Re: [PATCH v4 5/9] can: m_can: Support pinctrl wakeup state

[Vincent MAILHOL <mailhol.vincent@wanadoo.fr>]

Hi Markus,

This is a nice improvement from the v3.

On Wed. 16 Oct. 2024 at 04:19, Markus Schneider-Pargmann
<msp@baylibre.com> wrote:
> am62 requires a wakeup flag being set in pinctrl when mcan pins acts as
> a wakeup source. Add support to select the wakeup state if WOL is
> enabled.
>
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> ---
>  drivers/net/can/m_can/m_can.c | 68 +++++++++++++++++++++++++++++++++++++++++++
>  drivers/net/can/m_can/m_can.h |  4 +++
>  2 files changed, 72 insertions(+)
>
> diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
> index 5a4e0ad07e9ecc82de5f1f606707f3380d3679fc..c539375005f71c88fd1f7d1a885ce890ce0e9327 100644
> --- a/drivers/net/can/m_can/m_can.c
> +++ b/drivers/net/can/m_can/m_can.c
> @@ -2196,6 +2196,7 @@ static void m_can_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
>  static int m_can_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
>  {
>         struct m_can_classdev *cdev = netdev_priv(dev);
> +       struct pinctrl_state *new_pinctrl_state = NULL;
>         bool wol_enable = !!(wol->wolopts & WAKE_PHY);
>         int ret;
>
> @@ -2212,7 +2213,28 @@ static int m_can_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
>                 return ret;
>         }
>
> +       if (wol_enable)
> +               new_pinctrl_state = cdev->pinctrl_state_wakeup;
> +       else
> +               new_pinctrl_state = cdev->pinctrl_state_default;
> +
> +       if (IS_ERR_OR_NULL(new_pinctrl_state))
> +               return 0;
> +
> +       ret = pinctrl_select_state(cdev->pinctrl, new_pinctrl_state);
> +       if (ret) {
> +               netdev_err(cdev->net, "Failed to select pinctrl state %pE\n",
> +                          ERR_PTR(ret));
> +               goto err_wakeup_enable;
> +       }
> +
>         return 0;
> +
> +err_wakeup_enable:
> +       /* Revert wakeup enable */
> +       device_set_wakeup_enable(cdev->dev, !wol_enable);
> +
> +       return ret;
>  }
>
>  static const struct ethtool_ops m_can_ethtool_ops_coalescing = {
> @@ -2340,6 +2362,44 @@ int m_can_class_get_clocks(struct m_can_classdev *cdev)
>  }
>  EXPORT_SYMBOL_GPL(m_can_class_get_clocks);
>
> +static int m_can_class_setup_optional_pinctrl(struct m_can_classdev *class_dev)
> +{
> +       struct device *dev = class_dev->dev;
> +       int ret;
> +
> +       class_dev->pinctrl = devm_pinctrl_get(dev);
> +       if (IS_ERR(class_dev->pinctrl)) {
> +               ret = PTR_ERR(class_dev->pinctrl);
> +               class_dev->pinctrl = NULL;
> +
> +               if (ret == -ENODEV)
> +                       return 0;
> +
> +               return dev_err_probe(dev, ret, "Failed to get pinctrl\n");
> +       }
> +
> +       class_dev->pinctrl_state_wakeup =
> +               pinctrl_lookup_state(class_dev->pinctrl, "wakeup");
> +       if (IS_ERR(class_dev->pinctrl_state_wakeup)) {
> +               ret = PTR_ERR(class_dev->pinctrl_state_wakeup);
> +               class_dev->pinctrl_state_wakeup = NULL;
> +
> +               if (ret == -ENODEV)
> +                       return 0;
> +
> +               return dev_err_probe(dev, ret, "Failed to lookup pinctrl wakeup state\n");
> +       }
> +
> +       class_dev->pinctrl_state_default =
> +               pinctrl_lookup_state(class_dev->pinctrl, "default");
> +       if (IS_ERR(class_dev->pinctrl_state_default)) {
> +               ret = PTR_ERR(class_dev->pinctrl_state_default);

Sorry if this is a silly question, but why aren't you doing the:

                  class_dev->pinctrl_state_default = NULL;

                  if (ret == -ENODEV)
                          return 0;

thing the same way you are doing it for the pinctrl and the
pinctrl_state_wakeup?

> +               return dev_err_probe(dev, ret, "Failed to lookup pinctrl default state\n");
> +       }
> +
> +       return 0;
> +}
> +
>  struct m_can_classdev *m_can_class_allocate_dev(struct device *dev,
>                                                 int sizeof_priv)
>  {
> @@ -2380,7 +2440,15 @@ struct m_can_classdev *m_can_class_allocate_dev(struct device *dev,
>
>         m_can_of_parse_mram(class_dev, mram_config_vals);
>
> +       ret = m_can_class_setup_optional_pinctrl(class_dev);
> +       if (ret)
> +               goto err_free_candev;
> +
>         return class_dev;
> +
> +err_free_candev:
> +       free_candev(net_dev);
> +       return ERR_PTR(ret);
>  }
>  EXPORT_SYMBOL_GPL(m_can_class_allocate_dev);
>
> diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
> index 92b2bd8628e6b31370f4accbc2e28f3b2257a71d..b75b0dd6ccc93973d0891daac07c92b61f81dc2a 100644
> --- a/drivers/net/can/m_can/m_can.h
> +++ b/drivers/net/can/m_can/m_can.h
> @@ -126,6 +126,10 @@ struct m_can_classdev {
>         struct mram_cfg mcfg[MRAM_CFG_NUM];
>
>         struct hrtimer hrtimer;
> +
> +       struct pinctrl *pinctrl;
> +       struct pinctrl_state *pinctrl_state_default;
> +       struct pinctrl_state *pinctrl_state_wakeup;
>  };
>
>  struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv);