On Thu, Feb 24, 2022 at 10:16:23PM +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 | 110 ++++++++++++++++++++----------------- > 1 file changed, 60 insertions(+), 50 deletions(-) > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c > index a504542238ed..19426f28b411 100644 > --- a/drivers/gpu/drm/drm_edid.c > +++ b/drivers/gpu/drm/drm_edid.c > @@ -3353,16 +3353,14 @@ const u8 *drm_find_edid_extension(const struct edid *edid, > return edid_ext; > } > > -static const u8 *drm_find_cea_extension(const struct edid *edid) > +static const u8 *drm_find_cea_extension(const struct edid *edid, int *ext_index) > { > const struct displayid_block *block; > struct displayid_iter iter; > const u8 *cea; > - int ext_index = 0; > > - /* Look for a top level CEA extension block */ > - /* FIXME: make callers iterate through multiple CEA ext blocks? */ > - cea = drm_find_edid_extension(edid, CEA_EXT, &ext_index); > + /* Look for a CEA extension block from ext_index */ > + cea = drm_find_edid_extension(edid, CEA_EXT, ext_index); > if (cea) > return cea; > > @@ -3643,10 +3641,10 @@ add_alternate_cea_modes(struct drm_connector *connector, struct edid *edid) > struct drm_device *dev = connector->dev; > struct drm_display_mode *mode, *tmp; > LIST_HEAD(list); > - int modes = 0; > + int modes = 0, ext_index = 0; > > /* Don't add CEA modes if the CEA extension block is missing */ > - if (!drm_find_cea_extension(edid)) > + if (!drm_find_cea_extension(edid, &ext_index)) > return 0; > > /* > @@ -4321,46 +4319,58 @@ static void drm_parse_y420cmdb_bitmap(struct drm_connector *connector, > static int > add_cea_modes(struct drm_connector *connector, struct edid *edid) > { > - const u8 *cea = drm_find_cea_extension(edid); > + const u8 *cea = NULL; > const u8 *db, *hdmi = NULL, *video = NULL; > u8 dbl, hdmi_len, video_len = 0; > - int modes = 0; > + int modes = 0, ext_index = 0; > > - if (cea && cea_revision(cea) >= 3) { > - int i, start, end; > + for (;;) { > + cea = drm_find_cea_extension(edid, &ext_index); Please split this into two patches: 1. do the *ext_index stuff 2. do the loop > > - if (cea_db_offsets(cea, &start, &end)) > - return 0; > + if (!cea) > + break; > > - for_each_cea_db(cea, i, start, end) { > - db = &cea[i]; > - dbl = cea_db_payload_len(db); > + if (cea && cea_revision(cea) >= 3) { > + int i, start, end; > + > + 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) { Looks like you're potentially using stale information here from previous loops. Please move all the possible variables to a tighter scope so this can't happen. > + modes += do_hdmi_vsdb_modes(connector, hdmi, hdmi_len, video, > + video_len); > + hdmi = NULL; > + video = NULL; > + hdmi_len = 0; > + video_len = 0; > + } > + } > > return modes; > } > @@ -4562,7 +4572,7 @@ static void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid) > uint8_t *eld = connector->eld; > const u8 *cea; > const u8 *db; > - int total_sad_count = 0; > + int total_sad_count = 0, ext_index = 0; > int mnl; > int dbl; > > @@ -4571,7 +4581,7 @@ static void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid) > if (!edid) > return; > > - cea = drm_find_cea_extension(edid); > + cea = drm_find_cea_extension(edid, &ext_index); > if (!cea) { > DRM_DEBUG_KMS("ELD: no CEA Extension found\n"); > return; > @@ -4655,11 +4665,11 @@ static void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid) > */ > int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads) > { > - int count = 0; > + int count = 0, ext_index = 0; > int i, start, end, dbl; > const u8 *cea; > > - cea = drm_find_cea_extension(edid); > + cea = drm_find_cea_extension(edid, &ext_index); > if (!cea) { > DRM_DEBUG_KMS("SAD: no CEA Extension found\n"); > return 0; > @@ -4717,11 +4727,11 @@ EXPORT_SYMBOL(drm_edid_to_sad); > */ > int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb) > { > - int count = 0; > + int count = 0, ext_index = 0; > int i, start, end, dbl; > const u8 *cea; > > - cea = drm_find_cea_extension(edid); > + cea = drm_find_cea_extension(edid, &ext_index); > if (!cea) { > DRM_DEBUG_KMS("SAD: no CEA Extension found\n"); > return 0; > @@ -4813,10 +4823,10 @@ EXPORT_SYMBOL(drm_av_sync_delay); > bool drm_detect_hdmi_monitor(struct edid *edid) > { > const u8 *edid_ext; > - int i; > + int i, ext_index = 0; > int start_offset, end_offset; > > - edid_ext = drm_find_cea_extension(edid); > + edid_ext = drm_find_cea_extension(edid, &ext_index); > if (!edid_ext) > return false; > > @@ -4851,11 +4861,11 @@ EXPORT_SYMBOL(drm_detect_hdmi_monitor); > bool drm_detect_monitor_audio(struct edid *edid) > { > const u8 *edid_ext; > - int i, j; > + int i, j, ext_index = 0; > bool has_audio = false; > int start_offset, end_offset; > > - edid_ext = drm_find_cea_extension(edid); > + edid_ext = drm_find_cea_extension(edid, &ext_index); > if (!edid_ext) > goto end; > > @@ -5177,9 +5187,9 @@ static void drm_parse_cea_ext(struct drm_connector *connector, > { > struct drm_display_info *info = &connector->display_info; > const u8 *edid_ext; > - int i, start, end; > + int i, start, end, ext_index = 0; > > - edid_ext = drm_find_cea_extension(edid); > + edid_ext = drm_find_cea_extension(edid, &ext_index); > if (!edid_ext) > return; > > -- > 2.17.1 -- Ville Syrjälä Intel