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 usb_role_switch *sw, 17 enum usb_role role); 18 typedef enum usb_role (*usb_role_switch_get_t)(struct usb_role_switch *sw); 19 20 /** 21 * struct usb_role_switch_desc - USB Role Switch Descriptor 22 * @fwnode: The device node to be associated with the role switch 23 * @usb2_port: Optional reference to the host controller port device (USB2) 24 * @usb3_port: Optional reference to the host controller port device (USB3) 25 * @udc: Optional reference to the peripheral controller device 26 * @set: Callback for setting the role 27 * @get: Callback for getting the role (optional) 28 * @allow_userspace_control: If true userspace may change the role through sysfs 29 * @driver_data: Private data pointer 30 * @name: Name for the switch (optional) 31 * 32 * @usb2_port and @usb3_port will point to the USB host port and @udc to the USB 33 * device controller behind the USB connector with the role switch. If 34 * @usb2_port, @usb3_port and @udc are included in the description, the 35 * reference count for them should be incremented by the caller of 36 * usb_role_switch_register() before registering the switch. 37 */ 38 struct usb_role_switch_desc { 39 struct fwnode_handle *fwnode; 40 struct device *usb2_port; 41 struct device *usb3_port; 42 struct device *udc; 43 usb_role_switch_set_t set; 44 usb_role_switch_get_t get; 45 bool allow_userspace_control; 46 void *driver_data; 47 const char *name; 48 }; 49 50 51 #if IS_ENABLED(CONFIG_USB_ROLE_SWITCH) 52 int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role); 53 enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw); 54 struct usb_role_switch *usb_role_switch_get(struct device *dev); 55 struct usb_role_switch *fwnode_usb_role_switch_get(struct fwnode_handle *node); 56 void usb_role_switch_put(struct usb_role_switch *sw); 57 58 struct usb_role_switch * 59 usb_role_switch_find_by_fwnode(const struct fwnode_handle *fwnode); 60 61 struct usb_role_switch * 62 usb_role_switch_register(struct device *parent, 63 const struct usb_role_switch_desc *desc); 64 void usb_role_switch_unregister(struct usb_role_switch *sw); 65 66 void usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data); 67 void *usb_role_switch_get_drvdata(struct usb_role_switch *sw); 68 const char *usb_role_string(enum usb_role role); 69 #else 70 static inline int usb_role_switch_set_role(struct usb_role_switch *sw, 71 enum usb_role role) 72 { 73 return 0; 74 } 75 76 static inline enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw) 77 { 78 return USB_ROLE_NONE; 79 } 80 81 static inline struct usb_role_switch *usb_role_switch_get(struct device *dev) 82 { 83 return ERR_PTR(-ENODEV); 84 } 85 86 static inline struct usb_role_switch * 87 fwnode_usb_role_switch_get(struct fwnode_handle *node) 88 { 89 return ERR_PTR(-ENODEV); 90 } 91 92 static inline void usb_role_switch_put(struct usb_role_switch *sw) { } 93 94 static inline struct usb_role_switch * 95 usb_role_switch_find_by_fwnode(const struct fwnode_handle *fwnode) 96 { 97 return NULL; 98 } 99 100 static inline struct usb_role_switch * 101 usb_role_switch_register(struct device *parent, 102 const struct usb_role_switch_desc *desc) 103 { 104 return ERR_PTR(-ENODEV); 105 } 106 107 static inline void usb_role_switch_unregister(struct usb_role_switch *sw) { } 108 109 static inline void 110 usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data) 111 { 112 } 113 114 static inline void *usb_role_switch_get_drvdata(struct usb_role_switch *sw) 115 { 116 return NULL; 117 } 118 119 static inline const char *usb_role_string(enum usb_role role) 120 { 121 return "unknown"; 122 } 123 124 #endif 125 126 #endif /* __LINUX_USB_ROLE_H */ 127