#include <asm/types.h> #include <asm/ioctl.h> #include <linux/usb_ch9.h> /* * Filesystem based user-mode API to USB Gadget controller hardware * * Almost everything can be done with only read and write operations, * on endpoint files found in one directory. They are configured by * writing descriptors, and then may be used for normal stream style * i/o requests. When ep0 is configured, the device can enumerate; * when it's closed, the device disconnects from usb. * * Configuration and device descriptors get written to /dev/gadget/$CHIP, * which may then be used to read usb_gadgetfs_event structs. The driver * may activate endpoints as it handles SET_CONFIGURATION setup events, * or earlier; writing endpoint descriptors to /dev/gadget/$ENDPOINT * then performing data transfers by reading or writing. */ /* * Events are delivered on the ep0 file descriptor, if the user mode driver * reads from this file descriptor after writing the descriptors. Don't * stop polling this descriptor, if you write that kind of driver. */ enum usb_gadgetfs_event_type { GADGETFS_NOP = 0, GADGETFS_CONNECT, GADGETFS_DISCONNECT, GADGETFS_SETUP, GADGETFS_SUSPEND, // and likely more ! }; struct usb_gadgetfs_event { enum usb_gadgetfs_event_type type; union { // NOP, DISCONNECT, SUSPEND: nothing // ... some hardware can't report disconnection // CONNECT: just the speed enum usb_device_speed speed; // SETUP: packet; DATA phase i/o precedes next event // (setup.bmRequestType & USB_DIR_IN) flags direction // ... includes SET_CONFIGURATION, SET_INTERFACE struct usb_ctrlrequest setup; } u; }; /* endpoint ioctls */ /* IN transfers may be reported to the gadget driver as complete * when the fifo is loaded, before the host reads the data; * OUT transfers may be reported to the host's "client" driver as * complete when they're sitting in the FIFO unread. * THIS returns how many bytes are "unclaimed" in the endpoint fifo * (needed for precise fault handling, when the hardware allows it) */ #define GADGETFS_FIFO_STATUS _IO('g',1) /* discards any unclaimed data in the fifo. */ #define GADGETFS_FIFO_FLUSH _IO('g',2) /* resets endpoint halt+toggle; used to implement set_interface. * some hardware (like pxa2xx) can't support this. */ #define GADGETFS_CLEAR_HALT _IO('g',3)