xref: /OK3568_Linux_fs/kernel/sound/xen/xen_snd_front_evtchnl.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2*4882a593Smuzhiyun 
3*4882a593Smuzhiyun /*
4*4882a593Smuzhiyun  * Xen para-virtual sound device
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Copyright (C) 2016-2018 EPAM Systems Inc.
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
9*4882a593Smuzhiyun  */
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #ifndef __XEN_SND_FRONT_EVTCHNL_H
12*4882a593Smuzhiyun #define __XEN_SND_FRONT_EVTCHNL_H
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun #include <xen/interface/io/sndif.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun struct xen_snd_front_info;
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun #ifndef GRANT_INVALID_REF
19*4882a593Smuzhiyun /*
20*4882a593Smuzhiyun  * FIXME: usage of grant reference 0 as invalid grant reference:
21*4882a593Smuzhiyun  * grant reference 0 is valid, but never exposed to a PV driver,
22*4882a593Smuzhiyun  * because of the fact it is already in use/reserved by the PV console.
23*4882a593Smuzhiyun  */
24*4882a593Smuzhiyun #define GRANT_INVALID_REF	0
25*4882a593Smuzhiyun #endif
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun /* Timeout in ms to wait for backend to respond. */
28*4882a593Smuzhiyun #define VSND_WAIT_BACK_MS	3000
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun enum xen_snd_front_evtchnl_state {
31*4882a593Smuzhiyun 	EVTCHNL_STATE_DISCONNECTED,
32*4882a593Smuzhiyun 	EVTCHNL_STATE_CONNECTED,
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun enum xen_snd_front_evtchnl_type {
36*4882a593Smuzhiyun 	EVTCHNL_TYPE_REQ,
37*4882a593Smuzhiyun 	EVTCHNL_TYPE_EVT,
38*4882a593Smuzhiyun };
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun struct xen_snd_front_evtchnl {
41*4882a593Smuzhiyun 	struct xen_snd_front_info *front_info;
42*4882a593Smuzhiyun 	int gref;
43*4882a593Smuzhiyun 	int port;
44*4882a593Smuzhiyun 	int irq;
45*4882a593Smuzhiyun 	int index;
46*4882a593Smuzhiyun 	/* State of the event channel. */
47*4882a593Smuzhiyun 	enum xen_snd_front_evtchnl_state state;
48*4882a593Smuzhiyun 	enum xen_snd_front_evtchnl_type type;
49*4882a593Smuzhiyun 	/* Either response id or incoming event id. */
50*4882a593Smuzhiyun 	u16 evt_id;
51*4882a593Smuzhiyun 	/* Next request id or next expected event id. */
52*4882a593Smuzhiyun 	u16 evt_next_id;
53*4882a593Smuzhiyun 	/* Shared ring access lock. */
54*4882a593Smuzhiyun 	struct mutex ring_io_lock;
55*4882a593Smuzhiyun 	union {
56*4882a593Smuzhiyun 		struct {
57*4882a593Smuzhiyun 			struct xen_sndif_front_ring ring;
58*4882a593Smuzhiyun 			struct completion completion;
59*4882a593Smuzhiyun 			/* Serializer for backend IO: request/response. */
60*4882a593Smuzhiyun 			struct mutex req_io_lock;
61*4882a593Smuzhiyun 
62*4882a593Smuzhiyun 			/* Latest response status. */
63*4882a593Smuzhiyun 			int resp_status;
64*4882a593Smuzhiyun 			union {
65*4882a593Smuzhiyun 				struct xensnd_query_hw_param hw_param;
66*4882a593Smuzhiyun 			} resp;
67*4882a593Smuzhiyun 		} req;
68*4882a593Smuzhiyun 		struct {
69*4882a593Smuzhiyun 			struct xensnd_event_page *page;
70*4882a593Smuzhiyun 			/* This is needed to handle XENSND_EVT_CUR_POS event. */
71*4882a593Smuzhiyun 			struct snd_pcm_substream *substream;
72*4882a593Smuzhiyun 		} evt;
73*4882a593Smuzhiyun 	} u;
74*4882a593Smuzhiyun };
75*4882a593Smuzhiyun 
76*4882a593Smuzhiyun struct xen_snd_front_evtchnl_pair {
77*4882a593Smuzhiyun 	struct xen_snd_front_evtchnl req;
78*4882a593Smuzhiyun 	struct xen_snd_front_evtchnl evt;
79*4882a593Smuzhiyun };
80*4882a593Smuzhiyun 
81*4882a593Smuzhiyun int xen_snd_front_evtchnl_create_all(struct xen_snd_front_info *front_info,
82*4882a593Smuzhiyun 				     int num_streams);
83*4882a593Smuzhiyun 
84*4882a593Smuzhiyun void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info);
85*4882a593Smuzhiyun 
86*4882a593Smuzhiyun int xen_snd_front_evtchnl_publish_all(struct xen_snd_front_info *front_info);
87*4882a593Smuzhiyun 
88*4882a593Smuzhiyun void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *evtchnl);
89*4882a593Smuzhiyun 
90*4882a593Smuzhiyun void xen_snd_front_evtchnl_pair_set_connected(struct xen_snd_front_evtchnl_pair *evt_pair,
91*4882a593Smuzhiyun 					      bool is_connected);
92*4882a593Smuzhiyun 
93*4882a593Smuzhiyun void xen_snd_front_evtchnl_pair_clear(struct xen_snd_front_evtchnl_pair *evt_pair);
94*4882a593Smuzhiyun 
95*4882a593Smuzhiyun #endif /* __XEN_SND_FRONT_EVTCHNL_H */
96