1 files changed, 114 insertions, 33 deletions

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 923c4423151c..ea77577a3786 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -102,6 +102,11 @@ struct detailed_mode_closure {
 	int modes;
 };
 
+struct drm_edid_match_closure {
+	const struct drm_edid_ident *ident;
+	bool matched;
+};
+
 #define LEVEL_DMT	0
 #define LEVEL_GTF	1
 #define LEVEL_GTF2	2
@@ -109,13 +114,15 @@ struct detailed_mode_closure {
 
 #define EDID_QUIRK(vend_chr_0, vend_chr_1, vend_chr_2, product_id, _quirks) \
 { \
-	.panel_id = drm_edid_encode_panel_id(vend_chr_0, vend_chr_1, vend_chr_2, \
-					     product_id), \
+	.ident = { \
+		.panel_id = drm_edid_encode_panel_id(vend_chr_0, vend_chr_1, \
+						     vend_chr_2, product_id), \
+	}, \
 	.quirks = _quirks \
 }
 
 static const struct edid_quirk {
-	u32 panel_id;
+	const struct drm_edid_ident ident;
 	u32 quirks;
 } edid_quirk_list[] = {
 	/* Acer AL1706 */
@@ -2749,8 +2756,27 @@ const struct drm_edid *drm_edid_read(struct drm_connector *connector)
 }
 EXPORT_SYMBOL(drm_edid_read);
 
-static u32 edid_extract_panel_id(const struct edid *edid)
+/**
+ * drm_edid_get_panel_id - Get a panel's ID from EDID
+ * @drm_edid: EDID that contains panel ID.
+ *
+ * This function uses the first block of the EDID of a panel and (assuming
+ * that the EDID is valid) extracts the ID out of it. The ID is a 32-bit value
+ * (16 bits of manufacturer ID and 16 bits of per-manufacturer ID) that's
+ * supposed to be different for each different modem of panel.
+ *
+ * Return: A 32-bit ID that should be different for each make/model of panel.
+ *         See the functions drm_edid_encode_panel_id() and
+ *         drm_edid_decode_panel_id() for some details on the structure of this
+ *         ID. Return 0 if the EDID size is less than a base block.
+ */
+u32 drm_edid_get_panel_id(const struct drm_edid *drm_edid)
 {
+	const struct edid *edid = drm_edid->edid;
+
+	if (drm_edid->size < EDID_LENGTH)
+		return 0;
+
 	/*
 	 * We represent the ID as a 32-bit number so it can easily be compared
 	 * with "==".
@@ -2768,60 +2794,54 @@ static u32 edid_extract_panel_id(const struct edid *edid)
 	       (u32)edid->mfg_id[1] << 16   |
 	       (u32)EDID_PRODUCT_ID(edid);
 }
+EXPORT_SYMBOL(drm_edid_get_panel_id);
 
 /**
- * drm_edid_get_panel_id - Get a panel's ID through DDC
+ * drm_edid_read_base_block - Get a panel's EDID base block
  * @adapter: I2C adapter to use for DDC
  *
- * This function reads the first block of the EDID of a panel and (assuming
- * that the EDID is valid) extracts the ID out of it. The ID is a 32-bit value
- * (16 bits of manufacturer ID and 16 bits of per-manufacturer ID) that's
- * supposed to be different for each different modem of panel.
+ * This function returns the drm_edid containing the first block of the EDID of
+ * a panel.
  *
  * This function is intended to be used during early probing on devices where
  * more than one panel might be present. Because of its intended use it must
- * assume that the EDID of the panel is correct, at least as far as the ID
- * is concerned (in other words, we don't process any overrides here).
+ * assume that the EDID of the panel is correct, at least as far as the base
+ * block is concerned (in other words, we don't process any overrides here).
+ *
+ * Caller should call drm_edid_free() after use.
  *
  * NOTE: it's expected that this function and drm_do_get_edid() will both
  * be read the EDID, but there is no caching between them. Since we're only
  * reading the first block, hopefully this extra overhead won't be too big.
  *
- * Return: A 32-bit ID that should be different for each make/model of panel.
- *         See the functions drm_edid_encode_panel_id() and
- *         drm_edid_decode_panel_id() for some details on the structure of this
- *         ID.
+ * WARNING: Only use this function when the connector is unknown. For example,
+ * during the early probe of panel. The EDID read from the function is temporary
+ * and should be replaced by the full EDID returned from other drm_edid_read.
+ *
+ * Return: Pointer to allocated EDID base block, or NULL on any failure.
  */
-
-u32 drm_edid_get_panel_id(struct i2c_adapter *adapter)
+const struct drm_edid *drm_edid_read_base_block(struct i2c_adapter *adapter)
 {
 	enum edid_block_status status;
 	void *base_block;
-	u32 panel_id = 0;
-
-	/*
-	 * There are no manufacturer IDs of 0, so if there is a problem reading
-	 * the EDID then we'll just return 0.
-	 */
 
 	base_block = kzalloc(EDID_LENGTH, GFP_KERNEL);
 	if (!base_block)
-		return 0;
+		return NULL;
 
 	status = edid_block_read(base_block, 0, drm_do_probe_ddc_edid, adapter);
 
 	edid_block_status_print(status, base_block, 0);
 
-	if (edid_block_status_valid(status, edid_block_tag(base_block)))
-		panel_id = edid_extract_panel_id(base_block);
-	else
+	if (!edid_block_status_valid(status, edid_block_tag(base_block))) {
 		edid_block_dump(KERN_NOTICE, base_block, 0);
+		kfree(base_block);
+		return NULL;
+	}
 
-	kfree(base_block);
-
-	return panel_id;
+	return _drm_edid_alloc(base_block, EDID_LENGTH);
 }
-EXPORT_SYMBOL(drm_edid_get_panel_id);
+EXPORT_SYMBOL(drm_edid_read_base_block);
 
 /**
  * drm_get_edid_switcheroo - get EDID data for a vga_switcheroo output
@@ -2903,16 +2923,17 @@ EXPORT_SYMBOL(drm_edid_duplicate);
  * @drm_edid: EDID to process
  *
  * This tells subsequent routines what fixes they need to apply.
+ *
+ * Return: A u32 represents the quirks to apply.
  */
 static u32 edid_get_quirks(const struct drm_edid *drm_edid)
 {
-	u32 panel_id = edid_extract_panel_id(drm_edid->edid);
 	const struct edid_quirk *quirk;
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(edid_quirk_list); i++) {
 		quirk = &edid_quirk_list[i];
-		if (quirk->panel_id == panel_id)
+		if (drm_edid_match(drm_edid, &quirk->ident))
 			return quirk->quirks;
 	}
 
@@ -5443,6 +5464,66 @@ drm_parse_hdmi_vsdb_audio(struct drm_connector *connector, const u8 *db)
 }
 
 static void
+match_identity(const struct detailed_timing *timing, void *data)
+{
+	struct drm_edid_match_closure *closure = data;
+	unsigned int i;
+	const char *name = closure->ident->name;
+	unsigned int name_len = strlen(name);
+	const char *desc = timing->data.other_data.data.str.str;
+	unsigned int desc_len = ARRAY_SIZE(timing->data.other_data.data.str.str);
+
+	if (name_len > desc_len ||
+	    !(is_display_descriptor(timing, EDID_DETAIL_MONITOR_NAME) ||
+	      is_display_descriptor(timing, EDID_DETAIL_MONITOR_STRING)))
+		return;
+
+	if (strncmp(name, desc, name_len))
+		return;
+
+	for (i = name_len; i < desc_len; i++) {
+		if (desc[i] == '\n')
+			break;
+		/* Allow white space before EDID string terminator. */
+		if (!isspace(desc[i]))
+			return;
+	}
+
+	closure->matched = true;
+}
+
+/**
+ * drm_edid_match - match drm_edid with given identity
+ * @drm_edid: EDID
+ * @ident: the EDID identity to match with
+ *
+ * Check if the EDID matches with the given identity.
+ *
+ * Return: True if the given identity matched with EDID, false otherwise.
+ */
+bool drm_edid_match(const struct drm_edid *drm_edid,
+		    const struct drm_edid_ident *ident)
+{
+	if (!drm_edid || drm_edid_get_panel_id(drm_edid) != ident->panel_id)
+		return false;
+
+	/* Match with name only if it's not NULL. */
+	if (ident->name) {
+		struct drm_edid_match_closure closure = {
+			.ident = ident,
+			.matched = false,
+		};
+
+		drm_for_each_detailed_block(drm_edid, match_identity, &closure);
+
+		return closure.matched;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(drm_edid_match);
+
+static void
 monitor_name(const struct detailed_timing *timing, void *data)
 {
 	const char **res = data;