Currently if a regulator has "<name>-fixed-regulator"
property in device tree, it will skip current limit initialization.
This lead to a zero "max_uA" value in struct ufs_vreg.
However, "regulator_set_load" operation shall be required
on regulators which have valid current limits, otherwise a zero
"max_uA" set by "regulator_set_load" may cause unexpected behavior
when this regulator is enabled or set as high power mode.
Similarly, in device's icc_level configuration flow, the target
icc_level shall be updated if regulator also has valid current limit,
otherwise a wrong icc_level will be calculated by zero "max_uA" and
thus causes unexpected results after it is written to device.
Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Reviewed-by: Avri Altman <avri.altman@xxxxxxx>
Acked-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 81d99aebb867..5ba49c8cd2a3 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6294,19 +6294,19 @@ static u32 ufshcd_find_max_sup_active_icc_level(struct ufs_hba *hba,
goto out;
}
- if (hba->vreg_info.vcc)
+ if (hba->vreg_info.vcc && hba->vreg_info.vcc->max_uA)
icc_level = ufshcd_get_max_icc_level(
hba->vreg_info.vcc->max_uA,
POWER_DESC_MAX_ACTV_ICC_LVLS - 1,
&desc_buf[PWR_DESC_ACTIVE_LVLS_VCC_0]);
- if (hba->vreg_info.vccq)
+ if (hba->vreg_info.vccq && hba->vreg_info.vccq->max_uA)
icc_level = ufshcd_get_max_icc_level(
hba->vreg_info.vccq->max_uA,
icc_level,
&desc_buf[PWR_DESC_ACTIVE_LVLS_VCCQ_0]);
- if (hba->vreg_info.vccq2)
+ if (hba->vreg_info.vccq2 && hba->vreg_info.vccq2->max_uA)
icc_level = ufshcd_get_max_icc_level(
hba->vreg_info.vccq2->max_uA,
icc_level,
@@ -7004,6 +7004,15 @@ static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
if (!vreg)
return 0;
+ /*
+ * "set_load" operation shall be required on those regulators
+ * which specifically configured current limitation. Otherwise
+ * zero max_uA may cause unexpected behavior when regulator is
+ * enabled or set as high power mode.
+ */
+ if (!vreg->max_uA)
+ return 0;
+
ret = regulator_set_load(vreg->reg, ua);
if (ret < 0) {
dev_err(dev, "%s: %s set load (ua=%d) failed, err=%d\n",
--
2.18.0
