Hi Shimoda-san,
On Mon, Jul 8, 2019 at 11:08 AM Yoshihiro Shimoda
<yoshihiro.shimoda.uh@xxxxxxxxxxx> wrote:
> R-Car PWM controller requires the gpio to output zero duty,
> this patch allows to roll it back from gpio to mux when the gpio
> is freed.
>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Thanks for your patch!
> --- a/drivers/pinctrl/sh-pfc/pinctrl.c
> +++ b/drivers/pinctrl/sh-pfc/pinctrl.c
> @@ -26,6 +26,7 @@
> #include "../pinconf.h"
>
> struct sh_pfc_pin_config {
> + unsigned int mux_mark;
Due to padding, adding this field will increase memory consumption by
6 bytes per pin.
Probably sh_pfc_pin_group.{pins,mux} should be changed from unsigned int
to u16, but that's out of scope for this patch.
> bool mux_set;
> bool gpio_enabled;
> };
> @@ -353,6 +354,15 @@ static int sh_pfc_func_set_mux(struct pinctrl_dev *pctldev, unsigned selector,
> spin_lock_irqsave(&pfc->lock, flags);
>
> for (i = 0; i < grp->nr_pins; ++i) {
> + int idx = sh_pfc_get_pin_index(pfc, grp->pins[i]);
> + struct sh_pfc_pin_config *cfg = &pmx->configs[idx];
> +
> + /*
> + * This doesn't assume the order which gpios are enabled
> + * and then mux is set.
I'm sorry, I don't understand what you mean?
Can you please reword or elaborate?
> + */
> + WARN_ON(cfg->gpio_enabled);
Can this actually happen?
Should this cause a failure instead?
> +
> ret = sh_pfc_config_mux(pfc, grp->mux[i], PINMUX_TYPE_FUNCTION);
> if (ret < 0)
> goto done;
> @@ -364,6 +374,7 @@ static int sh_pfc_func_set_mux(struct pinctrl_dev *pctldev, unsigned selector,
> struct sh_pfc_pin_config *cfg = &pmx->configs[idx];
>
> cfg->mux_set = true;
> + cfg->mux_mark = grp->mux[i];
> }
>
> done:
> @@ -417,6 +428,9 @@ static void sh_pfc_gpio_disable_free(struct pinctrl_dev *pctldev,
>
> spin_lock_irqsave(&pfc->lock, flags);
> cfg->gpio_enabled = false;
> + /* If mux is already set, this configure it here */
configures
> + if (cfg->mux_set)
> + sh_pfc_config_mux(pfc, cfg->mux_mark, PINMUX_TYPE_FUNCTION);
Have you considered the case where more than one pin of a pinmux group
was used as a GPIO? In that case sh_pfc_gpio_disable_free() will be called
multiple times, possibly with the same mux_mark.
I don't think this will cause issues, though.
> spin_unlock_irqrestore(&pfc->lock, flags);
> }
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
