[PATCH v2] iio: hmc5843: fix potential NULL pointer dereferences

[Kangjie Lu]

devm_regmap_init_i2c may fail and return NULL. The fix returns
the error when it fails.

Signed-off-by: Kangjie Lu <k...@umn.edu>
---
V2: fix the two together
---
 drivers/iio/magnetometer/hmc5843_i2c.c | 7 ++++++-
 drivers/iio/magnetometer/hmc5843_spi.c | 7 ++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/magnetometer/hmc5843_i2c.c 
b/drivers/iio/magnetometer/hmc5843_i2c.c
index 3de7f4426ac4..86abba5827a2 100644
--- a/drivers/iio/magnetometer/hmc5843_i2c.c
+++ b/drivers/iio/magnetometer/hmc5843_i2c.c
@@ -58,8 +58,13 @@ static const struct regmap_config hmc5843_i2c_regmap_config 
= {
 static int hmc5843_i2c_probe(struct i2c_client *cli,
                             const struct i2c_device_id *id)
 {
+       struct regmap *regmap = devm_regmap_init_i2c(cli,
+                       &hmc5843_i2c_regmap_config);
+       if (IS_ERR(regmap))
+               return PTR_ERR(regmap);
+
        return hmc5843_common_probe(&cli->dev,
-                       devm_regmap_init_i2c(cli, &hmc5843_i2c_regmap_config),
+                       regmap,
                        id->driver_data, id->name);
 }
 
diff --git a/drivers/iio/magnetometer/hmc5843_spi.c 
b/drivers/iio/magnetometer/hmc5843_spi.c
index 535f03a70d63..8355713651d4 100644
--- a/drivers/iio/magnetometer/hmc5843_spi.c
+++ b/drivers/iio/magnetometer/hmc5843_spi.c
@@ -58,6 +58,7 @@ static const struct regmap_config hmc5843_spi_regmap_config = 
{
 static int hmc5843_spi_probe(struct spi_device *spi)
 {
        int ret;
+       struct regmap *regmap;
        const struct spi_device_id *id = spi_get_device_id(spi);
 
        spi->mode = SPI_MODE_3;
@@ -67,8 +68,12 @@ static int hmc5843_spi_probe(struct spi_device *spi)
        if (ret)
                return ret;
 
+       regmap = devm_regmap_init(spi, &hmc5843_spi_regmap_config);
+       if (IS_ERR(regmap))
+               return PTR_ERR(devm_regmap);
+
        return hmc5843_common_probe(&spi->dev,
-                       devm_regmap_init_spi(spi, &hmc5843_spi_regmap_config),
+                       regmap,
                        id->driver_data, id->name);
 }
 
-- 
2.17.1