drm/edid: Extract drm_edid_decode_mfg_id()

Make the PNPID decoding available for other users.

Cc: [e-mail]
Reviewed-by: Jani Nikula <[e-mail]>
Signed-off-by: Ville Syrjälä <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

include/drm/drm_edid.h

···
 }
 
 /**
+ * drm_edid_decode_mfg_id - Decode the manufacturer ID
+ * @mfg_id: The manufacturer ID
+ * @vend: A 4-byte buffer to store the 3-letter vendor string plus a '\0'
+ *	  termination
+ */
+static inline const char *drm_edid_decode_mfg_id(u16 mfg_id, char vend[4])
+{
+	vend[0] = '@' + ((mfg_id >> 10) & 0x1f);
+	vend[1] = '@' + ((mfg_id >> 5) & 0x1f);
+	vend[2] = '@' + ((mfg_id >> 0) & 0x1f);
+	vend[3] = '\0';
+
+	return vend;
+}
+
+/**
  * drm_edid_encode_panel_id - Encode an ID for matching against drm_edid_get_panel_id()
  * @vend_chr_0: First character of the vendor string.
  * @vend_chr_1: Second character of the vendor string.
···
 static inline void drm_edid_decode_panel_id(u32 panel_id, char vend[4], u16 *product_id)
 {
 	*product_id = (u16)(panel_id & 0xffff);
-	vend[0] = '@' + ((panel_id >> 26) & 0x1f);
-	vend[1] = '@' + ((panel_id >> 21) & 0x1f);
-	vend[2] = '@' + ((panel_id >> 16) & 0x1f);
-	vend[3] = '\0';
+	drm_edid_decode_mfg_id(panel_id >> 16, vend);
 }
 
 bool drm_probe_ddc(struct i2c_adapter *adapter);