1 #ifndef __LINUX_USB_GADGETFS_H 2 #define __LINUX_USB_GADGETFS_H 3 4 #include <asm/types.h> 5 #include <asm/ioctl.h> 6 7 #include <linux/usb/ch9.h> 8 9 /* 10 * Filesystem based user-mode API to USB Gadget controller hardware 11 * 12 * Other than ep0 operations, most things are done by read() and write() 13 * on endpoint files found in one directory. They are configured by 14 * writing descriptors, and then may be used for normal stream style 15 * i/o requests. When ep0 is configured, the device can enumerate; 16 * when it's closed, the device disconnects from usb. Operations on 17 * ep0 require ioctl() operations. 18 * 19 * Configuration and device descriptors get written to /dev/gadget/$CHIP, 20 * which may then be used to read usb_gadgetfs_event structs. The driver 21 * may activate endpoints as it handles SET_CONFIGURATION setup events, 22 * or earlier; writing endpoint descriptors to /dev/gadget/$ENDPOINT 23 * then performing data transfers by reading or writing. 24 */ 25 26 /* 27 * Events are delivered on the ep0 file descriptor, when the user mode driver 28 * reads from this file descriptor after writing the descriptors. Don't 29 * stop polling this descriptor. 30 */ 31 32 enum usb_gadgetfs_event_type { 33 GADGETFS_NOP = 0, 34 35 GADGETFS_CONNECT, 36 GADGETFS_DISCONNECT, 37 GADGETFS_SETUP, 38 GADGETFS_SUSPEND, 39 // and likely more ! 40 }; 41 42 /* NOTE: this structure must stay the same size and layout on 43 * both 32-bit and 64-bit kernels. 44 */ 45 struct usb_gadgetfs_event { 46 union { 47 // NOP, DISCONNECT, SUSPEND: nothing 48 // ... some hardware can't report disconnection 49 50 // CONNECT: just the speed 51 enum usb_device_speed speed; 52 53 // SETUP: packet; DATA phase i/o precedes next event 54 // (setup.bmRequestType & USB_DIR_IN) flags direction 55 // ... includes SET_CONFIGURATION, SET_INTERFACE 56 struct usb_ctrlrequest setup; 57 } u; 58 enum usb_gadgetfs_event_type type; 59 }; 60 61 62 /* endpoint ioctls */ 63 64 /* IN transfers may be reported to the gadget driver as complete 65 * when the fifo is loaded, before the host reads the data; 66 * OUT transfers may be reported to the host's "client" driver as 67 * complete when they're sitting in the FIFO unread. 68 * THIS returns how many bytes are "unclaimed" in the endpoint fifo 69 * (needed for precise fault handling, when the hardware allows it) 70 */ 71 #define GADGETFS_FIFO_STATUS _IO('g',1) 72 73 /* discards any unclaimed data in the fifo. */ 74 #define GADGETFS_FIFO_FLUSH _IO('g',2) 75 76 /* resets endpoint halt+toggle; used to implement set_interface. 77 * some hardware (like pxa2xx) can't support this. 78 */ 79 #define GADGETFS_CLEAR_HALT _IO('g',3) 80 81 #endif /* __LINUX_USB_GADGETFS_H */ 82
