[PATCH v3] scsi: ufs: use an generic error code in ufshcd_set_dev_pwr_mode

[Kiwoong Kim <kwmad.kim@samsung.com>]

v2 -> v3: change the value of ret only if it's positive
v1 -> v2: modify the comment of ufshcd_set_dev_pwr_mode

The return value of ufshcd_set_dev_pwr_mode is given to
device pm core. However, the function currently returns a result
in scsi command and the device pm core doesn't understand it.
It might lead to unexpected behaviors of user land. I found
the return value led to platform reset in Android.

This patch is to use an generic code for SSU failures.

Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
---
 drivers/scsi/ufs/ufshcd.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1049e41..25e08a3 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8613,7 +8613,7 @@ static void ufshcd_hba_exit(struct ufs_hba *hba)
  * @pwr_mode: device power mode to set
  *
  * Returns 0 if requested power mode is set successfully
- * Returns non-zero if failed to set the requested power mode
+ * Returns < 0 if failed to set the requested power mode
  */
 static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
 				     enum ufs_dev_pwr_mode pwr_mode)
@@ -8667,8 +8667,11 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
 		sdev_printk(KERN_WARNING, sdp,
 			    "START_STOP failed for power mode: %d, result %x\n",
 			    pwr_mode, ret);
-		if (ret > 0 && scsi_sense_valid(&sshdr))
-			scsi_print_sense_hdr(sdp, NULL, &sshdr);
+		if (ret > 0) {
+			if (scsi_sense_valid(&sshdr))
+				scsi_print_sense_hdr(sdp, NULL, &sshdr);
+			ret = -EIO;
+		}
 	}
 
 	if (!ret)
-- 
2.7.4