From: Zhe Wang <zhe.wang1@xxxxxxxxxx>
Some UFS devices require that the VCC should drop below 0.1V after
turning off, otherwise device may not resume successfully. And
because the power-off rate is different on different SOC platforms.
Therefore, we hope that the delay can be modified by vendor to
adjust the most appropriate delay value.
Signed-off-by: Zhe Wang <zhe.wang1@xxxxxxxxxx>
---
V1 -> V2
- move turnoff_delay_us to struct ufs_vreg instead
- replace usleep_range with ufshcd_delay_us
drivers/ufs/core/ufshcd.c | 9 ++++++++-
include/ufs/ufs.h | 1 +
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 7256e6c43ca6..386ff6ed2f20 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -89,6 +89,9 @@
/* Polling time to wait for fDeviceInit */
#define FDEVICEINIT_COMPL_TIMEOUT 1500 /* millisecs */
+/* Default value of turn off VCC rail: 5000us */
+#define UFS_VCC_TURNOFF_DELAY_US 5000
+
#define ufshcd_toggle_vreg(_dev, _vreg, _on) \
({ \
int _ret; \
@@ -7784,6 +7787,10 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
ufs_fixup_device_setup(hba);
+ if (hba->dev_quirks & UFS_DEVICE_QUIRK_DELAY_AFTER_LPM &&
+ !hba->vreg_info.vcc->turnoff_delay_us)
+ hba->vreg_info.vcc->turnoff_delay_us = UFS_VCC_TURNOFF_DELAY_US;
+
ufshcd_wb_probe(hba, desc_buf);
ufshcd_temp_notif_probe(hba, desc_buf);
@@ -8918,7 +8925,7 @@ static void ufshcd_vreg_set_lpm(struct ufs_hba *hba)
*/
if (vcc_off && hba->vreg_info.vcc &&
hba->dev_quirks & UFS_DEVICE_QUIRK_DELAY_AFTER_LPM)
- usleep_range(5000, 5100);
+ ufshcd_delay_us(hba->vreg_info.vcc->turnoff_delay_us, 100);
}
#ifdef CONFIG_PM
diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
index 1bba3fead2ce..792335dfd70b 100644
--- a/include/ufs/ufs.h
+++ b/include/ufs/ufs.h
@@ -569,6 +569,7 @@ struct ufs_vreg {
bool always_on;
bool enabled;
int max_uA;
+ u32 turnoff_delay_us;
};
struct ufs_vreg_info {
--
2.17.1
