Input: resistive-adc-touch - fix uninitialized variable 'press'
authorColin Ian King <colin.king@canonical.com>
Sat, 5 Jun 2021 23:09:36 +0000 (16:09 -0700)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Sat, 5 Jun 2021 23:41:08 +0000 (16:41 -0700)
In the case where st->ch_map[GRTS_CH_PRESSURE] < GRTS_MAX_CHANNELS is false
and also st->ch_map[GRTS_CH_Z1] < GRTS_MAX_CHANNELS is false the variable
press is not initialized and contains garbage. In this situation
st->pressure is also false, so we do not actually use press value, but
it is impossible for the compiler to realize this, and it emits
"uninitialized variable" warning. Fix this by initializing press
to 0 and allows us to also remove an else clause that sets press to 0.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: 60b7db914ddd ("Input: resistive-adc-touch - rework mapping of channels")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210603220809.155118-1-colin.king@canonical.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
drivers/input/touchscreen/resistive-adc-touch.c

index ea7dd9d2b2acb9a5a84b4fdae8593b9041843d2b..744544a723b7748510605329e24910bf42ecc275 100644 (file)
@@ -59,7 +59,7 @@ static int grts_cb(const void *data, void *private)
 {
        const u16 *touch_info = data;
        struct grts_state *st = private;
-       unsigned int x, y, press;
+       unsigned int x, y, press = 0;
 
        x = touch_info[st->ch_map[GRTS_CH_X]];
        y = touch_info[st->ch_map[GRTS_CH_Y]];
@@ -84,8 +84,6 @@ static int grts_cb(const void *data, void *private)
                 */
                if (Rt < GRTS_DEFAULT_PRESSURE_MAX)
                        press = GRTS_DEFAULT_PRESSURE_MAX - Rt;
-               else
-                       press = 0;
        }
 
        if ((!x && !y) || (st->pressure && (press < st->pressure_min))) {