On Tue, Feb 22, 2022 at 02:38:17PM +0800, Lee Shawn C wrote:
> Try to find and parse more CEA ext blocks if edid->extensions
> is greater than one.
>
> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx>
> Cc: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
> Signed-off-by: Lee Shawn C <shawn.c.lee@xxxxxxxxx>
> ---
> drivers/gpu/drm/drm_edid.c | 75 +++++++++++++++++++++++---------------
> 1 file changed, 45 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index 12893e7be89b..3d5dbbeca7f9 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -4313,43 +4313,58 @@ add_cea_modes(struct drm_connector *connector, struct edid *edid)
> const u8 *cea = drm_find_cea_extension(edid);
> const u8 *db, *hdmi = NULL, *video = NULL;
> u8 dbl, hdmi_len, video_len = 0;
> - int modes = 0;
> + int modes = 0, j;
>
> - if (cea && cea_revision(cea) >= 3) {
> - int i, start, end;
> + if (!cea)
> + return 0;
>
> - if (cea_db_offsets(cea, &start, &end))
> - return 0;
> + for (j = (cea - (u8 *)edid) / EDID_LENGTH; j <= edid->extensions;) {
That looks rather illegible. I think we want a
drm_find_cea_extension(const struct edid *edid, int *ext_index)
and then just loop until it stops giving us stuff.
There are also several other callers of drm_find_cea_extension().
Why don't they require the same treatment?
> + if (cea && cea_revision(cea) >= 3) {
> + int i, start, end;
>
> - for_each_cea_db(cea, i, start, end) {
> - db = &cea[i];
> - dbl = cea_db_payload_len(db);
> + if (cea_db_offsets(cea, &start, &end))
> + continue;
>
> - if (cea_db_tag(db) == VIDEO_BLOCK) {
> - video = db + 1;
> - video_len = dbl;
> - modes += do_cea_modes(connector, video, dbl);
> - } else if (cea_db_is_hdmi_vsdb(db)) {
> - hdmi = db;
> - hdmi_len = dbl;
> - } else if (cea_db_is_y420vdb(db)) {
> - const u8 *vdb420 = &db[2];
> -
> - /* Add 4:2:0(only) modes present in EDID */
> - modes += do_y420vdb_modes(connector,
> - vdb420,
> - dbl - 1);
> + for_each_cea_db(cea, i, start, end) {
> + db = &cea[i];
> + dbl = cea_db_payload_len(db);
> +
> + if (cea_db_tag(db) == VIDEO_BLOCK) {
> + video = db + 1;
> + video_len = dbl;
> + modes += do_cea_modes(connector, video, dbl);
> + } else if (cea_db_is_hdmi_vsdb(db)) {
> + hdmi = db;
> + hdmi_len = dbl;
> + } else if (cea_db_is_y420vdb(db)) {
> + const u8 *vdb420 = &db[2];
> +
> + /* Add 4:2:0(only) modes present in EDID */
> + modes += do_y420vdb_modes(connector,
> + vdb420,
> + dbl - 1);
> + }
> }
> }
> - }
>
> - /*
> - * We parse the HDMI VSDB after having added the cea modes as we will
> - * be patching their flags when the sink supports stereo 3D.
> - */
> - if (hdmi)
> - modes += do_hdmi_vsdb_modes(connector, hdmi, hdmi_len, video,
> - video_len);
> + /*
> + * We parse the HDMI VSDB after having added the cea modes as we will
> + * be patching their flags when the sink supports stereo 3D.
> + */
> + if (hdmi) {
> + modes += do_hdmi_vsdb_modes(connector, hdmi, hdmi_len, video,
> + video_len);
> + hdmi = NULL;
> + video = NULL;
> + hdmi_len = 0;
> + video_len = 0;
> + }
> +
> + /* move to next CEA extension block */
> + cea = drm_find_edid_extension(edid, CEA_EXT, &j);
> + if (!cea)
> + break;
> + }
>
> return modes;
> }
> --
> 2.17.1
--
Ville Syrjälä
Intel
