On Fri, 2006-12-29 at 13:04 +0000, Robert de Bath wrote: > > That's bug #338241. I'm pondering changing the fbdev driver to default > > to 32bpp though. > Well I suppose 32bpp is more likely with modern hardware.
FWIW, xf86-video-fbdev 0.3.1 defaults to 32. > Still even if you can't easily get fb_var_screeninfo.bits_per_pixel as > your default a big fat warning that they don't match and how to fix it > would be in order IMO. I don't know any way to determine that's the specific reason for the FBIOPUT_VSCREENINFO ioctl failing. If there are any framebuffer devices that accept 24 bpp but not 32 bpp, I guess the fbdev driver could check for that, but I don't particularly feel like spending more time on this right now. > > I noticed that, but it's more likely a bug in vesafb. As the log > > indicates, the fbdev driver actually queries the framebuffer device on > > the usability of each mode. > > I've had a look at the kernel code ... > Well it seems that the vesafb doesn't have an fb_check_var function to > call so the FBIOPUT_VSCREENINFO ioctl is defined by fbmem.c to be the > same as FBIOGET_VSCREENINFO. > > This is actually reasonable, it's trying to tell you the closest mode > to the one you asked for. But X will have to check that the mode it gets > back is "the same" as the one it asked for and reject it if not. > (Especially if the returned mode is SMALLER than the request!) X considers modes to be different even if only a single parameter differs, so I've changed fbdevhw to report failure in that case in http://gitweb.freedesktop.org/?p=xorg/xserver.git;a=commitdiff;h=f6815cb68b0f6698497348fc6e4214dacef33b95 > Also the TEST function doesn't look like it's implemented properly in > all the drivers; I'd make sure you 'GET' the original setup and 'TEST' > it after you've tested all your configured modes! I don't understand what you're saying here, please elaborate. > > ... > > But back to the beginning; the bug this report was opened for looks fixed > to me. Yes, so please follow up to the linux-fbdev-devel list (or another appropriate place) only. -- Earthling Michel Dänzer | http://tungstengraphics.com Libre software enthusiast | Debian, X and DRI developer