On Thu, 24 Mar 2022, Lee Shawn C shawn.c.lee@intel.com wrote:

From: Cooper Chiou cooper.chiou@intel.com

Tag code stored in bit7:5 for CTA block byte[3] is not the same as CEA extension block definition. Only check CEA block has basic audio support.

v3: update commit message.

Cc: stable@vger.kernel.org Cc: Jani Nikula jani.nikula@intel.com Cc: Shawn C Lee shawn.c.lee@intel.com Cc: intel-gfx intel-gfx@lists.freedesktop.org Signed-off-by: Cooper Chiou cooper.chiou@intel.com Signed-off-by: Lee Shawn C shawn.c.lee@intel.com Fixes: e28ad544f462 ("drm/edid: parse CEA blocks embedded in DisplayID") Reviewed-by: Jani Nikula jani.nikula@intel.com

Thanks for the patch, pushed to drm-misc-next-fixes.

BR, Jani.

---

drivers/gpu/drm/drm_edid.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 561f53831e29..f07af6786cec 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -4859,7 +4859,8 @@ bool drm_detect_monitor_audio(struct edid *edid) if (!edid_ext) goto end;

• has_audio = ((edid_ext[3] & EDID_BASIC_AUDIO) != 0);

• has_audio = (edid_ext[0] == CEA_EXT &&

•     (edid_ext[3] & EDID_BASIC_AUDIO) != 0);
  

if (has_audio) { DRM_DEBUG_KMS("Monitor has basic audio support\n");