disk: Provide API to get partition by name for specific type

There is already existing function part_get_info_by_name().
But sometimes user is particularly interested in looking for only
specific partition type. This patch implements such an API that
provides partition searching by name for specified partition type.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

disk/part.c

@@ -21,6 +21,9 @@
 #define PRINTF(fmt,args...)
 #endif
 
+/* Check all partition types */
+#define PART_TYPE_ALL		-1
+
 DECLARE_GLOBAL_DATA_PTR;
 
 #ifdef HAVE_BLOCK_DEVICE
@@ -626,8 +629,8 @@ cleanup:
 	return ret;
 }
 
-int part_get_info_by_name(struct blk_desc *dev_desc, const char *name,
-	disk_partition_t *info)
+int part_get_info_by_name_type(struct blk_desc *dev_desc, const char *name,
+			       disk_partition_t *info, int part_type)
 {
 	struct part_driver *first_drv =
 		ll_entry_start(struct part_driver, part_driver);
@@ -638,6 +641,8 @@ int part_get_info_by_name(struct blk_desc *dev_desc, const char *name,
 		int ret;
 		int i;
 		for (i = 1; i < part_drv->max_entries; i++) {
+			if (part_type >= 0 && part_type != part_drv->part_type)
+				break;
 			ret = part_drv->get_info(dev_desc, i, info);
 			if (ret != 0) {
 				/* no more entries in table */
@@ -652,6 +657,12 @@ int part_get_info_by_name(struct blk_desc *dev_desc, const char *name,
 	return -1;
 }
 
+int part_get_info_by_name(struct blk_desc *dev_desc, const char *name,
+			  disk_partition_t *info)
+{
+	return part_get_info_by_name_type(dev_desc, name, info, PART_TYPE_ALL);
+}
+
 void part_set_generic_name(const struct blk_desc *dev_desc,
 	int part_num, char *name)
 {

include/part.h

@@ -173,6 +173,21 @@ int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 			    struct blk_desc **dev_desc,
 			    disk_partition_t *info, int allow_whole_dev);
 
+/**
+ * part_get_info_by_name_type() - Search for a partition by name
+ *                                for only specified partition type
+ *
+ * @param dev_desc - block device descriptor
+ * @param gpt_name - the specified table entry name
+ * @param info - returns the disk partition info
+ * @param part_type - only search in partitions of this type
+ *
+ * @return - the partition number on match (starting on 1), -1 on no match,
+ * otherwise error
+ */
+int part_get_info_by_name_type(struct blk_desc *dev_desc, const char *name,
+			       disk_partition_t *info, int part_type);
+
 /**
  * part_get_info_by_name() - Search for a partition by name
  *                           among all available registered partitions