iio: tsl2583: Fix division by a zero lux_val

commit af0e1871d79cfbb91f732d2c6fa7558e45c31038 upstream.

The lux_val returned from tsl2583_get_lux can potentially be zero,
so check for this to avoid a division by zero and an overflowed
gain_trim_val.

Fixes clang scan-build warning:

drivers/iio/light/tsl2583.c:345:40: warning: Either the
condition 'lux_val<0' is redundant or there is division
by zero at line 345. [zerodivcond]

Fixes: ac4f6eee8fe8 ("staging: iio: TAOS tsl258x: Device driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[iwamatsu: Change file path.]
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/iio/light/tsl2583.c b/drivers/staging/iio/light/tsl2583.c
index 3100d960fe2c6dc57a49361dcbd5ce53c00e9ef0..da2a2ff4cdb99804631e28040300ae83744e4aba 100644 (file)
--- a/drivers/staging/iio/light/tsl2583.c
+++ b/drivers/staging/iio/light/tsl2583.c
@@ -378,6 +378,15 @@ static int taos_als_calibrate(struct iio_dev *indio_dev)
                dev_err(&chip->client->dev, "taos_als_calibrate failed to get lux\n");
                return lux_val;
        }
+
+       /* Avoid division by zero of lux_value later on */
+       if (lux_val == 0) {
+               dev_err(&chip->client->dev,
+                       "%s: lux_val of 0 will produce out of range trim_value\n",
+                       __func__);
+               return -ENODATA;
+       }
+
        gain_trim_val = (unsigned int) (((chip->taos_settings.als_cal_target)
                        * chip->taos_settings.als_gain_trim) / lux_val);