Re: [PATCH 1/2] pinctrl: Allow a device to indicate when to force a state

[Charles Keepax]

On Wed, Sep 20, 2017 at 06:04:20PM -0700, Florian Fainelli wrote:
> It may happen that a device needs to force applying a state, e.g:
> because it only defines one state of pin states (default) but loses
> power/register contents when entering low power modes. Add a
> pinctrl_dev::flags bitmask to help describe future quirks and define
> PINCTRL_FLG_FORCE_STATE as such a settable flag.
> 
> Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
> ---
>  drivers/pinctrl/core.c | 15 +++++++++++++++
>  drivers/pinctrl/core.h |  4 ++++
>  2 files changed, 19 insertions(+)
> 
> diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
> index 56fbe4c3e800..c450a97de88f 100644
> --- a/drivers/pinctrl/core.c
> +++ b/drivers/pinctrl/core.c
> @@ -1197,11 +1197,26 @@ int pinctrl_select_state(struct pinctrl *p, struct 
> pinctrl_state *state)
>  {
>       struct pinctrl_setting *setting, *setting2;
>       struct pinctrl_state *old_state = p->state;
> +     bool force = false;
>       int ret;
>  
>       if (p->state == state)
>               return 0;

I am guessing you probably intended to remove these two lines.

>  
> +     if (p->state) {
> +             list_for_each_entry(setting, &p->state->settings, node) {
> +                     if (setting->pctldev->flags & PINCTRL_FLG_FORCE_STATE)
> +                             force = true;
> +             }
> +     }
> +
> +     /* Some controllers may want to force this operation when they define
> +      * only one set of functions and lose power state, e.g: pinctrl-single
> +      * with its pinctrl-single,low-power-state-loss property.
> +      */
> +     if (p->state == state && !force)
> +             return 0;
> +

Thanks,
Charles