[v2,3/3] drm/edid: parse HF-EEODB CEA extension block

Commit Message

Lee Shawn C Feb. 22, 2022, 2:02 p.m. UTC

While adding CEA modes, try to get available EEODB block
number. Then based on it to parse numbers of ext blocks,
retrieve CEA information and add more CEA modes.

Signed-off-by: Lee Shawn C <[e-mail]>
---
 drivers/gpu/drm/drm_displayid.c |  5 ++++-
 drivers/gpu/drm/drm_edid.c      | 34 ++++++++++++++++++---------------
 include/drm/drm_edid.h          |  2 +-
 3 files changed, 24 insertions(+), 17 deletions(-)

Patch

diff --git a/drivers/gpu/drm/drm_displayid.c b/drivers/gpu/drm/drm_displayid.c
index 32da557b960f..dc649a9efaa2 100644
--- a/drivers/gpu/drm/drm_displayid.c
+++ b/drivers/gpu/drm/drm_displayid.c
@@ -37,7 +37,10 @@  static const u8 *drm_find_displayid_extension(const struct edid *edid,
 					      int *length, int *idx,
 					      int *ext_index)
 {
-	const u8 *displayid = drm_find_edid_extension(edid, DISPLAYID_EXT, ext_index);
+	const u8 *displayid = drm_find_edid_extension(edid,
+						      DISPLAYID_EXT,
+						      ext_index,
+						      edid->extensions);
 	const struct displayid_header *base;
 	int ret;
 
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index f8514783d089..bb050d171bb8 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -3364,23 +3364,23 @@  add_detailed_modes(struct drm_connector *connector, struct edid *edid,
  * Search EDID for CEA extension block.
  */
 const u8 *drm_find_edid_extension(const struct edid *edid,
-				  int ext_id, int *ext_index)
+				  int ext_id, int *ext_index, int num_ext_blk)
 {
 	const u8 *edid_ext = NULL;
 	int i;
 
 	/* No EDID or EDID extensions */
-	if (edid == NULL || edid->extensions == 0)
+	if (edid == NULL || edid->extensions == 0 || *ext_index >= num_ext_blk)
 		return NULL;
 
 	/* Find CEA extension */
-	for (i = *ext_index; i < edid->extensions; i++) {
+	for (i = *ext_index; i < num_ext_blk; i++) {
 		edid_ext = (const u8 *)edid + EDID_LENGTH * (i + 1);
 		if (edid_ext[0] == ext_id)
 			break;
 	}
 
-	if (i >= edid->extensions)
+	if (i >= num_ext_blk)
 		return NULL;
 
 	*ext_index = i + 1;
@@ -3388,14 +3388,15 @@  const u8 *drm_find_edid_extension(const struct edid *edid,
 	return edid_ext;
 }
 
-static const u8 *drm_find_cea_extension(const struct edid *edid, int *ext_index)
+static const u8 *drm_find_cea_extension(const struct edid *edid,
+					int *ext_index, int num_ext_blk)
 {
 	const struct displayid_block *block;
 	struct displayid_iter iter;
 	const u8 *cea;
 
 	/* Look for a CEA extension block from ext_index */
-	cea = drm_find_edid_extension(edid, CEA_EXT, ext_index);
+	cea = drm_find_edid_extension(edid, CEA_EXT, ext_index, num_ext_blk);
 	if (cea)
 		return cea;
 
@@ -3679,7 +3680,7 @@  add_alternate_cea_modes(struct drm_connector *connector, struct edid *edid)
 	int modes = 0, ext_index = 0;
 
 	/* Don't add CEA modes if the CEA extension block is missing */
-	if (!drm_find_cea_extension(edid, &ext_index))
+	if (!drm_find_cea_extension(edid, &ext_index, edid->extensions))
 		return 0;
 
 	/*
@@ -4376,11 +4377,14 @@  add_cea_modes(struct drm_connector *connector, struct edid *edid)
 {
 	const u8 *cea = NULL;
 	const u8 *db, *hdmi = NULL, *video = NULL;
-	u8 dbl, hdmi_len, video_len = 0;
+	u8 dbl, hdmi_len, video_len = 0, num_ext_blk = edid->extensions;
 	int modes = 0, j = 0;
 
+	if (num_ext_blk && drm_edid_is_hf_eeodb_blk_available(edid))
+		num_ext_blk = drm_edid_read_hf_eeodb_blk_size(edid);
+
 	for (;;) {
-		cea = drm_find_cea_extension(edid, &j);
+		cea = drm_find_cea_extension(edid, &j, num_ext_blk);
 
 		if (!cea)
 			break;
@@ -4636,7 +4640,7 @@  static void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
 	if (!edid)
 		return;
 
-	cea = drm_find_cea_extension(edid, &ext_index);
+	cea = drm_find_cea_extension(edid, &ext_index, edid->extensions);
 	if (!cea) {
 		DRM_DEBUG_KMS("ELD: no CEA Extension found\n");
 		return;
@@ -4724,7 +4728,7 @@  int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads)
 	int i, start, end, dbl;
 	const u8 *cea;
 
-	cea = drm_find_cea_extension(edid, &ext_index);
+	cea = drm_find_cea_extension(edid, &ext_index, edid->extensions);
 	if (!cea) {
 		DRM_DEBUG_KMS("SAD: no CEA Extension found\n");
 		return 0;
@@ -4786,7 +4790,7 @@  int drm_edid_to_speaker_allocation(struct edid *edid, u8 **sadb)
 	int i, start, end, dbl;
 	const u8 *cea;
 
-	cea = drm_find_cea_extension(edid, &ext_index);
+	cea = drm_find_cea_extension(edid, &ext_index, edid->extensions);
 	if (!cea) {
 		DRM_DEBUG_KMS("SAD: no CEA Extension found\n");
 		return 0;
@@ -4881,7 +4885,7 @@  bool drm_detect_hdmi_monitor(struct edid *edid)
 	int i, ext_index = 0;
 	int start_offset, end_offset;
 
-	edid_ext = drm_find_cea_extension(edid, &ext_index);
+	edid_ext = drm_find_cea_extension(edid, &ext_index, edid->extensions);
 	if (!edid_ext)
 		return false;
 
@@ -4920,7 +4924,7 @@  bool drm_detect_monitor_audio(struct edid *edid)
 	bool has_audio = false;
 	int start_offset, end_offset;
 
-	edid_ext = drm_find_cea_extension(edid, &ext_index);
+	edid_ext = drm_find_cea_extension(edid, &ext_index, edid->extensions);
 	if (!edid_ext)
 		goto end;
 
@@ -5232,7 +5236,7 @@  static void drm_parse_cea_ext(struct drm_connector *connector,
 	const u8 *edid_ext;
 	int i, start, end, ext_index = 0;
 
-	edid_ext = drm_find_cea_extension(edid, &ext_index);
+	edid_ext = drm_find_cea_extension(edid, &ext_index, edid->extensions);
 	if (!edid_ext)
 		return;
 
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
index ba2812432ead..4dbfbb531dfd 100644
--- a/include/drm/drm_edid.h
+++ b/include/drm/drm_edid.h
@@ -591,7 +591,7 @@  struct drm_display_mode *
 drm_display_mode_from_cea_vic(struct drm_device *dev,
 			      u8 video_code);
 const u8 *drm_find_edid_extension(const struct edid *edid,
-				  int ext_id, int *ext_index);
+				  int ext_id, int *ext_index, int num_ext_blk);
 
 bool drm_edid_is_hf_eeodb_blk_available(const struct edid *edid);
 u8 drm_edid_read_hf_eeodb_blk_size(const struct edid *edid);