When the input key number is not valid one of '/sys/devices/soc0/gpio-keys/keys', need to report an error, but not continue. See the following example: root@yocto:/sys/devices/soc0/gpio-keys# cat keys 114-116 root@yocto:/sys/devices/soc0/gpio-keys# echo 77 > keys root@yocto:/sys/devices/soc0/gpio-keys# we want 'echo 77 > keys' to report an error, but not silence to give us an fake illusion that all is 'ok'. Signed-off-by: Peng Fan <van.freenix@xxxxxxxxx> Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx> Cc: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx> Cc: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx> --- drivers/input/keyboard/gpio_keys.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index ddf4045..b98f3b4 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -239,6 +239,11 @@ static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, } } + if (i == ddata->pdata->nbuttons) { + error = -EINVAL; + goto out; + } + mutex_lock(&ddata->disable_lock); for (i = 0; i < ddata->pdata->nbuttons; i++) { -- 1.8.4.5 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html