commit 608024a3a186c9bf958fe01dac244e187b1b04af
author Kangjie Lu <kjlu@umn.edu> Tue Dec 18 23:04:13 2018 -0600
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> Thu Dec 05 15:34:40 2019 +0100
tree a28a838a383e9e6d240e12d4bf46f2698b11999d
parent 52d915c2d4ff011ed376596ad74a15071ddb633d

drivers/regulator: fix a missing check of return value

[ Upstream commit 966e927bf8cc6a44f8b72582a1d6d3ffc73b12ad ]

If palmas_smps_read() fails, we should not use the read data in "reg"
which may contain random value. The fix inserts a check for the return
value of palmas_smps_read(): If it fails, we return the error code
upstream and stop using "reg".

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/regulator/palmas-regulator.c

diff --git a/drivers/regulator/palmas-regulator.c b/drivers/regulator/palmas-regulator.c
index f11d41d..1eb605b 100644
--- a/drivers/regulator/palmas-regulator.c
+++ b/drivers/regulator/palmas-regulator.c
@@ -435,13 +435,16 @@ static int palmas_ldo_write(struct palmas *palmas, unsigned int reg,
 static int palmas_set_mode_smps(struct regulator_dev *dev, unsigned int mode)
 {
 	int id = rdev_get_id(dev);
+	int ret;
 	struct palmas_pmic *pmic = rdev_get_drvdata(dev);
 	struct palmas_pmic_driver_data *ddata = pmic->palmas->pmic_ddata;
 	struct palmas_regs_info *rinfo = &ddata->palmas_regs_info[id];
 	unsigned int reg;
 	bool rail_enable = true;
 
-	palmas_smps_read(pmic->palmas, rinfo->ctrl_addr, &reg);
+	ret = palmas_smps_read(pmic->palmas, rinfo->ctrl_addr, &reg);
+	if (ret)
+		return ret;
 
 	reg &= ~PALMAS_SMPS12_CTRL_MODE_ACTIVE_MASK;