root/include/linux/usb/role.h

INCLUDED FROM

   1 // SPDX-License-Identifier: GPL-2.0
   2 
   3 #ifndef __LINUX_USB_ROLE_H
   4 #define __LINUX_USB_ROLE_H
   5 
   6 #include <linux/device.h>
   7 
   8 struct usb_role_switch;
   9 
  10 enum usb_role {
  11         USB_ROLE_NONE,
  12         USB_ROLE_HOST,
  13         USB_ROLE_DEVICE,
  14 };
  15 
  16 typedef int (*usb_role_switch_set_t)(struct device *dev, enum usb_role role);
  17 typedef enum usb_role (*usb_role_switch_get_t)(struct device *dev);
  18 
  19 /**
  20  * struct usb_role_switch_desc - USB Role Switch Descriptor
  21  * @fwnode: The device node to be associated with the role switch
  22  * @usb2_port: Optional reference to the host controller port device (USB2)
  23  * @usb3_port: Optional reference to the host controller port device (USB3)
  24  * @udc: Optional reference to the peripheral controller device
  25  * @set: Callback for setting the role
  26  * @get: Callback for getting the role (optional)
  27  * @allow_userspace_control: If true userspace may change the role through sysfs
  28  *
  29  * @usb2_port and @usb3_port will point to the USB host port and @udc to the USB
  30  * device controller behind the USB connector with the role switch. If
  31  * @usb2_port, @usb3_port and @udc are included in the description, the
  32  * reference count for them should be incremented by the caller of
  33  * usb_role_switch_register() before registering the switch.
  34  */
  35 struct usb_role_switch_desc {
  36         struct fwnode_handle *fwnode;
  37         struct device *usb2_port;
  38         struct device *usb3_port;
  39         struct device *udc;
  40         usb_role_switch_set_t set;
  41         usb_role_switch_get_t get;
  42         bool allow_userspace_control;
  43 };
  44 
  45 
  46 #if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
  47 int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role);
  48 enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw);
  49 struct usb_role_switch *usb_role_switch_get(struct device *dev);
  50 struct usb_role_switch *fwnode_usb_role_switch_get(struct fwnode_handle *node);
  51 void usb_role_switch_put(struct usb_role_switch *sw);
  52 
  53 struct usb_role_switch *
  54 usb_role_switch_register(struct device *parent,
  55                          const struct usb_role_switch_desc *desc);
  56 void usb_role_switch_unregister(struct usb_role_switch *sw);
  57 #else
  58 static inline int usb_role_switch_set_role(struct usb_role_switch *sw,
  59                 enum usb_role role)
  60 {
  61         return 0;
  62 }
  63 
  64 static inline enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
  65 {
  66         return USB_ROLE_NONE;
  67 }
  68 
  69 static inline struct usb_role_switch *usb_role_switch_get(struct device *dev)
  70 {
  71         return ERR_PTR(-ENODEV);
  72 }
  73 
  74 static inline struct usb_role_switch *
  75 fwnode_usb_role_switch_get(struct fwnode_handle *node)
  76 {
  77         return ERR_PTR(-ENODEV);
  78 }
  79 
  80 static inline void usb_role_switch_put(struct usb_role_switch *sw) { }
  81 
  82 static inline struct usb_role_switch *
  83 usb_role_switch_register(struct device *parent,
  84                          const struct usb_role_switch_desc *desc)
  85 {
  86         return ERR_PTR(-ENODEV);
  87 }
  88 
  89 static inline void usb_role_switch_unregister(struct usb_role_switch *sw) { }
  90 #endif
  91 
  92 #endif /* __LINUX_USB_ROLE_H */