From 7c7154d60d8abe4b89b43e537e144d25d4cb4afa Mon Sep 17 00:00:00 2001
From: Jani Nikula <jani.nikula@intel.com>
Date: Tue, 3 May 2022 12:23:55 +0300
Subject: drm/edid: convert drm_edid_to_sad() to use cea db iter
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Git-commit: b07debc2a8ce7324c85479a28d145eaa05382286
Patch-mainline: v6.0-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849

Use the cea db iterator for short audio descriptors. We'll still stop at
the first audio data block, but not at the first CTA Extension if that
doesn't have the info.

Cc: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/237e4b1de1567903d37ce1d1bb830020b8fd6690.1651569697.git.jani.nikula@intel.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/drm_edid.c | 34 +++++++++-------------------------
 1 file changed, 9 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 7d6bf0b2bd9e..1ea27278652b 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -5007,40 +5007,21 @@ static void drm_edid_to_eld(struct drm_connector *connector,
  */
 int drm_edid_to_sad(const struct edid *edid, struct cea_sad **sads)
 {
+	const struct cea_db *db;
+	struct cea_db_iter iter;
 	int count = 0;
-	int i, start, end, dbl;
-	const u8 *cea;
-
-	cea = drm_find_cea_extension(edid);
-	if (!cea) {
-		DRM_DEBUG_KMS("SAD: no CEA Extension found\n");
-		return 0;
-	}
-
-	if (cea_revision(cea) < 3) {
-		DRM_DEBUG_KMS("SAD: wrong CEA revision\n");
-		return 0;
-	}
-
-	if (cea_db_offsets(cea, &start, &end)) {
-		DRM_DEBUG_KMS("SAD: invalid data block offsets\n");
-		return -EPROTO;
-	}
-
-	for_each_cea_db(cea, i, start, end) {
-		const u8 *db = &cea[i];
 
+	cea_db_iter_edid_begin(edid, &iter);
+	cea_db_iter_for_each(db, &iter) {
 		if (cea_db_tag(db) == CTA_DB_AUDIO) {
 			int j;
 
-			dbl = cea_db_payload_len(db);
-
-			count = dbl / 3; /* SAD is 3B */
+			count = cea_db_payload_len(db) / 3; /* SAD is 3B */
 			*sads = kcalloc(count, sizeof(**sads), GFP_KERNEL);
 			if (!*sads)
 				return -ENOMEM;
 			for (j = 0; j < count; j++) {
-				const u8 *sad = &db[1 + j * 3];
+				const u8 *sad = &db->data[j * 3];
 
 				(*sads)[j].format = (sad[0] & 0x78) >> 3;
 				(*sads)[j].channels = sad[0] & 0x7;
@@ -5050,6 +5031,9 @@ int drm_edid_to_sad(const struct edid *edid, struct cea_sad **sads)
 			break;
 		}
 	}
+	cea_db_iter_end(&iter);
+
+	DRM_DEBUG_KMS("Found %d Short Audio Descriptors\n", count);
 
 	return count;
 }
-- 
2.38.1