[PATCH v1 2/6] scsi: ufs: set load before setting voltage in regulators

Can Guo
2019-11-07T08:42:48Z

From: Asutosh Das <asutoshd@codeaurora.org>

This sequence change is required to avoid dips in voltage
during boot-up.

Apparently, this dip is caused because in the original
sequence, the regulators are initialized in lpm mode.
And then when the load is set to high, and more current
is drawn, than is allowed in lpm, the dip is seen.

Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
---
drivers/scsi/ufs/ufshcd.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c2de29f..c386c2d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7225,6 +7225,11 @@ static int ufshcd_config_vreg(struct device *dev,
name = vreg->name;

if (regulator_count_voltages(reg) > 0) {
+ uA_load = on ? vreg->max_uA : 0;
+ ret = ufshcd_config_vreg_load(dev, vreg, uA_load);
+ if (ret)
+ goto out;
+
if (vreg->min_uV && vreg->max_uV) {
min_uV = on ? vreg->min_uV : 0;
ret = regulator_set_voltage(reg, min_uV, vreg->max_uV);
@@ -7235,11 +7240,6 @@ static int ufshcd_config_vreg(struct device *dev,
goto out;
}
}
-
- uA_load = on ? vreg->max_uA : 0;
- ret = ufshcd_config_vreg_load(dev, vreg, uA_load);
- if (ret)
- goto out;
}
out:
return ret;