scsi: ufs: Get a TM service response from the correct offset

When any UFS host controller receives a TM(Task Management) response
from a UFS device, UFS driver has been recognize like receiving a
message of "Task Management Function Complete"(00h) in all cases, so
far.  That means there is no pending task for a tag of the TM request
sent before in the UFS device.  That's because the byte offset 6 in TM
response which has been used to get a TM service response so far
represents just whether or not a TM transmission passes.

Regarding UFS spec, the correct byte offset to get TM service response
is 15, not 6.

I tested that UFS driver responds properly for the TM response from a
UFS device with an reference board with exynos8890, as follow: No
pending task -> Task Management Function Complete (00h) Pending task ->
Task Management Function Succeeded (08h)

[mkp: applied by hand]

Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: HeonGwang Chu <hg.chu@samsung.com>
Tested-by: : Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index b291fa6..845b874 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -327,6 +327,7 @@
 	MASK_QUERY_DATA_SEG_LEN         = 0xFFFF,
 	MASK_RSP_UPIU_DATA_SEG_LEN	= 0xFFFF,
 	MASK_RSP_EXCEPTION_EVENT        = 0x10000,
+	MASK_TM_SERVICE_RESP		= 0xFF,
 };
 
 /* Task management service response */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 66f0eb8..37f3c51 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3364,8 +3364,8 @@
 	if (ocs_value == OCS_SUCCESS) {
 		task_rsp_upiup = (struct utp_upiu_task_rsp *)
 				task_req_descp[index].task_rsp_upiu;
-		task_result = be32_to_cpu(task_rsp_upiup->header.dword_1);
-		task_result = ((task_result & MASK_TASK_RESPONSE) >> 8);
+		task_result = be32_to_cpu(task_rsp_upiup->output_param1);
+		task_result = task_result & MASK_TM_SERVICE_RESP;
 		if (resp)
 			*resp = (u8)task_result;
 	} else {