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path: root/drivers/scsi/ufs/ufshcd.c
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Diffstat (limited to 'drivers/scsi/ufs/ufshcd.c')
-rw-r--r--drivers/scsi/ufs/ufshcd.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 2aa85e398f76..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;