• Takashi Iwai's avatar
    drm/i915: Enable VLV audio chicken bit for LPE audio · 9db13e5f
    Takashi Iwai authored
    The audio chicken bit (register offset 0x62f38) seems required to make
    DP audio working on some machines.  At least, on Dell Wyse 3040, I
    failed to get the audio unless this bit is set once.
    
    Strangely, the bit seems necessary only once, and it persists after
    that, even some power-off cycles.  The register is supposedly
    write-only, so it's no evidence whether the bit keeps effect
    persistently.  But, judging from the experiment, it looks enough to
    set it up once at the device initialization.
    
    The patch is basically a cut from the original patch by Pierre-Louis
    Bossart.
    
    v1->v2: drop read since it's a write-only reg.
    
    Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
    Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
    Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
    9db13e5f
intel_lpe_audio.c 10.6 KB