lkml.org 
[lkml]   [2001]   [Aug]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] make psaux reconnect adjustable
    Andries.Brouwer@cwi.nl wrote:
    >
    > From garloff@garloff.de Tue Aug 14 11:57:23 2001
    >
    > I can confirm what you suggest:
    > My mouse (Logitech wheel USB/PS2) sends indeed AA 00.
    > So, I extended my patch:
    > psmouse_reconnect = 0: Do nothing (just pass all to userspace)
    > psmouse_reconnect = 1: Flush Q & ping mouse on AA 00 (default)
    > psmouse_reconnect = 2: Flush Q & ping mouse on AA (old behaviour)
    >
    > With reconnect 1 or 2: After reconnecting, mouse behaves strange
    > (jumping around the screen)

    This is a serious bug in many user-space drivers. PS/2 mouse protocol
    was designed to easily re-synchronize (think about transmission errors/
    lost bytes).

    > With reconnect 0: Mouse is dead

    This is a bug in all user-space drivers (understandable as the
    kernel tried to be too clever). They must send the proper ps2-enabling
    sequence after they see "aa 00".

    >
    > In both cases restarting gpm gets the mouse back to work again.
    > It seems the imps2 driver does some initialization to the mouse.
    >
    > If I use the plain ps2 driver, then finally, I see the benefit of the
    > reconnect code in the kernel:
    > With reconnect = 1 or 2: It works after replugging
    > With reconnect = 0: Mouse is dead after replugging
    >
    > In the latter case restarting gpm helps.
    ...

    Add an "ioctl(PS2_TRANSPARENT)", to disable the current kernel policy.
    So new drivers which understand about "aa 00" sequences can act properly.
    Don't break existing apps.
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 12:57    [W:0.039 / U:31.940 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site