Re: [PATCH v2 4/4] Input: sun4i-ps2 - Fix handling of platform_get_irq() error

From: Krzysztof Kozlowski <krzk@kernel.org>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Maxime Ripard <mripard@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
	linux-input@vger.kernel.org,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 4/4] Input: sun4i-ps2 - Fix handling of platform_get_irq() error
Date: Wed, 16 Sep 2020 08:08:36 +0200	[thread overview]
Message-ID: <CAJKOXPesf1mnt_QC59Bgt27r4Ntu4vowBQCvexmRkASVhuPLEw@mail.gmail.com> (raw)
In-Reply-To: <20200916010140.GG1681290@dtor-ws>

On Wed, 16 Sep 2020 at 03:01, Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
>
> On Fri, Aug 28, 2020 at 04:57:44PM +0200, Krzysztof Kozlowski wrote:
> > platform_get_irq() returns -ERRNO on error.  In such case comparison
> > to 0 would pass the check.
> >
> > Fixes: e443631d20f5 ("Input: serio - add support for Alwinner A10/A20 PS/2 controller")
> > Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
> >
> > ---
> >
> > Changes since v1:
> > 1. None
> > ---
> >  drivers/input/serio/sun4i-ps2.c | 5 ++---
> >  1 file changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/input/serio/sun4i-ps2.c b/drivers/input/serio/sun4i-ps2.c
> > index a681a2c04e39..7da1ea8741fc 100644
> > --- a/drivers/input/serio/sun4i-ps2.c
> > +++ b/drivers/input/serio/sun4i-ps2.c
> > @@ -265,9 +265,8 @@ static int sun4i_ps2_probe(struct platform_device *pdev)
> >
> >       /* Get IRQ for the device */
> >       irq = platform_get_irq(pdev, 0);
> > -     if (!irq) {
> > -             dev_err(dev, "no IRQ found\n");
> > -             error = -ENXIO;
> > +     if (irq < 0) {
>
> "irq" is unsigned here, so this will not work. I'll change it to use
> drvdat->irq which happens to be signed, and drop "irq" variable.

Yes, thanks. I wonder now why there was no warning of unsigned<0 comparison.

Best regards,
Krzysztof