[lkml]   [2009]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH] olpc: fix model detection without OFW

    * Andres Salomon <> wrote:

    > On Sat, 14 Feb 2009 22:43:12 +0100
    > Ingo Molnar <> wrote:
    > [...]
    > >
    > > Applied to tip:x86/urgent [for v2.6.29], thanks guys!
    > >
    > > Did i get the impact-line below right?
    > >
    > > Ingo
    > >
    > More like -
    > Impact: garbled display, laptop is unusable
    > ;)

    ah, okay :-) Serious regression that warrants urgent upstream routing.

    > The DCON detection code determines whether there's a DCON attached
    > based upon the model (any XO model >= B2 is assumed to have a DCON).
    > The LXFB driver determines which mode to use based upon whether or not
    > it thinks there's a DCON attached, and the DCON/LXFB can't deal w/
    > standard modes.
    > So, the result is that LXFB attempts to use some random standard mode
    > rather than the DCON-required 1200x900, and the display is unusable.

    Where did my git grepping skills go wrong?

    I git-grepped the code and this is the scope i found:

    olpc_platform_info.boardrev is used for:

    - a printk
    - olpc_board_at_least() which is used in:
    - drivers/input/mouse/hgpk.c: mouse driver quirk
    - sound/pci/cs5535audio/cs5535audio_olpc.c: audio quirk

    aha. I missed this roundabout impact:

    - arch/x86/kernel/olpc.c: OLPC_F_DCON flag
    - which is used in olpc_has_dcon(), which is used in:
    - drivers/video/geode/gxfb_core.c: GX modes db
    [ouch if this goes wrong!]
    - drivers/video/geode/lxfb_core.c: ditto

    So i guess the mouse and audio quirk point was correct too, but the
    major impact is the graphics mode array mismatch and the resulting
    nonsensical mode setting, right?


     \ /
      Last update: 2009-02-14 23:17    [W:0.025 / U:0.036 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site