cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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gadgetfs.h (2818B)

      1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
      2/*
      3 * Filesystem based user-mode API to USB Gadget controller hardware
      4 *
      5 * Other than ep0 operations, most things are done by read() and write()
      6 * on endpoint files found in one directory.  They are configured by
      7 * writing descriptors, and then may be used for normal stream style
      8 * i/o requests.  When ep0 is configured, the device can enumerate;
      9 * when it's closed, the device disconnects from usb.  Operations on
     10 * ep0 require ioctl() operations.
     11 *
     12 * Configuration and device descriptors get written to /dev/gadget/$CHIP,
     13 * which may then be used to read usb_gadgetfs_event structs.  The driver
     14 * may activate endpoints as it handles SET_CONFIGURATION setup events,
     15 * or earlier; writing endpoint descriptors to /dev/gadget/$ENDPOINT
     16 * then performing data transfers by reading or writing.
     17 */
     18
     19#ifndef __LINUX_USB_GADGETFS_H
     20#define __LINUX_USB_GADGETFS_H
     21
     22#include <linux/types.h>
     23#include <linux/ioctl.h>
     24
     25#include <linux/usb/ch9.h>
     26
     27/*
     28 * Events are delivered on the ep0 file descriptor, when the user mode driver
     29 * reads from this file descriptor after writing the descriptors.  Don't
     30 * stop polling this descriptor.
     31 */
     32
     33enum usb_gadgetfs_event_type {
     34	GADGETFS_NOP = 0,
     35
     36	GADGETFS_CONNECT,
     37	GADGETFS_DISCONNECT,
     38	GADGETFS_SETUP,
     39	GADGETFS_SUSPEND,
     40	/* and likely more ! */
     41};
     42
     43/* NOTE:  this structure must stay the same size and layout on
     44 * both 32-bit and 64-bit kernels.
     45 */
     46struct usb_gadgetfs_event {
     47	union {
     48		/* NOP, DISCONNECT, SUSPEND: nothing
     49		 * ... some hardware can't report disconnection
     50		 */
     51
     52		/* CONNECT: just the speed */
     53		enum usb_device_speed	speed;
     54
     55		/* SETUP: packet; DATA phase i/o precedes next event
     56		 *(setup.bmRequestType & USB_DIR_IN) flags direction
     57		 * ... includes SET_CONFIGURATION, SET_INTERFACE
     58		 */
     59		struct usb_ctrlrequest	setup;
     60	} u;
     61	enum usb_gadgetfs_event_type	type;
     62};
     63
     64
     65/* The 'g' code is also used by printer gadget ioctl requests.
     66 * Don't add any colliding codes to either driver, and keep
     67 * them in unique ranges (size 0x20 for now).
     68 */
     69
     70/* endpoint ioctls */
     71
     72/* IN transfers may be reported to the gadget driver as complete
     73 *	when the fifo is loaded, before the host reads the data;
     74 * OUT transfers may be reported to the host's "client" driver as
     75 *	complete when they're sitting in the FIFO unread.
     76 * THIS returns how many bytes are "unclaimed" in the endpoint fifo
     77 * (needed for precise fault handling, when the hardware allows it)
     78 */
     79#define	GADGETFS_FIFO_STATUS	_IO('g', 1)
     80
     81/* discards any unclaimed data in the fifo. */
     82#define	GADGETFS_FIFO_FLUSH	_IO('g', 2)
     83
     84/* resets endpoint halt+toggle; used to implement set_interface.
     85 * some hardware (like pxa2xx) can't support this.
     86 */
     87#define	GADGETFS_CLEAR_HALT	_IO('g', 3)
     88
     89#endif /* __LINUX_USB_GADGETFS_H */