[PATCH v3 2/5] scsi: Add partition lookup by type GUID for SCSI devices

[Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com>]

Introduce scsi_get_blk_by_type_guid() function to enable SCSI
partition discovery using partition type GUID. This function scans
all available SCSI devices and searches for a partition matching the
specified type GUID.

Reviewed-by: Simon Glass <simon.glass@canonical.com>
Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com>
---
Changes in v3:
- No changes

Changes in v2:
- Compute blk_find_max_devnum(UCLASS_SCSI) only once in scsi_get_blk_by_type_guid()
---
 drivers/scsi/scsi-uclass.c | 28 ++++++++++++++++++++++++++--
 include/scsi.h             | 11 +++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/scsi-uclass.c b/drivers/scsi/scsi-uclass.c
index 39b4c7476d4..031dc01b9de 100644
--- a/drivers/scsi/scsi-uclass.c
+++ b/drivers/scsi/scsi-uclass.c
@@ -30,9 +30,10 @@ int scsi_get_blk_by_uuid(const char *uuid,
 			 struct disk_partition *part_info_ptr)
 {
 	struct blk_desc *blk;
-	int i, ret;
+	int i, ret, max;
 
-	for (i = 0; i < blk_find_max_devnum(UCLASS_SCSI) + 1; i++) {
+	max = blk_find_max_devnum(UCLASS_SCSI) + 1;
+	for (i = 0; i < max; i++) {
 		ret = blk_get_desc(UCLASS_SCSI, i, &blk);
 		if (ret)
 			continue;
@@ -47,6 +48,29 @@ int scsi_get_blk_by_uuid(const char *uuid,
 	return -ENODEV;
 }
 
+int scsi_get_blk_by_type_guid(const char *type_guid,
+			      struct blk_desc **blk_desc_ptr,
+			      struct disk_partition *part_info_ptr)
+{
+	struct blk_desc *blk;
+	int i, ret, max;
+
+	max = blk_find_max_devnum(UCLASS_SCSI) + 1;
+	for (i = 0; i < max; i++) {
+		ret = blk_get_desc(UCLASS_SCSI, i, &blk);
+		if (ret)
+			continue;
+
+		ret = part_get_info_by_type_guid(blk, type_guid, part_info_ptr);
+		if (ret > 0) {
+			*blk_desc_ptr = blk;
+			return 0;
+		}
+	}
+
+	return -ENODEV;
+}
+
 int scsi_bus_reset(struct udevice *dev)
 {
 	struct scsi_ops *ops = scsi_get_ops(dev);
diff --git a/include/scsi.h b/include/scsi.h
index 2520a8b8fe6..83aaf0a70f6 100644
--- a/include/scsi.h
+++ b/include/scsi.h
@@ -366,6 +366,17 @@ int scsi_scan_dev(struct udevice *dev, bool verbose);
 int scsi_get_blk_by_uuid(const char *uuid, struct blk_desc **blk_desc_ptr,
 			 struct disk_partition *part_info_ptr);
 
+/**
+ * scsi_get_blk_by_type_guid() - Provides SCSI partition information by type GUID.
+ *
+ * @type_guid:		Type GUID of the partition for fetching its info
+ * @blk_desc_ptr:	Provides the blk descriptor
+ * @part_info_ptr:	Provides partition info
+ * Return: 0 if OK, -ve on error
+ */
+int scsi_get_blk_by_type_guid(const char *type_guid, struct blk_desc **blk_desc_ptr,
+			      struct disk_partition *part_info_ptr);
+
 #define SCSI_IDENTIFY					0xC0  /* not used */
 
 /* Hardware errors  */

-- 
2.34.1