Hi
Yu Chen <chenyu56@xxxxxxxxxx> 于2019年2月18日周一 下午7:34写道：
>
> The Type-C drivers use USB role switch API to inform the
> system about the negotiated data role, so registering a role
> switch in the DRD code in order to support platforms with
> USB Type-C connectors.
>
> Cc: John Stultz <john.stultz@xxxxxxxxxx>
> Cc: Felipe Balbi <balbi@xxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Suggested-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Signed-off-by: Yu Chen <chenyu56@xxxxxxxxxx>
> ---
> v2:
> * Assign fwnode in dwc3_role_switch.
> ---
> ---
> drivers/usb/dwc3/core.h | 2 ++
> drivers/usb/dwc3/drd.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 47 insertions(+)
>
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 402b3c29eb26..7385544b9936 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -25,6 +25,7 @@
> #include <linux/usb/ch9.h>
> #include <linux/usb/gadget.h>
> #include <linux/usb/otg.h>
> +#include <linux/usb/role.h>
> #include <linux/ulpi/interface.h>
>
> #include <linux/phy/phy.h>
> @@ -1083,6 +1084,7 @@ struct dwc3 {
> struct extcon_dev *edev;
> struct notifier_block edev_nb;
> enum usb_phy_interface hsphy_mode;
> + struct usb_role_switch *role_sw;
>
> u32 fladj;
> u32 irq_gadget;
> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
> index 869725d15c74..cf977bb0d62e 100644
> --- a/drivers/usb/dwc3/drd.c
> +++ b/drivers/usb/dwc3/drd.c
> @@ -474,8 +474,42 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
> return edev;
> }
>
> +static int dwc3_usb_role_switch_set(struct device *dev, enum usb_role role)
> +{
> + u32 mode;
> +
> + switch (role) {
> + case USB_ROLE_HOST:
> + mode = DWC3_GCTL_PRTCAP_HOST;
> + break;
> + case USB_ROLE_DEVICE:
> + mode = DWC3_GCTL_PRTCAP_DEVICE;
> + break;
> + default:
> + mode = DWC3_GCTL_PRTCAP_HOST;
I'd propose let dwc3 stay at device mode at default case.
> + break;
> + };
> +
> + dwc3_set_mode(dev_get_drvdata(dev), mode);
> + return 0;
> +}
> +
> +static enum usb_role dwc3_usb_role_switch_get(struct device *dev)
> +{
> + struct dwc3 *dwc = dev_get_drvdata(dev);
> + unsigned long flags;
> + enum usb_role role;
> +
> + spin_lock_irqsave(&dwc->lock, flags);
> + role = dwc->current_otg_role;
> + spin_unlock_irqrestore(&dwc->lock, flags);
> +
> + return role;
> +}
> +
> int dwc3_drd_init(struct dwc3 *dwc)
> {
> + struct usb_role_switch_desc dwc3_role_switch = {0};
> int ret, irq;
>
> dwc->edev = dwc3_get_extcon(dwc);
> @@ -522,6 +556,15 @@ int dwc3_drd_init(struct dwc3 *dwc)
> dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
> }
>
> + dwc3_role_switch.fwnode = dev_fwnode(dwc->dev);
> + dwc3_role_switch.set = dwc3_usb_role_switch_set;
> + dwc3_role_switch.get = dwc3_usb_role_switch_get;
> + dwc->role_sw = usb_role_switch_register(dwc->dev, &dwc3_role_switch);
> + if (ret) {
> + dwc3_drd_exit(dwc);
> + return PTR_ERR(dwc->role_sw);
> + }
> +
My understanding is, if you use usb role switch, you don't need either edev or
OTG block event, so this should be like:
if (device_property_read_bool(dwc->dev, "usb-role-switch")) {
usb role switch register;
} else if (edev) {
...
} else {
...
}
Jun
> return 0;
> }
>
> @@ -557,4 +600,6 @@ void dwc3_drd_exit(struct dwc3 *dwc)
>
> if (!dwc->edev)
> free_irq(dwc->otg_irq, dwc);
> +
> + usb_role_switch_unregister(dwc->role_sw);
> }
> --
> 2.15.0-rc2
>
