diff options
Diffstat (limited to 'sound/virtio')
-rw-r--r-- | sound/virtio/Kconfig | 10 | ||||
-rw-r--r-- | sound/virtio/Makefile | 13 | ||||
-rw-r--r-- | sound/virtio/virtio_card.c | 439 | ||||
-rw-r--r-- | sound/virtio/virtio_card.h | 111 | ||||
-rw-r--r-- | sound/virtio/virtio_chmap.c | 219 | ||||
-rw-r--r-- | sound/virtio/virtio_ctl_msg.c | 310 | ||||
-rw-r--r-- | sound/virtio/virtio_ctl_msg.h | 78 | ||||
-rw-r--r-- | sound/virtio/virtio_jack.c | 233 | ||||
-rw-r--r-- | sound/virtio/virtio_pcm.c | 513 | ||||
-rw-r--r-- | sound/virtio/virtio_pcm.h | 124 | ||||
-rw-r--r-- | sound/virtio/virtio_pcm_msg.c | 413 | ||||
-rw-r--r-- | sound/virtio/virtio_pcm_ops.c | 464 |
12 files changed, 2927 insertions, 0 deletions
diff --git a/sound/virtio/Kconfig b/sound/virtio/Kconfig new file mode 100644 index 0000000000..094cba24ee --- /dev/null +++ b/sound/virtio/Kconfig @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0+ +# Sound card driver for virtio + +config SND_VIRTIO + tristate "Virtio sound driver" + depends on VIRTIO + select SND_PCM + select SND_JACK + help + This is the virtual sound driver for virtio. Say Y or M. diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile new file mode 100644 index 0000000000..2742bddb88 --- /dev/null +++ b/sound/virtio/Makefile @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0+ + +obj-$(CONFIG_SND_VIRTIO) += virtio_snd.o + +virtio_snd-objs := \ + virtio_card.o \ + virtio_chmap.o \ + virtio_ctl_msg.o \ + virtio_jack.o \ + virtio_pcm.o \ + virtio_pcm_msg.o \ + virtio_pcm_ops.o + diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c new file mode 100644 index 0000000000..e2847c040f --- /dev/null +++ b/sound/virtio/virtio_card.c @@ -0,0 +1,439 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/virtio_config.h> +#include <sound/initval.h> +#include <uapi/linux/virtio_ids.h> + +#include "virtio_card.h" + +u32 virtsnd_msg_timeout_ms = MSEC_PER_SEC; +module_param_named(msg_timeout_ms, virtsnd_msg_timeout_ms, uint, 0644); +MODULE_PARM_DESC(msg_timeout_ms, "Message completion timeout in milliseconds"); + +static void virtsnd_remove(struct virtio_device *vdev); + +/** + * virtsnd_event_send() - Add an event to the event queue. + * @vqueue: Underlying event virtqueue. + * @event: Event. + * @notify: Indicates whether or not to send a notification to the device. + * @gfp: Kernel flags for memory allocation. + * + * Context: Any context. + */ +static void virtsnd_event_send(struct virtqueue *vqueue, + struct virtio_snd_event *event, bool notify, + gfp_t gfp) +{ + struct scatterlist sg; + struct scatterlist *psgs[1] = { &sg }; + + /* reset event content */ + memset(event, 0, sizeof(*event)); + + sg_init_one(&sg, event, sizeof(*event)); + + if (virtqueue_add_sgs(vqueue, psgs, 0, 1, event, gfp) || !notify) + return; + + if (virtqueue_kick_prepare(vqueue)) + virtqueue_notify(vqueue); +} + +/** + * virtsnd_event_dispatch() - Dispatch an event from the device side. + * @snd: VirtIO sound device. + * @event: VirtIO sound event. + * + * Context: Any context. + */ +static void virtsnd_event_dispatch(struct virtio_snd *snd, + struct virtio_snd_event *event) +{ + switch (le32_to_cpu(event->hdr.code)) { + case VIRTIO_SND_EVT_JACK_CONNECTED: + case VIRTIO_SND_EVT_JACK_DISCONNECTED: + virtsnd_jack_event(snd, event); + break; + case VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED: + case VIRTIO_SND_EVT_PCM_XRUN: + virtsnd_pcm_event(snd, event); + break; + } +} + +/** + * virtsnd_event_notify_cb() - Dispatch all reported events from the event queue. + * @vqueue: Underlying event virtqueue. + * + * This callback function is called upon a vring interrupt request from the + * device. + * + * Context: Interrupt context. + */ +static void virtsnd_event_notify_cb(struct virtqueue *vqueue) +{ + struct virtio_snd *snd = vqueue->vdev->priv; + struct virtio_snd_queue *queue = virtsnd_event_queue(snd); + struct virtio_snd_event *event; + u32 length; + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + do { + virtqueue_disable_cb(vqueue); + while ((event = virtqueue_get_buf(vqueue, &length))) { + virtsnd_event_dispatch(snd, event); + virtsnd_event_send(vqueue, event, true, GFP_ATOMIC); + } + if (unlikely(virtqueue_is_broken(vqueue))) + break; + } while (!virtqueue_enable_cb(vqueue)); + spin_unlock_irqrestore(&queue->lock, flags); +} + +/** + * virtsnd_find_vqs() - Enumerate and initialize all virtqueues. + * @snd: VirtIO sound device. + * + * After calling this function, the event queue is disabled. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_find_vqs(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + static vq_callback_t *callbacks[VIRTIO_SND_VQ_MAX] = { + [VIRTIO_SND_VQ_CONTROL] = virtsnd_ctl_notify_cb, + [VIRTIO_SND_VQ_EVENT] = virtsnd_event_notify_cb, + [VIRTIO_SND_VQ_TX] = virtsnd_pcm_tx_notify_cb, + [VIRTIO_SND_VQ_RX] = virtsnd_pcm_rx_notify_cb + }; + static const char *names[VIRTIO_SND_VQ_MAX] = { + [VIRTIO_SND_VQ_CONTROL] = "virtsnd-ctl", + [VIRTIO_SND_VQ_EVENT] = "virtsnd-event", + [VIRTIO_SND_VQ_TX] = "virtsnd-tx", + [VIRTIO_SND_VQ_RX] = "virtsnd-rx" + }; + struct virtqueue *vqs[VIRTIO_SND_VQ_MAX] = { 0 }; + unsigned int i; + unsigned int n; + int rc; + + rc = virtio_find_vqs(vdev, VIRTIO_SND_VQ_MAX, vqs, callbacks, names, + NULL); + if (rc) { + dev_err(&vdev->dev, "failed to initialize virtqueues\n"); + return rc; + } + + for (i = 0; i < VIRTIO_SND_VQ_MAX; ++i) + snd->queues[i].vqueue = vqs[i]; + + /* Allocate events and populate the event queue */ + virtqueue_disable_cb(vqs[VIRTIO_SND_VQ_EVENT]); + + n = virtqueue_get_vring_size(vqs[VIRTIO_SND_VQ_EVENT]); + + snd->event_msgs = kmalloc_array(n, sizeof(*snd->event_msgs), + GFP_KERNEL); + if (!snd->event_msgs) + return -ENOMEM; + + for (i = 0; i < n; ++i) + virtsnd_event_send(vqs[VIRTIO_SND_VQ_EVENT], + &snd->event_msgs[i], false, GFP_KERNEL); + + return 0; +} + +/** + * virtsnd_enable_event_vq() - Enable the event virtqueue. + * @snd: VirtIO sound device. + * + * Context: Any context. + */ +static void virtsnd_enable_event_vq(struct virtio_snd *snd) +{ + struct virtio_snd_queue *queue = virtsnd_event_queue(snd); + + if (!virtqueue_enable_cb(queue->vqueue)) + virtsnd_event_notify_cb(queue->vqueue); +} + +/** + * virtsnd_disable_event_vq() - Disable the event virtqueue. + * @snd: VirtIO sound device. + * + * Context: Any context. + */ +static void virtsnd_disable_event_vq(struct virtio_snd *snd) +{ + struct virtio_snd_queue *queue = virtsnd_event_queue(snd); + struct virtio_snd_event *event; + u32 length; + unsigned long flags; + + if (queue->vqueue) { + spin_lock_irqsave(&queue->lock, flags); + virtqueue_disable_cb(queue->vqueue); + while ((event = virtqueue_get_buf(queue->vqueue, &length))) + virtsnd_event_dispatch(snd, event); + spin_unlock_irqrestore(&queue->lock, flags); + } +} + +/** + * virtsnd_build_devs() - Read configuration and build ALSA devices. + * @snd: VirtIO sound device. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_build_devs(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + struct device *dev = &vdev->dev; + int rc; + + rc = snd_card_new(dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1, + THIS_MODULE, 0, &snd->card); + if (rc < 0) + return rc; + + snd->card->private_data = snd; + + strscpy(snd->card->driver, VIRTIO_SND_CARD_DRIVER, + sizeof(snd->card->driver)); + strscpy(snd->card->shortname, VIRTIO_SND_CARD_NAME, + sizeof(snd->card->shortname)); + if (dev->parent->bus) + snprintf(snd->card->longname, sizeof(snd->card->longname), + VIRTIO_SND_CARD_NAME " at %s/%s/%s", + dev->parent->bus->name, dev_name(dev->parent), + dev_name(dev)); + else + snprintf(snd->card->longname, sizeof(snd->card->longname), + VIRTIO_SND_CARD_NAME " at %s/%s", + dev_name(dev->parent), dev_name(dev)); + + rc = virtsnd_jack_parse_cfg(snd); + if (rc) + return rc; + + rc = virtsnd_pcm_parse_cfg(snd); + if (rc) + return rc; + + rc = virtsnd_chmap_parse_cfg(snd); + if (rc) + return rc; + + if (snd->njacks) { + rc = virtsnd_jack_build_devs(snd); + if (rc) + return rc; + } + + if (snd->nsubstreams) { + rc = virtsnd_pcm_build_devs(snd); + if (rc) + return rc; + } + + if (snd->nchmaps) { + rc = virtsnd_chmap_build_devs(snd); + if (rc) + return rc; + } + + return snd_card_register(snd->card); +} + +/** + * virtsnd_validate() - Validate if the device can be started. + * @vdev: VirtIO parent device. + * + * Context: Any context. + * Return: 0 on success, -EINVAL on failure. + */ +static int virtsnd_validate(struct virtio_device *vdev) +{ + if (!vdev->config->get) { + dev_err(&vdev->dev, "configuration access disabled\n"); + return -EINVAL; + } + + if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) { + dev_err(&vdev->dev, + "device does not comply with spec version 1.x\n"); + return -EINVAL; + } + + if (!virtsnd_msg_timeout_ms) { + dev_err(&vdev->dev, "msg_timeout_ms value cannot be zero\n"); + return -EINVAL; + } + + if (virtsnd_pcm_validate(vdev)) + return -EINVAL; + + return 0; +} + +/** + * virtsnd_probe() - Create and initialize the device. + * @vdev: VirtIO parent device. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_probe(struct virtio_device *vdev) +{ + struct virtio_snd *snd; + unsigned int i; + int rc; + + snd = devm_kzalloc(&vdev->dev, sizeof(*snd), GFP_KERNEL); + if (!snd) + return -ENOMEM; + + snd->vdev = vdev; + INIT_LIST_HEAD(&snd->ctl_msgs); + INIT_LIST_HEAD(&snd->pcm_list); + + vdev->priv = snd; + + for (i = 0; i < VIRTIO_SND_VQ_MAX; ++i) + spin_lock_init(&snd->queues[i].lock); + + rc = virtsnd_find_vqs(snd); + if (rc) + goto on_exit; + + virtio_device_ready(vdev); + + rc = virtsnd_build_devs(snd); + if (rc) + goto on_exit; + + virtsnd_enable_event_vq(snd); + +on_exit: + if (rc) + virtsnd_remove(vdev); + + return rc; +} + +/** + * virtsnd_remove() - Remove VirtIO and ALSA devices. + * @vdev: VirtIO parent device. + * + * Context: Any context that permits to sleep. + */ +static void virtsnd_remove(struct virtio_device *vdev) +{ + struct virtio_snd *snd = vdev->priv; + unsigned int i; + + virtsnd_disable_event_vq(snd); + virtsnd_ctl_msg_cancel_all(snd); + + if (snd->card) + snd_card_free(snd->card); + + vdev->config->del_vqs(vdev); + virtio_reset_device(vdev); + + for (i = 0; snd->substreams && i < snd->nsubstreams; ++i) { + struct virtio_pcm_substream *vss = &snd->substreams[i]; + + cancel_work_sync(&vss->elapsed_period); + virtsnd_pcm_msg_free(vss); + } + + kfree(snd->event_msgs); +} + +#ifdef CONFIG_PM_SLEEP +/** + * virtsnd_freeze() - Suspend device. + * @vdev: VirtIO parent device. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_freeze(struct virtio_device *vdev) +{ + struct virtio_snd *snd = vdev->priv; + unsigned int i; + + virtsnd_disable_event_vq(snd); + virtsnd_ctl_msg_cancel_all(snd); + + vdev->config->del_vqs(vdev); + virtio_reset_device(vdev); + + for (i = 0; i < snd->nsubstreams; ++i) + cancel_work_sync(&snd->substreams[i].elapsed_period); + + kfree(snd->event_msgs); + snd->event_msgs = NULL; + + return 0; +} + +/** + * virtsnd_restore() - Resume device. + * @vdev: VirtIO parent device. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_restore(struct virtio_device *vdev) +{ + struct virtio_snd *snd = vdev->priv; + int rc; + + rc = virtsnd_find_vqs(snd); + if (rc) + return rc; + + virtio_device_ready(vdev); + + virtsnd_enable_event_vq(snd); + + return 0; +} +#endif /* CONFIG_PM_SLEEP */ + +static const struct virtio_device_id id_table[] = { + { VIRTIO_ID_SOUND, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct virtio_driver virtsnd_driver = { + .driver.name = KBUILD_MODNAME, + .driver.owner = THIS_MODULE, + .id_table = id_table, + .validate = virtsnd_validate, + .probe = virtsnd_probe, + .remove = virtsnd_remove, +#ifdef CONFIG_PM_SLEEP + .freeze = virtsnd_freeze, + .restore = virtsnd_restore, +#endif +}; + +module_virtio_driver(virtsnd_driver); + +MODULE_DEVICE_TABLE(virtio, id_table); +MODULE_DESCRIPTION("Virtio sound card driver"); +MODULE_LICENSE("GPL"); diff --git a/sound/virtio/virtio_card.h b/sound/virtio/virtio_card.h new file mode 100644 index 0000000000..86ef394189 --- /dev/null +++ b/sound/virtio/virtio_card.h @@ -0,0 +1,111 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#ifndef VIRTIO_SND_CARD_H +#define VIRTIO_SND_CARD_H + +#include <linux/slab.h> +#include <linux/virtio.h> +#include <sound/core.h> +#include <uapi/linux/virtio_snd.h> + +#include "virtio_ctl_msg.h" +#include "virtio_pcm.h" + +#define VIRTIO_SND_CARD_DRIVER "virtio-snd" +#define VIRTIO_SND_CARD_NAME "VirtIO SoundCard" +#define VIRTIO_SND_PCM_NAME "VirtIO PCM" + +struct virtio_jack; +struct virtio_pcm_substream; + +/** + * struct virtio_snd_queue - Virtqueue wrapper structure. + * @lock: Used to synchronize access to a virtqueue. + * @vqueue: Underlying virtqueue. + */ +struct virtio_snd_queue { + spinlock_t lock; + struct virtqueue *vqueue; +}; + +/** + * struct virtio_snd - VirtIO sound card device. + * @vdev: Underlying virtio device. + * @queues: Virtqueue wrappers. + * @card: ALSA sound card. + * @ctl_msgs: Pending control request list. + * @event_msgs: Device events. + * @pcm_list: VirtIO PCM device list. + * @jacks: VirtIO jacks. + * @njacks: Number of jacks. + * @substreams: VirtIO PCM substreams. + * @nsubstreams: Number of PCM substreams. + * @chmaps: VirtIO channel maps. + * @nchmaps: Number of channel maps. + */ +struct virtio_snd { + struct virtio_device *vdev; + struct virtio_snd_queue queues[VIRTIO_SND_VQ_MAX]; + struct snd_card *card; + struct list_head ctl_msgs; + struct virtio_snd_event *event_msgs; + struct list_head pcm_list; + struct virtio_jack *jacks; + u32 njacks; + struct virtio_pcm_substream *substreams; + u32 nsubstreams; + struct virtio_snd_chmap_info *chmaps; + u32 nchmaps; +}; + +/* Message completion timeout in milliseconds (module parameter). */ +extern u32 virtsnd_msg_timeout_ms; + +static inline struct virtio_snd_queue * +virtsnd_control_queue(struct virtio_snd *snd) +{ + return &snd->queues[VIRTIO_SND_VQ_CONTROL]; +} + +static inline struct virtio_snd_queue * +virtsnd_event_queue(struct virtio_snd *snd) +{ + return &snd->queues[VIRTIO_SND_VQ_EVENT]; +} + +static inline struct virtio_snd_queue * +virtsnd_tx_queue(struct virtio_snd *snd) +{ + return &snd->queues[VIRTIO_SND_VQ_TX]; +} + +static inline struct virtio_snd_queue * +virtsnd_rx_queue(struct virtio_snd *snd) +{ + return &snd->queues[VIRTIO_SND_VQ_RX]; +} + +static inline struct virtio_snd_queue * +virtsnd_pcm_queue(struct virtio_pcm_substream *vss) +{ + if (vss->direction == SNDRV_PCM_STREAM_PLAYBACK) + return virtsnd_tx_queue(vss->snd); + else + return virtsnd_rx_queue(vss->snd); +} + +int virtsnd_jack_parse_cfg(struct virtio_snd *snd); + +int virtsnd_jack_build_devs(struct virtio_snd *snd); + +void virtsnd_jack_event(struct virtio_snd *snd, + struct virtio_snd_event *event); + +int virtsnd_chmap_parse_cfg(struct virtio_snd *snd); + +int virtsnd_chmap_build_devs(struct virtio_snd *snd); + +#endif /* VIRTIO_SND_CARD_H */ diff --git a/sound/virtio/virtio_chmap.c b/sound/virtio/virtio_chmap.c new file mode 100644 index 0000000000..5bc924933a --- /dev/null +++ b/sound/virtio/virtio_chmap.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <linux/virtio_config.h> + +#include "virtio_card.h" + +/* VirtIO->ALSA channel position map */ +static const u8 g_v2a_position_map[] = { + [VIRTIO_SND_CHMAP_NONE] = SNDRV_CHMAP_UNKNOWN, + [VIRTIO_SND_CHMAP_NA] = SNDRV_CHMAP_NA, + [VIRTIO_SND_CHMAP_MONO] = SNDRV_CHMAP_MONO, + [VIRTIO_SND_CHMAP_FL] = SNDRV_CHMAP_FL, + [VIRTIO_SND_CHMAP_FR] = SNDRV_CHMAP_FR, + [VIRTIO_SND_CHMAP_RL] = SNDRV_CHMAP_RL, + [VIRTIO_SND_CHMAP_RR] = SNDRV_CHMAP_RR, + [VIRTIO_SND_CHMAP_FC] = SNDRV_CHMAP_FC, + [VIRTIO_SND_CHMAP_LFE] = SNDRV_CHMAP_LFE, + [VIRTIO_SND_CHMAP_SL] = SNDRV_CHMAP_SL, + [VIRTIO_SND_CHMAP_SR] = SNDRV_CHMAP_SR, + [VIRTIO_SND_CHMAP_RC] = SNDRV_CHMAP_RC, + [VIRTIO_SND_CHMAP_FLC] = SNDRV_CHMAP_FLC, + [VIRTIO_SND_CHMAP_FRC] = SNDRV_CHMAP_FRC, + [VIRTIO_SND_CHMAP_RLC] = SNDRV_CHMAP_RLC, + [VIRTIO_SND_CHMAP_RRC] = SNDRV_CHMAP_RRC, + [VIRTIO_SND_CHMAP_FLW] = SNDRV_CHMAP_FLW, + [VIRTIO_SND_CHMAP_FRW] = SNDRV_CHMAP_FRW, + [VIRTIO_SND_CHMAP_FLH] = SNDRV_CHMAP_FLH, + [VIRTIO_SND_CHMAP_FCH] = SNDRV_CHMAP_FCH, + [VIRTIO_SND_CHMAP_FRH] = SNDRV_CHMAP_FRH, + [VIRTIO_SND_CHMAP_TC] = SNDRV_CHMAP_TC, + [VIRTIO_SND_CHMAP_TFL] = SNDRV_CHMAP_TFL, + [VIRTIO_SND_CHMAP_TFR] = SNDRV_CHMAP_TFR, + [VIRTIO_SND_CHMAP_TFC] = SNDRV_CHMAP_TFC, + [VIRTIO_SND_CHMAP_TRL] = SNDRV_CHMAP_TRL, + [VIRTIO_SND_CHMAP_TRR] = SNDRV_CHMAP_TRR, + [VIRTIO_SND_CHMAP_TRC] = SNDRV_CHMAP_TRC, + [VIRTIO_SND_CHMAP_TFLC] = SNDRV_CHMAP_TFLC, + [VIRTIO_SND_CHMAP_TFRC] = SNDRV_CHMAP_TFRC, + [VIRTIO_SND_CHMAP_TSL] = SNDRV_CHMAP_TSL, + [VIRTIO_SND_CHMAP_TSR] = SNDRV_CHMAP_TSR, + [VIRTIO_SND_CHMAP_LLFE] = SNDRV_CHMAP_LLFE, + [VIRTIO_SND_CHMAP_RLFE] = SNDRV_CHMAP_RLFE, + [VIRTIO_SND_CHMAP_BC] = SNDRV_CHMAP_BC, + [VIRTIO_SND_CHMAP_BLC] = SNDRV_CHMAP_BLC, + [VIRTIO_SND_CHMAP_BRC] = SNDRV_CHMAP_BRC +}; + +/** + * virtsnd_chmap_parse_cfg() - Parse the channel map configuration. + * @snd: VirtIO sound device. + * + * This function is called during initial device initialization. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_chmap_parse_cfg(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + u32 i; + int rc; + + virtio_cread_le(vdev, struct virtio_snd_config, chmaps, &snd->nchmaps); + if (!snd->nchmaps) + return 0; + + snd->chmaps = devm_kcalloc(&vdev->dev, snd->nchmaps, + sizeof(*snd->chmaps), GFP_KERNEL); + if (!snd->chmaps) + return -ENOMEM; + + rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_CHMAP_INFO, 0, + snd->nchmaps, sizeof(*snd->chmaps), + snd->chmaps); + if (rc) + return rc; + + /* Count the number of channel maps per each PCM device/stream. */ + for (i = 0; i < snd->nchmaps; ++i) { + struct virtio_snd_chmap_info *info = &snd->chmaps[i]; + u32 nid = le32_to_cpu(info->hdr.hda_fn_nid); + struct virtio_pcm *vpcm; + struct virtio_pcm_stream *vs; + + vpcm = virtsnd_pcm_find_or_create(snd, nid); + if (IS_ERR(vpcm)) + return PTR_ERR(vpcm); + + switch (info->direction) { + case VIRTIO_SND_D_OUTPUT: + vs = &vpcm->streams[SNDRV_PCM_STREAM_PLAYBACK]; + break; + case VIRTIO_SND_D_INPUT: + vs = &vpcm->streams[SNDRV_PCM_STREAM_CAPTURE]; + break; + default: + dev_err(&vdev->dev, + "chmap #%u: unknown direction (%u)\n", i, + info->direction); + return -EINVAL; + } + + vs->nchmaps++; + } + + return 0; +} + +/** + * virtsnd_chmap_add_ctls() - Create an ALSA control for channel maps. + * @pcm: ALSA PCM device. + * @direction: PCM stream direction (SNDRV_PCM_STREAM_XXX). + * @vs: VirtIO PCM stream. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_chmap_add_ctls(struct snd_pcm *pcm, int direction, + struct virtio_pcm_stream *vs) +{ + u32 i; + int max_channels = 0; + + for (i = 0; i < vs->nchmaps; i++) + if (max_channels < vs->chmaps[i].channels) + max_channels = vs->chmaps[i].channels; + + return snd_pcm_add_chmap_ctls(pcm, direction, vs->chmaps, max_channels, + 0, NULL); +} + +/** + * virtsnd_chmap_build_devs() - Build ALSA controls for channel maps. + * @snd: VirtIO sound device. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_chmap_build_devs(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_pcm *vpcm; + struct virtio_pcm_stream *vs; + u32 i; + int rc; + + /* Allocate channel map elements per each PCM device/stream. */ + list_for_each_entry(vpcm, &snd->pcm_list, list) { + for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) { + vs = &vpcm->streams[i]; + + if (!vs->nchmaps) + continue; + + vs->chmaps = devm_kcalloc(&vdev->dev, vs->nchmaps + 1, + sizeof(*vs->chmaps), + GFP_KERNEL); + if (!vs->chmaps) + return -ENOMEM; + + vs->nchmaps = 0; + } + } + + /* Initialize channel maps per each PCM device/stream. */ + for (i = 0; i < snd->nchmaps; ++i) { + struct virtio_snd_chmap_info *info = &snd->chmaps[i]; + unsigned int channels = info->channels; + unsigned int ch; + struct snd_pcm_chmap_elem *chmap; + + vpcm = virtsnd_pcm_find(snd, le32_to_cpu(info->hdr.hda_fn_nid)); + if (IS_ERR(vpcm)) + return PTR_ERR(vpcm); + + if (info->direction == VIRTIO_SND_D_OUTPUT) + vs = &vpcm->streams[SNDRV_PCM_STREAM_PLAYBACK]; + else + vs = &vpcm->streams[SNDRV_PCM_STREAM_CAPTURE]; + + chmap = &vs->chmaps[vs->nchmaps++]; + + if (channels > ARRAY_SIZE(chmap->map)) + channels = ARRAY_SIZE(chmap->map); + + chmap->channels = channels; + + for (ch = 0; ch < channels; ++ch) { + u8 position = info->positions[ch]; + + if (position >= ARRAY_SIZE(g_v2a_position_map)) + return -EINVAL; + + chmap->map[ch] = g_v2a_position_map[position]; + } + } + + /* Create an ALSA control per each PCM device/stream. */ + list_for_each_entry(vpcm, &snd->pcm_list, list) { + if (!vpcm->pcm) + continue; + + for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) { + vs = &vpcm->streams[i]; + + if (!vs->nchmaps) + continue; + + rc = virtsnd_chmap_add_ctls(vpcm->pcm, i, vs); + if (rc) + return rc; + } + } + + return 0; +} diff --git a/sound/virtio/virtio_ctl_msg.c b/sound/virtio/virtio_ctl_msg.c new file mode 100644 index 0000000000..18dc5aca2e --- /dev/null +++ b/sound/virtio/virtio_ctl_msg.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <linux/moduleparam.h> +#include <linux/virtio_config.h> + +#include "virtio_card.h" + +/** + * struct virtio_snd_msg - Control message. + * @sg_request: Scattergather list containing a device request (header). + * @sg_response: Scattergather list containing a device response (status). + * @list: Pending message list entry. + * @notify: Request completed notification. + * @ref_count: Reference count used to manage a message lifetime. + */ +struct virtio_snd_msg { + struct scatterlist sg_request; + struct scatterlist sg_response; + struct list_head list; + struct completion notify; + refcount_t ref_count; +}; + +/** + * virtsnd_ctl_msg_ref() - Increment reference counter for the message. + * @msg: Control message. + * + * Context: Any context. + */ +void virtsnd_ctl_msg_ref(struct virtio_snd_msg *msg) +{ + refcount_inc(&msg->ref_count); +} + +/** + * virtsnd_ctl_msg_unref() - Decrement reference counter for the message. + * @msg: Control message. + * + * The message will be freed when the ref_count value is 0. + * + * Context: Any context. + */ +void virtsnd_ctl_msg_unref(struct virtio_snd_msg *msg) +{ + if (refcount_dec_and_test(&msg->ref_count)) + kfree(msg); +} + +/** + * virtsnd_ctl_msg_request() - Get a pointer to the request header. + * @msg: Control message. + * + * Context: Any context. + */ +void *virtsnd_ctl_msg_request(struct virtio_snd_msg *msg) +{ + return sg_virt(&msg->sg_request); +} + +/** + * virtsnd_ctl_msg_response() - Get a pointer to the response header. + * @msg: Control message. + * + * Context: Any context. + */ +void *virtsnd_ctl_msg_response(struct virtio_snd_msg *msg) +{ + return sg_virt(&msg->sg_response); +} + +/** + * virtsnd_ctl_msg_alloc() - Allocate and initialize a control message. + * @request_size: Size of request header. + * @response_size: Size of response header. + * @gfp: Kernel flags for memory allocation. + * + * The message will be automatically freed when the ref_count value is 0. + * + * Context: Any context. May sleep if @gfp flags permit. + * Return: Allocated message on success, NULL on failure. + */ +struct virtio_snd_msg *virtsnd_ctl_msg_alloc(size_t request_size, + size_t response_size, gfp_t gfp) +{ + struct virtio_snd_msg *msg; + + if (!request_size || !response_size) + return NULL; + + msg = kzalloc(sizeof(*msg) + request_size + response_size, gfp); + if (!msg) + return NULL; + + sg_init_one(&msg->sg_request, (u8 *)msg + sizeof(*msg), request_size); + sg_init_one(&msg->sg_response, (u8 *)msg + sizeof(*msg) + request_size, + response_size); + + INIT_LIST_HEAD(&msg->list); + init_completion(&msg->notify); + /* This reference is dropped in virtsnd_ctl_msg_complete(). */ + refcount_set(&msg->ref_count, 1); + + return msg; +} + +/** + * virtsnd_ctl_msg_send() - Send a control message. + * @snd: VirtIO sound device. + * @msg: Control message. + * @out_sgs: Additional sg-list to attach to the request header (may be NULL). + * @in_sgs: Additional sg-list to attach to the response header (may be NULL). + * @nowait: Flag indicating whether to wait for completion. + * + * Context: Any context. Takes and releases the control queue spinlock. + * May sleep if @nowait is false. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg, + struct scatterlist *out_sgs, + struct scatterlist *in_sgs, bool nowait) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_snd_queue *queue = virtsnd_control_queue(snd); + unsigned int js = msecs_to_jiffies(virtsnd_msg_timeout_ms); + struct virtio_snd_hdr *request = virtsnd_ctl_msg_request(msg); + struct virtio_snd_hdr *response = virtsnd_ctl_msg_response(msg); + unsigned int nouts = 0; + unsigned int nins = 0; + struct scatterlist *psgs[4]; + bool notify = false; + unsigned long flags; + int rc; + + virtsnd_ctl_msg_ref(msg); + + /* Set the default status in case the message was canceled. */ + response->code = cpu_to_le32(VIRTIO_SND_S_IO_ERR); + + psgs[nouts++] = &msg->sg_request; + if (out_sgs) + psgs[nouts++] = out_sgs; + + psgs[nouts + nins++] = &msg->sg_response; + if (in_sgs) + psgs[nouts + nins++] = in_sgs; + + spin_lock_irqsave(&queue->lock, flags); + rc = virtqueue_add_sgs(queue->vqueue, psgs, nouts, nins, msg, + GFP_ATOMIC); + if (!rc) { + notify = virtqueue_kick_prepare(queue->vqueue); + + list_add_tail(&msg->list, &snd->ctl_msgs); + } + spin_unlock_irqrestore(&queue->lock, flags); + + if (rc) { + dev_err(&vdev->dev, "failed to send control message (0x%08x)\n", + le32_to_cpu(request->code)); + + /* + * Since in this case virtsnd_ctl_msg_complete() will not be + * called, it is necessary to decrement the reference count. + */ + virtsnd_ctl_msg_unref(msg); + + goto on_exit; + } + + if (notify) + virtqueue_notify(queue->vqueue); + + if (nowait) + goto on_exit; + + rc = wait_for_completion_interruptible_timeout(&msg->notify, js); + if (rc <= 0) { + if (!rc) { + dev_err(&vdev->dev, + "control message (0x%08x) timeout\n", + le32_to_cpu(request->code)); + rc = -ETIMEDOUT; + } + + goto on_exit; + } + + switch (le32_to_cpu(response->code)) { + case VIRTIO_SND_S_OK: + rc = 0; + break; + case VIRTIO_SND_S_NOT_SUPP: + rc = -EOPNOTSUPP; + break; + case VIRTIO_SND_S_IO_ERR: + rc = -EIO; + break; + default: + rc = -EINVAL; + break; + } + +on_exit: + virtsnd_ctl_msg_unref(msg); + + return rc; +} + +/** + * virtsnd_ctl_msg_complete() - Complete a control message. + * @msg: Control message. + * + * Context: Any context. Expects the control queue spinlock to be held by + * caller. + */ +void virtsnd_ctl_msg_complete(struct virtio_snd_msg *msg) +{ + list_del(&msg->list); + complete(&msg->notify); + + virtsnd_ctl_msg_unref(msg); +} + +/** + * virtsnd_ctl_msg_cancel_all() - Cancel all pending control messages. + * @snd: VirtIO sound device. + * + * Context: Any context. + */ +void virtsnd_ctl_msg_cancel_all(struct virtio_snd *snd) +{ + struct virtio_snd_queue *queue = virtsnd_control_queue(snd); + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + while (!list_empty(&snd->ctl_msgs)) { + struct virtio_snd_msg *msg = + list_first_entry(&snd->ctl_msgs, struct virtio_snd_msg, + list); + + virtsnd_ctl_msg_complete(msg); + } + spin_unlock_irqrestore(&queue->lock, flags); +} + +/** + * virtsnd_ctl_query_info() - Query the item configuration from the device. + * @snd: VirtIO sound device. + * @command: Control request code (VIRTIO_SND_R_XXX_INFO). + * @start_id: Item start identifier. + * @count: Item count to query. + * @size: Item information size in bytes. + * @info: Buffer for storing item information. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_ctl_query_info(struct virtio_snd *snd, int command, int start_id, + int count, size_t size, void *info) +{ + struct virtio_snd_msg *msg; + struct virtio_snd_query_info *query; + struct scatterlist sg; + + msg = virtsnd_ctl_msg_alloc(sizeof(*query), + sizeof(struct virtio_snd_hdr), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + query = virtsnd_ctl_msg_request(msg); + query->hdr.code = cpu_to_le32(command); + query->start_id = cpu_to_le32(start_id); + query->count = cpu_to_le32(count); + query->size = cpu_to_le32(size); + + sg_init_one(&sg, info, count * size); + + return virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false); +} + +/** + * virtsnd_ctl_notify_cb() - Process all completed control messages. + * @vqueue: Underlying control virtqueue. + * + * This callback function is called upon a vring interrupt request from the + * device. + * + * Context: Interrupt context. Takes and releases the control queue spinlock. + */ +void virtsnd_ctl_notify_cb(struct virtqueue *vqueue) +{ + struct virtio_snd *snd = vqueue->vdev->priv; + struct virtio_snd_queue *queue = virtsnd_control_queue(snd); + struct virtio_snd_msg *msg; + u32 length; + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + do { + virtqueue_disable_cb(vqueue); + while ((msg = virtqueue_get_buf(vqueue, &length))) + virtsnd_ctl_msg_complete(msg); + if (unlikely(virtqueue_is_broken(vqueue))) + break; + } while (!virtqueue_enable_cb(vqueue)); + spin_unlock_irqrestore(&queue->lock, flags); +} diff --git a/sound/virtio/virtio_ctl_msg.h b/sound/virtio/virtio_ctl_msg.h new file mode 100644 index 0000000000..7f4db044f2 --- /dev/null +++ b/sound/virtio/virtio_ctl_msg.h @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#ifndef VIRTIO_SND_MSG_H +#define VIRTIO_SND_MSG_H + +#include <linux/atomic.h> +#include <linux/virtio.h> + +struct virtio_snd; +struct virtio_snd_msg; + +void virtsnd_ctl_msg_ref(struct virtio_snd_msg *msg); + +void virtsnd_ctl_msg_unref(struct virtio_snd_msg *msg); + +void *virtsnd_ctl_msg_request(struct virtio_snd_msg *msg); + +void *virtsnd_ctl_msg_response(struct virtio_snd_msg *msg); + +struct virtio_snd_msg *virtsnd_ctl_msg_alloc(size_t request_size, + size_t response_size, gfp_t gfp); + +int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg, + struct scatterlist *out_sgs, + struct scatterlist *in_sgs, bool nowait); + +/** + * virtsnd_ctl_msg_send_sync() - Simplified sending of synchronous message. + * @snd: VirtIO sound device. + * @msg: Control message. + * + * After returning from this function, the message will be deleted. If message + * content is still needed, the caller must additionally to + * virtsnd_ctl_msg_ref/unref() it. + * + * The msg_timeout_ms module parameter defines the message completion timeout. + * If the message is not completed within this time, the function will return an + * error. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + * + * The return value is a message status code (VIRTIO_SND_S_XXX) converted to an + * appropriate -errno value. + */ +static inline int virtsnd_ctl_msg_send_sync(struct virtio_snd *snd, + struct virtio_snd_msg *msg) +{ + return virtsnd_ctl_msg_send(snd, msg, NULL, NULL, false); +} + +/** + * virtsnd_ctl_msg_send_async() - Simplified sending of asynchronous message. + * @snd: VirtIO sound device. + * @msg: Control message. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +static inline int virtsnd_ctl_msg_send_async(struct virtio_snd *snd, + struct virtio_snd_msg *msg) +{ + return virtsnd_ctl_msg_send(snd, msg, NULL, NULL, true); +} + +void virtsnd_ctl_msg_cancel_all(struct virtio_snd *snd); + +void virtsnd_ctl_msg_complete(struct virtio_snd_msg *msg); + +int virtsnd_ctl_query_info(struct virtio_snd *snd, int command, int start_id, + int count, size_t size, void *info); + +void virtsnd_ctl_notify_cb(struct virtqueue *vqueue); + +#endif /* VIRTIO_SND_MSG_H */ diff --git a/sound/virtio/virtio_jack.c b/sound/virtio/virtio_jack.c new file mode 100644 index 0000000000..c69f1dcdcc --- /dev/null +++ b/sound/virtio/virtio_jack.c @@ -0,0 +1,233 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <linux/virtio_config.h> +#include <sound/jack.h> +#include <sound/hda_verbs.h> + +#include "virtio_card.h" + +/** + * DOC: Implementation Status + * + * At the moment jacks have a simple implementation and can only be used to + * receive notifications about a plugged in/out device. + * + * VIRTIO_SND_R_JACK_REMAP + * is not supported + */ + +/** + * struct virtio_jack - VirtIO jack. + * @jack: Kernel jack control. + * @nid: Functional group node identifier. + * @features: Jack virtio feature bit map (1 << VIRTIO_SND_JACK_F_XXX). + * @defconf: Pin default configuration value. + * @caps: Pin capabilities value. + * @connected: Current jack connection status. + * @type: Kernel jack type (SND_JACK_XXX). + */ +struct virtio_jack { + struct snd_jack *jack; + u32 nid; + u32 features; + u32 defconf; + u32 caps; + bool connected; + int type; +}; + +/** + * virtsnd_jack_get_label() - Get the name string for the jack. + * @vjack: VirtIO jack. + * + * Returns the jack name based on the default pin configuration value (see HDA + * specification). + * + * Context: Any context. + * Return: Name string. + */ +static const char *virtsnd_jack_get_label(struct virtio_jack *vjack) +{ + unsigned int defconf = vjack->defconf; + unsigned int device = + (defconf & AC_DEFCFG_DEVICE) >> AC_DEFCFG_DEVICE_SHIFT; + unsigned int location = + (defconf & AC_DEFCFG_LOCATION) >> AC_DEFCFG_LOCATION_SHIFT; + + switch (device) { + case AC_JACK_LINE_OUT: + return "Line Out"; + case AC_JACK_SPEAKER: + return "Speaker"; + case AC_JACK_HP_OUT: + return "Headphone"; + case AC_JACK_CD: + return "CD"; + case AC_JACK_SPDIF_OUT: + case AC_JACK_DIG_OTHER_OUT: + if (location == AC_JACK_LOC_HDMI) + return "HDMI Out"; + else + return "SPDIF Out"; + case AC_JACK_LINE_IN: + return "Line"; + case AC_JACK_AUX: + return "Aux"; + case AC_JACK_MIC_IN: + return "Mic"; + case AC_JACK_SPDIF_IN: + return "SPDIF In"; + case AC_JACK_DIG_OTHER_IN: + return "Digital In"; + default: + return "Misc"; + } +} + +/** + * virtsnd_jack_get_type() - Get the type for the jack. + * @vjack: VirtIO jack. + * + * Returns the jack type based on the default pin configuration value (see HDA + * specification). + * + * Context: Any context. + * Return: SND_JACK_XXX value. + */ +static int virtsnd_jack_get_type(struct virtio_jack *vjack) +{ + unsigned int defconf = vjack->defconf; + unsigned int device = + (defconf & AC_DEFCFG_DEVICE) >> AC_DEFCFG_DEVICE_SHIFT; + + switch (device) { + case AC_JACK_LINE_OUT: + case AC_JACK_SPEAKER: + return SND_JACK_LINEOUT; + case AC_JACK_HP_OUT: + return SND_JACK_HEADPHONE; + case AC_JACK_SPDIF_OUT: + case AC_JACK_DIG_OTHER_OUT: + return SND_JACK_AVOUT; + case AC_JACK_MIC_IN: + return SND_JACK_MICROPHONE; + default: + return SND_JACK_LINEIN; + } +} + +/** + * virtsnd_jack_parse_cfg() - Parse the jack configuration. + * @snd: VirtIO sound device. + * + * This function is called during initial device initialization. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_jack_parse_cfg(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_snd_jack_info *info; + u32 i; + int rc; + + virtio_cread_le(vdev, struct virtio_snd_config, jacks, &snd->njacks); + if (!snd->njacks) + return 0; + + snd->jacks = devm_kcalloc(&vdev->dev, snd->njacks, sizeof(*snd->jacks), + GFP_KERNEL); + if (!snd->jacks) + return -ENOMEM; + + info = kcalloc(snd->njacks, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_JACK_INFO, 0, snd->njacks, + sizeof(*info), info); + if (rc) + goto on_exit; + + for (i = 0; i < snd->njacks; ++i) { + struct virtio_jack *vjack = &snd->jacks[i]; + + vjack->nid = le32_to_cpu(info[i].hdr.hda_fn_nid); + vjack->features = le32_to_cpu(info[i].features); + vjack->defconf = le32_to_cpu(info[i].hda_reg_defconf); + vjack->caps = le32_to_cpu(info[i].hda_reg_caps); + vjack->connected = info[i].connected; + } + +on_exit: + kfree(info); + + return rc; +} + +/** + * virtsnd_jack_build_devs() - Build ALSA controls for jacks. + * @snd: VirtIO sound device. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_jack_build_devs(struct virtio_snd *snd) +{ + u32 i; + int rc; + + for (i = 0; i < snd->njacks; ++i) { + struct virtio_jack *vjack = &snd->jacks[i]; + + vjack->type = virtsnd_jack_get_type(vjack); + + rc = snd_jack_new(snd->card, virtsnd_jack_get_label(vjack), + vjack->type, &vjack->jack, true, true); + if (rc) + return rc; + + if (vjack->jack) + vjack->jack->private_data = vjack; + + snd_jack_report(vjack->jack, + vjack->connected ? vjack->type : 0); + } + + return 0; +} + +/** + * virtsnd_jack_event() - Handle the jack event notification. + * @snd: VirtIO sound device. + * @event: VirtIO sound event. + * + * Context: Interrupt context. + */ +void virtsnd_jack_event(struct virtio_snd *snd, struct virtio_snd_event *event) +{ + u32 jack_id = le32_to_cpu(event->data); + struct virtio_jack *vjack; + + if (jack_id >= snd->njacks) + return; + + vjack = &snd->jacks[jack_id]; + + switch (le32_to_cpu(event->hdr.code)) { + case VIRTIO_SND_EVT_JACK_CONNECTED: + vjack->connected = true; + break; + case VIRTIO_SND_EVT_JACK_DISCONNECTED: + vjack->connected = false; + break; + default: + return; + } + + snd_jack_report(vjack->jack, vjack->connected ? vjack->type : 0); +} diff --git a/sound/virtio/virtio_pcm.c b/sound/virtio/virtio_pcm.c new file mode 100644 index 0000000000..c10d91fff2 --- /dev/null +++ b/sound/virtio/virtio_pcm.c @@ -0,0 +1,513 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <linux/moduleparam.h> +#include <linux/virtio_config.h> + +#include "virtio_card.h" + +static u32 pcm_buffer_ms = 160; +module_param(pcm_buffer_ms, uint, 0644); +MODULE_PARM_DESC(pcm_buffer_ms, "PCM substream buffer time in milliseconds"); + +static u32 pcm_periods_min = 2; +module_param(pcm_periods_min, uint, 0644); +MODULE_PARM_DESC(pcm_periods_min, "Minimum number of PCM periods"); + +static u32 pcm_periods_max = 16; +module_param(pcm_periods_max, uint, 0644); +MODULE_PARM_DESC(pcm_periods_max, "Maximum number of PCM periods"); + +static u32 pcm_period_ms_min = 10; +module_param(pcm_period_ms_min, uint, 0644); +MODULE_PARM_DESC(pcm_period_ms_min, "Minimum PCM period time in milliseconds"); + +static u32 pcm_period_ms_max = 80; +module_param(pcm_period_ms_max, uint, 0644); +MODULE_PARM_DESC(pcm_period_ms_max, "Maximum PCM period time in milliseconds"); + +/* Map for converting VirtIO format to ALSA format. */ +static const snd_pcm_format_t g_v2a_format_map[] = { + [VIRTIO_SND_PCM_FMT_IMA_ADPCM] = SNDRV_PCM_FORMAT_IMA_ADPCM, + [VIRTIO_SND_PCM_FMT_MU_LAW] = SNDRV_PCM_FORMAT_MU_LAW, + [VIRTIO_SND_PCM_FMT_A_LAW] = SNDRV_PCM_FORMAT_A_LAW, + [VIRTIO_SND_PCM_FMT_S8] = SNDRV_PCM_FORMAT_S8, + [VIRTIO_SND_PCM_FMT_U8] = SNDRV_PCM_FORMAT_U8, + [VIRTIO_SND_PCM_FMT_S16] = SNDRV_PCM_FORMAT_S16_LE, + [VIRTIO_SND_PCM_FMT_U16] = SNDRV_PCM_FORMAT_U16_LE, + [VIRTIO_SND_PCM_FMT_S18_3] = SNDRV_PCM_FORMAT_S18_3LE, + [VIRTIO_SND_PCM_FMT_U18_3] = SNDRV_PCM_FORMAT_U18_3LE, + [VIRTIO_SND_PCM_FMT_S20_3] = SNDRV_PCM_FORMAT_S20_3LE, + [VIRTIO_SND_PCM_FMT_U20_3] = SNDRV_PCM_FORMAT_U20_3LE, + [VIRTIO_SND_PCM_FMT_S24_3] = SNDRV_PCM_FORMAT_S24_3LE, + [VIRTIO_SND_PCM_FMT_U24_3] = SNDRV_PCM_FORMAT_U24_3LE, + [VIRTIO_SND_PCM_FMT_S20] = SNDRV_PCM_FORMAT_S20_LE, + [VIRTIO_SND_PCM_FMT_U20] = SNDRV_PCM_FORMAT_U20_LE, + [VIRTIO_SND_PCM_FMT_S24] = SNDRV_PCM_FORMAT_S24_LE, + [VIRTIO_SND_PCM_FMT_U24] = SNDRV_PCM_FORMAT_U24_LE, + [VIRTIO_SND_PCM_FMT_S32] = SNDRV_PCM_FORMAT_S32_LE, + [VIRTIO_SND_PCM_FMT_U32] = SNDRV_PCM_FORMAT_U32_LE, + [VIRTIO_SND_PCM_FMT_FLOAT] = SNDRV_PCM_FORMAT_FLOAT_LE, + [VIRTIO_SND_PCM_FMT_FLOAT64] = SNDRV_PCM_FORMAT_FLOAT64_LE, + [VIRTIO_SND_PCM_FMT_DSD_U8] = SNDRV_PCM_FORMAT_DSD_U8, + [VIRTIO_SND_PCM_FMT_DSD_U16] = SNDRV_PCM_FORMAT_DSD_U16_LE, + [VIRTIO_SND_PCM_FMT_DSD_U32] = SNDRV_PCM_FORMAT_DSD_U32_LE, + [VIRTIO_SND_PCM_FMT_IEC958_SUBFRAME] = + SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE +}; + +/* Map for converting VirtIO frame rate to ALSA frame rate. */ +struct virtsnd_v2a_rate { + unsigned int alsa_bit; + unsigned int rate; +}; + +static const struct virtsnd_v2a_rate g_v2a_rate_map[] = { + [VIRTIO_SND_PCM_RATE_5512] = { SNDRV_PCM_RATE_5512, 5512 }, + [VIRTIO_SND_PCM_RATE_8000] = { SNDRV_PCM_RATE_8000, 8000 }, + [VIRTIO_SND_PCM_RATE_11025] = { SNDRV_PCM_RATE_11025, 11025 }, + [VIRTIO_SND_PCM_RATE_16000] = { SNDRV_PCM_RATE_16000, 16000 }, + [VIRTIO_SND_PCM_RATE_22050] = { SNDRV_PCM_RATE_22050, 22050 }, + [VIRTIO_SND_PCM_RATE_32000] = { SNDRV_PCM_RATE_32000, 32000 }, + [VIRTIO_SND_PCM_RATE_44100] = { SNDRV_PCM_RATE_44100, 44100 }, + [VIRTIO_SND_PCM_RATE_48000] = { SNDRV_PCM_RATE_48000, 48000 }, + [VIRTIO_SND_PCM_RATE_64000] = { SNDRV_PCM_RATE_64000, 64000 }, + [VIRTIO_SND_PCM_RATE_88200] = { SNDRV_PCM_RATE_88200, 88200 }, + [VIRTIO_SND_PCM_RATE_96000] = { SNDRV_PCM_RATE_96000, 96000 }, + [VIRTIO_SND_PCM_RATE_176400] = { SNDRV_PCM_RATE_176400, 176400 }, + [VIRTIO_SND_PCM_RATE_192000] = { SNDRV_PCM_RATE_192000, 192000 } +}; + +/** + * virtsnd_pcm_build_hw() - Parse substream config and build HW descriptor. + * @vss: VirtIO substream. + * @info: VirtIO substream information entry. + * + * Context: Any context. + * Return: 0 on success, -EINVAL if configuration is invalid. + */ +static int virtsnd_pcm_build_hw(struct virtio_pcm_substream *vss, + struct virtio_snd_pcm_info *info) +{ + struct virtio_device *vdev = vss->snd->vdev; + unsigned int i; + u64 values; + size_t sample_max = 0; + size_t sample_min = 0; + + vss->features = le32_to_cpu(info->features); + + /* + * TODO: set SNDRV_PCM_INFO_{BATCH,BLOCK_TRANSFER} if device supports + * only message-based transport. + */ + vss->hw.info = + SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_BATCH | + SNDRV_PCM_INFO_BLOCK_TRANSFER | + SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_PAUSE; + + if (!info->channels_min || info->channels_min > info->channels_max) { + dev_err(&vdev->dev, + "SID %u: invalid channel range [%u %u]\n", + vss->sid, info->channels_min, info->channels_max); + return -EINVAL; + } + + vss->hw.channels_min = info->channels_min; + vss->hw.channels_max = info->channels_max; + + values = le64_to_cpu(info->formats); + + vss->hw.formats = 0; + + for (i = 0; i < ARRAY_SIZE(g_v2a_format_map); ++i) + if (values & (1ULL << i)) { + snd_pcm_format_t alsa_fmt = g_v2a_format_map[i]; + int bytes = snd_pcm_format_physical_width(alsa_fmt) / 8; + + if (!sample_min || sample_min > bytes) + sample_min = bytes; + + if (sample_max < bytes) + sample_max = bytes; + + vss->hw.formats |= pcm_format_to_bits(alsa_fmt); + } + + if (!vss->hw.formats) { + dev_err(&vdev->dev, + "SID %u: no supported PCM sample formats found\n", + vss->sid); + return -EINVAL; + } + + values = le64_to_cpu(info->rates); + + vss->hw.rates = 0; + + for (i = 0; i < ARRAY_SIZE(g_v2a_rate_map); ++i) + if (values & (1ULL << i)) { + if (!vss->hw.rate_min || + vss->hw.rate_min > g_v2a_rate_map[i].rate) + vss->hw.rate_min = g_v2a_rate_map[i].rate; + + if (vss->hw.rate_max < g_v2a_rate_map[i].rate) + vss->hw.rate_max = g_v2a_rate_map[i].rate; + + vss->hw.rates |= g_v2a_rate_map[i].alsa_bit; + } + + if (!vss->hw.rates) { + dev_err(&vdev->dev, + "SID %u: no supported PCM frame rates found\n", + vss->sid); + return -EINVAL; + } + + vss->hw.periods_min = pcm_periods_min; + vss->hw.periods_max = pcm_periods_max; + + /* + * We must ensure that there is enough space in the buffer to store + * pcm_buffer_ms ms for the combination (Cmax, Smax, Rmax), where: + * Cmax = maximum supported number of channels, + * Smax = maximum supported sample size in bytes, + * Rmax = maximum supported frame rate. + */ + vss->hw.buffer_bytes_max = + PAGE_ALIGN(sample_max * vss->hw.channels_max * pcm_buffer_ms * + (vss->hw.rate_max / MSEC_PER_SEC)); + + /* + * We must ensure that the minimum period size is enough to store + * pcm_period_ms_min ms for the combination (Cmin, Smin, Rmin), where: + * Cmin = minimum supported number of channels, + * Smin = minimum supported sample size in bytes, + * Rmin = minimum supported frame rate. + */ + vss->hw.period_bytes_min = + sample_min * vss->hw.channels_min * pcm_period_ms_min * + (vss->hw.rate_min / MSEC_PER_SEC); + + /* + * We must ensure that the maximum period size is enough to store + * pcm_period_ms_max ms for the combination (Cmax, Smax, Rmax). + */ + vss->hw.period_bytes_max = + sample_max * vss->hw.channels_max * pcm_period_ms_max * + (vss->hw.rate_max / MSEC_PER_SEC); + + return 0; +} + +/** + * virtsnd_pcm_find() - Find the PCM device for the specified node ID. + * @snd: VirtIO sound device. + * @nid: Function node ID. + * + * Context: Any context. + * Return: a pointer to the PCM device or ERR_PTR(-ENOENT). + */ +struct virtio_pcm *virtsnd_pcm_find(struct virtio_snd *snd, u32 nid) +{ + struct virtio_pcm *vpcm; + + list_for_each_entry(vpcm, &snd->pcm_list, list) + if (vpcm->nid == nid) + return vpcm; + + return ERR_PTR(-ENOENT); +} + +/** + * virtsnd_pcm_find_or_create() - Find or create the PCM device for the + * specified node ID. + * @snd: VirtIO sound device. + * @nid: Function node ID. + * + * Context: Any context that permits to sleep. + * Return: a pointer to the PCM device or ERR_PTR(-errno). + */ +struct virtio_pcm *virtsnd_pcm_find_or_create(struct virtio_snd *snd, u32 nid) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_pcm *vpcm; + + vpcm = virtsnd_pcm_find(snd, nid); + if (!IS_ERR(vpcm)) + return vpcm; + + vpcm = devm_kzalloc(&vdev->dev, sizeof(*vpcm), GFP_KERNEL); + if (!vpcm) + return ERR_PTR(-ENOMEM); + + vpcm->nid = nid; + list_add_tail(&vpcm->list, &snd->pcm_list); + + return vpcm; +} + +/** + * virtsnd_pcm_validate() - Validate if the device can be started. + * @vdev: VirtIO parent device. + * + * Context: Any context. + * Return: 0 on success, -EINVAL on failure. + */ +int virtsnd_pcm_validate(struct virtio_device *vdev) +{ + if (pcm_periods_min < 2 || pcm_periods_min > pcm_periods_max) { + dev_err(&vdev->dev, + "invalid range [%u %u] of the number of PCM periods\n", + pcm_periods_min, pcm_periods_max); + return -EINVAL; + } + + if (!pcm_period_ms_min || pcm_period_ms_min > pcm_period_ms_max) { + dev_err(&vdev->dev, + "invalid range [%u %u] of the size of the PCM period\n", + pcm_period_ms_min, pcm_period_ms_max); + return -EINVAL; + } + + if (pcm_buffer_ms < pcm_periods_min * pcm_period_ms_min) { + dev_err(&vdev->dev, + "pcm_buffer_ms(=%u) value cannot be < %u ms\n", + pcm_buffer_ms, pcm_periods_min * pcm_period_ms_min); + return -EINVAL; + } + + if (pcm_period_ms_max > pcm_buffer_ms / 2) { + dev_err(&vdev->dev, + "pcm_period_ms_max(=%u) value cannot be > %u ms\n", + pcm_period_ms_max, pcm_buffer_ms / 2); + return -EINVAL; + } + + return 0; +} + +/** + * virtsnd_pcm_period_elapsed() - Kernel work function to handle the elapsed + * period state. + * @work: Elapsed period work. + * + * The main purpose of this function is to call snd_pcm_period_elapsed() in + * a process context, not in an interrupt context. This is necessary because PCM + * devices operate in non-atomic mode. + * + * Context: Process context. + */ +static void virtsnd_pcm_period_elapsed(struct work_struct *work) +{ + struct virtio_pcm_substream *vss = + container_of(work, struct virtio_pcm_substream, elapsed_period); + + snd_pcm_period_elapsed(vss->substream); +} + +/** + * virtsnd_pcm_parse_cfg() - Parse the stream configuration. + * @snd: VirtIO sound device. + * + * This function is called during initial device initialization. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_pcm_parse_cfg(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_snd_pcm_info *info; + u32 i; + int rc; + + virtio_cread_le(vdev, struct virtio_snd_config, streams, + &snd->nsubstreams); + if (!snd->nsubstreams) + return 0; + + snd->substreams = devm_kcalloc(&vdev->dev, snd->nsubstreams, + sizeof(*snd->substreams), GFP_KERNEL); + if (!snd->substreams) + return -ENOMEM; + + info = kcalloc(snd->nsubstreams, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_PCM_INFO, 0, + snd->nsubstreams, sizeof(*info), info); + if (rc) + goto on_exit; + + for (i = 0; i < snd->nsubstreams; ++i) { + struct virtio_pcm_substream *vss = &snd->substreams[i]; + struct virtio_pcm *vpcm; + + vss->snd = snd; + vss->sid = i; + INIT_WORK(&vss->elapsed_period, virtsnd_pcm_period_elapsed); + init_waitqueue_head(&vss->msg_empty); + spin_lock_init(&vss->lock); + + rc = virtsnd_pcm_build_hw(vss, &info[i]); + if (rc) + goto on_exit; + + vss->nid = le32_to_cpu(info[i].hdr.hda_fn_nid); + + vpcm = virtsnd_pcm_find_or_create(snd, vss->nid); + if (IS_ERR(vpcm)) { + rc = PTR_ERR(vpcm); + goto on_exit; + } + + switch (info[i].direction) { + case VIRTIO_SND_D_OUTPUT: + vss->direction = SNDRV_PCM_STREAM_PLAYBACK; + break; + case VIRTIO_SND_D_INPUT: + vss->direction = SNDRV_PCM_STREAM_CAPTURE; + break; + default: + dev_err(&vdev->dev, "SID %u: unknown direction (%u)\n", + vss->sid, info[i].direction); + rc = -EINVAL; + goto on_exit; + } + + vpcm->streams[vss->direction].nsubstreams++; + } + +on_exit: + kfree(info); + + return rc; +} + +/** + * virtsnd_pcm_build_devs() - Build ALSA PCM devices. + * @snd: VirtIO sound device. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_pcm_build_devs(struct virtio_snd *snd) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_pcm *vpcm; + u32 i; + int rc; + + list_for_each_entry(vpcm, &snd->pcm_list, list) { + unsigned int npbs = + vpcm->streams[SNDRV_PCM_STREAM_PLAYBACK].nsubstreams; + unsigned int ncps = + vpcm->streams[SNDRV_PCM_STREAM_CAPTURE].nsubstreams; + + if (!npbs && !ncps) + continue; + + rc = snd_pcm_new(snd->card, VIRTIO_SND_CARD_DRIVER, vpcm->nid, + npbs, ncps, &vpcm->pcm); + if (rc) { + dev_err(&vdev->dev, "snd_pcm_new[%u] failed: %d\n", + vpcm->nid, rc); + return rc; + } + + vpcm->pcm->info_flags = 0; + vpcm->pcm->dev_class = SNDRV_PCM_CLASS_GENERIC; + vpcm->pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX; + snprintf(vpcm->pcm->name, sizeof(vpcm->pcm->name), + VIRTIO_SND_PCM_NAME " %u", vpcm->pcm->device); + vpcm->pcm->private_data = vpcm; + vpcm->pcm->nonatomic = true; + + for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) { + struct virtio_pcm_stream *stream = &vpcm->streams[i]; + + if (!stream->nsubstreams) + continue; + + stream->substreams = + devm_kcalloc(&vdev->dev, stream->nsubstreams, + sizeof(*stream->substreams), + GFP_KERNEL); + if (!stream->substreams) + return -ENOMEM; + + stream->nsubstreams = 0; + } + } + + for (i = 0; i < snd->nsubstreams; ++i) { + struct virtio_pcm_stream *vs; + struct virtio_pcm_substream *vss = &snd->substreams[i]; + + vpcm = virtsnd_pcm_find(snd, vss->nid); + if (IS_ERR(vpcm)) + return PTR_ERR(vpcm); + + vs = &vpcm->streams[vss->direction]; + vs->substreams[vs->nsubstreams++] = vss; + } + + list_for_each_entry(vpcm, &snd->pcm_list, list) { + for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) { + struct virtio_pcm_stream *vs = &vpcm->streams[i]; + struct snd_pcm_str *ks = &vpcm->pcm->streams[i]; + struct snd_pcm_substream *kss; + + if (!vs->nsubstreams) + continue; + + for (kss = ks->substream; kss; kss = kss->next) + vs->substreams[kss->number]->substream = kss; + + snd_pcm_set_ops(vpcm->pcm, i, &virtsnd_pcm_ops); + } + + snd_pcm_set_managed_buffer_all(vpcm->pcm, + SNDRV_DMA_TYPE_VMALLOC, NULL, + 0, 0); + } + + return 0; +} + +/** + * virtsnd_pcm_event() - Handle the PCM device event notification. + * @snd: VirtIO sound device. + * @event: VirtIO sound event. + * + * Context: Interrupt context. + */ +void virtsnd_pcm_event(struct virtio_snd *snd, struct virtio_snd_event *event) +{ + struct virtio_pcm_substream *vss; + u32 sid = le32_to_cpu(event->data); + + if (sid >= snd->nsubstreams) + return; + + vss = &snd->substreams[sid]; + + switch (le32_to_cpu(event->hdr.code)) { + case VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED: + /* TODO: deal with shmem elapsed period */ + break; + case VIRTIO_SND_EVT_PCM_XRUN: + spin_lock(&vss->lock); + if (vss->xfer_enabled) + vss->xfer_xrun = true; + spin_unlock(&vss->lock); + break; + } +} diff --git a/sound/virtio/virtio_pcm.h b/sound/virtio/virtio_pcm.h new file mode 100644 index 0000000000..062eb8e8f2 --- /dev/null +++ b/sound/virtio/virtio_pcm.h @@ -0,0 +1,124 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#ifndef VIRTIO_SND_PCM_H +#define VIRTIO_SND_PCM_H + +#include <linux/atomic.h> +#include <linux/virtio_config.h> +#include <sound/pcm.h> + +struct virtio_pcm; +struct virtio_pcm_msg; + +/** + * struct virtio_pcm_substream - VirtIO PCM substream. + * @snd: VirtIO sound device. + * @nid: Function group node identifier. + * @sid: Stream identifier. + * @direction: Stream data flow direction (SNDRV_PCM_STREAM_XXX). + * @features: Stream VirtIO feature bit map (1 << VIRTIO_SND_PCM_F_XXX). + * @substream: Kernel ALSA substream. + * @hw: Kernel ALSA substream hardware descriptor. + * @elapsed_period: Kernel work to handle the elapsed period state. + * @lock: Spinlock that protects fields shared by interrupt handlers and + * substream operators. + * @buffer_bytes: Current buffer size in bytes. + * @hw_ptr: Substream hardware pointer value in bytes [0 ... buffer_bytes). + * @xfer_enabled: Data transfer state (0 - off, 1 - on). + * @xfer_xrun: Data underflow/overflow state (0 - no xrun, 1 - xrun). + * @stopped: True if the substream is stopped and must be released on the device + * side. + * @suspended: True if the substream is suspended and must be reconfigured on + * the device side at resume. + * @msgs: Allocated I/O messages. + * @nmsgs: Number of allocated I/O messages. + * @msg_last_enqueued: Index of the last I/O message added to the virtqueue. + * @msg_count: Number of pending I/O messages in the virtqueue. + * @msg_empty: Notify when msg_count is zero. + */ +struct virtio_pcm_substream { + struct virtio_snd *snd; + u32 nid; + u32 sid; + u32 direction; + u32 features; + struct snd_pcm_substream *substream; + struct snd_pcm_hardware hw; + struct work_struct elapsed_period; + spinlock_t lock; + size_t buffer_bytes; + size_t hw_ptr; + bool xfer_enabled; + bool xfer_xrun; + bool stopped; + bool suspended; + struct virtio_pcm_msg **msgs; + unsigned int nmsgs; + int msg_last_enqueued; + unsigned int msg_count; + wait_queue_head_t msg_empty; +}; + +/** + * struct virtio_pcm_stream - VirtIO PCM stream. + * @substreams: VirtIO substreams belonging to the stream. + * @nsubstreams: Number of substreams. + * @chmaps: Kernel channel maps belonging to the stream. + * @nchmaps: Number of channel maps. + */ +struct virtio_pcm_stream { + struct virtio_pcm_substream **substreams; + u32 nsubstreams; + struct snd_pcm_chmap_elem *chmaps; + u32 nchmaps; +}; + +/** + * struct virtio_pcm - VirtIO PCM device. + * @list: VirtIO PCM list entry. + * @nid: Function group node identifier. + * @pcm: Kernel PCM device. + * @streams: VirtIO PCM streams (playback and capture). + */ +struct virtio_pcm { + struct list_head list; + u32 nid; + struct snd_pcm *pcm; + struct virtio_pcm_stream streams[SNDRV_PCM_STREAM_LAST + 1]; +}; + +extern const struct snd_pcm_ops virtsnd_pcm_ops; + +int virtsnd_pcm_validate(struct virtio_device *vdev); + +int virtsnd_pcm_parse_cfg(struct virtio_snd *snd); + +int virtsnd_pcm_build_devs(struct virtio_snd *snd); + +void virtsnd_pcm_event(struct virtio_snd *snd, struct virtio_snd_event *event); + +void virtsnd_pcm_tx_notify_cb(struct virtqueue *vqueue); + +void virtsnd_pcm_rx_notify_cb(struct virtqueue *vqueue); + +struct virtio_pcm *virtsnd_pcm_find(struct virtio_snd *snd, u32 nid); + +struct virtio_pcm *virtsnd_pcm_find_or_create(struct virtio_snd *snd, u32 nid); + +struct virtio_snd_msg * +virtsnd_pcm_ctl_msg_alloc(struct virtio_pcm_substream *vss, + unsigned int command, gfp_t gfp); + +int virtsnd_pcm_msg_alloc(struct virtio_pcm_substream *vss, + unsigned int periods, unsigned int period_bytes); + +void virtsnd_pcm_msg_free(struct virtio_pcm_substream *vss); + +int virtsnd_pcm_msg_send(struct virtio_pcm_substream *vss); + +unsigned int virtsnd_pcm_msg_pending_num(struct virtio_pcm_substream *vss); + +#endif /* VIRTIO_SND_PCM_H */ diff --git a/sound/virtio/virtio_pcm_msg.c b/sound/virtio/virtio_pcm_msg.c new file mode 100644 index 0000000000..aca2dc1989 --- /dev/null +++ b/sound/virtio/virtio_pcm_msg.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <sound/pcm_params.h> + +#include "virtio_card.h" + +/** + * struct virtio_pcm_msg - VirtIO I/O message. + * @substream: VirtIO PCM substream. + * @xfer: Request header payload. + * @status: Response header payload. + * @length: Data length in bytes. + * @sgs: Payload scatter-gather table. + */ +struct virtio_pcm_msg { + struct virtio_pcm_substream *substream; + struct virtio_snd_pcm_xfer xfer; + struct virtio_snd_pcm_status status; + size_t length; + struct scatterlist sgs[]; +}; + +/** + * enum pcm_msg_sg_index - Index values for the virtio_pcm_msg->sgs field in + * an I/O message. + * @PCM_MSG_SG_XFER: Element containing a virtio_snd_pcm_xfer structure. + * @PCM_MSG_SG_STATUS: Element containing a virtio_snd_pcm_status structure. + * @PCM_MSG_SG_DATA: The first element containing a data buffer. + */ +enum pcm_msg_sg_index { + PCM_MSG_SG_XFER = 0, + PCM_MSG_SG_STATUS, + PCM_MSG_SG_DATA +}; + +/** + * virtsnd_pcm_sg_num() - Count the number of sg-elements required to represent + * vmalloc'ed buffer. + * @data: Pointer to vmalloc'ed buffer. + * @length: Buffer size. + * + * Context: Any context. + * Return: Number of physically contiguous parts in the @data. + */ +static int virtsnd_pcm_sg_num(u8 *data, unsigned int length) +{ + phys_addr_t sg_address; + unsigned int sg_length; + int num = 0; + + while (length) { + struct page *pg = vmalloc_to_page(data); + phys_addr_t pg_address = page_to_phys(pg); + size_t pg_length; + + pg_length = PAGE_SIZE - offset_in_page(data); + if (pg_length > length) + pg_length = length; + + if (!num || sg_address + sg_length != pg_address) { + sg_address = pg_address; + sg_length = pg_length; + num++; + } else { + sg_length += pg_length; + } + + data += pg_length; + length -= pg_length; + } + + return num; +} + +/** + * virtsnd_pcm_sg_from() - Build sg-list from vmalloc'ed buffer. + * @sgs: Preallocated sg-list to populate. + * @nsgs: The maximum number of elements in the @sgs. + * @data: Pointer to vmalloc'ed buffer. + * @length: Buffer size. + * + * Splits the buffer into physically contiguous parts and makes an sg-list of + * such parts. + * + * Context: Any context. + */ +static void virtsnd_pcm_sg_from(struct scatterlist *sgs, int nsgs, u8 *data, + unsigned int length) +{ + int idx = -1; + + while (length) { + struct page *pg = vmalloc_to_page(data); + size_t pg_length; + + pg_length = PAGE_SIZE - offset_in_page(data); + if (pg_length > length) + pg_length = length; + + if (idx == -1 || + sg_phys(&sgs[idx]) + sgs[idx].length != page_to_phys(pg)) { + if (idx + 1 == nsgs) + break; + sg_set_page(&sgs[++idx], pg, pg_length, + offset_in_page(data)); + } else { + sgs[idx].length += pg_length; + } + + data += pg_length; + length -= pg_length; + } + + sg_mark_end(&sgs[idx]); +} + +/** + * virtsnd_pcm_msg_alloc() - Allocate I/O messages. + * @vss: VirtIO PCM substream. + * @periods: Current number of periods. + * @period_bytes: Current period size in bytes. + * + * The function slices the buffer into @periods parts (each with the size of + * @period_bytes), and creates @periods corresponding I/O messages. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -ENOMEM on failure. + */ +int virtsnd_pcm_msg_alloc(struct virtio_pcm_substream *vss, + unsigned int periods, unsigned int period_bytes) +{ + struct snd_pcm_runtime *runtime = vss->substream->runtime; + unsigned int i; + + vss->msgs = kcalloc(periods, sizeof(*vss->msgs), GFP_KERNEL); + if (!vss->msgs) + return -ENOMEM; + + vss->nmsgs = periods; + + for (i = 0; i < periods; ++i) { + u8 *data = runtime->dma_area + period_bytes * i; + int sg_num = virtsnd_pcm_sg_num(data, period_bytes); + struct virtio_pcm_msg *msg; + + msg = kzalloc(struct_size(msg, sgs, sg_num + 2), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->substream = vss; + sg_init_one(&msg->sgs[PCM_MSG_SG_XFER], &msg->xfer, + sizeof(msg->xfer)); + sg_init_one(&msg->sgs[PCM_MSG_SG_STATUS], &msg->status, + sizeof(msg->status)); + msg->length = period_bytes; + virtsnd_pcm_sg_from(&msg->sgs[PCM_MSG_SG_DATA], sg_num, data, + period_bytes); + + vss->msgs[i] = msg; + } + + return 0; +} + +/** + * virtsnd_pcm_msg_free() - Free all allocated I/O messages. + * @vss: VirtIO PCM substream. + * + * Context: Any context. + */ +void virtsnd_pcm_msg_free(struct virtio_pcm_substream *vss) +{ + unsigned int i; + + for (i = 0; vss->msgs && i < vss->nmsgs; ++i) + kfree(vss->msgs[i]); + kfree(vss->msgs); + + vss->msgs = NULL; + vss->nmsgs = 0; +} + +/** + * virtsnd_pcm_msg_send() - Send asynchronous I/O messages. + * @vss: VirtIO PCM substream. + * + * All messages are organized in an ordered circular list. Each time the + * function is called, all currently non-enqueued messages are added to the + * virtqueue. For this, the function keeps track of two values: + * + * msg_last_enqueued = index of the last enqueued message, + * msg_count = # of pending messages in the virtqueue. + * + * Context: Any context. Expects the tx/rx queue and the VirtIO substream + * spinlocks to be held by caller. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_pcm_msg_send(struct virtio_pcm_substream *vss) +{ + struct snd_pcm_runtime *runtime = vss->substream->runtime; + struct virtio_snd *snd = vss->snd; + struct virtio_device *vdev = snd->vdev; + struct virtqueue *vqueue = virtsnd_pcm_queue(vss)->vqueue; + int i; + int n; + bool notify = false; + + i = (vss->msg_last_enqueued + 1) % runtime->periods; + n = runtime->periods - vss->msg_count; + + for (; n; --n, i = (i + 1) % runtime->periods) { + struct virtio_pcm_msg *msg = vss->msgs[i]; + struct scatterlist *psgs[] = { + &msg->sgs[PCM_MSG_SG_XFER], + &msg->sgs[PCM_MSG_SG_DATA], + &msg->sgs[PCM_MSG_SG_STATUS] + }; + int rc; + + msg->xfer.stream_id = cpu_to_le32(vss->sid); + memset(&msg->status, 0, sizeof(msg->status)); + + if (vss->direction == SNDRV_PCM_STREAM_PLAYBACK) + rc = virtqueue_add_sgs(vqueue, psgs, 2, 1, msg, + GFP_ATOMIC); + else + rc = virtqueue_add_sgs(vqueue, psgs, 1, 2, msg, + GFP_ATOMIC); + + if (rc) { + dev_err(&vdev->dev, + "SID %u: failed to send I/O message\n", + vss->sid); + return rc; + } + + vss->msg_last_enqueued = i; + vss->msg_count++; + } + + if (!(vss->features & (1U << VIRTIO_SND_PCM_F_MSG_POLLING))) + notify = virtqueue_kick_prepare(vqueue); + + if (notify) + virtqueue_notify(vqueue); + + return 0; +} + +/** + * virtsnd_pcm_msg_pending_num() - Returns the number of pending I/O messages. + * @vss: VirtIO substream. + * + * Context: Any context. + * Return: Number of messages. + */ +unsigned int virtsnd_pcm_msg_pending_num(struct virtio_pcm_substream *vss) +{ + unsigned int num; + unsigned long flags; + + spin_lock_irqsave(&vss->lock, flags); + num = vss->msg_count; + spin_unlock_irqrestore(&vss->lock, flags); + + return num; +} + +/** + * virtsnd_pcm_msg_complete() - Complete an I/O message. + * @msg: I/O message. + * @written_bytes: Number of bytes written to the message. + * + * Completion of the message means the elapsed period. If transmission is + * allowed, then each completed message is immediately placed back at the end + * of the queue. + * + * For the playback substream, @written_bytes is equal to sizeof(msg->status). + * + * For the capture substream, @written_bytes is equal to sizeof(msg->status) + * plus the number of captured bytes. + * + * Context: Interrupt context. Takes and releases the VirtIO substream spinlock. + */ +static void virtsnd_pcm_msg_complete(struct virtio_pcm_msg *msg, + size_t written_bytes) +{ + struct virtio_pcm_substream *vss = msg->substream; + + /* + * hw_ptr always indicates the buffer position of the first I/O message + * in the virtqueue. Therefore, on each completion of an I/O message, + * the hw_ptr value is unconditionally advanced. + */ + spin_lock(&vss->lock); + /* + * If the capture substream returned an incorrect status, then just + * increase the hw_ptr by the message size. + */ + if (vss->direction == SNDRV_PCM_STREAM_PLAYBACK || + written_bytes <= sizeof(msg->status)) + vss->hw_ptr += msg->length; + else + vss->hw_ptr += written_bytes - sizeof(msg->status); + + if (vss->hw_ptr >= vss->buffer_bytes) + vss->hw_ptr -= vss->buffer_bytes; + + vss->xfer_xrun = false; + vss->msg_count--; + + if (vss->xfer_enabled) { + struct snd_pcm_runtime *runtime = vss->substream->runtime; + + runtime->delay = + bytes_to_frames(runtime, + le32_to_cpu(msg->status.latency_bytes)); + + schedule_work(&vss->elapsed_period); + + virtsnd_pcm_msg_send(vss); + } else if (!vss->msg_count) { + wake_up_all(&vss->msg_empty); + } + spin_unlock(&vss->lock); +} + +/** + * virtsnd_pcm_notify_cb() - Process all completed I/O messages. + * @queue: Underlying tx/rx virtqueue. + * + * Context: Interrupt context. Takes and releases the tx/rx queue spinlock. + */ +static inline void virtsnd_pcm_notify_cb(struct virtio_snd_queue *queue) +{ + struct virtio_pcm_msg *msg; + u32 written_bytes; + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + do { + virtqueue_disable_cb(queue->vqueue); + while ((msg = virtqueue_get_buf(queue->vqueue, &written_bytes))) + virtsnd_pcm_msg_complete(msg, written_bytes); + if (unlikely(virtqueue_is_broken(queue->vqueue))) + break; + } while (!virtqueue_enable_cb(queue->vqueue)); + spin_unlock_irqrestore(&queue->lock, flags); +} + +/** + * virtsnd_pcm_tx_notify_cb() - Process all completed TX messages. + * @vqueue: Underlying tx virtqueue. + * + * Context: Interrupt context. + */ +void virtsnd_pcm_tx_notify_cb(struct virtqueue *vqueue) +{ + struct virtio_snd *snd = vqueue->vdev->priv; + + virtsnd_pcm_notify_cb(virtsnd_tx_queue(snd)); +} + +/** + * virtsnd_pcm_rx_notify_cb() - Process all completed RX messages. + * @vqueue: Underlying rx virtqueue. + * + * Context: Interrupt context. + */ +void virtsnd_pcm_rx_notify_cb(struct virtqueue *vqueue) +{ + struct virtio_snd *snd = vqueue->vdev->priv; + + virtsnd_pcm_notify_cb(virtsnd_rx_queue(snd)); +} + +/** + * virtsnd_pcm_ctl_msg_alloc() - Allocate and initialize the PCM device control + * message for the specified substream. + * @vss: VirtIO PCM substream. + * @command: Control request code (VIRTIO_SND_R_PCM_XXX). + * @gfp: Kernel flags for memory allocation. + * + * Context: Any context. May sleep if @gfp flags permit. + * Return: Allocated message on success, NULL on failure. + */ +struct virtio_snd_msg * +virtsnd_pcm_ctl_msg_alloc(struct virtio_pcm_substream *vss, + unsigned int command, gfp_t gfp) +{ + size_t request_size = sizeof(struct virtio_snd_pcm_hdr); + size_t response_size = sizeof(struct virtio_snd_hdr); + struct virtio_snd_msg *msg; + + switch (command) { + case VIRTIO_SND_R_PCM_SET_PARAMS: + request_size = sizeof(struct virtio_snd_pcm_set_params); + break; + } + + msg = virtsnd_ctl_msg_alloc(request_size, response_size, gfp); + if (msg) { + struct virtio_snd_pcm_hdr *hdr = virtsnd_ctl_msg_request(msg); + + hdr->hdr.code = cpu_to_le32(command); + hdr->stream_id = cpu_to_le32(vss->sid); + } + + return msg; +} diff --git a/sound/virtio/virtio_pcm_ops.c b/sound/virtio/virtio_pcm_ops.c new file mode 100644 index 0000000000..f8bfb87624 --- /dev/null +++ b/sound/virtio/virtio_pcm_ops.c @@ -0,0 +1,464 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include <sound/pcm_params.h> + +#include "virtio_card.h" + +/* + * I/O messages lifetime + * --------------------- + * + * Allocation: + * Messages are initially allocated in the ops->hw_params() after the size and + * number of periods have been successfully negotiated. + * + * Freeing: + * Messages can be safely freed after the queue has been successfully flushed + * (RELEASE command in the ops->sync_stop()) and the ops->hw_free() has been + * called. + * + * When the substream stops, the ops->sync_stop() waits until the device has + * completed all pending messages. This wait can be interrupted either by a + * signal or due to a timeout. In this case, the device can still access + * messages even after calling ops->hw_free(). It can also issue an interrupt, + * and the interrupt handler will also try to access message structures. + * + * Therefore, freeing of already allocated messages occurs: + * + * - in ops->hw_params(), if this operator was called several times in a row, + * or if ops->hw_free() failed to free messages previously; + * + * - in ops->hw_free(), if the queue has been successfully flushed; + * + * - in dev->release(). + */ + +/* Map for converting ALSA format to VirtIO format. */ +struct virtsnd_a2v_format { + snd_pcm_format_t alsa_bit; + unsigned int vio_bit; +}; + +static const struct virtsnd_a2v_format g_a2v_format_map[] = { + { SNDRV_PCM_FORMAT_IMA_ADPCM, VIRTIO_SND_PCM_FMT_IMA_ADPCM }, + { SNDRV_PCM_FORMAT_MU_LAW, VIRTIO_SND_PCM_FMT_MU_LAW }, + { SNDRV_PCM_FORMAT_A_LAW, VIRTIO_SND_PCM_FMT_A_LAW }, + { SNDRV_PCM_FORMAT_S8, VIRTIO_SND_PCM_FMT_S8 }, + { SNDRV_PCM_FORMAT_U8, VIRTIO_SND_PCM_FMT_U8 }, + { SNDRV_PCM_FORMAT_S16_LE, VIRTIO_SND_PCM_FMT_S16 }, + { SNDRV_PCM_FORMAT_U16_LE, VIRTIO_SND_PCM_FMT_U16 }, + { SNDRV_PCM_FORMAT_S18_3LE, VIRTIO_SND_PCM_FMT_S18_3 }, + { SNDRV_PCM_FORMAT_U18_3LE, VIRTIO_SND_PCM_FMT_U18_3 }, + { SNDRV_PCM_FORMAT_S20_3LE, VIRTIO_SND_PCM_FMT_S20_3 }, + { SNDRV_PCM_FORMAT_U20_3LE, VIRTIO_SND_PCM_FMT_U20_3 }, + { SNDRV_PCM_FORMAT_S24_3LE, VIRTIO_SND_PCM_FMT_S24_3 }, + { SNDRV_PCM_FORMAT_U24_3LE, VIRTIO_SND_PCM_FMT_U24_3 }, + { SNDRV_PCM_FORMAT_S20_LE, VIRTIO_SND_PCM_FMT_S20 }, + { SNDRV_PCM_FORMAT_U20_LE, VIRTIO_SND_PCM_FMT_U20 }, + { SNDRV_PCM_FORMAT_S24_LE, VIRTIO_SND_PCM_FMT_S24 }, + { SNDRV_PCM_FORMAT_U24_LE, VIRTIO_SND_PCM_FMT_U24 }, + { SNDRV_PCM_FORMAT_S32_LE, VIRTIO_SND_PCM_FMT_S32 }, + { SNDRV_PCM_FORMAT_U32_LE, VIRTIO_SND_PCM_FMT_U32 }, + { SNDRV_PCM_FORMAT_FLOAT_LE, VIRTIO_SND_PCM_FMT_FLOAT }, + { SNDRV_PCM_FORMAT_FLOAT64_LE, VIRTIO_SND_PCM_FMT_FLOAT64 }, + { SNDRV_PCM_FORMAT_DSD_U8, VIRTIO_SND_PCM_FMT_DSD_U8 }, + { SNDRV_PCM_FORMAT_DSD_U16_LE, VIRTIO_SND_PCM_FMT_DSD_U16 }, + { SNDRV_PCM_FORMAT_DSD_U32_LE, VIRTIO_SND_PCM_FMT_DSD_U32 }, + { SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE, + VIRTIO_SND_PCM_FMT_IEC958_SUBFRAME } +}; + +/* Map for converting ALSA frame rate to VirtIO frame rate. */ +struct virtsnd_a2v_rate { + unsigned int rate; + unsigned int vio_bit; +}; + +static const struct virtsnd_a2v_rate g_a2v_rate_map[] = { + { 5512, VIRTIO_SND_PCM_RATE_5512 }, + { 8000, VIRTIO_SND_PCM_RATE_8000 }, + { 11025, VIRTIO_SND_PCM_RATE_11025 }, + { 16000, VIRTIO_SND_PCM_RATE_16000 }, + { 22050, VIRTIO_SND_PCM_RATE_22050 }, + { 32000, VIRTIO_SND_PCM_RATE_32000 }, + { 44100, VIRTIO_SND_PCM_RATE_44100 }, + { 48000, VIRTIO_SND_PCM_RATE_48000 }, + { 64000, VIRTIO_SND_PCM_RATE_64000 }, + { 88200, VIRTIO_SND_PCM_RATE_88200 }, + { 96000, VIRTIO_SND_PCM_RATE_96000 }, + { 176400, VIRTIO_SND_PCM_RATE_176400 }, + { 192000, VIRTIO_SND_PCM_RATE_192000 } +}; + +static int virtsnd_pcm_sync_stop(struct snd_pcm_substream *substream); + +/** + * virtsnd_pcm_open() - Open the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_open(struct snd_pcm_substream *substream) +{ + struct virtio_pcm *vpcm = snd_pcm_substream_chip(substream); + struct virtio_pcm_stream *vs = &vpcm->streams[substream->stream]; + struct virtio_pcm_substream *vss = vs->substreams[substream->number]; + + substream->runtime->hw = vss->hw; + substream->private_data = vss; + + snd_pcm_hw_constraint_integer(substream->runtime, + SNDRV_PCM_HW_PARAM_PERIODS); + + vss->stopped = !!virtsnd_pcm_msg_pending_num(vss); + vss->suspended = false; + + /* + * If the substream has already been used, then the I/O queue may be in + * an invalid state. Just in case, we do a check and try to return the + * queue to its original state, if necessary. + */ + return virtsnd_pcm_sync_stop(substream); +} + +/** + * virtsnd_pcm_close() - Close the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0. + */ +static int virtsnd_pcm_close(struct snd_pcm_substream *substream) +{ + return 0; +} + +/** + * virtsnd_pcm_dev_set_params() - Set the parameters of the PCM substream on + * the device side. + * @vss: VirtIO PCM substream. + * @buffer_bytes: Size of the hardware buffer. + * @period_bytes: Size of the hardware period. + * @channels: Selected number of channels. + * @format: Selected sample format (SNDRV_PCM_FORMAT_XXX). + * @rate: Selected frame rate. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_dev_set_params(struct virtio_pcm_substream *vss, + unsigned int buffer_bytes, + unsigned int period_bytes, + unsigned int channels, + snd_pcm_format_t format, + unsigned int rate) +{ + struct virtio_snd_msg *msg; + struct virtio_snd_pcm_set_params *request; + unsigned int i; + int vformat = -1; + int vrate = -1; + + for (i = 0; i < ARRAY_SIZE(g_a2v_format_map); ++i) + if (g_a2v_format_map[i].alsa_bit == format) { + vformat = g_a2v_format_map[i].vio_bit; + + break; + } + + for (i = 0; i < ARRAY_SIZE(g_a2v_rate_map); ++i) + if (g_a2v_rate_map[i].rate == rate) { + vrate = g_a2v_rate_map[i].vio_bit; + + break; + } + + if (vformat == -1 || vrate == -1) + return -EINVAL; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_SET_PARAMS, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + request = virtsnd_ctl_msg_request(msg); + request->buffer_bytes = cpu_to_le32(buffer_bytes); + request->period_bytes = cpu_to_le32(period_bytes); + request->channels = channels; + request->format = vformat; + request->rate = vrate; + + if (vss->features & (1U << VIRTIO_SND_PCM_F_MSG_POLLING)) + request->features |= + cpu_to_le32(1U << VIRTIO_SND_PCM_F_MSG_POLLING); + + if (vss->features & (1U << VIRTIO_SND_PCM_F_EVT_XRUNS)) + request->features |= + cpu_to_le32(1U << VIRTIO_SND_PCM_F_EVT_XRUNS); + + return virtsnd_ctl_msg_send_sync(vss->snd, msg); +} + +/** + * virtsnd_pcm_hw_params() - Set the parameters of the PCM substream. + * @substream: Kernel ALSA substream. + * @hw_params: Hardware parameters. + * + * Context: Process context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_device *vdev = vss->snd->vdev; + int rc; + + if (virtsnd_pcm_msg_pending_num(vss)) { + dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n", + vss->sid); + return -EBADFD; + } + + rc = virtsnd_pcm_dev_set_params(vss, params_buffer_bytes(hw_params), + params_period_bytes(hw_params), + params_channels(hw_params), + params_format(hw_params), + params_rate(hw_params)); + if (rc) + return rc; + + /* + * Free previously allocated messages if ops->hw_params() is called + * several times in a row, or if ops->hw_free() failed to free messages. + */ + virtsnd_pcm_msg_free(vss); + + return virtsnd_pcm_msg_alloc(vss, params_periods(hw_params), + params_period_bytes(hw_params)); +} + +/** + * virtsnd_pcm_hw_free() - Reset the parameters of the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0 + */ +static int virtsnd_pcm_hw_free(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + + /* If the queue is flushed, we can safely free the messages here. */ + if (!virtsnd_pcm_msg_pending_num(vss)) + virtsnd_pcm_msg_free(vss); + + return 0; +} + +/** + * virtsnd_pcm_prepare() - Prepare the PCM substream. + * @substream: Kernel ALSA substream. + * + * Context: Process context. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_prepare(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_device *vdev = vss->snd->vdev; + struct virtio_snd_msg *msg; + + if (!vss->suspended) { + if (virtsnd_pcm_msg_pending_num(vss)) { + dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n", + vss->sid); + return -EBADFD; + } + + vss->buffer_bytes = snd_pcm_lib_buffer_bytes(substream); + vss->hw_ptr = 0; + vss->msg_last_enqueued = -1; + } else { + struct snd_pcm_runtime *runtime = substream->runtime; + unsigned int buffer_bytes = snd_pcm_lib_buffer_bytes(substream); + unsigned int period_bytes = snd_pcm_lib_period_bytes(substream); + int rc; + + rc = virtsnd_pcm_dev_set_params(vss, buffer_bytes, period_bytes, + runtime->channels, + runtime->format, runtime->rate); + if (rc) + return rc; + } + + vss->xfer_xrun = false; + vss->suspended = false; + vss->msg_count = 0; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_PREPARE, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + return virtsnd_ctl_msg_send_sync(vss->snd, msg); +} + +/** + * virtsnd_pcm_trigger() - Process command for the PCM substream. + * @substream: Kernel ALSA substream. + * @command: Substream command (SNDRV_PCM_TRIGGER_XXX). + * + * Context: Any context. Takes and releases the VirtIO substream spinlock. + * May take and release the tx/rx queue spinlock. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_trigger(struct snd_pcm_substream *substream, int command) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_snd *snd = vss->snd; + struct virtio_snd_queue *queue; + struct virtio_snd_msg *msg; + unsigned long flags; + int rc; + + switch (command) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + queue = virtsnd_pcm_queue(vss); + + spin_lock_irqsave(&queue->lock, flags); + spin_lock(&vss->lock); + rc = virtsnd_pcm_msg_send(vss); + if (!rc) + vss->xfer_enabled = true; + spin_unlock(&vss->lock); + spin_unlock_irqrestore(&queue->lock, flags); + if (rc) + return rc; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_START, + GFP_KERNEL); + if (!msg) { + spin_lock_irqsave(&vss->lock, flags); + vss->xfer_enabled = false; + spin_unlock_irqrestore(&vss->lock, flags); + + return -ENOMEM; + } + + return virtsnd_ctl_msg_send_sync(snd, msg); + case SNDRV_PCM_TRIGGER_SUSPEND: + vss->suspended = true; + fallthrough; + case SNDRV_PCM_TRIGGER_STOP: + vss->stopped = true; + fallthrough; + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + spin_lock_irqsave(&vss->lock, flags); + vss->xfer_enabled = false; + spin_unlock_irqrestore(&vss->lock, flags); + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_STOP, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + return virtsnd_ctl_msg_send_sync(snd, msg); + default: + return -EINVAL; + } +} + +/** + * virtsnd_pcm_sync_stop() - Synchronous PCM substream stop. + * @substream: Kernel ALSA substream. + * + * The function can be called both from the upper level or from the driver + * itself. + * + * Context: Process context. Takes and releases the VirtIO substream spinlock. + * Return: 0 on success, -errno on failure. + */ +static int virtsnd_pcm_sync_stop(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_snd *snd = vss->snd; + struct virtio_snd_msg *msg; + unsigned int js = msecs_to_jiffies(virtsnd_msg_timeout_ms); + int rc; + + cancel_work_sync(&vss->elapsed_period); + + if (!vss->stopped) + return 0; + + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_RELEASE, + GFP_KERNEL); + if (!msg) + return -ENOMEM; + + rc = virtsnd_ctl_msg_send_sync(snd, msg); + if (rc) + return rc; + + /* + * The spec states that upon receipt of the RELEASE command "the device + * MUST complete all pending I/O messages for the specified stream ID". + * Thus, we consider the absence of I/O messages in the queue as an + * indication that the substream has been released. + */ + rc = wait_event_interruptible_timeout(vss->msg_empty, + !virtsnd_pcm_msg_pending_num(vss), + js); + if (rc <= 0) { + dev_warn(&snd->vdev->dev, "SID %u: failed to flush I/O queue\n", + vss->sid); + + return !rc ? -ETIMEDOUT : rc; + } + + vss->stopped = false; + + return 0; +} + +/** + * virtsnd_pcm_pointer() - Get the current hardware position for the PCM + * substream. + * @substream: Kernel ALSA substream. + * + * Context: Any context. Takes and releases the VirtIO substream spinlock. + * Return: Hardware position in frames inside [0 ... buffer_size) range. + */ +static snd_pcm_uframes_t +virtsnd_pcm_pointer(struct snd_pcm_substream *substream) +{ + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + snd_pcm_uframes_t hw_ptr = SNDRV_PCM_POS_XRUN; + unsigned long flags; + + spin_lock_irqsave(&vss->lock, flags); + if (!vss->xfer_xrun) + hw_ptr = bytes_to_frames(substream->runtime, vss->hw_ptr); + spin_unlock_irqrestore(&vss->lock, flags); + + return hw_ptr; +} + +/* PCM substream operators map. */ +const struct snd_pcm_ops virtsnd_pcm_ops = { + .open = virtsnd_pcm_open, + .close = virtsnd_pcm_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = virtsnd_pcm_hw_params, + .hw_free = virtsnd_pcm_hw_free, + .prepare = virtsnd_pcm_prepare, + .trigger = virtsnd_pcm_trigger, + .sync_stop = virtsnd_pcm_sync_stop, + .pointer = virtsnd_pcm_pointer, +}; |