| Message ID | 1678393499-7366-1-git-send-email-quic_eserrao@quicinc.com |
|---|---|
| Headers | show |
| Series | Add function suspend/resume and remote wakeup support | expand |
On Thu, Mar 09, 2023, Elson Roy Serrao wrote: > USB3.2 spec section 9.2.5.4 quotes that a function may signal that > it wants to exit from Function Suspend by sending a Function > Wake Notification to the host if it is enabled for function > remote wakeup. Add an api in composite layer that can be used > by the function drivers to support this feature. Also expose > a gadget op so that composite layer can trigger a wakeup request > to the UDC driver. > > Signed-off-by: Elson Roy Serrao <quic_eserrao@quicinc.com> > --- > drivers/usb/gadget/composite.c | 40 ++++++++++++++++++++++++++++++++++++++++ > include/linux/usb/composite.h | 6 ++++++ > include/linux/usb/gadget.h | 1 + > 3 files changed, 47 insertions(+) > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c > index c9c983e..2111732 100644 > --- a/drivers/usb/gadget/composite.c > +++ b/drivers/usb/gadget/composite.c > @@ -492,6 +492,46 @@ int usb_interface_id(struct usb_configuration *config, > } > EXPORT_SYMBOL_GPL(usb_interface_id); > > +/** > + * usb_func_wakeup - sends function wake notification to the host. > + * @func: function that sends the remote wakeup notification. > + * > + * Applicable to devices operating at enhanced superspeed when usb > + * functions are put in function suspend state and armed for function > + * remote wakeup. On completion, function wake notification is sent. If > + * the device is in low power state it tries to bring the device to active > + * state before sending the wake notification. Since it is a synchronous > + * call, caller must take care of not calling it in interrupt context. > + * For devices operating at lower speeds returns negative errno. > + * > + * Returns zero on success, else negative errno. > + */ > +int usb_func_wakeup(struct usb_function *func) > +{ > + struct usb_gadget *gadget = func->config->cdev->gadget; > + int id; > + > + if (!gadget->ops->func_wakeup) > + return -EOPNOTSUPP; > + > + if (!func->func_wakeup_armed) { > + ERROR(func->config->cdev, "not armed for func remote wakeup\n"); > + return -EINVAL; > + } > + > + for (id = 0; id < MAX_CONFIG_INTERFACES; id++) > + if (func->config->interface[id] == func) > + break; > + > + if (id == MAX_CONFIG_INTERFACES) { > + ERROR(func->config->cdev, "Invalid function\n"); > + return -EINVAL; > + } > + > + return gadget->ops->func_wakeup(gadget, id); > +} > +EXPORT_SYMBOL_GPL(usb_func_wakeup); > + > static u8 encode_bMaxPower(enum usb_device_speed speed, > struct usb_configuration *c) > { > diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h > index d949e91..a2448e9 100644 > --- a/include/linux/usb/composite.h > +++ b/include/linux/usb/composite.h > @@ -150,6 +150,9 @@ struct usb_os_desc_table { > * GetStatus() request when the recipient is Interface. > * @func_suspend: callback to be called when > * SetFeature(FUNCTION_SUSPEND) is reseived > + * @func_suspended: Indicates whether the function is in function suspend state. > + * @func_wakeup_armed: Indicates whether the function is armed by the host for > + * wakeup signaling. > * > * A single USB function uses one or more interfaces, and should in most > * cases support operation at both full and high speeds. Each function is > @@ -220,6 +223,8 @@ struct usb_function { > int (*get_status)(struct usb_function *); > int (*func_suspend)(struct usb_function *, > u8 suspend_opt); > + bool func_suspended; > + bool func_wakeup_armed; > /* private: */ > /* internals */ > struct list_head list; > @@ -241,6 +246,7 @@ int config_ep_by_speed_and_alt(struct usb_gadget *g, struct usb_function *f, > > int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f, > struct usb_ep *_ep); > +int usb_func_wakeup(struct usb_function *func); > > #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */ > > diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h > index 1d79612..75bda078 100644 > --- a/include/linux/usb/gadget.h > +++ b/include/linux/usb/gadget.h > @@ -310,6 +310,7 @@ struct usb_udc; > struct usb_gadget_ops { > int (*get_frame)(struct usb_gadget *); > int (*wakeup)(struct usb_gadget *); > + int (*func_wakeup)(struct usb_gadget *gadget, int intf_id); > int (*set_remote_wakeup)(struct usb_gadget *, int set); > int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered); > int (*vbus_session) (struct usb_gadget *, int is_active); > -- > 2.7.4 > Reviewed-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> Thanks, Thinh