diff options
Diffstat (limited to 'include/uapi/linux/usb/gadgetfs.h')
-rw-r--r-- | include/uapi/linux/usb/gadgetfs.h | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/include/uapi/linux/usb/gadgetfs.h b/include/uapi/linux/usb/gadgetfs.h new file mode 100644 index 00000000000..0bb12e0d4f8 --- /dev/null +++ b/include/uapi/linux/usb/gadgetfs.h @@ -0,0 +1,88 @@ +/* + * Filesystem based user-mode API to USB Gadget controller hardware + * + * Other than ep0 operations, most things are done by read() and write() + * 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. Operations on + * ep0 require ioctl() operations. + * + * 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. + */ + +#ifndef __LINUX_USB_GADGETFS_H +#define __LINUX_USB_GADGETFS_H + +#include <linux/types.h> +#include <linux/ioctl.h> + +#include <linux/usb/ch9.h> + +/* + * Events are delivered on the ep0 file descriptor, when the user mode driver + * reads from this file descriptor after writing the descriptors. Don't + * stop polling this descriptor. + */ + +enum usb_gadgetfs_event_type { + GADGETFS_NOP = 0, + + GADGETFS_CONNECT, + GADGETFS_DISCONNECT, + GADGETFS_SETUP, + GADGETFS_SUSPEND, + /* and likely more ! */ +}; + +/* NOTE: this structure must stay the same size and layout on + * both 32-bit and 64-bit kernels. + */ +struct usb_gadgetfs_event { + 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; + enum usb_gadgetfs_event_type type; +}; + + +/* The 'g' code is also used by printer gadget ioctl requests. + * Don't add any colliding codes to either driver, and keep + * them in unique ranges (size 0x20 for now). + */ + +/* 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) + +#endif /* __LINUX_USB_GADGETFS_H */ |