[PATCH] pinctrl: at91: add the config GPIO_OUTPUT_x
Yang, Wenyou
Wenyou.Yang at atmel.com
Mon Mar 10 21:28:32 EDT 2014
Hi JC,
> -----Original Message-----
> From: Yang, Wenyou
> Sent: Wednesday, March 05, 2014 1:32 PM
> To: Jean-Christophe PLAGNIOL-VILLARD
> Cc: linus.walleij at linaro.org; b.brezillon at overkiz.com; <linux-arm-
> kernel at lists.infradead.org> mailing list; Linux Kernel list;
> devicetree at vger.kernel.org; robh+dt at kernel.org; pawel.moll at arm.com;
> mark.rutland at arm.com; ijc+devicetree at hellion.org.uk;
> galak at codeaurora.org
> Subject: RE: [PATCH] pinctrl: at91: add the config GPIO_OUTPUT_x
>
> Hi JC,
>
> > -----Original Message-----
> > From: Jean-Christophe PLAGNIOL-VILLARD [mailto:plagnioj at jcrosoft.com]
> > Sent: Wednesday, March 05, 2014 12:58 PM
> > To: Yang, Wenyou
> > Cc: Jean-Christophe PLAGNIOL-VILLARD; linus.walleij at linaro.org;
> > b.brezillon at overkiz.com; <linux-arm-kernel at lists.infradead.org>
> > mailing list; Linux Kernel list; devicetree at vger.kernel.org;
> > robh+dt at kernel.org; pawel.moll at arm.com; mark.rutland at arm.com;
> > ijc+devicetree at hellion.org.uk; galak at codeaurora.org
> > Subject: Re: [PATCH] pinctrl: at91: add the config GPIO_OUTPUT_x
> >
> >
> > On Mar 5, 2014, at 9:53 AM, Wenyou Yang <wenyou.yang at atmel.com> wrote:
> >
> > > In order to support the pinctrl sleep state.
> >
> > As I said before NACK
> >
> > this is not the job of the pinctrl to describe gpio output or input
> > state
> But according to what said in the section "GPIO mode pitfalls" of
> Documentation/pinctrl.txt.
> It should be handle by the pinctrl.
>
> If not, to deal with the sleep state will be very complicated.
> Muxing the pins for FUNCTION to enable peripheral, then twist them over
> to GPIO mode and use gpio_direction_output() to drive it HIGH or LOW
> during sleep.
>
> --->8 ------------
> The solution is to not think that what the datasheet calls "GPIO mode"
> has to be handled by the <linux/gpio.h> interface. Instead view this as
> a certain pin config setting. Look in e.g. <linux/pinctrl/pinconf-
> generic.h> and you find this in the documentation:
>
> PIN_CONFIG_OUTPUT: this will configure the pin in output, use argument
> 1 to indicate high level, argument 0 to indicate low level.
>
> So it is perfectly possible to push a pin into "GPIO mode" and drive the
> line low as part of the usual pin control map.
> ---<8 ------------
Do you have any feedback?
Thanks,
Wenyou Yang
>
> >
> > Best Regards,
> > J.
> > >
> > > Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
> > > ---
> > > Hi Linus,
> > >
> > > The patch is based on branch: for-next
> > > git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
> > >
> > > Best Regards,
> > > Wenyou Yang
> > >
> > > drivers/pinctrl/pinctrl-at91.c | 31
> > +++++++++++++++++++++++++++++++
> > > include/dt-bindings/pinctrl/at91.h | 2 ++
> > > 2 files changed, 33 insertions(+)
> > >
> > > diff --git a/drivers/pinctrl/pinctrl-at91.c
> > > b/drivers/pinctrl/pinctrl-at91.c index 5d24aae..fc51e59 100644
> > > --- a/drivers/pinctrl/pinctrl-at91.c
> > > +++ b/drivers/pinctrl/pinctrl-at91.c
> > > @@ -62,6 +62,8 @@ static int gpio_banks;
> > > #define DEGLITCH (1 << 2)
> > > #define PULL_DOWN (1 << 3)
> > > #define DIS_SCHMIT (1 << 4)
> > > +#define GPIO_OUTPUT_HIGH (1 << 5)
> > > +#define GPIO_OUTPUT_LOW (1 << 6)
> > > #define DEBOUNCE (1 << 16)
> > > #define DEBOUNCE_VAL_SHIFT 17
> > > #define DEBOUNCE_VAL (0x3fff << DEBOUNCE_VAL_SHIFT)
> > > @@ -152,12 +154,15 @@ struct at91_pinctrl_mux_ops {
> > > void (*set_pulldown)(void __iomem *pio, unsigned mask, bool is_on);
> > > bool (*get_schmitt_trig)(void __iomem *pio, unsigned pin);
> > > void (*disable_schmitt_trig)(void __iomem *pio, unsigned mask);
> > > + bool (*get_gpio_output)(void __iomem *pio, unsigned mask);
> > > + void (*set_gpio_output)(void __iomem *pio, unsigned mask, bool
> > > +is_high);
> > > /* irq */
> > > int (*irq_type)(struct irq_data *d, unsigned type); };
> > >
> > > static int gpio_irq_type(struct irq_data *d, unsigned type); static
> > > int alt_gpio_irq_type(struct irq_data *d, unsigned type);
> > > +static void at91_mux_gpio_enable(void __iomem *pio, unsigned mask,
> > > +bool input);
> > >
> > > struct at91_pinctrl {
> > > struct device *dev;
> > > @@ -472,6 +477,20 @@ static bool at91_mux_pio3_get_schmitt_trig(void
> > __iomem *pio, unsigned pin)
> > > return (__raw_readl(pio + PIO_SCHMITT) >> pin) & 0x1; }
> > >
> > > +static bool at91_mux_pio3_get_gpio_output(void __iomem *pio,
> > > +unsigned
> > > +pin) {
> > > + return (__raw_readl(pio + PIO_ODSR) >> pin) & 0x1; }
> > > +
> > > +static void at91_mux_pio3_set_gpio_output(void __iomem *pio,
> > > + unsigned mask,
> > > + bool is_high)
> > > +{
> > > + at91_mux_gpio_enable(pio, mask, 0);
> > > + writel_relaxed(mask, pio + (is_high ? PIO_SODR : PIO_CODR)); }
> > > +
> > > +
> > > static struct at91_pinctrl_mux_ops at91rm9200_ops = {
> > > .get_periph = at91_mux_get_periph,
> > > .mux_A_periph = at91_mux_set_A_periph,
> > > @@ -495,6 +514,8 @@ static struct at91_pinctrl_mux_ops
> > > at91sam9x5_ops
> > = {
> > > .set_pulldown = at91_mux_pio3_set_pulldown,
> > > .get_schmitt_trig = at91_mux_pio3_get_schmitt_trig,
> > > .disable_schmitt_trig = at91_mux_pio3_disable_schmitt_trig,
> > > + .get_gpio_output = at91_mux_pio3_get_gpio_output,
> > > + .set_gpio_output = at91_mux_pio3_set_gpio_output,
> > > .irq_type = alt_gpio_irq_type,
> > > };
> > >
> > > @@ -741,6 +762,10 @@ static int at91_pinconf_get(struct pinctrl_dev
> > *pctldev,
> > > *config |= PULL_DOWN;
> > > if (info->ops->get_schmitt_trig && info->ops->get_schmitt_trig(pio,
> > pin))
> > > *config |= DIS_SCHMIT;
> > > + if (info->ops->get_gpio_output) {
> > > + *config |= info->ops->get_gpio_output(pio, pin) ?
> > > + GPIO_OUTPUT_HIGH : GPIO_OUTPUT_LOW;
> > > + }
> > >
> > > return 0;
> > > }
> > > @@ -778,6 +803,12 @@ static int at91_pinconf_set(struct pinctrl_dev
> > *pctldev,
> > > info->ops->set_pulldown(pio, mask, config & PULL_DOWN);
> > > if (info->ops->disable_schmitt_trig && config & DIS_SCHMIT)
> > > info->ops->disable_schmitt_trig(pio, mask);
> > > + if (info->ops->set_gpio_output) {
> > > + if (config & GPIO_OUTPUT_HIGH)
> > > + info->ops->set_gpio_output(pio, mask, 1);
> > > + if (config & GPIO_OUTPUT_LOW)
> > > + info->ops->set_gpio_output(pio, mask, 0);
> > > + };
> > >
> > > } /* for each config */
> > >
> > > diff --git a/include/dt-bindings/pinctrl/at91.h
> > > b/include/dt-bindings/pinctrl/at91.h
> > > index 0fee6ff..e799268 100644
> > > --- a/include/dt-bindings/pinctrl/at91.h
> > > +++ b/include/dt-bindings/pinctrl/at91.h
> > > @@ -15,6 +15,8 @@
> > > #define AT91_PINCTRL_DEGLITCH (1 << 2)
> > > #define AT91_PINCTRL_PULL_DOWN (1 << 3)
> > > #define AT91_PINCTRL_DIS_SCHMIT (1 << 4)
> > > +#define AT91_PINCTRL_OUTPUT_HIGH (1 << 5)
> > > +#define AT91_PINCTRL_OUTPUT_LOW (1 << 6)
> > > #define AT91_PINCTRL_DEBOUNCE (1 << 16)
> > > #define AT91_PINCTRL_DEBOUNCE_VAL(x) (x << 17)
> > >
> > > --
> > > 1.7.9.5
> > >
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