From mboxrd@z Thu Jan 1 00:00:00 1970 From: acourbot@nvidia.com (Alex Courbot) Date: Wed, 11 Sep 2013 10:58:00 +0900 Subject: [PATCH 3/7] misc: ixp4-beeper: use gpiolib strictly In-Reply-To: <1378816226-8016-1-git-send-email-linus.walleij@linaro.org> References: <1378816226-8016-1-git-send-email-linus.walleij@linaro.org> Message-ID: <522FCE28.8020909@nvidia.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 09/10/2013 09:30 PM, Linus Walleij wrote: > Request and free the GPIO line used for the beeper properly. > Then use the gpiolib API to flip the output of the GPIO pin > instead of relying on hacks to poke the register bits. > > Cc: Imre Kaloz > Cc: Krzysztof Halasa > Cc: Alexandre Courbot > Cc: Arnd Bergmann > Cc: Greg Kroah-Hartman > Signed-off-by: Linus Walleij > --- > Arnd/Greg: seeking your ACK to take this through the GPIO tree > as part of the attempt at cleaning out custom GPIO implementations. > --- > drivers/input/misc/ixp4xx-beeper.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/drivers/input/misc/ixp4xx-beeper.c b/drivers/input/misc/ixp4xx-beeper.c > index f14afd0..fb3bec5 100644 > --- a/drivers/input/misc/ixp4xx-beeper.c > +++ b/drivers/input/misc/ixp4xx-beeper.c > @@ -76,11 +76,13 @@ static int ixp4xx_spkr_event(struct input_dev *dev, unsigned int type, unsigned > > static irqreturn_t ixp4xx_spkr_interrupt(int irq, void *dev_id) > { > + unsigned int pin = (unsigned int) dev_id; > + > /* clear interrupt */ > *IXP4XX_OSST = IXP4XX_OSST_TIMER_2_PEND; > > /* flip the beeper output */ > - *IXP4XX_GPIO_GPOUTR ^= (1 << (unsigned int) dev_id); > + gpio_set_value(pin, ~gpio_get_value(pin)); Don't you want gpio_set_value(pin, !gpio_get_value(pin)); instead? From the deleted line I suppose you guess to invert the GPIO value, but using ~ will invert all the bits of the integer returned by gpio_get_value(), meaning that if it returns 1 you will end up calling gpio_set_value(-2). In practice your gpio is very unlikely to ever be set to 0. > > return IRQ_HANDLED; > } > @@ -108,11 +110,15 @@ static int ixp4xx_spkr_probe(struct platform_device *dev) > input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE); > input_dev->event = ixp4xx_spkr_event; > > + err = gpio_request(dev->id, "ixp4-beeper"); > + if (err) > + goto err_free_device; > + > err = request_irq(IRQ_IXP4XX_TIMER2, &ixp4xx_spkr_interrupt, > IRQF_NO_SUSPEND, "ixp4xx-beeper", > (void *) dev->id); > if (err) > - goto err_free_device; > + goto err_free_gpio; > > err = input_register_device(input_dev); > if (err) > @@ -124,6 +130,8 @@ static int ixp4xx_spkr_probe(struct platform_device *dev) > > err_free_irq: > free_irq(IRQ_IXP4XX_TIMER2, (void *)dev->id); > + err_free_gpio: > + gpio_free(dev->id); > err_free_device: > input_free_device(input_dev); > > @@ -142,6 +150,7 @@ static int ixp4xx_spkr_remove(struct platform_device *dev) > ixp4xx_spkr_control(pin, 0); > > free_irq(IRQ_IXP4XX_TIMER2, (void *)dev->id); > + gpio_free(dev->id); Just wondering, is there a reason for not using the devm_gpio functions here? > > return 0; > } >