| Message ID | 1360602659-4774-6-git-send-email-haojian.zhuang@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Feb 11, 2013 at 6:10 PM, Haojian Zhuang <haojian.zhuang@linaro.org> wrote: > Add the pl061_gpio_request() to request pinctrl. Create the logic > between pl061 gpio driver and pinctrl (pinctrl-single) driver. > > While a gpio pin is requested, it will request pinctrl driver to > set that pin with gpio function mode. So pinctrl driver should > append .gpio_request_enable() in pinmux_ops. > > Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org> (...) > +static int pl061_gpio_request(struct gpio_chip *chip, unsigned offset) > +{ > + /* > + * Map back to global GPIO space and request muxing, the direction > + * parameter does not matter for this controller. > + */ > + int gpio = chip->base + offset; > + > + return pinctrl_request_gpio(gpio); > +} So this will work find if the platform supports pinctrl, and either the pin controller can do something with this, or (after the other patch) if the GPIO is in some range, but not handled by some pin controller. But what about the case where there is a pin controller on the system, but no range matching this pin? What will happen then? Eternal deferral? Yours, Linus Walleij
On 14 February 2013 23:29, Linus Walleij <linus.walleij@linaro.org> wrote: > On Mon, Feb 11, 2013 at 6:10 PM, Haojian Zhuang > <haojian.zhuang@linaro.org> wrote: > >> Add the pl061_gpio_request() to request pinctrl. Create the logic >> between pl061 gpio driver and pinctrl (pinctrl-single) driver. >> >> While a gpio pin is requested, it will request pinctrl driver to >> set that pin with gpio function mode. So pinctrl driver should >> append .gpio_request_enable() in pinmux_ops. >> >> Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org> > (...) >> +static int pl061_gpio_request(struct gpio_chip *chip, unsigned offset) >> +{ >> + /* >> + * Map back to global GPIO space and request muxing, the direction >> + * parameter does not matter for this controller. >> + */ >> + int gpio = chip->base + offset; >> + >> + return pinctrl_request_gpio(gpio); >> +} > > So this will work find if the platform supports pinctrl, and either the > pin controller can do something with this, or (after the other patch) > if the GPIO is in some range, but not handled by some > pin controller. > > But what about the case where there is a pin controller on the > system, but no range matching this pin? > > What will happen then? Eternal deferral? > > Yours, > Linus Walleij If there's a back-end pin controller ready, but no range matching this pin, it will return 0, not error. This is the purpose that I want to add pinctrl_overlapped_gpio_range(). Yes, the name is so confusing. Let's figure out a clear name. Regards Haojian
diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c index 1a6d05c..bc9b4b2 100644 --- a/drivers/gpio/gpio-pl061.c +++ b/drivers/gpio/gpio-pl061.c @@ -23,6 +23,7 @@ #include <linux/amba/bus.h> #include <linux/amba/pl061.h> #include <linux/slab.h> +#include <linux/pinctrl/consumer.h> #include <linux/pm.h> #include <asm/mach/irq.h> @@ -61,6 +62,17 @@ struct pl061_gpio { #endif }; +static int pl061_gpio_request(struct gpio_chip *chip, unsigned offset) +{ + /* + * Map back to global GPIO space and request muxing, the direction + * parameter does not matter for this controller. + */ + int gpio = chip->base + offset; + + return pinctrl_request_gpio(gpio); +} + static int pl061_direction_input(struct gpio_chip *gc, unsigned offset) { struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc); @@ -252,6 +264,7 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id) spin_lock_init(&chip->lock); + chip->gc.request = pl061_gpio_request; chip->gc.direction_input = pl061_direction_input; chip->gc.direction_output = pl061_direction_output; chip->gc.get = pl061_get_value;
Add the pl061_gpio_request() to request pinctrl. Create the logic between pl061 gpio driver and pinctrl (pinctrl-single) driver. While a gpio pin is requested, it will request pinctrl driver to set that pin with gpio function mode. So pinctrl driver should append .gpio_request_enable() in pinmux_ops. Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org> --- drivers/gpio/gpio-pl061.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)