Re: [PATCH] platform/x86: barco-p50-gpio: normalize return value of gpio_get

[Ilpo Järvinen]

On Mon, 9 Mar 2026, Dmitry Torokhov wrote:

> On Mon, Feb 23, 2026 at 04:11:10PM +0200, Ilpo Järvinen wrote:
> > On Wed, 18 Feb 2026, Dmitry Torokhov wrote:
> > 
> > > The GPIO get callback is expected to return 0 or 1 (or a negative error
> > > code). Ensure that the value returned by p50_gpio_get() is normalized
> > > to the [0, 1] range.
> > > 
> > > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> > > ---
> > >  drivers/platform/x86/barco-p50-gpio.c | 5 ++++-
> > >  1 file changed, 4 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/platform/x86/barco-p50-gpio.c b/drivers/platform/x86/barco-p50-gpio.c
> > > index 6f13e81f98fb..360ffd8505d6 100644
> > > --- a/drivers/platform/x86/barco-p50-gpio.c
> > > +++ b/drivers/platform/x86/barco-p50-gpio.c
> > > @@ -275,8 +275,11 @@ static int p50_gpio_get(struct gpio_chip *gc, unsigned int offset)
> > >  	mutex_lock(&p50->lock);
> > >  
> > >  	ret = p50_send_mbox_cmd(p50, P50_MBOX_CMD_READ_GPIO, gpio_params[offset], 0);
> > > -	if (ret == 0)
> > > +	if (ret == 0) {
> > >  		ret = p50_read_mbox_reg(p50, P50_MBOX_REG_DATA);
> > > +		if (ret >= 0)
> > > +			ret = !!ret;
> > > +	}
> > >  
> > >  	mutex_unlock(&p50->lock);
> > 
> > A simpler flow would be preferrable over all that nesting. Is this 
> > logically correct:
> > 
> > 	guard(mutex)(p50->lock);
> > 	ret = p50_send_mbox_cmd(p50, P50_MBOX_CMD_READ_GPIO, gpio_params[offset], 0);
> > 	if (ret < 0)
> > 		return ret;
> > 
> > 	ret = p50_read_mbox_reg(p50, P50_MBOX_REG_DATA);
> > 	if (ret < 0)
> > 		return ret;
> > 
> > 	return !!ret;
> 
> Yes, but I wanted to minimize the amount of change. Maybe I should send
> a followup patch converting to guard()?

Please do. I don't want to be adding into complexity when we've a nice 
solution to simplify it using guard().

-- 
 i.