Re: [PATCH RESEND] gpio: add flags to export GPIOs when requesting

From: Grant Likely
Date: Mon Jan 16 2012 - 11:32:00 EST


On Fri, Jan 06, 2012 at 04:27:41PM +0100, Wolfram Sang wrote:
> On Tue, Dec 13, 2011 at 06:34:01PM +0100, Wolfram Sang wrote:
> > Introduce new flags to automatically export GPIOs when using the convenience
> > functions gpio_request_one() or gpio_request_array(). This eases support for
> > custom boards where lots of GPIOs need to be exported for customer
> > applications.
> >
> > Signed-off-by: Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
> > ---
> >
> > Based on 3.2-rc5. Previous discussion (with kind of acks) can be found here
> >
> > http://lkml.org/lkml/2011/11/15/378
>
> Ping. I am using this patch with v3.2 right now and it is really useful
> (and no build failure this time (I owe you a drink for my last patch!))

Applied, thanks.

g.

>
> >
> > Documentation/gpio.txt | 3 +++
> > drivers/gpio/gpiolib.c | 12 +++++++++++-
> > include/linux/gpio.h | 5 +++++
> > 3 files changed, 19 insertions(+), 1 deletions(-)
> >
> > diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt
> > index 792faa3..9e28c05 100644
> > --- a/Documentation/gpio.txt
> > +++ b/Documentation/gpio.txt
> > @@ -303,6 +303,9 @@ where 'flags' is currently defined to specify the following properties:
> > * GPIOF_INIT_LOW - as output, set initial level to LOW
> > * GPIOF_INIT_HIGH - as output, set initial level to HIGH
> >
> > + * GPIOF_EXPORT_DIR_FIXED - export gpio to sysfs, keep direction
> > + * GPIOF_EXPORT_DIR_CHANGEABLE - also export, allow changing direction
> > +
> > since GPIOF_INIT_* are only valid when configured as output, so group valid
> > combinations as:
> >
> > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> > index a971e3d..65ba047 100644
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -1285,8 +1285,18 @@ int gpio_request_one(unsigned gpio, unsigned long flags, const char *label)
> > (flags & GPIOF_INIT_HIGH) ? 1 : 0);
> >
> > if (err)
> > - gpio_free(gpio);
> > + goto free_gpio;
> > +
> > + if (flags & GPIOF_EXPORT) {
> > + err = gpio_export(gpio, flags & GPIOF_EXPORT_CHANGEABLE);
> > + if (err)
> > + goto free_gpio;
> > + }
> > +
> > + return 0;
> >
> > + free_gpio:
> > + gpio_free(gpio);
> > return err;
> > }
> > EXPORT_SYMBOL_GPL(gpio_request_one);
> > diff --git a/include/linux/gpio.h b/include/linux/gpio.h
> > index 38ac48b..38afe24 100644
> > --- a/include/linux/gpio.h
> > +++ b/include/linux/gpio.h
> > @@ -14,6 +14,11 @@
> > #define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW)
> > #define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
> >
> > +#define GPIOF_EXPORT (1 << 2)
> > +#define GPIOF_EXPORT_CHANGEABLE (1 << 3)
> > +#define GPIOF_EXPORT_DIR_FIXED (GPIOF_EXPORT)
> > +#define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
> > +
> > /**
> > * struct gpio - a structure describing a GPIO with configuration
> > * @gpio: the GPIO number
> > --
> > 1.7.2.5
> >
>
> --
> Pengutronix e.K. | Wolfram Sang |
> Industrial Linux Solutions | http://www.pengutronix.de/ |


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/