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