FM / usb

/usr/include/linux/usb

Name	Size	Mode	Actions
audio.h	19490	0644	edit dl rm
cdc-wdm.h	739	0644	edit dl rm
cdc.h	12962	0644	edit dl rm
ch9.h	38947	0644	edit dl rm
ch11.h	9149	0644	edit dl rm
charger.h	598	0644	edit dl rm
functionfs.h	10370	0644	edit dl rm
gadgetfs.h	2818	0644	edit dl rm
g_printer.h	1385	0644	edit dl rm
g_uvc.h	1097	0644	edit dl rm
midi.h	3434	0644	edit dl rm
tmc.h	4713	0644	edit dl rm
video.h	17295	0644	edit dl rm

Edit: /usr/include/linux/usb/gadgetfs.h (2818B)

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
 * 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 */

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