Re: [PATCH v2 2/2] Revert "usb: dwc3: Don't switch OTG -> peripheral if extcon is present"

[Andrey Smirnov <andrew.smirnov@gmail.com>]

On Tue, Sep 27, 2022 at 8:53 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> This reverts commit 0f01017191384e3962fa31520a9fd9846c3d352f.
>
> As pointed out by Ferry this breaks Dual Role support on
> Intel Merrifield platforms.
>
> Fixes: 0f0101719138 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present")
> Reported-by: Ferry Toth <fntoth@gmail.com>
> Cc: stable@vger.kernel.org
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Tested-by: Ferry Toth <fntoth@gmail.com> # for Merrifield

Sven can you check that this also fixes the regression of your fix?

> ---
>  drivers/usb/dwc3/core.c | 55 +----------------------------------------
>  drivers/usb/dwc3/drd.c  | 50 +++++++++++++++++++++++++++++++++++++
>  2 files changed, 51 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index c2b463469d51..219d797e2230 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -23,7 +23,6 @@
>  #include <linux/delay.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/of.h>
> -#include <linux/of_graph.h>
>  #include <linux/acpi.h>
>  #include <linux/pinctrl/consumer.h>
>  #include <linux/reset.h>
> @@ -86,7 +85,7 @@ static int dwc3_get_dr_mode(struct dwc3 *dwc)
>                  * mode. If the controller supports DRD but the dr_mode is not
>                  * specified or set to OTG, then set the mode to peripheral.
>                  */
> -               if (mode == USB_DR_MODE_OTG && !dwc->edev &&
> +               if (mode == USB_DR_MODE_OTG &&
>                     (!IS_ENABLED(CONFIG_USB_ROLE_SWITCH) ||
>                      !device_property_read_bool(dwc->dev, "usb-role-switch")) &&
>                     !DWC3_VER_IS_PRIOR(DWC3, 330A))
> @@ -1668,51 +1667,6 @@ static void dwc3_check_params(struct dwc3 *dwc)
>         }
>  }
>
> -static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
> -{
> -       struct device *dev = dwc->dev;
> -       struct device_node *np_phy;
> -       struct extcon_dev *edev = NULL;
> -       const char *name;
> -
> -       if (device_property_read_bool(dev, "extcon"))
> -               return extcon_get_edev_by_phandle(dev, 0);
> -
> -       /*
> -        * Device tree platforms should get extcon via phandle.
> -        * On ACPI platforms, we get the name from a device property.
> -        * This device property is for kernel internal use only and
> -        * is expected to be set by the glue code.
> -        */
> -       if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) {
> -               edev = extcon_get_extcon_dev(name);
> -               if (!edev)
> -                       return ERR_PTR(-EPROBE_DEFER);
> -
> -               return edev;
> -       }
> -
> -       /*
> -        * Try to get an extcon device from the USB PHY controller's "port"
> -        * node. Check if it has the "port" node first, to avoid printing the
> -        * error message from underlying code, as it's a valid case: extcon
> -        * device (and "port" node) may be missing in case of "usb-role-switch"
> -        * or OTG mode.
> -        */
> -       np_phy = of_parse_phandle(dev->of_node, "phys", 0);
> -       if (of_graph_is_present(np_phy)) {
> -               struct device_node *np_conn;
> -
> -               np_conn = of_graph_get_remote_node(np_phy, -1, -1);
> -               if (np_conn)
> -                       edev = extcon_find_edev_by_node(np_conn);
> -               of_node_put(np_conn);
> -       }
> -       of_node_put(np_phy);
> -
> -       return edev;
> -}
> -
>  static int dwc3_probe(struct platform_device *pdev)
>  {
>         struct device           *dev = &pdev->dev;
> @@ -1849,13 +1803,6 @@ static int dwc3_probe(struct platform_device *pdev)
>                 goto err2;
>         }
>
> -       dwc->edev = dwc3_get_extcon(dwc);
> -       if (IS_ERR(dwc->edev)) {
> -               ret = PTR_ERR(dwc->edev);
> -               dev_err_probe(dwc->dev, ret, "failed to get extcon\n");
> -               goto err3;
> -       }
> -
>         ret = dwc3_get_dr_mode(dwc);
>         if (ret)
>                 goto err3;
> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
> index 039bf241769a..8cad9e7d3368 100644
> --- a/drivers/usb/dwc3/drd.c
> +++ b/drivers/usb/dwc3/drd.c
> @@ -8,6 +8,7 @@
>   */
>
>  #include <linux/extcon.h>
> +#include <linux/of_graph.h>
>  #include <linux/of_platform.h>
>  #include <linux/platform_device.h>
>  #include <linux/property.h>
> @@ -438,6 +439,51 @@ static int dwc3_drd_notifier(struct notifier_block *nb,
>         return NOTIFY_DONE;
>  }
>
> +static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
> +{
> +       struct device *dev = dwc->dev;
> +       struct device_node *np_phy;
> +       struct extcon_dev *edev = NULL;
> +       const char *name;
> +
> +       if (device_property_read_bool(dev, "extcon"))
> +               return extcon_get_edev_by_phandle(dev, 0);
> +
> +       /*
> +        * Device tree platforms should get extcon via phandle.
> +        * On ACPI platforms, we get the name from a device property.
> +        * This device property is for kernel internal use only and
> +        * is expected to be set by the glue code.
> +        */
> +       if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) {
> +               edev = extcon_get_extcon_dev(name);
> +               if (!edev)
> +                       return ERR_PTR(-EPROBE_DEFER);
> +
> +               return edev;
> +       }
> +
> +       /*
> +        * Try to get an extcon device from the USB PHY controller's "port"
> +        * node. Check if it has the "port" node first, to avoid printing the
> +        * error message from underlying code, as it's a valid case: extcon
> +        * device (and "port" node) may be missing in case of "usb-role-switch"
> +        * or OTG mode.
> +        */
> +       np_phy = of_parse_phandle(dev->of_node, "phys", 0);
> +       if (of_graph_is_present(np_phy)) {
> +               struct device_node *np_conn;
> +
> +               np_conn = of_graph_get_remote_node(np_phy, -1, -1);
> +               if (np_conn)
> +                       edev = extcon_find_edev_by_node(np_conn);
> +               of_node_put(np_conn);
> +       }
> +       of_node_put(np_phy);
> +
> +       return edev;
> +}
> +
>  #if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
>  #define ROLE_SWITCH 1
>  static int dwc3_usb_role_switch_set(struct usb_role_switch *sw,
> @@ -542,6 +588,10 @@ int dwc3_drd_init(struct dwc3 *dwc)
>             device_property_read_bool(dwc->dev, "usb-role-switch"))
>                 return dwc3_setup_role_switch(dwc);
>
> +       dwc->edev = dwc3_get_extcon(dwc);
> +       if (IS_ERR(dwc->edev))
> +               return PTR_ERR(dwc->edev);
> +
>         if (dwc->edev) {
>                 dwc->edev_nb.notifier_call = dwc3_drd_notifier;
>                 ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
> --
> 2.35.1
>