iio: tsl4531: fix error handling in tsl4531_check_id()

The tsl4531_check_id() function returned 1 on "found" and 0 on "not
found" and negative error codes on failure.  This was non-standard and
bug prone.  The caller treated all non-zero values including error codes
as "found".

This patch fixes it by changing the tsl4531_check_id() to return zero on
success or a negative error code, and updates the caller.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/light/tsl4531.c b/drivers/iio/light/tsl4531.c
index 2697918..cf94ec7 100644 (file)
--- a/drivers/iio/light/tsl4531.c
+++ b/drivers/iio/light/tsl4531.c
@@ -158,9 +158,9 @@ static int tsl4531_check_id(struct i2c_client *client)
        case TSL45313_ID:
        case TSL45315_ID:
        case TSL45317_ID:
-               return 1;
-       default:
                return 0;
+       default:
+               return -ENODEV;
        }
 }
 
@@ -180,9 +180,10 @@ static int tsl4531_probe(struct i2c_client *client,
        data->client = client;
        mutex_init(&data->lock);
 
-       if (!tsl4531_check_id(client)) {
+       ret = tsl4531_check_id(client);
+       if (ret) {
                dev_err(&client->dev, "no TSL4531 sensor\n");
-               return -ENODEV;
+               return ret;
        }
 
        ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONTROL,