• Daniel Drake's avatar
    viafb: don't touch clock state on OLPC XO-1.5 · 012a1211
    Daniel Drake authored
    As detailed in the thread titled "viafb PLL/clock tweaking causes XO-1.5
    instability," enabling or disabling the IGA1/IGA2 clocks causes occasional
    stability problems during suspend/resume cycles on this platform.
    
    This is rather odd, as the documentation suggests that clocks have two
    states (on/off) and the default (stable) configuration is configured to
    enable the clock only when it is needed. However, explicitly enabling *or*
    disabling the clock triggers this system instability, suggesting that there
    is a 3rd state at play here.
    
    Leaving the clock enable/disable registers alone solves this problem.
    This fixes spurious reboots during suspend/resume behaviour introduced by
    commit b692a63a.
    Signed-off-by: default avatarDaniel Drake <dsd@laptop.org>
    Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
    Cc: stable@vger.kernel.org
    012a1211
via_clock.c 9.28 KB