From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH 2/3] pxafb: allow pxafb_set_par() to start from arbitrary yoffset Date: Wed, 17 Dec 2008 20:31:03 +0000 Message-ID: <20081217203103.GD5864@flint.arm.linux.org.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.arm.linux.org.uk Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org+linux-arm-kernel=m.gmane.org@lists.arm.linux.org.uk To: Eric Miao Cc: ARM Linux , linux-fbdev-devel@lists.sourceforge.net On Wed, Dec 17, 2008 at 04:59:00PM +0800, Eric Miao wrote: > @@ -345,10 +343,9 @@ static int pxafb_check_var(struct > fb_var_screeninfo *var, struct fb_info *info) > return -EINVAL; > } > > - var->xres_virtual = > - max(var->xres_virtual, var->xres); > - var->yres_virtual = > - max(var->yres_virtual, var->yres); > + var->xres_virtual = var->xres; > + var->yres_virtual = fbi->fb.fix.smem_len / > + (var->xres * var->bits_per_pixel / 8); Previous experience of doing this with the X server and acornfb is that it causes all sorts of problems - it seems to force the X server into assuming that the framebuffer should be panned no matter what settings you ask it for. The recommended workaround (implemented in acornfb) is to only do these kinds of adjustments if text mode acceleration is enabled. IIRC, the X server should be disabling text mode acceleration when it maps the framebuffer. I seem to remember that there are X servers which forget to do that though. ------------------------------------------------------------------- List admin: http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm-kernel FAQ: http://www.arm.linux.org.uk/mailinglists/faq.php Etiquette: http://www.arm.linux.org.uk/mailinglists/etiquette.php