[PATCH 6.1.y 1/3] drm/edid: parse VICs from CTA VDB early

[Sasha Levin <sashal@kernel.org>]

From: Jani Nikula <jani.nikula@intel.com>

[ Upstream commit c3292ab5fbd7045f019418b2ce1977891419ad28 ]

A number of places need access to the VICs. Just parse them early for
easy access. Gracefully handle multiple CTA VDBs. It's unlikely to have
more than one, but the CTA-861 references "Video Data Block(s)", so err
on the safe side.

Start parsing them now, convert users in follow-up to have fewer moving
parts in one go.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/7989b2b37837be68953c5d20afd3e93762bfd626.1672826282.git.jani.nikula@intel.com
Stable-dep-of: 0de95c96655c ("drm/amdgpu: Only enable HDMI audio if display supports it")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/drm_connector.c |  1 +
 drivers/gpu/drm/drm_edid.c      | 36 +++++++++++++++++++++++++++++++++
 include/drm/drm_connector.h     | 10 +++++++++
 3 files changed, 47 insertions(+)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index e49e2b0da6590..ca4c543234bbc 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -564,6 +564,7 @@ void drm_connector_cleanup(struct drm_connector *connector)
 	ida_free(&dev->mode_config.connector_ida, connector->index);
 
 	kfree(connector->display_info.bus_formats);
+	kfree(connector->display_info.vics);
 	drm_mode_object_unregister(dev, &connector->base);
 	kfree(connector->name);
 	connector->name = NULL;
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index b202bb197f316..511021179ecbd 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -5704,6 +5704,36 @@ drm_default_rgb_quant_range(const struct drm_display_mode *mode)
 }
 EXPORT_SYMBOL(drm_default_rgb_quant_range);
 
+/* CTA-861 Video Data Block (CTA VDB) */
+static void parse_cta_vdb(struct drm_connector *connector, const struct cea_db *db)
+{
+	struct drm_display_info *info = &connector->display_info;
+	int i, vic_index, len = cea_db_payload_len(db);
+	const u8 *svds = cea_db_data(db);
+	u8 *vics;
+
+	if (!len)
+		return;
+
+	/* Gracefully handle multiple VDBs, however unlikely that is */
+	vics = krealloc(info->vics, info->vics_len + len, GFP_KERNEL);
+	if (!vics)
+		return;
+
+	vic_index = info->vics_len;
+	info->vics_len += len;
+	info->vics = vics;
+
+	for (i = 0; i < len; i++) {
+		u8 vic = svd_to_vic(svds[i]);
+
+		if (!drm_valid_cea_vic(vic))
+			vic = 0;
+
+		info->vics[vic_index++] = vic;
+	}
+}
+
 static void drm_parse_vcdb(struct drm_connector *connector, const u8 *db)
 {
 	struct drm_display_info *info = &connector->display_info;
@@ -6023,6 +6053,8 @@ static void drm_parse_cea_ext(struct drm_connector *connector,
 			drm_parse_vcdb(connector, data);
 		else if (cea_db_is_hdmi_hdr_metadata_block(db))
 			drm_parse_hdr_metadata_block(connector, data);
+		else if (cea_db_tag(db) == CTA_DB_VIDEO)
+			parse_cta_vdb(connector, db);
 	}
 	cea_db_iter_end(&iter);
 }
@@ -6176,6 +6208,10 @@ static void drm_reset_display_info(struct drm_connector *connector)
 	info->mso_stream_count = 0;
 	info->mso_pixel_overlap = 0;
 	info->max_dsc_bpp = 0;
+
+	kfree(info->vics);
+	info->vics = NULL;
+	info->vics_len = 0;
 }
 
 static u32 update_display_info(struct drm_connector *connector,
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index b8ef80e6ce392..5dfde32447798 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -662,6 +662,16 @@ struct drm_display_info {
 	 * monitor's default value is used instead.
 	 */
 	u32 max_dsc_bpp;
+
+	/**
+	 * @vics: Array of vics_len VICs. Internal to EDID parsing.
+	 */
+	u8 *vics;
+
+	/**
+	 * @vics_len: Number of elements in vics. Internal to EDID parsing.
+	 */
+	int vics_len;
 };
 
 int drm_display_info_set_bus_formats(struct drm_display_info *info,
-- 
2.53.0