• Tomi Valkeinen's avatar
    OMAPDSS: apply fixes · 7a53df2c
    Tomi Valkeinen authored
    When omapfb does ovl->get_overlay_info, ovl->set_overlay_info, the set
    function may fail even if the info has not been changed. This is because
    omapdss doesn't initialize the info, but expect the caller to set valid
    values.
    
    Normally that is the case, but there is at least one corner case: if
    omapfb has not allocated memory for the overlay yet, and the user uses
    ioctl to disable the overlay to make sure it's disabled. In this case
    get_overlay_info returns invalid data, but the user is only interested
    in setting the overlay to disabled, not configuring it, and
    set_overlay_info fails.
    
    The issue is made possible by the omapfb's setup_plane ioctl, which
    groups overlay configuration and overlay enable/disable bit into the
    same struct. Thus, when you are disabling an overlay, you are also
    configuring it.
    
    This is a bit counter intuitive, so I think it's better to initialize
    the info to some valid values.
    
    The fields requiring initialization are color_mode and rotation_type,
    and also we need to remove the check for (paddr == 0), as paddr is 0 for
    unallocated overlay (but it's still fine to disable the overlay).
    Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
    7a53df2c
overlay.c 4.62 KB