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[v3,2/5] scsi: ufs: Avoid configuring undefined voltage range on a regulator

Message ID 1552875280-16196-4-git-send-email-stanley.chu@mediatek.com (mailing list archive)
State New, archived
Headers show
Series [v3,1/5] scsi: ufs: Remove unused min_uA field in struct ufs_vreg | expand

Commit Message

Stanley Chu March 18, 2019, 2:14 a.m. UTC
For regulators used by UFS, vcc, vccq and vccq2 will have voltage range
initialized by ufshcd_populate_vreg(), however other regulators may
not have voltage range settings if undefined in dt-bindings.

In this case, both "min_uV" and "max_uV" fields in ufs_vreg struct
will be zero values and used as new voltage range for voltage
configuration in different power modes.

Currently this may have no harm because if both "min_uV" and "max_uV"
always keep "zero value", regulator_set_voltage() will always bypass
such invalid values and return "good" results.

However improper values shall be fixed to avoid future potential
bug. Simply bypass voltage configuration if voltage range is not
defined.

Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
---
 drivers/scsi/ufs/ufshcd.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 8b9a01073d62..4e41fdfd0e53 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7024,12 +7024,15 @@  static int ufshcd_config_vreg(struct device *dev,
 	name = vreg->name;
 
 	if (regulator_count_voltages(reg) > 0) {
-		min_uV = on ? vreg->min_uV : 0;
-		ret = regulator_set_voltage(reg, min_uV, vreg->max_uV);
-		if (ret) {
-			dev_err(dev, "%s: %s set voltage failed, err=%d\n",
+		if (vreg->min_uV && vreg->max_uV) {
+			min_uV = on ? vreg->min_uV : 0;
+			ret = regulator_set_voltage(reg, min_uV, vreg->max_uV);
+			if (ret) {
+				dev_err(dev,
+					"%s: %s set voltage failed, err=%d\n",
 					__func__, name, ret);
-			goto out;
+				goto out;
+			}
 		}
 
 		uA_load = on ? vreg->max_uA : 0;