+
+ if (snd->card)
+ snd_card_free(snd->card);
+
+ vdev->config->reset(vdev);
+ vdev->config->del_vqs(vdev);
+
+ list_for_each_entry_safe(pcm, pcm_next, &snd->pcm_list, list) {
+ unsigned int i;
+
+ list_del(&pcm->list);
+
+ for (i = 0; i < ARRAY_SIZE(pcm->streams); ++i) {
+ struct virtio_pcm_stream *stream = &pcm->streams[i];
+
+ if (stream->substreams)
+ devm_kfree(&vdev->dev, stream->substreams);
+ }
+
+ devm_kfree(&vdev->dev, pcm);
+ }
+
+ if (snd->substreams)
+ devm_kfree(&vdev->dev, snd->substreams);
+
+ devm_kfree(&vdev->dev, snd);
+
+ vdev->priv = NULL;
+}
+
+/**
+ * virtsnd_config_changed() - Handle configuration change notification.
+ * @vdev: VirtIO parent device.
+ *
+ * This callback function is called upon a configuration change interrupt
+ * request from the device. Currently only used to handle NEEDS_RESET device
+ * status.
+ *
+ * Context: Interrupt context.
+ */
+static void virtsnd_config_changed(struct virtio_device *vdev)
+{
+ struct virtio_snd *snd = vdev->priv;
+ unsigned int status = vdev->config->get_status(vdev);
+
+ if (status & VIRTIO_CONFIG_S_NEEDS_RESET)
+ schedule_work(&snd->reset_work);
+ else
+ dev_warn(&vdev->dev,
+ "sound device configuration was changed\n");
+}
+
+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,
+ .config_changed = virtsnd_config_changed,
+};
+
+static int __init init(void)
+{
+ return register_virtio_driver(&virtsnd_driver);
+}
+module_init(init);
+
+static void __exit fini(void)
+{
+ unregister_virtio_driver(&virtsnd_driver);
+}
+module_exit(fini);
+
+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 000000000000..be6651a6aaf8
--- /dev/null
+++ b/sound/virtio/virtio_card.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Sound card driver for virtio
+ * Copyright (C) 2020 OpenSynergy GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef VIRTIO_SND_CARD_H
+#define VIRTIO_SND_CARD_H
+
+#include <linux/virtio.h>
+#include <sound/core.h>
+#include <uapi/linux/virtio_snd.h>
+
+#include "virtio_ctl_msg.h"
+#include "virtio_pcm.h"
+
+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.
+ * @reset_work: Reset device work.
+ * @card: ALSA sound card.
+ * @ctl_msgs: Pending control request list.
+ * @event_msgs: Device events.
+ * @pcm_list: VirtIO PCM device list.
+ * @substreams: VirtIO PCM substreams.
+ * @nsubstreams: Number of PCM substreams.
+ */
+struct virtio_snd {
+ struct virtio_device *vdev;
+ struct virtio_snd_queue queues[VIRTIO_SND_VQ_MAX];
+ struct work_struct reset_work;
+ struct snd_card *card;
+ struct list_head ctl_msgs;
+ struct virtio_snd_event *event_msgs;
+ struct list_head pcm_list;
+ struct virtio_pcm_substream *substreams;
+ unsigned int nsubstreams;
+};
+
+/* Message completion timeout in milliseconds (module parameter). */
+extern int 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];
+}
+
+#endif /* VIRTIO_SND_CARD_H */
diff --git a/sound/virtio/virtio_ctl_msg.c b/sound/virtio/virtio_ctl_msg.c
new file mode 100644
index 000000000000..c1701756bc32
--- /dev/null
+++ b/sound/virtio/virtio_ctl_msg.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Sound card driver for virtio
+ * Copyright (C) 2020 OpenSynergy GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/moduleparam.h>
+#include <linux/virtio_config.h>
+
+#include "virtio_card.h"
+#include "virtio_ctl_msg.h"
+
+/**
+ * virtsnd_ctl_msg_alloc_ext() - Allocate and initialize a control message.
+ * @vdev: VirtIO parent device.
+ * @request_size: Size of request header (pointed to by sg_request field).
+ * @response_size: Size of response header (pointed to by sg_response field).
+ * @sgs: Additional data to attach to the message (may be NULL).
+ * @out_sgs: Number of scattergather elements to attach to the request header.
+ * @in_sgs: Number of scattergather elements to attach to the 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, ERR_PTR(-errno) on failure.
+ */
+struct virtio_snd_msg *virtsnd_ctl_msg_alloc_ext(struct virtio_device *vdev,
+ size_t request_size,
+ size_t response_size,
+ struct scatterlist *sgs,
+ unsigned int out_sgs,
+ unsigned int in_sgs, gfp_t gfp)
+{
+ struct virtio_snd_msg *msg;
+ size_t msg_size =
+ sizeof(*msg) + (1 + out_sgs + 1 + in_sgs) * sizeof(*msg->sgs);
+ unsigned int i;
+
+ msg = devm_kzalloc(&vdev->dev, msg_size + request_size + response_size,
+ gfp);
+ if (!msg)
+ return ERR_PTR(-ENOMEM);
+
+ sg_init_one(&msg->sg_request, (u8 *)msg + msg_size, request_size);
+ sg_init_one(&msg->sg_response, (u8 *)msg + msg_size + request_size,
+ response_size);
+
+ INIT_LIST_HEAD(&msg->list);
+ init_completion(&msg->notify);
+ atomic_set(&msg->ref_count, 1);
+
+ msg->sgs[msg->out_sgs++] = &msg->sg_request;
+ if (sgs)
+ for (i = 0; i < out_sgs; ++i)
+ msg->sgs[msg->out_sgs++] = &sgs[i];
+
+ msg->sgs[msg->out_sgs + msg->in_sgs++] = &msg->sg_response;
+ if (sgs)
+ for (i = out_sgs; i < out_sgs + in_sgs; ++i)
+ msg->sgs[msg->out_sgs + msg->in_sgs++] = &sgs[i];
+
+ return msg;
+}
+
+/**
+ * virtsnd_ctl_msg_send() - Send an (asynchronous) control message.
+ * @snd: VirtIO sound device.
+ * @msg: Control message.
+ *
+ * If a message is failed to be enqueued, it will be deleted. If message content
+ * is still needed, the caller must additionally to virtsnd_ctl_msg_ref/unref()
+ * it.
+ *
+ * Context: Any context. Takes and releases the control queue spinlock.
+ * Return: 0 on success, -errno on failure.
+ */
+int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg)
+{
+ struct virtio_device *vdev = snd->vdev;
+ struct virtio_snd_queue *queue = virtsnd_control_queue(snd);
+ struct virtio_snd_hdr *response = sg_virt(&msg->sg_response);
+ bool notify = false;
+ unsigned long flags;
+ int rc = -EIO;
+
+ /* Set the default status in case the message was not sent or was
+ * canceled.
+ */
+ response->code = cpu_to_virtio32(vdev, VIRTIO_SND_S_IO_ERR);
+
+ spin_lock_irqsave(&queue->lock, flags);
+ if (queue->vqueue) {
+ rc = virtqueue_add_sgs(queue->vqueue, msg->sgs, msg->out_sgs,
+ msg->in_sgs, 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) {
+ if (!notify || virtqueue_notify(queue->vqueue))
+ return 0;
+
+ spin_lock_irqsave(&queue->lock, flags);
+ list_del(&msg->list);
+ spin_unlock_irqrestore(&queue->lock, flags);
+ }
+
+ virtsnd_ctl_msg_unref(snd->vdev, msg);
+
+ return -EIO;
+}
+
+/**
+ * virtsnd_ctl_msg_send_sync() - Send a (synchronous) control 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. Takes and releases the control queue spinlock.
+ * 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.
+ */
+int virtsnd_ctl_msg_send_sync(struct virtio_snd *snd,
+ struct virtio_snd_msg *msg)
+{
+ struct virtio_device *vdev = snd->vdev;
+ unsigned int js = msecs_to_jiffies(msg_timeout_ms);
+ struct virtio_snd_hdr *response;
+ int rc;
+
+ virtsnd_ctl_msg_ref(vdev, msg);
+
+ rc = virtsnd_ctl_msg_send(snd, msg);
+ if (rc)
+ goto on_failure;
+
+ rc = wait_for_completion_interruptible_timeout(&msg->notify, js);
+ if (rc <= 0) {
+ if (!rc) {
+ struct virtio_snd_hdr *request =
+ sg_virt(&msg->sg_request);
+
+ dev_err(&vdev->dev,
+ "control message (0x%08x) timeout\n",
+ le32_to_cpu(request->code));
+ rc = -EIO;
+ }
+
+ goto on_failure;
+ }
+
+ response = sg_virt(&msg->sg_response);
+
+ switch (le32_to_cpu(response->code)) {
+ case VIRTIO_SND_S_OK:
+ rc = 0;
+ break;
+ case VIRTIO_SND_S_BAD_MSG:
+ rc = -EINVAL;
+ break;
+ case VIRTIO_SND_S_NOT_SUPP:
+ rc = -EOPNOTSUPP;
+ break;
+ case VIRTIO_SND_S_IO_ERR:
+ rc = -EIO;
+ break;
+ default:
+ rc = -EPERM;
+ break;
+ }
+
+on_failure:
+ virtsnd_ctl_msg_unref(vdev, msg);
+
+ return rc;
+}
+
+/**
+ * virtsnd_ctl_msg_complete() - Complete a control message.
+ * @snd: VirtIO sound device.
+ * @msg: Control message.
+ *
+ * Context: Any context.
+ */
+void virtsnd_ctl_msg_complete(struct virtio_snd *snd,
+ struct virtio_snd_msg *msg)
+{
+ list_del(&msg->list);
+ complete(&msg->notify);
+
+ virtsnd_ctl_msg_unref(snd->vdev, msg);
+}
+
+/**
+ * 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_device *vdev = snd->vdev;
+ struct virtio_snd_msg *msg;
+ struct virtio_snd_query_info *query;
+ struct scatterlist sg;
+
+ sg_init_one(&sg, info, count * size);
+
+ msg = virtsnd_ctl_msg_alloc_ext(vdev, sizeof(*query),
+ sizeof(struct virtio_snd_hdr), &sg, 0,
+ 1, GFP_KERNEL);
+ if (IS_ERR(msg))
+ return PTR_ERR(msg);
+
+ query = sg_virt(&msg->sg_request);
+ query->hdr.code = cpu_to_virtio32(vdev, command);
+ query->start_id = cpu_to_virtio32(vdev, start_id);
+ query->count = cpu_to_virtio32(vdev, count);
+ query->size = cpu_to_virtio32(vdev, size);
+
+ return virtsnd_ctl_msg_send_sync(snd, msg);
+}
+
+/**
+ * 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);
+ unsigned long flags;
+
+ spin_lock_irqsave(&queue->lock, flags);
+ while (queue->vqueue) {
+ virtqueue_disable_cb(queue->vqueue);
+
+ for (;;) {
+ struct virtio_snd_msg *msg;
+ u32 length;
+
+ msg = virtqueue_get_buf(queue->vqueue, &length);
+ if (!msg)
+ break;
+
+ virtsnd_ctl_msg_complete(snd, msg);
+ }
+
+ if (unlikely(virtqueue_is_broken(queue->vqueue)))
+ break;
+
+ if (virtqueue_enable_cb(queue->vqueue))
+ break;
+ }
+ 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 000000000000..0f8de8f2fd2d
--- /dev/null
+++ b/sound/virtio/virtio_ctl_msg.h
@@ -0,0 +1,122 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Sound card driver for virtio
+ * Copyright (C) 2020 OpenSynergy GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#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 - Control message.
+ * @sg_request: Scattergather element containing a device request (header).
+ * @sg_response: Scattergather element containing a device response (status).
+ * @list: Pending message list entry.
+ * @notify: Request completed notification.
+ * @ref_count: Reference count used to manage a message lifetime.
+ * @out_sgs: Number of read-only sg elements in the sgs array.
+ * @in_sgs: Number of write-only sg elements in the sgs array.
+ * @sgs: Array of sg elements to add to the control virtqueue.
+ */
+struct virtio_snd_msg {
+/* public: */
+ struct scatterlist sg_request;
+ struct scatterlist sg_response;
+/* private: internal use only */
+ struct list_head list;
+ struct completion notify;
+ atomic_t ref_count;
+ unsigned int out_sgs;
+ unsigned int in_sgs;
+ struct scatterlist *sgs[0];
+};
+
+/**
+ * virtsnd_ctl_msg_ref() - Increment reference counter for the message.
+ * @vdev: VirtIO parent device.
+ * @msg: Control message.
+ *
+ * Context: Any context.
+ */
+static inline void virtsnd_ctl_msg_ref(struct virtio_device *vdev,
+ struct virtio_snd_msg *msg)
+{
+ atomic_inc(&msg->ref_count);
+}
+
+/**
+ * virtsnd_ctl_msg_unref() - Decrement reference counter for the message.
+ * @vdev: VirtIO parent device.
+ * @msg: Control message.
+ *
+ * The message will be freed when the ref_count value is 0.
+ *
+ * Context: Any context.
+ */
+static inline void virtsnd_ctl_msg_unref(struct virtio_device *vdev,
+ struct virtio_snd_msg *msg)
+{
+ if (!atomic_dec_return(&msg->ref_count))
+ devm_kfree(&vdev->dev, msg);
+}
+
+struct virtio_snd_msg *virtsnd_ctl_msg_alloc_ext(struct virtio_device *vdev,
+ size_t request_size,
+ size_t response_size,
+ struct scatterlist *sgs,
+ unsigned int out_sgs,
+ unsigned int in_sgs,
+ gfp_t gfp);
+
+/**
+ * virtsnd_ctl_msg_alloc() - Simplified control message allocation.
+ * @vdev: VirtIO parent device.
+ * @request_size: Size of request header (pointed to by sg_request field).
+ * @response_size: Size of response header (pointed to by sg_response field).
+ * @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, ERR_PTR(-errno) on failure.
+ */
+static inline
+struct virtio_snd_msg *virtsnd_ctl_msg_alloc(struct virtio_device *vdev,
+ size_t request_size,
+ size_t response_size, gfp_t gfp)
+{
+ return virtsnd_ctl_msg_alloc_ext(vdev, request_size, response_size,
+ NULL, 0, 0, gfp);
+}
+
+int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg);
+
+int virtsnd_ctl_msg_send_sync(struct virtio_snd *snd,
+ struct virtio_snd_msg *msg);
+
+void virtsnd_ctl_msg_complete(struct virtio_snd *snd,
+ 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_pcm.c b/sound/virtio/virtio_pcm.c
new file mode 100644
index 000000000000..036990b7b78a
--- /dev/null
+++ b/sound/virtio/virtio_pcm.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Sound card driver for virtio
+ * Copyright (C) 2020 OpenSynergy GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/moduleparam.h>
+#include <linux/virtio_config.h>
+
+#include "virtio_card.h"
+
+static unsigned int pcm_buffer_ms = 160;
+module_param(pcm_buffer_ms, uint, 0644);
+MODULE_PARM_DESC(pcm_buffer_ms, "PCM substream buffer time in milliseconds");
+
+static unsigned int pcm_periods_min = 2;
+module_param(pcm_periods_min, uint, 0644);
+MODULE_PARM_DESC(pcm_periods_min, "Minimum number of PCM periods");
+
+static unsigned int pcm_periods_max = 16;
+module_param(pcm_periods_max, uint, 0644);
+MODULE_PARM_DESC(pcm_periods_max, "Maximum number of PCM periods");
+
+static unsigned int 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 unsigned int 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 unsigned int 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.
+ * @substream: 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 *substream,
+ struct virtio_snd_pcm_info *info)
+{
+ struct virtio_device *vdev = substream->snd->vdev;
+ unsigned int i;
+ u64 values;
+ size_t sample_max = 0;
+ size_t sample_min = 0;
+
+ substream->features = le32_to_cpu(info->features);
+
+ /*
+ * TODO: set SNDRV_PCM_INFO_{BATCH,BLOCK_TRANSFER} if device supports
+ * only message-based transport.
+ */
+ substream->hw.info =
+ SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_BATCH |
+ SNDRV_PCM_INFO_BLOCK_TRANSFER |
+ SNDRV_PCM_INFO_INTERLEAVED;
+
+ if (!info->channels_min || info->channels_min > info->channels_max) {
+ dev_err(&vdev->dev,
+ "SID %u: invalid channel range [%u %u]\n",
+ substream->sid, info->channels_min, info->channels_max);
+ return -EINVAL;
+ }
+
+ substream->hw.channels_min = info->channels_min;
+ substream->hw.channels_max = info->channels_max;
+
+ values = le64_to_cpu(info->formats);
+
+ substream->hw.formats = 0;
+
+ for (i = 0; i < ARRAY_SIZE(g_v2a_format_map); ++i)
+ if (values & (1ULL << i)) {
+ unsigned int 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;
+
+ substream->hw.formats |= (1ULL << alsa_fmt);
+ }
+
+ if (!substream->hw.formats) {
+ dev_err(&vdev->dev,
+ "SID %u: no supported PCM sample formats found\n",
+ substream->sid);
+ return -EINVAL;
+ }
+
+ values = le64_to_cpu(info->rates);
+
+ substream->hw.rates = 0;
+
+ for (i = 0; i < ARRAY_SIZE(g_v2a_rate_map); ++i)
+ if (values & (1ULL << i)) {
+ if (!substream->hw.rate_min ||
+ substream->hw.rate_min > g_v2a_rate_map[i].rate)
+ substream->hw.rate_min = g_v2a_rate_map[i].rate;
+
+ if (substream->hw.rate_max < g_v2a_rate_map[i].rate)
+ substream->hw.rate_max = g_v2a_rate_map[i].rate;
+
+ substream->hw.rates |= g_v2a_rate_map[i].alsa_bit;
+ }
+
+ if (!substream->hw.rates) {
+ dev_err(&vdev->dev,
+ "SID %u: no supported PCM frame rates found\n",
+ substream->sid);
+ return -EINVAL;
+ }
+
+ substream->hw.periods_min = pcm_periods_min;
+ substream->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.
+ */
+ substream->hw.buffer_bytes_max =
+ sample_max * substream->hw.channels_max * pcm_buffer_ms *
+ (substream->hw.rate_max / MSEC_PER_SEC);
+
+ /* Align the buffer size to the page size */
+ substream->hw.buffer_bytes_max =
+ (substream->hw.buffer_bytes_max + PAGE_SIZE - 1) & -PAGE_SIZE;
+
+ /*
+ * 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.
+ */
+ substream->hw.period_bytes_min =
+ sample_min * substream->hw.channels_min * pcm_period_ms_min *
+ (substream->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).
+ */
+ substream->hw.period_bytes_max =
+ sample_max * substream->hw.channels_max * pcm_period_ms_max *
+ (substream->hw.rate_max / MSEC_PER_SEC);
+
+ return 0;
+}
+
+/**
+ * virtsnd_pcm_prealloc_pages() - Preallocate substream hardware buffer.
+ * @substream: VirtIO substream.
+ *
+ * Context: Any context that permits to sleep.
+ * Return: 0 on success, -errno on failure.
+ */
+static int virtsnd_pcm_prealloc_pages(struct virtio_pcm_substream *substream)
+{
+ struct snd_pcm_substream *ksubstream = substream->substream;
+ size_t size = substream->hw.buffer_bytes_max;
+ struct device *data = snd_dma_continuous_data(GFP_KERNEL);
+
+ /*
+ * We just allocate a CONTINUOUS buffer as it should work in any setup.
+ *
+ * If there is a need to use DEV(_XXX), then add this case here and
+ * (probably) update the related source code in other places.
+ */
+ snd_pcm_lib_preallocate_pages(ksubstream, SNDRV_DMA_TYPE_CONTINUOUS,
+ data, size, size);
+
+ 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, unsigned int nid)
+{
+ struct virtio_pcm *pcm;
+
+ list_for_each_entry(pcm, &snd->pcm_list, list)
+ if (pcm->nid == nid)
+ return pcm;
+
+ 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,
+ unsigned int nid)
+{
+ struct virtio_device *vdev = snd->vdev;
+ struct virtio_pcm *pcm;
+
+ pcm = virtsnd_pcm_find(snd, nid);
+ if (!IS_ERR(pcm))
+ return pcm;
+
+ pcm = devm_kzalloc(&vdev->dev, sizeof(*pcm), GFP_KERNEL);
+ if (!pcm)
+ return ERR_PTR(-ENOMEM);
+
+ pcm->nid = nid;
+ list_add_tail(&pcm->list, &snd->pcm_list);
+
+ return pcm;
+}
+
+/**
+ * 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_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;
+ unsigned int i;
+ int rc;
+
+ virtio_cread(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 = devm_kcalloc(&vdev->dev, 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)
+ return rc;
+
+ for (i = 0; i < snd->nsubstreams; ++i) {
+ struct virtio_pcm_substream *substream = &snd->substreams[i];
+ struct virtio_pcm *pcm;
+
+ substream->snd = snd;
+ substream->sid = i;
+
+ rc = virtsnd_pcm_build_hw(substream, &info[i]);
+ if (rc)
+ return rc;
+
+ substream->nid = le32_to_cpu(info[i].hdr.hda_fn_nid);
+
+ pcm = virtsnd_pcm_find_or_create(snd, substream->nid);
+ if (IS_ERR(pcm))
+ return PTR_ERR(pcm);
+
+ switch (info[i].direction) {
+ case VIRTIO_SND_D_OUTPUT: {
+ substream->direction = SNDRV_PCM_STREAM_PLAYBACK;
+ break;
+ }
+ case VIRTIO_SND_D_INPUT: {
+ substream->direction = SNDRV_PCM_STREAM_CAPTURE;
+ break;
+ }
+ default: {
+ dev_err(&vdev->dev, "SID %u: unknown direction (%u)\n",
+ substream->sid, info[i].direction);
+ return -EINVAL;
+ }
+ }
+
+ pcm->streams[substream->direction].nsubstreams++;
+ }
+
+ devm_kfree(&vdev->dev, info);
+
+ return 0;
+}
+
+/**
+ * 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 *pcm;
+ unsigned int i;
+ int rc;
+
+ list_for_each_entry(pcm, &snd->pcm_list, list) {
+ unsigned int npbs =
+ pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].nsubstreams;
+ unsigned int ncps =
+ pcm->streams[SNDRV_PCM_STREAM_CAPTURE].nsubstreams;
+
+ if (!npbs && !ncps)
+ continue;
+
+ rc = snd_pcm_new(snd->card, "virtio_snd", pcm->nid, npbs, ncps,
+ &pcm->pcm);
+ if (rc) {
+ dev_err(&vdev->dev, "snd_pcm_new[%u] failed: %d\n",
+ pcm->nid, rc);
+ return rc;
+ }
+
+ pcm->pcm->info_flags = 0;
+ pcm->pcm->dev_class = SNDRV_PCM_CLASS_GENERIC;
+ pcm->pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
+ strscpy(pcm->pcm->name, "VirtIO PCM", sizeof(pcm->pcm->name));
+
+ pcm->pcm->private_data = pcm;
+
+ for (i = 0; i < ARRAY_SIZE(pcm->streams); ++i) {
+ struct virtio_pcm_stream *stream = &pcm->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_substream *substream = &snd->substreams[i];
+ struct virtio_pcm_stream *stream;
+
+ pcm = virtsnd_pcm_find(snd, substream->nid);
+ if (IS_ERR(pcm))
+ return PTR_ERR(pcm);
+
+ stream = &pcm->streams[substream->direction];
+ stream->substreams[stream->nsubstreams++] = substream;
+ }
+
+ list_for_each_entry(pcm, &snd->pcm_list, list)
+ for (i = 0; i < ARRAY_SIZE(pcm->streams); ++i) {
+ struct virtio_pcm_stream *stream = &pcm->streams[i];
+ struct snd_pcm_str *kstream;
+ struct snd_pcm_substream *ksubstream;
+
+ if (!stream->nsubstreams)
+ continue;
+
+ kstream = &pcm->pcm->streams[i];
+ ksubstream = kstream->substream;
+
+ while (ksubstream) {
+ struct virtio_pcm_substream *substream =
+ stream->substreams[ksubstream->number];
+
+ substream->substream = ksubstream;
+ ksubstream = ksubstream->next;
+
+ rc = virtsnd_pcm_prealloc_pages(substream);
+ if (rc)
+ return rc;
+ }
+ }
+
+ 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 *substream;
+ unsigned int sid = le32_to_cpu(event->data);
+
+ if (sid >= snd->nsubstreams)
+ return;
+
+ substream = &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: {
+ break;
+ }
+ }
+}
diff --git a/sound/virtio/virtio_pcm.h b/sound/virtio/virtio_pcm.h
new file mode 100644
index 000000000000..73fb4d9dc524
--- /dev/null
+++ b/sound/virtio/virtio_pcm.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Sound card driver for virtio
+ * Copyright (C) 2020 OpenSynergy GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#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_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.
+ */
+struct virtio_pcm_substream {
+ struct virtio_snd *snd;
+ unsigned int nid;
+ unsigned int sid;
+ u32 direction;
+ u32 features;
+ struct snd_pcm_substream *substream;
+ struct snd_pcm_hardware hw;
+};
+
+/**
+ * struct virtio_pcm_stream - VirtIO PCM stream.
+ * @substreams: Virtio substreams belonging to the stream.
+ * @nsubstreams: Number of substreams.
+ */
+struct virtio_pcm_stream {
+ struct virtio_pcm_substream **substreams;
+ unsigned int nsubstreams;
+};
+
+/**
+ * struct virtio_pcm - VirtIO PCM device.
+ * @list: 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;
+ unsigned int nid;
+ struct snd_pcm *pcm;
+ struct virtio_pcm_stream streams[SNDRV_PCM_STREAM_LAST + 1];
+};
+
+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, unsigned int nid);
+
+struct virtio_pcm *virtsnd_pcm_find_or_create(struct virtio_snd *snd,
+ unsigned int nid);
+
+#endif /* VIRTIO_SND_PCM_H */
--
2.30.0
