1 files changed, 42 insertions, 20 deletions

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 5d60a868830d..648a44675880 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -183,6 +183,7 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on);
 static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba);
 static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba);
+static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba);
 static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
 static irqreturn_t ufshcd_intr(int irq, void *__hba);
 static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
@@ -972,6 +973,8 @@ ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
 
 	ufshcd_hold(hba, false);
 	mutex_lock(&hba->uic_cmd_mutex);
+	ufshcd_add_delay_before_dme_cmd(hba);
+
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	ret = __ufshcd_send_uic_cmd(hba, uic_cmd);
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
@@ -2058,6 +2061,37 @@ static int ufshcd_dme_link_startup(struct ufs_hba *hba)
 	return ret;
 }
 
+static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba)
+{
+	#define MIN_DELAY_BEFORE_DME_CMDS_US	1000
+	unsigned long min_sleep_time_us;
+
+	if (!(hba->quirks & UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS))
+		return;
+
+	/*
+	 * last_dme_cmd_tstamp will be 0 only for 1st call to
+	 * this function
+	 */
+	if (unlikely(!ktime_to_us(hba->last_dme_cmd_tstamp))) {
+		min_sleep_time_us = MIN_DELAY_BEFORE_DME_CMDS_US;
+	} else {
+		unsigned long delta =
+			(unsigned long) ktime_to_us(
+				ktime_sub(ktime_get(),
+				hba->last_dme_cmd_tstamp));
+
+		if (delta < MIN_DELAY_BEFORE_DME_CMDS_US)
+			min_sleep_time_us =
+				MIN_DELAY_BEFORE_DME_CMDS_US - delta;
+		else
+			return; /* no more delay required */
+	}
+
+	/* allow sleep for extra 50us if needed */
+	usleep_range(min_sleep_time_us, min_sleep_time_us + 50);
+}
+
 /**
  * ufshcd_dme_set_attr - UIC command for DME_SET, DME_PEER_SET
  * @hba: per adapter instance
@@ -2157,6 +2191,7 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
 
 	mutex_lock(&hba->uic_cmd_mutex);
 	init_completion(&uic_async_done);
+	ufshcd_add_delay_before_dme_cmd(hba);
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	hba->uic_async_done = &uic_async_done;
@@ -4225,22 +4260,15 @@ static struct scsi_host_template ufshcd_driver_template = {
 static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
 				   int ua)
 {
-	int ret = 0;
-	struct regulator *reg = vreg->reg;
-	const char *name = vreg->name;
+	int ret;
 
-	BUG_ON(!vreg);
+	if (!vreg)
+		return 0;
 
-	ret = regulator_set_optimum_mode(reg, ua);
-	if (ret >= 0) {
-		/*
-		 * regulator_set_optimum_mode() returns new regulator
-		 * mode upon success.
-		 */
-		ret = 0;
-	} else {
-		dev_err(dev, "%s: %s set optimum mode(ua=%d) failed, err=%d\n",
-				__func__, name, ua, ret);
+	ret = regulator_set_load(vreg->reg, ua);
+	if (ret < 0) {
+		dev_err(dev, "%s: %s set load (ua=%d) failed, err=%d\n",
+				__func__, vreg->name, ua, ret);
 	}
 
 	return ret;
@@ -4249,18 +4277,12 @@ static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
 static inline int ufshcd_config_vreg_lpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg)
 {
-	if (!vreg)
-		return 0;
-
 	return ufshcd_config_vreg_load(hba->dev, vreg, UFS_VREG_LPM_LOAD_UA);
 }
 
 static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg)
 {
-	if (!vreg)
-		return 0;
-
 	return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA);
 }