scsi: ufs: sysfs: device descriptor

This patch introduces a sysfs group entry for the UFS device descriptor
parameters. The group adds "device_descriptor" folder under the UFS driver
sysfs entry (/sys/bus/platform/drivers/ufshcd/*). The parameters are shown
as hexadecimal numbers. The full information about the parameters could be
found at UFS specifications 2.1.

Signed-off-by: Stanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e7621a0a..540a431 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2989,12 +2989,12 @@ EXPORT_SYMBOL(ufshcd_map_desc_id_to_length);
  *
  * Return 0 in case of success, non-zero otherwise
  */
-static int ufshcd_read_desc_param(struct ufs_hba *hba,
-				  enum desc_idn desc_id,
-				  int desc_index,
-				  u8 param_offset,
-				  u8 *param_read_buf,
-				  u8 param_size)
+int ufshcd_read_desc_param(struct ufs_hba *hba,
+			   enum desc_idn desc_id,
+			   int desc_index,
+			   u8 param_offset,
+			   u8 *param_read_buf,
+			   u8 param_size)
 {
 	int ret;
 	u8 *desc_buf;