1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * virtio-snd: Virtio sound device
4 * Copyright (C) 2021 OpenSynergy GmbH
5 */
6 #ifndef VIRTIO_SND_PCM_H
7 #define VIRTIO_SND_PCM_H
8
9 #include <linux/atomic.h>
10 #include <linux/virtio_config.h>
11 #include <sound/pcm.h>
12 #include <sound/pcm-indirect.h>
13
14 struct virtio_pcm;
15 struct virtio_pcm_msg;
16
17 /**
18 * struct virtio_pcm_substream - VirtIO PCM substream.
19 * @snd: VirtIO sound device.
20 * @nid: Function group node identifier.
21 * @sid: Stream identifier.
22 * @direction: Stream data flow direction (SNDRV_PCM_STREAM_XXX).
23 * @features: Stream VirtIO feature bit map (1 << VIRTIO_SND_PCM_F_XXX).
24 * @substream: Kernel ALSA substream.
25 * @pcm_indirect: Kernel indirect pcm structure.
26 * @hw: Kernel ALSA substream hardware descriptor.
27 * @elapsed_period: Kernel work to handle the elapsed period state.
28 * @lock: Spinlock that protects fields shared by interrupt handlers and
29 * substream operators.
30 * @buffer_bytes: Current buffer size in bytes.
31 * @hw_ptr: Substream hardware pointer value in bytes [0 ... buffer_bytes).
32 * @xfer_enabled: Data transfer state (0 - off, 1 - on).
33 * @xfer_xrun: Data underflow/overflow state (0 - no xrun, 1 - xrun).
34 * @stopped: True if the substream is stopped and must be released on the device
35 * side.
36 * @suspended: True if the substream is suspended and must be reconfigured on
37 * the device side at resume.
38 * @msgs: Allocated I/O messages.
39 * @nmsgs: Number of allocated I/O messages.
40 * @msg_last_enqueued: Index of the last I/O message added to the virtqueue.
41 * @msg_count: Number of pending I/O messages in the virtqueue.
42 * @msg_empty: Notify when msg_count is zero.
43 */
44 struct virtio_pcm_substream {
45 struct virtio_snd *snd;
46 u32 nid;
47 u32 sid;
48 u32 direction;
49 u32 features;
50 struct snd_pcm_substream *substream;
51 struct snd_pcm_indirect pcm_indirect;
52 struct snd_pcm_hardware hw;
53 struct work_struct elapsed_period;
54 spinlock_t lock;
55 size_t buffer_bytes;
56 size_t hw_ptr;
57 bool xfer_enabled;
58 bool xfer_xrun;
59 bool stopped;
60 bool suspended;
61 struct virtio_pcm_msg **msgs;
62 unsigned int nmsgs;
63 unsigned int msg_count;
64 wait_queue_head_t msg_empty;
65 };
66
67 /**
68 * struct virtio_pcm_stream - VirtIO PCM stream.
69 * @substreams: VirtIO substreams belonging to the stream.
70 * @nsubstreams: Number of substreams.
71 * @chmaps: Kernel channel maps belonging to the stream.
72 * @nchmaps: Number of channel maps.
73 */
74 struct virtio_pcm_stream {
75 struct virtio_pcm_substream **substreams;
76 u32 nsubstreams;
77 struct snd_pcm_chmap_elem *chmaps;
78 u32 nchmaps;
79 };
80
81 /**
82 * struct virtio_pcm - VirtIO PCM device.
83 * @list: VirtIO PCM list entry.
84 * @nid: Function group node identifier.
85 * @pcm: Kernel PCM device.
86 * @streams: VirtIO PCM streams (playback and capture).
87 */
88 struct virtio_pcm {
89 struct list_head list;
90 u32 nid;
91 struct snd_pcm *pcm;
92 struct virtio_pcm_stream streams[SNDRV_PCM_STREAM_LAST + 1];
93 };
94
95 extern const struct snd_pcm_ops virtsnd_pcm_ops[];
96
97 int virtsnd_pcm_validate(struct virtio_device *vdev);
98
99 int virtsnd_pcm_parse_cfg(struct virtio_snd *snd);
100
101 int virtsnd_pcm_build_devs(struct virtio_snd *snd);
102
103 void virtsnd_pcm_event(struct virtio_snd *snd, struct virtio_snd_event *event);
104
105 void virtsnd_pcm_tx_notify_cb(struct virtqueue *vqueue);
106
107 void virtsnd_pcm_rx_notify_cb(struct virtqueue *vqueue);
108
109 struct virtio_pcm *virtsnd_pcm_find(struct virtio_snd *snd, u32 nid);
110
111 struct virtio_pcm *virtsnd_pcm_find_or_create(struct virtio_snd *snd, u32 nid);
112
113 struct virtio_snd_msg *
114 virtsnd_pcm_ctl_msg_alloc(struct virtio_pcm_substream *vss,
115 unsigned int command, gfp_t gfp);
116
117 int virtsnd_pcm_msg_alloc(struct virtio_pcm_substream *vss,
118 unsigned int periods, unsigned int period_bytes);
119
120 void virtsnd_pcm_msg_free(struct virtio_pcm_substream *vss);
121
122 int virtsnd_pcm_msg_send(struct virtio_pcm_substream *vss, unsigned long offset,
123 unsigned long bytes);
124
125 unsigned int virtsnd_pcm_msg_pending_num(struct virtio_pcm_substream *vss);
126
127 #endif /* VIRTIO_SND_PCM_H */
128
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