xhci-sideband.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * xHCI host controller sideband support
  4 *
  5 * Copyright (c) 2023-2025, Intel Corporation.
  6 *
  7 * Author: Mathias Nyman <mathias.nyman@linux.intel.com>
  8 */
  9#ifndef __LINUX_XHCI_SIDEBAND_H
 10#define __LINUX_XHCI_SIDEBAND_H
 11
 12#include <linux/scatterlist.h>
 13#include <linux/usb.h>
 14#include <linux/usb/hcd.h>
 15
 16#define	EP_CTX_PER_DEV		31	/* FIXME defined twice, from xhci.h */
 17
 18struct xhci_sideband;
 19
 20enum xhci_sideband_type {
 21	XHCI_SIDEBAND_AUDIO,
 22	XHCI_SIDEBAND_VENDOR,
 23};
 24
 25enum xhci_sideband_notify_type {
 26	XHCI_SIDEBAND_XFER_RING_FREE,
 27};
 28
 29/**
 30 * struct xhci_sideband_event - sideband event
 31 * @type: notifier type
 32 * @evt_data: event data
 33 */
 34struct xhci_sideband_event {
 35	enum xhci_sideband_notify_type type;
 36	void *evt_data;
 37};
 38
 39/**
 40 * struct xhci_sideband - representation of a sideband accessed usb device.
 41 * @xhci: The xhci host controller the usb device is connected to
 42 * @vdev: the usb device accessed via sideband
 43 * @eps: array of endpoints controlled via sideband
 44 * @ir: event handling and buffer for sideband accessed device
 45 * @type: xHCI sideband type
 46 * @mutex: mutex for sideband operations
 47 * @intf: USB sideband client interface
 48 * @notify_client: callback for xHCI sideband sequences
 49 *
 50 * FIXME usb device accessed via sideband Keeping track of sideband accessed usb devices.
 51 */
 52struct xhci_sideband {
 53	struct xhci_hcd                 *xhci;
 54	struct xhci_virt_device         *vdev;
 55	struct xhci_virt_ep             *eps[EP_CTX_PER_DEV];
 56	struct xhci_interrupter         *ir;
 57	enum xhci_sideband_type		type;
 58
 59	/* Synchronizing xHCI sideband operations with client drivers operations */
 60	struct mutex			mutex;
 61
 62	struct usb_interface		*intf;
 63	int (*notify_client)(struct usb_interface *intf,
 64			     struct xhci_sideband_event *evt);
 65};
 66
 67struct xhci_sideband *
 68xhci_sideband_register(struct usb_interface *intf, enum xhci_sideband_type type,
 69		       int (*notify_client)(struct usb_interface *intf,
 70				    struct xhci_sideband_event *evt));
 71void
 72xhci_sideband_unregister(struct xhci_sideband *sb);
 73int
 74xhci_sideband_add_endpoint(struct xhci_sideband *sb,
 75			   struct usb_host_endpoint *host_ep);
 76int
 77xhci_sideband_remove_endpoint(struct xhci_sideband *sb,
 78			      struct usb_host_endpoint *host_ep);
 79int
 80xhci_sideband_stop_endpoint(struct xhci_sideband *sb,
 81			    struct usb_host_endpoint *host_ep);
 82struct sg_table *
 83xhci_sideband_get_endpoint_buffer(struct xhci_sideband *sb,
 84				  struct usb_host_endpoint *host_ep);
 85struct sg_table *
 86xhci_sideband_get_event_buffer(struct xhci_sideband *sb);
 87
 88#if IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND)
 89bool xhci_sideband_check(struct usb_hcd *hcd);
 90#else
 91static inline bool xhci_sideband_check(struct usb_hcd *hcd)
 92{ return false; }
 93#endif /* IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND) */
 94
 95int
 96xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg,
 97				 bool ip_autoclear, u32 imod_interval, int intr_num);
 98void
 99xhci_sideband_remove_interrupter(struct xhci_sideband *sb);
100int
101xhci_sideband_interrupter_id(struct xhci_sideband *sb);
102
103#if IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND)
104void xhci_sideband_notify_ep_ring_free(struct xhci_sideband *sb,
105				       unsigned int ep_index);
106#else
107static inline void xhci_sideband_notify_ep_ring_free(struct xhci_sideband *sb,
108						     unsigned int ep_index)
109{ }
110#endif /* IS_ENABLED(CONFIG_USB_XHCI_SIDEBAND) */
111#endif /* __LINUX_XHCI_SIDEBAND_H */