| Message ID | CALHCpMg7-OHSiBHOObUSTtH6gSLhg9yfh9u=E6tGnTLbhJVucw@mail.gmail.com |
|---|---|
| State | Accepted |
| Commit | a8002a35935aaefcd6a42ad3289f62bab947f2ca |
| Headers | show |
| Series | gpio: pcf857x: Fix missing first interrupt | expand |
On Tue, Feb 16, 2021 at 9:16 PM Maksim Kiselev <bigunclemax@gmail.com> wrote: > > From: Maxim Kiselev <bigunclemax@gmail.com> > Date: Tue, 16 Feb 2021 17:00:58 +0300 > Subject: [PATCH] gpio: pcf857x: Fix missing first interrupt > > 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. > > Fixies: commit 6e20a0a429bd ("gpio: pcf857x: enable gpio_to_irq() support") > Signed-off-by: Maxim Kiselev <bigunclemax@gmail.com> > --- > 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 a2a8d155c75e3..b7568ee33696d 100644 > --- a/drivers/gpio/gpio-pcf857x.c > +++ b/drivers/gpio/gpio-pcf857x.c > @@ -332,7 +332,7 @@ 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); > /* Enable irqchip if we have an interrupt */ > if (client->irq) { > -- > 2.27.0 Applied with the Fixes tag fixed. Bartosz
diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c index a2a8d155c75e3..b7568ee33696d 100644 --- a/drivers/gpio/gpio-pcf857x.c +++ b/drivers/gpio/gpio-pcf857x.c @@ -332,7 +332,7 @@ 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); /* Enable irqchip if we have an interrupt */ if (client->irq) { -- 2.27.0