scsi: ufs: retry failed query flag requests

UFS flag query requests may fail sometimes due to timeouts etc.  Add a
wrapper function to retry up to 10 times in case of such failure,
similar to retries being made for attribute queries.
Reviewed-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NGilad Broner <gbroner@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufshcd.c

@@ -1660,6 +1660,29 @@ static inline void ufshcd_init_query(struct ufs_hba *hba,
 	(*request)->upiu_req.selector = selector;
 }
 
+static int ufshcd_query_flag_retry(struct ufs_hba *hba,
+	enum query_opcode opcode, enum flag_idn idn, bool *flag_res)
+{
+	int ret;
+	int retries;
+
+	for (retries = 0; retries < QUERY_REQ_RETRIES; retries++) {
+		ret = ufshcd_query_flag(hba, opcode, idn, flag_res);
+		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, opcode %d, idn %d, failed with error %d after %d retires\n",
+			__func__, opcode, idn, ret, retries);
+	return ret;
+}
+
 /**
  * ufshcd_query_flag() - API function for sending flag query requests
  * hba: per-adapter instance
@@ -1669,7 +1692,7 @@ static inline void ufshcd_init_query(struct ufs_hba *hba,
  *
  * Returns 0 for success, non-zero in case of failure
  */
-static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
+int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
 			enum flag_idn idn, bool *flag_res)
 {
 	struct ufs_query_req *request = NULL;
@@ -2654,17 +2677,12 @@ static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
  */
 static int ufshcd_complete_dev_init(struct ufs_hba *hba)
 {
-	int i, retries, err = 0;
+	int i;
+	int err;
 	bool flag_res = 1;
 
-	for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
-		/* Set the fDeviceInit flag */
-		err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_SET_FLAG,
-					QUERY_FLAG_IDN_FDEVICEINIT, NULL);
-		if (!err || err == -ETIMEDOUT)
-			break;
-		dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
-	}
+	err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+		QUERY_FLAG_IDN_FDEVICEINIT, NULL);
 	if (err) {
 		dev_err(hba->dev,
 			"%s setting fDeviceInit flag failed with error %d\n",
@@ -2672,18 +2690,11 @@ static int ufshcd_complete_dev_init(struct ufs_hba *hba)
 		goto out;
 	}
 
-	/* poll for max. 100 iterations for fDeviceInit flag to clear */
-	for (i = 0; i < 100 && !err && flag_res; i++) {
-		for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
-			err = ufshcd_query_flag(hba,
-					UPIU_QUERY_OPCODE_READ_FLAG,
-					QUERY_FLAG_IDN_FDEVICEINIT, &flag_res);
-			if (!err || err == -ETIMEDOUT)
-				break;
-			dev_dbg(hba->dev, "%s: error %d retrying\n", __func__,
-					err);
-		}
-	}
+	/* poll for max. 1000 iterations for fDeviceInit flag to clear */
+	for (i = 0; i < 1000 && !err && flag_res; i++)
+		err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_READ_FLAG,
+			QUERY_FLAG_IDN_FDEVICEINIT, &flag_res);
+
 	if (err)
 		dev_err(hba->dev,
 			"%s reading fDeviceInit flag failed with error %d\n",
@@ -3430,7 +3441,7 @@ static int ufshcd_enable_auto_bkops(struct ufs_hba *hba)
 	if (hba->auto_bkops_enabled)
 		goto out;
 
-	err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+	err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_SET_FLAG,
 			QUERY_FLAG_IDN_BKOPS_EN, NULL);
 	if (err) {
 		dev_err(hba->dev, "%s: failed to enable bkops %d\n",
@@ -3479,7 +3490,7 @@ static int ufshcd_disable_auto_bkops(struct ufs_hba *hba)
 		goto out;
 	}
 
-	err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_CLEAR_FLAG,
+	err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_CLEAR_FLAG,
 			QUERY_FLAG_IDN_BKOPS_EN, NULL);
 	if (err) {
 		dev_err(hba->dev, "%s: failed to disable bkops %d\n",
@@ -4450,8 +4461,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
 
 		/* clear any previous UFS device information */
 		memset(&hba->dev_info, 0, sizeof(hba->dev_info));
-		if (!ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,
-				       QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
+		if (!ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_READ_FLAG,
+				QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
 			hba->dev_info.f_power_on_wp_en = flag;
 
 		if (!hba->is_init_prefetch)

drivers/scsi/ufs/ufshcd.h

@@ -3,6 +3,7 @@
  *
  * This code is based on drivers/scsi/ufs/ufshcd.h
  * Copyright (C) 2011-2013 Samsung India Software Operations
+ * Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
  *
  * Authors:
  *	Santosh Yaraganavi <santosh.sy@samsung.com>
@@ -681,6 +682,9 @@ static inline int ufshcd_dme_peer_get(struct ufs_hba *hba,
 	return ufshcd_dme_get_attr(hba, attr_sel, mib_val, DME_PEER);
 }
 
+/* Expose Query-Request API */
+int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
+	enum flag_idn idn, bool *flag_res);
 int ufshcd_hold(struct ufs_hba *hba, bool async);
 void ufshcd_release(struct ufs_hba *hba);