LXR linux/drivers/gpu/drm/xen/xen_drm_front

   1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
   2
   3/*
   4 *  Xen para-virtual DRM device
   5 *
   6 * Copyright (C) 2016-2018 EPAM Systems Inc.
   7 *
   8 * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
   9 */
  10
  11#ifndef __XEN_DRM_FRONT_EVTCHNL_H_
  12#define __XEN_DRM_FRONT_EVTCHNL_H_
  13
  14#include <linux/completion.h>
  15#include <linux/types.h>
  16
  17#include <xen/interface/io/ring.h>
  18#include <xen/interface/io/displif.h>
  19
  20/*
  21 * All operations which are not connector oriented use this ctrl event channel,
  22 * e.g. fb_attach/destroy which belong to a DRM device, not to a CRTC.
  23 */
  24#define GENERIC_OP_EVT_CHNL     0
  25
  26enum xen_drm_front_evtchnl_state {
  27        EVTCHNL_STATE_DISCONNECTED,
  28        EVTCHNL_STATE_CONNECTED,
  29};
  30
  31enum xen_drm_front_evtchnl_type {
  32        EVTCHNL_TYPE_REQ,
  33        EVTCHNL_TYPE_EVT,
  34};
  35
  36struct xen_drm_front_drm_info;
  37
  38struct xen_drm_front_evtchnl {
  39        struct xen_drm_front_info *front_info;
  40        int gref;
  41        int port;
  42        int irq;
  43        int index;
  44        enum xen_drm_front_evtchnl_state state;
  45        enum xen_drm_front_evtchnl_type type;
  46        /* either response id or incoming event id */
  47        u16 evt_id;
  48        /* next request id or next expected event id */
  49        u16 evt_next_id;
  50        union {
  51                struct {
  52                        struct xen_displif_front_ring ring;
  53                        struct completion completion;
  54                        /* latest response status */
  55                        int resp_status;
  56                        /* serializer for backend IO: request/response */
  57                        struct mutex req_io_lock;
  58                } req;
  59                struct {
  60                        struct xendispl_event_page *page;
  61                } evt;
  62        } u;
  63};
  64
  65struct xen_drm_front_evtchnl_pair {
  66        struct xen_drm_front_evtchnl req;
  67        struct xen_drm_front_evtchnl evt;
  68};
  69
  70int xen_drm_front_evtchnl_create_all(struct xen_drm_front_info *front_info);
  71
  72int xen_drm_front_evtchnl_publish_all(struct xen_drm_front_info *front_info);
  73
  74void xen_drm_front_evtchnl_flush(struct xen_drm_front_evtchnl *evtchnl);
  75
  76void xen_drm_front_evtchnl_set_state(struct xen_drm_front_info *front_info,
  77                                     enum xen_drm_front_evtchnl_state state);
  78
  79void xen_drm_front_evtchnl_free_all(struct xen_drm_front_info *front_info);
  80
  81#endif /* __XEN_DRM_FRONT_EVTCHNL_H_ */
  82