Re: [PATCH v3 14/15] pinctrl: renesas: pinctrl-rzg2l: Acquire lock in rzg2l_pinctrl_pm_setup_pfc()

[Geert Uytterhoeven]

On Thu, May 30, 2024 at 7:42 PM Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
>
> To keep consistency with rzg2l_pinctrl_set_pfc_mode(), acquire the lock
> in rzg2l_pinctrl_pm_setup_pfc() during PFC setup.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> v2->v3
> - New patch

Thanks for your patch!

> --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> @@ -2541,7 +2541,9 @@ static void rzg2l_pinctrl_pm_setup_dedicated_regs(struct rzg2l_pinctrl *pctrl, b
>  static void rzg2l_pinctrl_pm_setup_pfc(struct rzg2l_pinctrl *pctrl)
>  {
>         u32 nports = pctrl->data->n_port_pins / RZG2L_PINS_PER_PORT;
> +       unsigned long flags;
>
> +       spin_lock_irqsave(&pctrl->lock, flags);
>         pctrl->data->pwpr_pfc_lock_unlock(pctrl, false);
>
>         /* Restore port registers. */
> @@ -2586,6 +2588,7 @@ static void rzg2l_pinctrl_pm_setup_pfc(struct rzg2l_pinctrl *pctrl)
>         }
>
>         pctrl->data->pwpr_pfc_lock_unlock(pctrl, true);
> +       spin_unlock_irqrestore(&pctrl->lock, flags);
>  }
>
>  static int rzg2l_pinctrl_suspend_noirq(struct device *dev)

It's definitely safer to unlock only while holding the lock.

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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