[PATCH v4 15/15] scsi: ufs: add wrapper for retrying sending query attribute

[Yaniv Gardi <ygardi@codeaurora.org>]

Sometimes queries from the device might return a failure so it is
recommended to retry sending the query, before giving up.
This change adds a wrapper to retry sending a query attribute,
in cases where we need to wait longer, before we continue,
or before reporting a failure.

Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>

---
 drivers/scsi/ufs/ufshcd.c | 51 ++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 44 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c87bd4b..98607e4 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1824,6 +1824,43 @@ out:
 }
 
 /**
+ * ufshcd_query_attr_retry() - API function for sending query
+ * attribute with retries
+ * @hba: per-adapter instance
+ * @opcode: attribute opcode
+ * @idn: attribute idn to access
+ * @index: index field
+ * @selector: selector field
+ * @attr_val: the attribute value after the query request
+ * completes
+ *
+ * Returns 0 for success, non-zero in case of failure
+*/
+static int ufshcd_query_attr_retry(struct ufs_hba *hba,
+	enum query_opcode opcode, enum attr_idn idn, u8 index, u8 selector,
+	u32 *attr_val)
+{
+	int ret = 0;
+	u32 retries;
+
+	 for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
+		ret = ufshcd_query_attr(hba, opcode, idn, index,
+						selector, attr_val);
+		if (ret)
+			dev_dbg(hba->dev, "%s: failed with error %d, retries %d\n",
+				__func__, ret, retries);
+		else
+			break;
+	}
+
+	if (ret)
+		dev_err(hba->dev,
+			"%s: query attribute, idn %d, failed with error %d after %d retires\n",
+			__func__, idn, ret, QUERY_REQ_RETRIES);
+	return ret;
+}
+
+/**
  * ufshcd_query_descriptor - API function for sending descriptor requests
  * hba: per-adapter instance
  * opcode: attribute opcode
@@ -3404,7 +3441,7 @@ static int ufshcd_disable_ee(struct ufs_hba *hba, u16 mask)
 
 	val = hba->ee_ctrl_mask & ~mask;
 	val &= 0xFFFF; /* 2 bytes */
-	err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+	err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
 			QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &val);
 	if (!err)
 		hba->ee_ctrl_mask &= ~mask;
@@ -3432,7 +3469,7 @@ static int ufshcd_enable_ee(struct ufs_hba *hba, u16 mask)
 
 	val = hba->ee_ctrl_mask | mask;
 	val &= 0xFFFF; /* 2 bytes */
-	err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+	err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
 			QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &val);
 	if (!err)
 		hba->ee_ctrl_mask |= mask;
@@ -3538,7 +3575,7 @@ static void  ufshcd_force_reset_auto_bkops(struct ufs_hba *hba)
 
 static inline int ufshcd_get_bkops_status(struct ufs_hba *hba, u32 *status)
 {
-	return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+	return ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
 			QUERY_ATTR_IDN_BKOPS_STATUS, 0, 0, status);
 }
 
@@ -3601,7 +3638,7 @@ static int ufshcd_urgent_bkops(struct ufs_hba *hba)
 
 static inline int ufshcd_get_ee_status(struct ufs_hba *hba, u32 *status)
 {
-	return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+	return ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
 			QUERY_ATTR_IDN_EE_STATUS, 0, 0, status);
 }
 
@@ -4357,9 +4394,9 @@ static void ufshcd_init_icc_levels(struct ufs_hba *hba)
 	dev_dbg(hba->dev, "%s: setting icc_level 0x%x",
 			__func__, hba->init_prefetch_data.icc_level);
 
-	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
-			QUERY_ATTR_IDN_ACTIVE_ICC_LVL, 0, 0,
-			&hba->init_prefetch_data.icc_level);
+	ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+		QUERY_ATTR_IDN_ACTIVE_ICC_LVL, 0, 0,
+		&hba->init_prefetch_data.icc_level);
 
 	if (ret)
 		dev_err(hba->dev,
-- 
1.8.5.2

-- 
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