From: Maxim Kiselev <bigunclemax@gmail.com> commit a8002a35935aaefcd6a42ad3289f62bab947f2ca upstream. If no n_latch value will be provided at driver probe then all pins will be used as an input: gpio->out = ~n_latch; In that case initial state for all pins is "one": gpio->status = gpio->out; So if pcf857x IRQ happens with change pin value from "zero" to "one" then we miss it, because of "one" from IRQ and "one" from initial state leaves corresponding pin unchanged: change = (gpio->status ^ status) & gpio->irq_enabled; The right solution will be to read actual state at driver probe. Cc: stable@vger.kernel.org Fixes: 6e20a0a429bd ("gpio: pcf857x: enable gpio_to_irq() support") Signed-off-by: Maxim Kiselev <bigunclemax@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/gpio/gpio-pcf857x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c index 68a35b65925ac..d3fcc0d15eb85 100644 --- a/drivers/gpio/gpio-pcf857x.c +++ b/drivers/gpio/gpio-pcf857x.c @@ -357,7 +357,7 @@ static int pcf857x_probe(struct i2c_client *client, * reset state. Otherwise it flags pins to be driven low. */ gpio->out = ~n_latch; - gpio->status = gpio->out; + gpio->status = gpio->read(gpio->client); status = devm_gpiochip_add_data(&client->dev, &gpio->chip, gpio); if (status < 0) -- 2.25.1