On Fri, Feb 6, 2009 at 9:16 PM, Nikolaus Schulz <microsch...@web.de> wrote: > On Fri, Feb 06, 2009 at 08:22:11PM -0500, Alex Deucher wrote: >> On Thu, Feb 5, 2009 at 9:22 PM, Nikolaus Schulz <microsch...@web.de> wrote: >> > On my Thinkpad T42 laptop, the builtin LCD display apparently doesn't >> > support >> > DDC, see: >> > >> > luigi[tmp] sudo get-edid >> > get-edid: get-edid version 1.4.1 >> > >> > Performing real mode VBE call >> > Interrupt 0x10 ax=0x4f00 bx=0x0 cx=0x0 >> > Function supported >> > Call successful >> > >> > VBE version 200 >> > VBE string at 0x11110 "ATI MOBILITY RADEON 7500" >> > >> > VBE/DDC service about to be called >> > Report DDC capabilities >> > >> > Performing real mode VBE call >> > Interrupt 0x10 ax=0x4f15 bx=0x0 cx=0x0 >> > Function supported >> > Call successful >> > >> > Monitor and video card combination does not support DDC1 transfers >> > Monitor and video card combination does not support DDC2 transfers >> > 0 seconds per 128 byte EDID block transfer >> > Screen is not blanked during DDC transfer >> > >> > Reading next EDID block >> > >> > VBE/DDC service about to be called >> > Read EDID >> > >> > Performing real mode VBE call >> > Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0 >> > Function supported >> > Call failed >> > >> > The EDID data should not be trusted as the VBE call failed >> > Error: output block unchanged >> > luigi[tmp]$ sudo ddcprobe >> > vbe: VESA 2.0 detected. >> > oem: ATI MOBILITY RADEON 7500 >> > memory: 32704kb >> > mode: 320x200x32k >> > mode: 320x200x64k >> > mode: 320x200x16m >> > mode: 1600x1200x256 >> > mode: 640x400x256 >> > mode: 640x480x256 >> > mode: 640x480x32k >> > mode: 640x480x64k >> > mode: 640x480x16m >> > mode: 1600x1200x32k >> > mode: 800x600x256 >> > mode: 800x600x32k >> > mode: 800x600x64k >> > mode: 800x600x16m >> > mode: 1600x1200x64k >> > mode: 1024x768x256 >> > mode: 1024x768x32k >> > mode: 1024x768x64k >> > mode: 1024x768x16m >> > mode: 1280x1024x256 >> > mode: 1280x1024x32k >> > mode: 1280x1024x64k >> > mode: 1280x1024x16m >> > edid: >> > edidfail >> > luigi[tmp]$ >> > >> > I have tried get-edid with various controller numbers because, if I read >> > Xorg.0.log correctly, the LVDS doesn't map to controller #0, but to no >> > avail. >> > >> > However, there *is* a valid EDID available from the ACPI BIOS, >> > accessible in /proc/acpi/video/VID/LCD0/EDID, but it is ignored: >> > >> > luigi[tmp]$ hd /proc/acpi/video/VID/LCD0/EDID >> > 00000000 00 ff ff ff ff ff ff 00 24 4d 55 0a 00 00 00 00 >> > |........$MU.....| >> > 00000010 00 0e 01 03 80 1e 17 78 ee ee 91 a3 54 4c 99 26 >> > |.......x....TL.&| >> > 00000020 0f 50 54 21 08 00 01 01 01 01 01 01 01 01 01 01 >> > |.PT!............| >> > 00000030 01 01 01 01 01 01 64 19 00 40 41 00 26 30 18 88 >> > |.........@a.&0..| >> > 00000040 36 00 30 e4 10 00 00 18 00 00 00 fc 00 54 68 69 >> > |6.0..........Thi| >> > 00000050 6e 6b 50 61 64 20 4c 43 44 20 00 00 00 fc 00 31 |nkPad LCD >> > .....1| >> > 00000060 30 32 34 78 37 36 38 0a 20 20 20 20 00 00 00 00 |024x768. >> > ....| >> > 00000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 aa >> > |................| >> > 00000080 >> > luigi[tmp]$ >> > >> > I see no reason why the X server (or the driver, who ever is responsible) >> > shouldn't check the ACPI BIOS if DDC fails, especially as DDC failures >> > seem to >> > be not uncommon with laptop panels. >> > >> > I have worked around my problem by manually feeding the ACPI EDID to >> > parse-edid >> > and copying the result to xorg.conf, see below. xrandr still thinks the >> > display has zero width and height, but xdpyinfo and Xorg.0.log look fine >> > AFAICT. Let me know if you need more information. >> >> The driver is able to to get the panel timings out of the bios lcd >> info table, so even if there is no panel edid, the panel will still >> work properly. I suspect the ACPI edid is generated from the lcd info >> table anyway. > > Hmm, I guess that depends on how you define "properly working". It was > working, yes, but properly? At least it didn't get the display size and > dpi right, but defaulted to standard 96 dpi. Which wasn't a horrible > failure, but still.
You can specify the display size in your config. I'll ask the bios guys if there is a better way of getting the display size info for panels without an edid. Alex -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
