[PATCH] iio: maxim_thermocouple: return -EINVAL on invalid read size

[Colin King]

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

In the case that the read size is not 2 or 4 bytes
then maxim_thermocouple_read is not initializing ret and
hence may return early with a bogus error return or
just through to return with a bogos unread value in *val.
Fix this by setting ret to -EINVAL for invalid (unhandled)
read sizes.

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
 drivers/iio/temperature/maxim_thermocouple.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iio/temperature/maxim_thermocouple.c b/drivers/iio/temperature/maxim_thermocouple.c
index 066161a..f962f31 100644
--- a/drivers/iio/temperature/maxim_thermocouple.c
+++ b/drivers/iio/temperature/maxim_thermocouple.c
@@ -136,6 +136,8 @@ static int maxim_thermocouple_read(struct maxim_thermocouple_data *data,
 		ret = spi_read(data->spi, (void *)&buf32, storage_bytes);
 		*val = be32_to_cpu(buf32);
 		break;
+	default:
+		ret = -EINVAL;
 	}
 
 	if (ret)
-- 
2.9.3