1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2
3 /*
4 * Xen para-virtual sound device
5 *
6 * Copyright (C) 2016-2018 EPAM Systems Inc.
7 *
8 * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
9 */
10
11 #ifndef __XEN_SND_FRONT_EVTCHNL_H
12 #define __XEN_SND_FRONT_EVTCHNL_H
13
14 #include <xen/interface/io/sndif.h>
15
16 struct xen_snd_front_info;
17
18 /* Timeout in ms to wait for backend to respond. */
19 #define VSND_WAIT_BACK_MS 3000
20
21 enum xen_snd_front_evtchnl_state {
22 EVTCHNL_STATE_DISCONNECTED,
23 EVTCHNL_STATE_CONNECTED,
24 };
25
26 enum xen_snd_front_evtchnl_type {
27 EVTCHNL_TYPE_REQ,
28 EVTCHNL_TYPE_EVT,
29 };
30
31 struct xen_snd_front_evtchnl {
32 struct xen_snd_front_info *front_info;
33 int gref;
34 int port;
35 int irq;
36 int index;
37 /* State of the event channel. */
38 enum xen_snd_front_evtchnl_state state;
39 enum xen_snd_front_evtchnl_type type;
40 /* Either response id or incoming event id. */
41 u16 evt_id;
42 /* Next request id or next expected event id. */
43 u16 evt_next_id;
44 /* Shared ring access lock. */
45 struct mutex ring_io_lock;
46 union {
47 struct {
48 struct xen_sndif_front_ring ring;
49 struct completion completion;
50 /* Serializer for backend IO: request/response. */
51 struct mutex req_io_lock;
52
53 /* Latest response status. */
54 int resp_status;
55 union {
56 struct xensnd_query_hw_param hw_param;
57 } resp;
58 } req;
59 struct {
60 struct xensnd_event_page *page;
61 /* This is needed to handle XENSND_EVT_CUR_POS event. */
62 struct snd_pcm_substream *substream;
63 } evt;
64 } u;
65 };
66
67 struct xen_snd_front_evtchnl_pair {
68 struct xen_snd_front_evtchnl req;
69 struct xen_snd_front_evtchnl evt;
70 };
71
72 int xen_snd_front_evtchnl_create_all(struct xen_snd_front_info *front_info,
73 int num_streams);
74
75 void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info);
76
77 int xen_snd_front_evtchnl_publish_all(struct xen_snd_front_info *front_info);
78
79 void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *evtchnl);
80
81 void xen_snd_front_evtchnl_pair_set_connected(struct xen_snd_front_evtchnl_pair *evt_pair,
82 bool is_connected);
83
84 void xen_snd_front_evtchnl_pair_clear(struct xen_snd_front_evtchnl_pair *evt_pair);
85
86 #endif /* __XEN_SND_FRONT_EVTCHNL_H */
87
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