iio: meter: ade7759: add error handling in _reset and _stop_device

This patch adds the error handling for the value returned from
ade7759_spi_read_reg_16. With this patch, the following randconfig
warnings get fixed automatically.

drivers/staging/iio/meter/ade7759.c:224:6: warning: ‘val’ may be
used uninitialized in this function [-Wmaybe-uninitialized]
drivers/staging/iio/meter/ade7759.c:309:6: warning: ‘val’ may be
used uninitialized in this function [-Wmaybe-uninitialized]

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/meter/ade7759.c b/drivers/staging/iio/meter/ade7759.c
index b0c7dbc..9afdb1e 100644 (file)
--- a/drivers/staging/iio/meter/ade7759.c
+++ b/drivers/staging/iio/meter/ade7759.c
@@ -218,9 +218,12 @@ static int ade7759_reset(struct device *dev)
        int ret;
        u16 val;
 
-       ade7759_spi_read_reg_16(dev,
+       ret = ade7759_spi_read_reg_16(dev,
                        ADE7759_MODE,
                        &val);
+       if (ret < 0)
+               return ret;
+
        val |= 1 << 6; /* Software Chip Reset */
        ret = ade7759_spi_write_reg_16(dev,
                        ADE7759_MODE,
@@ -301,11 +304,18 @@ error_ret:
 /* Power down the device */
 static int ade7759_stop_device(struct device *dev)
 {
+       int ret;
        u16 val;
 
-       ade7759_spi_read_reg_16(dev,
+       ret = ade7759_spi_read_reg_16(dev,
                        ADE7759_MODE,
                        &val);
+       if (ret < 0) {
+               dev_err(dev, "unable to power down the device, error: %d\n",
+                       ret);
+               return ret;
+       }
+
        val |= 1 << 4;  /* AD converters can be turned off */
 
        return ade7759_spi_write_reg_16(dev, ADE7759_MODE, val);