While playing with audio output on Meson8b I found out that the
vendor kernel uses a custom version of the GPIO_PULL_UP flag. I
suspect that we will need this for audio support on Meson8b and/or
Meson8m2 but I don't see it hurt other platforms.
Also while comparing the register bits with the GPIO direction (of
GPIOs exported to sysfs) I sometimes had a mismatch. This also wires
up gpio_chip.get_direction to have sysfs and the actual registers in
sync.
Martin Blumenstingl (2):
pinctrl: meson: implement the gpio_chip get_direction callback
pinctrl: meson: wire up the gpio_chip's set_config callback
drivers/pinctrl/meson/pinctrl-meson.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
--
2.26.0
Use gpiochip_generic_config for the gpio_chip's set_config callback so
GPIO flags like GPIO_PULL_UP or GPIO_PULL_DOWN can be used in the board
.dts descriptions.
This is required for some Meson8m2 boards where GPIO_BSD_EN provides the
"MUTE" signal and requires enabling the internal pull-up resistor.
Signed-off-by: Martin Blumenstingl <[email protected]>
---
drivers/pinctrl/meson/pinctrl-meson.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/pinctrl/meson/pinctrl-meson.c b/drivers/pinctrl/meson/pinctrl-meson.c
index 291f3078e7c7..079f8ee8d353 100644
--- a/drivers/pinctrl/meson/pinctrl-meson.c
+++ b/drivers/pinctrl/meson/pinctrl-meson.c
@@ -603,6 +603,7 @@ static int meson_gpiolib_register(struct meson_pinctrl *pc)
pc->chip.parent = pc->dev;
pc->chip.request = gpiochip_generic_request;
pc->chip.free = gpiochip_generic_free;
+ pc->chip.set_config = gpiochip_generic_config;
pc->chip.get_direction = meson_gpio_get_direction;
pc->chip.direction_input = meson_gpio_direction_input;
pc->chip.direction_output = meson_gpio_direction_output;
--
2.26.0
On Sat 11 Apr 2020 at 19:03, Martin Blumenstingl <[email protected]> wrote:
> Use gpiochip_generic_config for the gpio_chip's set_config callback so
> GPIO flags like GPIO_PULL_UP or GPIO_PULL_DOWN can be used in the board
> .dts descriptions.
> This is required for some Meson8m2 boards where GPIO_BSD_EN provides the
> "MUTE" signal and requires enabling the internal pull-up resistor.
I think your addition makes sense but, FYI, there is another solution to
your problem that should already work as it is.
If the platform requires a pull-up, you could set the pinconf 'bias-pull-up'
property in dt in the pinctrl definition passed to the device using the gpio.
There is an example of that in meson-gx-libretech-pc.dtsi with the phy
irq pin.
>
> Signed-off-by: Martin Blumenstingl <[email protected]>
> ---
> drivers/pinctrl/meson/pinctrl-meson.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/pinctrl/meson/pinctrl-meson.c b/drivers/pinctrl/meson/pinctrl-meson.c
> index 291f3078e7c7..079f8ee8d353 100644
> --- a/drivers/pinctrl/meson/pinctrl-meson.c
> +++ b/drivers/pinctrl/meson/pinctrl-meson.c
> @@ -603,6 +603,7 @@ static int meson_gpiolib_register(struct meson_pinctrl *pc)
> pc->chip.parent = pc->dev;
> pc->chip.request = gpiochip_generic_request;
> pc->chip.free = gpiochip_generic_free;
> + pc->chip.set_config = gpiochip_generic_config;
> pc->chip.get_direction = meson_gpio_get_direction;
> pc->chip.direction_input = meson_gpio_direction_input;
> pc->chip.direction_output = meson_gpio_direction_output;
Hi Jerome,
On Sat, Apr 11, 2020 at 7:23 PM Jerome Brunet <[email protected]> wrote:
>
>
> On Sat 11 Apr 2020 at 19:03, Martin Blumenstingl <[email protected]> wrote:
>
> > Use gpiochip_generic_config for the gpio_chip's set_config callback so
> > GPIO flags like GPIO_PULL_UP or GPIO_PULL_DOWN can be used in the board
> > .dts descriptions.
> > This is required for some Meson8m2 boards where GPIO_BSD_EN provides the
> > "MUTE" signal and requires enabling the internal pull-up resistor.
>
> I think your addition makes sense but, FYI, there is another solution to
> your problem that should already work as it is.
>
> If the platform requires a pull-up, you could set the pinconf 'bias-pull-up'
> property in dt in the pinctrl definition passed to the device using the gpio.
Thank you for this hint.
personally I find GPIO_PULL_UP is easier to write when I'm passing a
GPIO descriptor anyways.
> There is an example of that in meson-gx-libretech-pc.dtsi with the phy
> irq pin.
I'm still hoping that pinctrl-meson will gain interrupt support one
day, then the driver will (hopefully) take care of that :-)
Martin
On Sat 11 Apr 2020 at 22:53, Martin Blumenstingl <[email protected]> wrote:
>
>> There is an example of that in meson-gx-libretech-pc.dtsi with the phy
>> irq pin.
> I'm still hoping that pinctrl-meson will gain interrupt support one
> day, then the driver will (hopefully) take care of that :-)
I don't see why it should. If the meson gpio driver was able to provide
an irq related to gpio, I don't think it should do more than that.
In most case the gpio will be an input, yes, but nothing says it must.
>
>
> Martin