for a LCD display > connected to our embedded system (monochrome, 128x64, GPIO driven). > It's very similar to the hecubafb driver, and uses deferred IO. I've > included some of the drivers properties at the end of this mail. Things > works fine when displaying images by doing write()s to /dev/fb0, so this > part seems to be ok. > > I hope some of the regulars on this list can clear up some issues > I've run into when using this driver: > > - My next step as to redirect the linux console to this framebuffer > device. I've configured the kernel for framebuffer console, and when > loading the fbcon module, the message > > Console: switching to mono frame buffer device 16x4" > > appears, and > > cat /sys/class/vtconsole/vtcon1/name -> (M) frame buffer device > cat /sys/class/vtconsole/vtcon1/bind -> 1 > > This seems just fine to me, but however, no output appears on the > display: just a blank screen. > > It seems that the console is doing *something*, since my driver gets > triggered by the deferred IO every 200msec (blinking cursor?), problem > is that the data arriving in my driver is all zeroes! Fbcon writes to the memory at fb_info.screen_base. > - The other question is more a userspace issue: I was hoping to use the > xorg fbdev server on my dislay, but unfortunately this does not seem > to support 1 bit depth displays : > > (EE) FBDEV(0): unsupported number of bits per pixel: 1 > > Is there a way to make X work on 1-bit fb devices, or am I out of luck > here ? The old XF86_FBDev (from XFree86 3.x) definitely works with monochrome. I expect (but never tried) KDrive also to support it. It's a pity many frame buffer organizations were dropped in Xorg. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/