staging: iio: adc: ad799x: Address iio list feedback

Address feedback from Shubhrajyoti Datta:
	Cast return value
Michael Hennerich:
	Use i2c_smbus_read_byte_data()
	Fix return value check

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 5 insertions, 6 deletions

diff --git a/drivers/staging/iio/adc/ad799x_core.c b/drivers/staging/iio/adc/ad799x_core.c
index dca3f2ae6a14..25898563aae8 100644
--- a/drivers/staging/iio/adc/ad799x_core.c
+++ b/drivers/staging/iio/adc/ad799x_core.c
@@ -65,13 +65,13 @@ static int ad799x_i2c_read8(struct ad799x_state *st, u8 reg, u8 *data)
         struct i2c_client *client = st->client;
         int ret = 0;
 
-        ret = i2c_smbus_read_word_data(client, reg);
+        ret = i2c_smbus_read_byte_data(client, reg);
         if (ret < 0) {
                 dev_err(&client->dev, "I2C read error\n");
                 return ret;
         }
 
-        *data = ret;
+        *data = (u8)ret;
 
         return 0;
 }
@@ -182,11 +182,10 @@ static ssize_t ad799x_read_single_channel(struct device *dev,
         mask = 1 << this_attr->address;
         /* If ring buffer capture is occuring, query the buffer */
         if (iio_ring_enabled(dev_info)) {
-                data = ad799x_single_channel_from_ring(st, mask);
-                if (data < 0) {
-                        ret = data;
+                data = ret = ad799x_single_channel_from_ring(st, mask);
+                if (ret < 0)
                         goto error_ret;
-                }
+                ret = 0;
         } else {
                 switch (st->id) {
                 case ad7991: