The OASIS virtio spec defines a sound device type ID that is not present in the header yet.

Signed-off-by: Anton Yakovlev anton.yakovlev@opensynergy.com --- include/uapi/linux/virtio_ids.h | 1 + 1 file changed, 1 insertion(+)

diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h index bc1c0621f5ed..029a2e07a7f9 100644 --- a/include/uapi/linux/virtio_ids.h +++ b/include/uapi/linux/virtio_ids.h @@ -51,6 +51,7 @@ #define VIRTIO_ID_PSTORE 22 /* virtio pstore device */ #define VIRTIO_ID_IOMMU 23 /* virtio IOMMU */ #define VIRTIO_ID_MEM 24 /* virtio mem */ +#define VIRTIO_ID_SOUND 25 /* virtio sound */ #define VIRTIO_ID_FS 26 /* virtio filesystem */ #define VIRTIO_ID_PMEM 27 /* virtio pmem */ #define VIRTIO_ID_MAC80211_HWSIM 29 /* virtio mac80211-hwsim */

The control queue can be used by different parts of the driver to send commands to the device. Control messages can be either synchronous or asynchronous. The lifetime of a message is controlled by a reference count.

Introduce a module parameter to set the message completion timeout: msg_timeout_ms [=1000]

Signed-off-by: Anton Yakovlev anton.yakovlev@opensynergy.com --- sound/virtio/Makefile | 3 +- sound/virtio/virtio_card.c | 13 ++ sound/virtio/virtio_card.h | 7 + sound/virtio/virtio_ctl_msg.c | 310 ++++++++++++++++++++++++++++++++++ sound/virtio/virtio_ctl_msg.h | 78 +++++++++ 5 files changed, 410 insertions(+), 1 deletion(-) create mode 100644 sound/virtio/virtio_ctl_msg.c create mode 100644 sound/virtio/virtio_ctl_msg.h

diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile index 8c87ebb9982b..dc551e637441 100644 --- a/sound/virtio/Makefile +++ b/sound/virtio/Makefile @@ -3,5 +3,6 @@ obj-$(CONFIG_SND_VIRTIO) += virtio_snd.o

virtio_snd-objs := \ - virtio_card.o + virtio_card.o \ + virtio_ctl_msg.o

diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c index b5f63b5b7db4..c62b3a2da148 100644 --- a/sound/virtio/virtio_card.c +++ b/sound/virtio/virtio_card.c @@ -11,6 +11,10 @@

#include "virtio_card.h"

+int msg_timeout_ms = MSEC_PER_SEC; +module_param(msg_timeout_ms, int, 0644); +MODULE_PARM_DESC(msg_timeout_ms, "Message completion timeout in milliseconds"); + static void virtsnd_remove(struct virtio_device *vdev);

/** @@ -82,6 +86,7 @@ static int virtsnd_find_vqs(struct virtio_snd *snd) { struct virtio_device *vdev = snd->vdev; vq_callback_t *callbacks[VIRTIO_SND_VQ_MAX] = { + [VIRTIO_SND_VQ_CONTROL] = virtsnd_ctl_notify_cb, [VIRTIO_SND_VQ_EVENT] = virtsnd_event_notify_cb }; const char *names[VIRTIO_SND_VQ_MAX] = { @@ -218,6 +223,11 @@ static int virtsnd_validate(struct virtio_device *vdev) return -EINVAL; }

+ if (!msg_timeout_ms) { + dev_err(&vdev->dev, "msg_timeout_ms value cannot be zero\n"); + return -EINVAL; + } + return 0; }

@@ -240,6 +250,7 @@ static int virtsnd_probe(struct virtio_device *vdev)

snd->vdev = vdev; INIT_WORK(&snd->reset_work, virtsnd_reset_fn); + INIT_LIST_HEAD(&snd->ctl_msgs);

vdev->priv = snd;

@@ -278,6 +289,8 @@ static void virtsnd_remove(struct virtio_device *vdev) /* Stop all the virtqueues. */ vdev->config->reset(vdev);

+ virtsnd_ctl_msg_cancel_all(snd); + if (snd->card) snd_card_free(snd->card);

diff --git a/sound/virtio/virtio_card.h b/sound/virtio/virtio_card.h index 244381cc7a9b..c51a71a79388 100644 --- a/sound/virtio/virtio_card.h +++ b/sound/virtio/virtio_card.h @@ -11,6 +11,8 @@ #include <sound/core.h> #include <uapi/linux/virtio_snd.h>

+#include "virtio_ctl_msg.h" + #define VIRTIO_SND_CARD_DRIVER "virtio-snd" #define VIRTIO_SND_CARD_NAME "VirtIO SoundCard"

@@ -30,6 +32,7 @@ struct virtio_snd_queue { * @queues: Virtqueue wrappers. * @reset_work: Reset device work. * @card: ALSA sound card. + * @ctl_msgs: Pending control request list. * @event_msgs: Device events. */ struct virtio_snd { @@ -37,9 +40,13 @@ struct virtio_snd { 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; };

+/* 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) { diff --git a/sound/virtio/virtio_ctl_msg.c b/sound/virtio/virtio_ctl_msg.c new file mode 100644 index 000000000000..67a5a0301ba3 --- /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_request() - 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(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 000000000000..7f4db044f28e --- /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 */

The driver implements a message-based transport for I/O substream operations. Before the start of the substream, the hardware buffer is sliced into I/O messages, the number of which is equal to the current number of periods. The size of each message is equal to the current size of one period.

I/O messages are organized in an ordered queue. The completion of the I/O message indicates an elapsed period (the only exception is the end of the stream for the capture substream). Upon completion, the message is automatically re-added to the end of the queue.

Signed-off-by: Anton Yakovlev anton.yakovlev@opensynergy.com --- sound/virtio/Makefile | 3 +- sound/virtio/virtio_card.c | 18 +- sound/virtio/virtio_card.h | 9 + sound/virtio/virtio_pcm.c | 32 +++ sound/virtio/virtio_pcm.h | 42 ++++ sound/virtio/virtio_pcm_msg.c | 392 ++++++++++++++++++++++++++++++++++ 6 files changed, 493 insertions(+), 3 deletions(-) create mode 100644 sound/virtio/virtio_pcm_msg.c

diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile index 69162a545a41..626af3cc3ed7 100644 --- a/sound/virtio/Makefile +++ b/sound/virtio/Makefile @@ -5,5 +5,6 @@ obj-$(CONFIG_SND_VIRTIO) += virtio_snd.o virtio_snd-objs := \ virtio_card.o \ virtio_ctl_msg.o \ - virtio_pcm.o + virtio_pcm.o \ + virtio_pcm_msg.o

diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c index 235afc25fce7..a845978111d6 100644 --- a/sound/virtio/virtio_card.c +++ b/sound/virtio/virtio_card.c @@ -65,8 +65,16 @@ static void virtsnd_event_notify_cb(struct virtqueue *vqueue) spin_lock_irqsave(&queue->lock, flags); do { virtqueue_disable_cb(vqueue); - while ((event = virtqueue_get_buf(vqueue, &length))) + while ((event = virtqueue_get_buf(vqueue, &length))) { + switch (le32_to_cpu(event->hdr.code)) { + case VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED: + case VIRTIO_SND_EVT_PCM_XRUN: + virtsnd_pcm_event(snd, event); + break; + } + virtsnd_event_send(vqueue, event, true, GFP_ATOMIC); + } if (unlikely(virtqueue_is_broken(vqueue))) break; } while (!virtqueue_enable_cb(vqueue)); @@ -87,7 +95,9 @@ static int virtsnd_find_vqs(struct virtio_snd *snd) struct virtio_device *vdev = snd->vdev; 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_EVENT] = virtsnd_event_notify_cb, + [VIRTIO_SND_VQ_TX] = virtsnd_pcm_tx_notify_cb, + [VIRTIO_SND_VQ_RX] = virtsnd_pcm_rx_notify_cb }; const char *names[VIRTIO_SND_VQ_MAX] = { [VIRTIO_SND_VQ_CONTROL] = "virtsnd-ctl", @@ -299,6 +309,7 @@ static int virtsnd_probe(struct virtio_device *vdev) static void virtsnd_remove(struct virtio_device *vdev) { struct virtio_snd *snd = vdev->priv; + unsigned int i;

/* Stop all the virtqueues. */ vdev->config->reset(vdev); @@ -310,6 +321,9 @@ static void virtsnd_remove(struct virtio_device *vdev)

vdev->config->del_vqs(vdev);

+ for (i = 0; snd->substreams && i < snd->nsubstreams; ++i) + virtsnd_pcm_msg_free(&snd->substreams[i]); + kfree(snd->event_msgs); }

diff --git a/sound/virtio/virtio_card.h b/sound/virtio/virtio_card.h index f5e06a1ec033..3d8f5ad92f79 100644 --- a/sound/virtio/virtio_card.h +++ b/sound/virtio/virtio_card.h @@ -81,4 +81,13 @@ 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); +} + #endif /* VIRTIO_SND_CARD_H */ diff --git a/sound/virtio/virtio_pcm.c b/sound/virtio/virtio_pcm.c index 4348ead63c14..3cfd3520a9c0 100644 --- a/sound/virtio/virtio_pcm.c +++ b/sound/virtio/virtio_pcm.c @@ -337,6 +337,8 @@ int virtsnd_pcm_parse_cfg(struct virtio_snd *snd)

vss->snd = snd; vss->sid = i; + init_waitqueue_head(&vss->msg_empty); + spin_lock_init(&vss->lock);

rc = virtsnd_pcm_build_hw(vss, &info[i]); if (rc) @@ -461,3 +463,33 @@ int virtsnd_pcm_build_devs(struct virtio_snd *snd)

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 index a2aadc44dce9..c70e4fed9044 100644 --- a/sound/virtio/virtio_pcm.h +++ b/sound/virtio/virtio_pcm.h @@ -22,6 +22,19 @@ struct virtio_pcm_msg; * @features: Stream VirtIO feature bit map (1 << VIRTIO_SND_PCM_F_XXX). * @substream: Kernel ALSA substream. * @hw: Kernel ALSA substream hardware descriptor. + * @frame_bytes: Current frame size in bytes. + * @period_size: Current period size in frames. + * @buffer_size: Current buffer size in frames. + * @lock: Spinlock that protects fields shared by interrupt handlers and + * substream operators. + * @hw_ptr: Substream hardware pointer value in frames [0 ... buffer_size). + * @xfer_enabled: Data transfer state (0 - off, 1 - on). + * @xfer_xrun: Data underflow/overflow state (0 - no xrun, 1 - xrun). + * @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; @@ -31,6 +44,18 @@ struct virtio_pcm_substream { u32 features; struct snd_pcm_substream *substream; struct snd_pcm_hardware hw; + unsigned int frame_bytes; + snd_pcm_uframes_t period_size; + snd_pcm_uframes_t buffer_size; + spinlock_t lock; + snd_pcm_uframes_t hw_ptr; + bool xfer_enabled; + bool xfer_xrun; + struct virtio_pcm_msg **msgs; + unsigned int nmsgs; + int msg_last_enqueued; + unsigned int msg_count; + wait_queue_head_t msg_empty; };

/** @@ -63,8 +88,25 @@ 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); + #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 000000000000..8f29a9baf806 --- /dev/null +++ b/sound/virtio/virtio_pcm_msg.c @@ -0,0 +1,392 @@ +// 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. + * @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; + struct scatterlist sgs[0]; +}; + +/** + * 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; + + /* Free previously allocated messages (if any). */ + virtsnd_pcm_msg_free(vss); + + 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(sizeof(*msg) + sizeof(*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)); + 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; 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_complete() - Complete an I/O message. + * @msg: I/O message. + * @size: Number of bytes written. + * + * Completion of the message means the elapsed period. + * + * Context: Interrupt context. Takes and releases the VirtIO substream spinlock. + */ +static void virtsnd_pcm_msg_complete(struct virtio_pcm_msg *msg, size_t size) +{ + 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 period size. + */ + if (vss->direction == SNDRV_PCM_STREAM_PLAYBACK || + size <= sizeof(msg->status)) { + vss->hw_ptr += vss->period_size; + } else { + size -= sizeof(msg->status); + vss->hw_ptr += size / vss->frame_bytes; + } + + vss->hw_ptr %= vss->buffer_size; + 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)); + + spin_unlock(&vss->lock); + snd_pcm_period_elapsed(vss->substream); + spin_lock(&vss->lock); + + 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. + * + * If transmission is allowed, then each completed message is immediately placed + * back at the end of the queue. + * + * 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 length; + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + do { + virtqueue_disable_cb(queue->vqueue); + while ((msg = virtqueue_get_buf(queue->vqueue, &length))) + virtsnd_pcm_msg_complete(msg, length); + 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; +}

Introduce the operators required for the operation of substreams.

Signed-off-by: Anton Yakovlev anton.yakovlev@opensynergy.com --- sound/virtio/Makefile | 3 +- sound/virtio/virtio_pcm.c | 2 + sound/virtio/virtio_pcm.h | 4 + sound/virtio/virtio_pcm_ops.c | 469 ++++++++++++++++++++++++++++++++++ 4 files changed, 477 insertions(+), 1 deletion(-) create mode 100644 sound/virtio/virtio_pcm_ops.c

diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile index 626af3cc3ed7..34493226793f 100644 --- a/sound/virtio/Makefile +++ b/sound/virtio/Makefile @@ -6,5 +6,6 @@ virtio_snd-objs := \ virtio_card.o \ virtio_ctl_msg.o \ virtio_pcm.o \ - virtio_pcm_msg.o + virtio_pcm_msg.o \ + virtio_pcm_ops.o

diff --git a/sound/virtio/virtio_pcm.c b/sound/virtio/virtio_pcm.c index 3cfd3520a9c0..3605151860f2 100644 --- a/sound/virtio/virtio_pcm.c +++ b/sound/virtio/virtio_pcm.c @@ -454,6 +454,8 @@ int virtsnd_pcm_build_devs(struct virtio_snd *snd)

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, diff --git a/sound/virtio/virtio_pcm.h b/sound/virtio/virtio_pcm.h index c70e4fed9044..c48d00acee2e 100644 --- a/sound/virtio/virtio_pcm.h +++ b/sound/virtio/virtio_pcm.h @@ -35,6 +35,7 @@ struct virtio_pcm_msg; * @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. + * @msg_flushing: True if the I/O queue is in flushing state. */ struct virtio_pcm_substream { struct virtio_snd *snd; @@ -56,6 +57,7 @@ struct virtio_pcm_substream { int msg_last_enqueued; unsigned int msg_count; wait_queue_head_t msg_empty; + bool msg_flushing; };

/** @@ -82,6 +84,8 @@ struct virtio_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); diff --git a/sound/virtio/virtio_pcm_ops.c b/sound/virtio/virtio_pcm_ops.c new file mode 100644 index 000000000000..07510778b555 --- /dev/null +++ b/sound/virtio/virtio_pcm_ops.c @@ -0,0 +1,469 @@ +// 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" + +/* 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_substream *vss = NULL; + + if (vpcm) { + switch (substream->stream) { + case SNDRV_PCM_STREAM_PLAYBACK: + case SNDRV_PCM_STREAM_CAPTURE: { + struct virtio_pcm_stream *vs = + &vpcm->streams[substream->stream]; + + if (substream->number < vs->nsubstreams) + vss = vs->substreams[substream->number]; + break; + } + } + } + + if (!vss) + return -EBADFD; + + substream->runtime->hw = vss->hw; + substream->private_data = vss; + + snd_pcm_hw_constraint_integer(substream->runtime, + SNDRV_PCM_HW_PARAM_PERIODS); + + /* + * 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. + */ + vss->msg_flushing = true; + + 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_hw_params() - Set the parameters of the PCM substream. + * @substream: Kernel ALSA substream. + * @hw_params: Hardware parameters (can be NULL). + * + * The function can be called both from the upper level (in this case, + * @hw_params is not NULL) or from the driver itself (in this case, @hw_params + * is NULL, and the parameter values are taken from the runtime structure). + * + * 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 snd_pcm_runtime *runtime = substream->runtime; + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_device *vdev = vss->snd->vdev; + struct virtio_snd_msg *msg; + struct virtio_snd_pcm_set_params *request; + snd_pcm_format_t format; + unsigned int channels; + unsigned int rate; + unsigned int buffer_bytes; + unsigned int period_bytes; + unsigned int periods; + unsigned int i; + int vformat = -1; + int vrate = -1; + int rc; + + if (vss->msg_flushing) { + dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n", + vss->sid); + return -EBADFD; + } + + /* Set hardware parameters in device */ + if (hw_params) { + format = params_format(hw_params); + channels = params_channels(hw_params); + rate = params_rate(hw_params); + buffer_bytes = params_buffer_bytes(hw_params); + period_bytes = params_period_bytes(hw_params); + periods = params_periods(hw_params); + } else { + format = runtime->format; + channels = runtime->channels; + rate = runtime->rate; + buffer_bytes = frames_to_bytes(runtime, runtime->buffer_size); + period_bytes = frames_to_bytes(runtime, runtime->period_size); + periods = runtime->periods; + } + + 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); + + rc = virtsnd_ctl_msg_send_sync(vss->snd, msg); + if (rc) + return rc; + + return virtsnd_pcm_msg_alloc(vss, periods, period_bytes); +} + +/** + * 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) +{ + return 0; +} + +/** + * virtsnd_pcm_prepare() - Prepare the PCM substream. + * @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_prepare(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct virtio_pcm_substream *vss = snd_pcm_substream_chip(substream); + struct virtio_device *vdev = vss->snd->vdev; + struct virtio_snd_msg *msg; + unsigned long flags; + + if (vss->msg_flushing) { + dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n", + vss->sid); + return -EBADFD; + } + + spin_lock_irqsave(&vss->lock, flags); + /* + * Since I/O messages are asynchronous, they can be completed + * when the runtime structure no longer exists. Since each + * completion implies incrementing the hw_ptr, we cache all the + * current values needed to compute the new hw_ptr value. + */ + vss->frame_bytes = runtime->frame_bits >> 3; + vss->period_size = runtime->period_size; + vss->buffer_size = runtime->buffer_size; + + vss->hw_ptr = 0; + vss->xfer_xrun = false; + vss->msg_last_enqueued = -1; + vss->msg_count = 0; + spin_unlock_irqrestore(&vss->lock, flags); + + 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_msg *msg; + unsigned long flags; + int rc; + + switch (command) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: { + struct virtio_snd_queue *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_STOP: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: { + spin_lock_irqsave(&vss->lock, flags); + vss->xfer_enabled = false; + spin_unlock_irqrestore(&vss->lock, flags); + + /* + * The I/O queue needs to be flushed only when the substream is + * completely stopped. + */ + if (command == SNDRV_PCM_TRIGGER_STOP) + vss->msg_flushing = true; + + /* + * The STOP command can be issued in an atomic context after + * the drain is complete. Therefore, in general, we cannot sleep + * here. + */ + msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_STOP, + GFP_ATOMIC); + if (!msg) + return -ENOMEM; + + return virtsnd_ctl_msg_send_async(snd, msg); + } + default: { + return -EINVAL; + } + } +} + +/** + * virtsnd_pcm_msg_count() - Returns the number of pending I/O messages. + * @vss: VirtIO substream. + * + * Context: Any context. + * Return: Number of messages. + */ +static inline +unsigned int virtsnd_pcm_msg_count(struct virtio_pcm_substream *vss) +{ + unsigned int msg_count; + unsigned long flags; + + spin_lock_irqsave(&vss->lock, flags); + msg_count = vss->msg_count; + spin_unlock_irqrestore(&vss->lock, flags); + + return msg_count; +} + +/** + * 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(msg_timeout_ms); + int rc; + + if (!vss->msg_flushing) + return 0; + + if (!virtsnd_pcm_msg_count(vss)) + goto on_exit; + + 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_count(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; + } + +on_exit: + vss->msg_flushing = 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 = 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, +};

Enumerate all available PCM channel maps and create ALSA controls.

Signed-off-by: Anton Yakovlev anton.yakovlev@opensynergy.com --- sound/virtio/Makefile | 1 + sound/virtio/virtio_card.c | 10 ++ sound/virtio/virtio_card.h | 8 ++ sound/virtio/virtio_chmap.c | 219 ++++++++++++++++++++++++++++++++++++ sound/virtio/virtio_pcm.h | 4 + 5 files changed, 242 insertions(+) create mode 100644 sound/virtio/virtio_chmap.c

diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile index 09f485291285..2742bddb8874 100644 --- a/sound/virtio/Makefile +++ b/sound/virtio/Makefile @@ -4,6 +4,7 @@ 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 \ diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c index 4578d0ce0726..787a4dec1da8 100644 --- a/sound/virtio/virtio_card.c +++ b/sound/virtio/virtio_card.c @@ -222,6 +222,10 @@ static int virtsnd_build_devs(struct virtio_snd *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) @@ -234,6 +238,12 @@ static int virtsnd_build_devs(struct virtio_snd *snd) return rc; }

+ if (snd->nchmaps) { + rc = virtsnd_chmap_build_devs(snd); + if (rc) + return rc; + } + return snd_card_register(snd->card); }

diff --git a/sound/virtio/virtio_card.h b/sound/virtio/virtio_card.h index 37896a030e10..817508b3e9b4 100644 --- a/sound/virtio/virtio_card.h +++ b/sound/virtio/virtio_card.h @@ -44,6 +44,8 @@ struct virtio_snd_queue { * @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; @@ -57,6 +59,8 @@ struct virtio_snd { u32 njacks; struct virtio_pcm_substream *substreams; u32 nsubstreams; + struct virtio_snd_chmap_info *chmaps; + u32 nchmaps; };

/* Message completion timeout in milliseconds (module parameter). */ @@ -102,4 +106,8 @@ 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 000000000000..5bc924933a59 --- /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_pcm.h b/sound/virtio/virtio_pcm.h index c48d00acee2e..379052e2fbf9 100644 --- a/sound/virtio/virtio_pcm.h +++ b/sound/virtio/virtio_pcm.h @@ -64,10 +64,14 @@ struct virtio_pcm_substream { * 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; };

/**