Only call scsi_set_resid() in case of an underflow. Do not call
scsi_set_resid() in case of an overflow.
Cc: Avri Altman <avri.altman@xxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Fixes: cb38845d90fc ("scsi: ufs: core: Set the residual byte count")
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
drivers/ufs/core/ufshcd.c | 19 ++++++++++++++++---
include/ufs/ufs.h | 6 ++++++
2 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index e31242fe0518..b27372f9b488 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -5241,12 +5241,25 @@ static inline int
ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp,
struct cq_entry *cqe)
{
+ bool overflow, underflow;
+ u8 upiu_flags;
int result = 0;
int scsi_status;
enum utp_ocs ocs;
-
- scsi_set_resid(lrbp->cmd,
- be32_to_cpu(lrbp->ucd_rsp_ptr->sr.residual_transfer_count));
+ u32 resid;
+
+ upiu_flags = be32_to_cpu(lrbp->ucd_rsp_ptr->header.dword_0) >> 16;
+ overflow = upiu_flags & UPIU_RSP_FLAG_OVERFLOW;
+ underflow = upiu_flags & UPIU_RSP_FLAG_UNDERFLOW;
+ resid = be32_to_cpu(lrbp->ucd_rsp_ptr->sr.residual_transfer_count);
+ WARN_ON_ONCE(overflow && underflow);
+ WARN_ON_ONCE(!overflow && !underflow && resid);
+ /*
+ * Test !overflow instead of underflow to support UFS devices that do
+ * not set either flag.
+ */
+ if (!overflow)
+ scsi_set_resid(lrbp->cmd, resid);
/* overall command status of utrd */
ocs = ufshcd_get_tr_ocs(lrbp, cqe);
diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
index 8316e2408ac3..bee5ccc6e7ce 100644
--- a/include/ufs/ufs.h
+++ b/include/ufs/ufs.h
@@ -104,6 +104,12 @@ enum {
UPIU_CMD_FLAGS_READ = 0x40,
};
+/* UPIU response flags */
+enum {
+ UPIU_RSP_FLAG_UNDERFLOW = 0x20,
+ UPIU_RSP_FLAG_OVERFLOW = 0x40,
+};
+
/* UPIU Task Attributes */
enum {
UPIU_TASK_ATTR_SIMPLE = 0x00,
