Re: [PATCH v4 1/3] pinctrl: Add sleep related configuration

Rob Herring
2017-06-26T16:14:08Z

On Wed, Jun 21, 2017 at 07:55:37PM +0800, Baolin Wang wrote:
> In some scenarios, we should set some pins as input/output/pullup/pulldown
> when the specified system goes into deep sleep mode, then when the system
> goes into deep sleep mode, these pins will be set automatically by hardware.
>
> Usually we can set the "sleep" state to set sleep related config, but one SoC
> usually has not only one system (especially for mobile SoC), some systems on
> the SoC which did not run linux kernel, they can not select the "sleep" state
> when they go into deep sleep mode.

The wording here is not very clear. I think what you mean is some pins
are not controlled by any specific driver in the OS, but need to be
controlled when entering sleep mode.

> Thus we introduce some sleep related config into pinconf-generic for users to
> configure.
>
> Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
> ---
> - Add this patch since v4.
> ---
> .../bindings/pinctrl/pinctrl-bindings.txt | 12 ++++++++++++
> drivers/pinctrl/pinconf-generic.c | 10 ++++++++++
> include/linux/pinctrl/pinconf-generic.h | 14 ++++++++++++++
> 3 files changed, 36 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
> index bf3f7b0..e098059 100644
> --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
> +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
> @@ -236,6 +236,18 @@ low-power-enable - enable low power mode
> low-power-disable - disable low power mode
> output-low - set the pin to output mode with low level
> output-high - set the pin to output mode with high level
> +sleep-bias-pull-up - pull up the pin when the specified system goes into
> + deep sleep mode
> +sleep-bias-pull-down - pull down the pin when the specified system goes into
> + deep sleep mode
> +sleep-input-enable - enable input on pin when the specified system goes
> + into deep sleep mode (no effect on output)
> +sleep-intput-disable - disable input on pin when the specified system goes
> + into deep sleep mode (no effect on output)
> +sleep-output-low - set the pin to output mode with low level when the
> + specified system goes into deep sleep mode
> +sleep-output-high - set the pin to output mode with high level when the
> + specified system goes into deep sleep mode
> slew-rate - set the slew rate

I don't really like having 2 ways to define pin setup and this doesn't
scale if I need to define 3 states. Couldn't we create pin state
definitions and have a pinctrl-n property within the pin controller
node to handle all the unhandled pins?

Rob