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Diffstat (limited to 'meta-agl-bsp/virtualization-layer/recipes-kernel/linux/linux-yocto/virtio-kmeta/bsp/virtio/virtio-snd/0002-ALSA-virtio-add-virtio-sound-driver.patch')
-rw-r--r--meta-agl-bsp/virtualization-layer/recipes-kernel/linux/linux-yocto/virtio-kmeta/bsp/virtio/virtio-snd/0002-ALSA-virtio-add-virtio-sound-driver.patch849
1 files changed, 849 insertions, 0 deletions
diff --git a/meta-agl-bsp/virtualization-layer/recipes-kernel/linux/linux-yocto/virtio-kmeta/bsp/virtio/virtio-snd/0002-ALSA-virtio-add-virtio-sound-driver.patch b/meta-agl-bsp/virtualization-layer/recipes-kernel/linux/linux-yocto/virtio-kmeta/bsp/virtio/virtio-snd/0002-ALSA-virtio-add-virtio-sound-driver.patch
new file mode 100644
index 000000000..e2f80442f
--- /dev/null
+++ b/meta-agl-bsp/virtualization-layer/recipes-kernel/linux/linux-yocto/virtio-kmeta/bsp/virtio/virtio-snd/0002-ALSA-virtio-add-virtio-sound-driver.patch
@@ -0,0 +1,849 @@
+From a1cde5ccba57562aa77739b63b50586e6b197b52 Mon Sep 17 00:00:00 2001
+From: Anton Yakovlev <anton.yakovlev@opensynergy.com>
+Date: Tue, 2 Mar 2021 17:47:02 +0100
+Subject: [PATCH] ALSA: virtio: add virtio sound driver
+
+Introduce skeleton of the virtio sound driver. The driver implements
+the virtio sound device specification, which has become part of the
+virtio standard.
+
+Initial initialization of the device, virtqueues and creation of an
+empty ALSA sound device.
+
+Signed-off-by: Anton Yakovlev <anton.yakovlev@opensynergy.com>
+Link: https://lore.kernel.org/r/20210302164709.3142702-3-anton.yakovlev@opensynergy.com
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+Signed-off-by: Vasyl Vavrychuk <vasyl.vavrychuk@opensynergy.com>
+---
+ MAINTAINERS | 9 +
+ include/uapi/linux/virtio_snd.h | 334 ++++++++++++++++++++++++++++++++
+ sound/Kconfig | 2 +
+ sound/Makefile | 3 +-
+ sound/virtio/Kconfig | 10 +
+ sound/virtio/Makefile | 7 +
+ sound/virtio/virtio_card.c | 324 +++++++++++++++++++++++++++++++
+ sound/virtio/virtio_card.h | 65 +++++++
+ 8 files changed, 753 insertions(+), 1 deletion(-)
+ create mode 100644 include/uapi/linux/virtio_snd.h
+ create mode 100644 sound/virtio/Kconfig
+ create mode 100644 sound/virtio/Makefile
+ create mode 100644 sound/virtio/virtio_card.c
+ create mode 100644 sound/virtio/virtio_card.h
+
+diff --git a/MAINTAINERS b/MAINTAINERS
+index 407ae5c24566..49772b741967 100644
+--- a/MAINTAINERS
++++ b/MAINTAINERS
+@@ -18670,6 +18670,15 @@ W: https://virtio-mem.gitlab.io/
+ F: drivers/virtio/virtio_mem.c
+ F: include/uapi/linux/virtio_mem.h
+
++VIRTIO SOUND DRIVER
++M: Anton Yakovlev <anton.yakovlev@opensynergy.com>
++M: "Michael S. Tsirkin" <mst@redhat.com>
++L: virtualization@lists.linux-foundation.org
++L: alsa-devel@alsa-project.org (moderated for non-subscribers)
++S: Maintained
++F: include/uapi/linux/virtio_snd.h
++F: sound/virtio/*
++
+ VIRTUAL BOX GUEST DEVICE DRIVER
+ M: Hans de Goede <hdegoede@redhat.com>
+ M: Arnd Bergmann <arnd@arndb.de>
+diff --git a/include/uapi/linux/virtio_snd.h b/include/uapi/linux/virtio_snd.h
+new file mode 100644
+index 000000000000..dfe49547a7b0
+--- /dev/null
++++ b/include/uapi/linux/virtio_snd.h
+@@ -0,0 +1,334 @@
++/* SPDX-License-Identifier: BSD-3-Clause */
++/*
++ * Copyright (C) 2021 OpenSynergy GmbH
++ */
++#ifndef VIRTIO_SND_IF_H
++#define VIRTIO_SND_IF_H
++
++#include <linux/virtio_types.h>
++
++/*******************************************************************************
++ * CONFIGURATION SPACE
++ */
++struct virtio_snd_config {
++ /* # of available physical jacks */
++ __le32 jacks;
++ /* # of available PCM streams */
++ __le32 streams;
++ /* # of available channel maps */
++ __le32 chmaps;
++};
++
++enum {
++ /* device virtqueue indexes */
++ VIRTIO_SND_VQ_CONTROL = 0,
++ VIRTIO_SND_VQ_EVENT,
++ VIRTIO_SND_VQ_TX,
++ VIRTIO_SND_VQ_RX,
++ /* # of device virtqueues */
++ VIRTIO_SND_VQ_MAX
++};
++
++/*******************************************************************************
++ * COMMON DEFINITIONS
++ */
++
++/* supported dataflow directions */
++enum {
++ VIRTIO_SND_D_OUTPUT = 0,
++ VIRTIO_SND_D_INPUT
++};
++
++enum {
++ /* jack control request types */
++ VIRTIO_SND_R_JACK_INFO = 1,
++ VIRTIO_SND_R_JACK_REMAP,
++
++ /* PCM control request types */
++ VIRTIO_SND_R_PCM_INFO = 0x0100,
++ VIRTIO_SND_R_PCM_SET_PARAMS,
++ VIRTIO_SND_R_PCM_PREPARE,
++ VIRTIO_SND_R_PCM_RELEASE,
++ VIRTIO_SND_R_PCM_START,
++ VIRTIO_SND_R_PCM_STOP,
++
++ /* channel map control request types */
++ VIRTIO_SND_R_CHMAP_INFO = 0x0200,
++
++ /* jack event types */
++ VIRTIO_SND_EVT_JACK_CONNECTED = 0x1000,
++ VIRTIO_SND_EVT_JACK_DISCONNECTED,
++
++ /* PCM event types */
++ VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED = 0x1100,
++ VIRTIO_SND_EVT_PCM_XRUN,
++
++ /* common status codes */
++ VIRTIO_SND_S_OK = 0x8000,
++ VIRTIO_SND_S_BAD_MSG,
++ VIRTIO_SND_S_NOT_SUPP,
++ VIRTIO_SND_S_IO_ERR
++};
++
++/* common header */
++struct virtio_snd_hdr {
++ __le32 code;
++};
++
++/* event notification */
++struct virtio_snd_event {
++ /* VIRTIO_SND_EVT_XXX */
++ struct virtio_snd_hdr hdr;
++ /* optional event data */
++ __le32 data;
++};
++
++/* common control request to query an item information */
++struct virtio_snd_query_info {
++ /* VIRTIO_SND_R_XXX_INFO */
++ struct virtio_snd_hdr hdr;
++ /* item start identifier */
++ __le32 start_id;
++ /* item count to query */
++ __le32 count;
++ /* item information size in bytes */
++ __le32 size;
++};
++
++/* common item information header */
++struct virtio_snd_info {
++ /* function group node id (High Definition Audio Specification 7.1.2) */
++ __le32 hda_fn_nid;
++};
++
++/*******************************************************************************
++ * JACK CONTROL MESSAGES
++ */
++struct virtio_snd_jack_hdr {
++ /* VIRTIO_SND_R_JACK_XXX */
++ struct virtio_snd_hdr hdr;
++ /* 0 ... virtio_snd_config::jacks - 1 */
++ __le32 jack_id;
++};
++
++/* supported jack features */
++enum {
++ VIRTIO_SND_JACK_F_REMAP = 0
++};
++
++struct virtio_snd_jack_info {
++ /* common header */
++ struct virtio_snd_info hdr;
++ /* supported feature bit map (1 << VIRTIO_SND_JACK_F_XXX) */
++ __le32 features;
++ /* pin configuration (High Definition Audio Specification 7.3.3.31) */
++ __le32 hda_reg_defconf;
++ /* pin capabilities (High Definition Audio Specification 7.3.4.9) */
++ __le32 hda_reg_caps;
++ /* current jack connection status (0: disconnected, 1: connected) */
++ __u8 connected;
++
++ __u8 padding[7];
++};
++
++/* jack remapping control request */
++struct virtio_snd_jack_remap {
++ /* .code = VIRTIO_SND_R_JACK_REMAP */
++ struct virtio_snd_jack_hdr hdr;
++ /* selected association number */
++ __le32 association;
++ /* selected sequence number */
++ __le32 sequence;
++};
++
++/*******************************************************************************
++ * PCM CONTROL MESSAGES
++ */
++struct virtio_snd_pcm_hdr {
++ /* VIRTIO_SND_R_PCM_XXX */
++ struct virtio_snd_hdr hdr;
++ /* 0 ... virtio_snd_config::streams - 1 */
++ __le32 stream_id;
++};
++
++/* supported PCM stream features */
++enum {
++ VIRTIO_SND_PCM_F_SHMEM_HOST = 0,
++ VIRTIO_SND_PCM_F_SHMEM_GUEST,
++ VIRTIO_SND_PCM_F_MSG_POLLING,
++ VIRTIO_SND_PCM_F_EVT_SHMEM_PERIODS,
++ VIRTIO_SND_PCM_F_EVT_XRUNS
++};
++
++/* supported PCM sample formats */
++enum {
++ /* analog formats (width / physical width) */
++ VIRTIO_SND_PCM_FMT_IMA_ADPCM = 0, /* 4 / 4 bits */
++ VIRTIO_SND_PCM_FMT_MU_LAW, /* 8 / 8 bits */
++ VIRTIO_SND_PCM_FMT_A_LAW, /* 8 / 8 bits */
++ VIRTIO_SND_PCM_FMT_S8, /* 8 / 8 bits */
++ VIRTIO_SND_PCM_FMT_U8, /* 8 / 8 bits */
++ VIRTIO_SND_PCM_FMT_S16, /* 16 / 16 bits */
++ VIRTIO_SND_PCM_FMT_U16, /* 16 / 16 bits */
++ VIRTIO_SND_PCM_FMT_S18_3, /* 18 / 24 bits */
++ VIRTIO_SND_PCM_FMT_U18_3, /* 18 / 24 bits */
++ VIRTIO_SND_PCM_FMT_S20_3, /* 20 / 24 bits */
++ VIRTIO_SND_PCM_FMT_U20_3, /* 20 / 24 bits */
++ VIRTIO_SND_PCM_FMT_S24_3, /* 24 / 24 bits */
++ VIRTIO_SND_PCM_FMT_U24_3, /* 24 / 24 bits */
++ VIRTIO_SND_PCM_FMT_S20, /* 20 / 32 bits */
++ VIRTIO_SND_PCM_FMT_U20, /* 20 / 32 bits */
++ VIRTIO_SND_PCM_FMT_S24, /* 24 / 32 bits */
++ VIRTIO_SND_PCM_FMT_U24, /* 24 / 32 bits */
++ VIRTIO_SND_PCM_FMT_S32, /* 32 / 32 bits */
++ VIRTIO_SND_PCM_FMT_U32, /* 32 / 32 bits */
++ VIRTIO_SND_PCM_FMT_FLOAT, /* 32 / 32 bits */
++ VIRTIO_SND_PCM_FMT_FLOAT64, /* 64 / 64 bits */
++ /* digital formats (width / physical width) */
++ VIRTIO_SND_PCM_FMT_DSD_U8, /* 8 / 8 bits */
++ VIRTIO_SND_PCM_FMT_DSD_U16, /* 16 / 16 bits */
++ VIRTIO_SND_PCM_FMT_DSD_U32, /* 32 / 32 bits */
++ VIRTIO_SND_PCM_FMT_IEC958_SUBFRAME /* 32 / 32 bits */
++};
++
++/* supported PCM frame rates */
++enum {
++ VIRTIO_SND_PCM_RATE_5512 = 0,
++ VIRTIO_SND_PCM_RATE_8000,
++ VIRTIO_SND_PCM_RATE_11025,
++ VIRTIO_SND_PCM_RATE_16000,
++ VIRTIO_SND_PCM_RATE_22050,
++ VIRTIO_SND_PCM_RATE_32000,
++ VIRTIO_SND_PCM_RATE_44100,
++ VIRTIO_SND_PCM_RATE_48000,
++ VIRTIO_SND_PCM_RATE_64000,
++ VIRTIO_SND_PCM_RATE_88200,
++ VIRTIO_SND_PCM_RATE_96000,
++ VIRTIO_SND_PCM_RATE_176400,
++ VIRTIO_SND_PCM_RATE_192000,
++ VIRTIO_SND_PCM_RATE_384000
++};
++
++struct virtio_snd_pcm_info {
++ /* common header */
++ struct virtio_snd_info hdr;
++ /* supported feature bit map (1 << VIRTIO_SND_PCM_F_XXX) */
++ __le32 features;
++ /* supported sample format bit map (1 << VIRTIO_SND_PCM_FMT_XXX) */
++ __le64 formats;
++ /* supported frame rate bit map (1 << VIRTIO_SND_PCM_RATE_XXX) */
++ __le64 rates;
++ /* dataflow direction (VIRTIO_SND_D_XXX) */
++ __u8 direction;
++ /* minimum # of supported channels */
++ __u8 channels_min;
++ /* maximum # of supported channels */
++ __u8 channels_max;
++
++ __u8 padding[5];
++};
++
++/* set PCM stream format */
++struct virtio_snd_pcm_set_params {
++ /* .code = VIRTIO_SND_R_PCM_SET_PARAMS */
++ struct virtio_snd_pcm_hdr hdr;
++ /* size of the hardware buffer */
++ __le32 buffer_bytes;
++ /* size of the hardware period */
++ __le32 period_bytes;
++ /* selected feature bit map (1 << VIRTIO_SND_PCM_F_XXX) */
++ __le32 features;
++ /* selected # of channels */
++ __u8 channels;
++ /* selected sample format (VIRTIO_SND_PCM_FMT_XXX) */
++ __u8 format;
++ /* selected frame rate (VIRTIO_SND_PCM_RATE_XXX) */
++ __u8 rate;
++
++ __u8 padding;
++};
++
++/*******************************************************************************
++ * PCM I/O MESSAGES
++ */
++
++/* I/O request header */
++struct virtio_snd_pcm_xfer {
++ /* 0 ... virtio_snd_config::streams - 1 */
++ __le32 stream_id;
++};
++
++/* I/O request status */
++struct virtio_snd_pcm_status {
++ /* VIRTIO_SND_S_XXX */
++ __le32 status;
++ /* current device latency */
++ __le32 latency_bytes;
++};
++
++/*******************************************************************************
++ * CHANNEL MAP CONTROL MESSAGES
++ */
++struct virtio_snd_chmap_hdr {
++ /* VIRTIO_SND_R_CHMAP_XXX */
++ struct virtio_snd_hdr hdr;
++ /* 0 ... virtio_snd_config::chmaps - 1 */
++ __le32 chmap_id;
++};
++
++/* standard channel position definition */
++enum {
++ VIRTIO_SND_CHMAP_NONE = 0, /* undefined */
++ VIRTIO_SND_CHMAP_NA, /* silent */
++ VIRTIO_SND_CHMAP_MONO, /* mono stream */
++ VIRTIO_SND_CHMAP_FL, /* front left */
++ VIRTIO_SND_CHMAP_FR, /* front right */
++ VIRTIO_SND_CHMAP_RL, /* rear left */
++ VIRTIO_SND_CHMAP_RR, /* rear right */
++ VIRTIO_SND_CHMAP_FC, /* front center */
++ VIRTIO_SND_CHMAP_LFE, /* low frequency (LFE) */
++ VIRTIO_SND_CHMAP_SL, /* side left */
++ VIRTIO_SND_CHMAP_SR, /* side right */
++ VIRTIO_SND_CHMAP_RC, /* rear center */
++ VIRTIO_SND_CHMAP_FLC, /* front left center */
++ VIRTIO_SND_CHMAP_FRC, /* front right center */
++ VIRTIO_SND_CHMAP_RLC, /* rear left center */
++ VIRTIO_SND_CHMAP_RRC, /* rear right center */
++ VIRTIO_SND_CHMAP_FLW, /* front left wide */
++ VIRTIO_SND_CHMAP_FRW, /* front right wide */
++ VIRTIO_SND_CHMAP_FLH, /* front left high */
++ VIRTIO_SND_CHMAP_FCH, /* front center high */
++ VIRTIO_SND_CHMAP_FRH, /* front right high */
++ VIRTIO_SND_CHMAP_TC, /* top center */
++ VIRTIO_SND_CHMAP_TFL, /* top front left */
++ VIRTIO_SND_CHMAP_TFR, /* top front right */
++ VIRTIO_SND_CHMAP_TFC, /* top front center */
++ VIRTIO_SND_CHMAP_TRL, /* top rear left */
++ VIRTIO_SND_CHMAP_TRR, /* top rear right */
++ VIRTIO_SND_CHMAP_TRC, /* top rear center */
++ VIRTIO_SND_CHMAP_TFLC, /* top front left center */
++ VIRTIO_SND_CHMAP_TFRC, /* top front right center */
++ VIRTIO_SND_CHMAP_TSL, /* top side left */
++ VIRTIO_SND_CHMAP_TSR, /* top side right */
++ VIRTIO_SND_CHMAP_LLFE, /* left LFE */
++ VIRTIO_SND_CHMAP_RLFE, /* right LFE */
++ VIRTIO_SND_CHMAP_BC, /* bottom center */
++ VIRTIO_SND_CHMAP_BLC, /* bottom left center */
++ VIRTIO_SND_CHMAP_BRC /* bottom right center */
++};
++
++/* maximum possible number of channels */
++#define VIRTIO_SND_CHMAP_MAX_SIZE 18
++
++struct virtio_snd_chmap_info {
++ /* common header */
++ struct virtio_snd_info hdr;
++ /* dataflow direction (VIRTIO_SND_D_XXX) */
++ __u8 direction;
++ /* # of valid channel position values */
++ __u8 channels;
++ /* channel position values (VIRTIO_SND_CHMAP_XXX) */
++ __u8 positions[VIRTIO_SND_CHMAP_MAX_SIZE];
++};
++
++#endif /* VIRTIO_SND_IF_H */
+diff --git a/sound/Kconfig b/sound/Kconfig
+index 36785410fbe1..e56d96d2b11c 100644
+--- a/sound/Kconfig
++++ b/sound/Kconfig
+@@ -99,6 +99,8 @@ source "sound/synth/Kconfig"
+
+ source "sound/xen/Kconfig"
+
++source "sound/virtio/Kconfig"
++
+ endif # SND
+
+ endif # !UML
+diff --git a/sound/Makefile b/sound/Makefile
+index 797ecdcd35e2..04ef04b1168f 100644
+--- a/sound/Makefile
++++ b/sound/Makefile
+@@ -5,7 +5,8 @@
+ obj-$(CONFIG_SOUND) += soundcore.o
+ obj-$(CONFIG_DMASOUND) += oss/dmasound/
+ obj-$(CONFIG_SND) += core/ i2c/ drivers/ isa/ pci/ ppc/ arm/ sh/ synth/ usb/ \
+- firewire/ sparc/ spi/ parisc/ pcmcia/ mips/ soc/ atmel/ hda/ x86/ xen/
++ firewire/ sparc/ spi/ parisc/ pcmcia/ mips/ soc/ atmel/ hda/ x86/ xen/ \
++ virtio/
+ obj-$(CONFIG_SND_AOA) += aoa/
+
+ # This one must be compilable even if sound is configured out
+diff --git a/sound/virtio/Kconfig b/sound/virtio/Kconfig
+new file mode 100644
+index 000000000000..094cba24ee5b
+--- /dev/null
++++ b/sound/virtio/Kconfig
+@@ -0,0 +1,10 @@
++# SPDX-License-Identifier: GPL-2.0+
++# Sound card driver for virtio
++
++config SND_VIRTIO
++ tristate "Virtio sound driver"
++ depends on VIRTIO
++ select SND_PCM
++ select SND_JACK
++ help
++ This is the virtual sound driver for virtio. Say Y or M.
+diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile
+new file mode 100644
+index 000000000000..8c87ebb9982b
+--- /dev/null
++++ b/sound/virtio/Makefile
+@@ -0,0 +1,7 @@
++# SPDX-License-Identifier: GPL-2.0+
++
++obj-$(CONFIG_SND_VIRTIO) += virtio_snd.o
++
++virtio_snd-objs := \
++ virtio_card.o
++
+diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c
+new file mode 100644
+index 000000000000..5a37056858e9
+--- /dev/null
++++ b/sound/virtio/virtio_card.c
+@@ -0,0 +1,324 @@
++// SPDX-License-Identifier: GPL-2.0+
++/*
++ * virtio-snd: Virtio sound device
++ * Copyright (C) 2021 OpenSynergy GmbH
++ */
++#include <linux/module.h>
++#include <linux/moduleparam.h>
++#include <linux/virtio_config.h>
++#include <sound/initval.h>
++#include <uapi/linux/virtio_ids.h>
++
++#include "virtio_card.h"
++
++static void virtsnd_remove(struct virtio_device *vdev);
++
++/**
++ * virtsnd_event_send() - Add an event to the event queue.
++ * @vqueue: Underlying event virtqueue.
++ * @event: Event.
++ * @notify: Indicates whether or not to send a notification to the device.
++ * @gfp: Kernel flags for memory allocation.
++ *
++ * Context: Any context.
++ */
++static void virtsnd_event_send(struct virtqueue *vqueue,
++ struct virtio_snd_event *event, bool notify,
++ gfp_t gfp)
++{
++ struct scatterlist sg;
++ struct scatterlist *psgs[1] = { &sg };
++
++ /* reset event content */
++ memset(event, 0, sizeof(*event));
++
++ sg_init_one(&sg, event, sizeof(*event));
++
++ if (virtqueue_add_sgs(vqueue, psgs, 0, 1, event, gfp) || !notify)
++ return;
++
++ if (virtqueue_kick_prepare(vqueue))
++ virtqueue_notify(vqueue);
++}
++
++/**
++ * virtsnd_event_dispatch() - Dispatch an event from the device side.
++ * @snd: VirtIO sound device.
++ * @event: VirtIO sound event.
++ *
++ * Context: Any context.
++ */
++static void virtsnd_event_dispatch(struct virtio_snd *snd,
++ struct virtio_snd_event *event)
++{
++}
++
++/**
++ * virtsnd_event_notify_cb() - Dispatch all reported events from the event queue.
++ * @vqueue: Underlying event virtqueue.
++ *
++ * This callback function is called upon a vring interrupt request from the
++ * device.
++ *
++ * Context: Interrupt context.
++ */
++static void virtsnd_event_notify_cb(struct virtqueue *vqueue)
++{
++ struct virtio_snd *snd = vqueue->vdev->priv;
++ struct virtio_snd_queue *queue = virtsnd_event_queue(snd);
++ struct virtio_snd_event *event;
++ u32 length;
++ unsigned long flags;
++
++ spin_lock_irqsave(&queue->lock, flags);
++ do {
++ virtqueue_disable_cb(vqueue);
++ while ((event = virtqueue_get_buf(vqueue, &length))) {
++ virtsnd_event_dispatch(snd, event);
++ virtsnd_event_send(vqueue, event, true, GFP_ATOMIC);
++ }
++ if (unlikely(virtqueue_is_broken(vqueue)))
++ break;
++ } while (!virtqueue_enable_cb(vqueue));
++ spin_unlock_irqrestore(&queue->lock, flags);
++}
++
++/**
++ * virtsnd_find_vqs() - Enumerate and initialize all virtqueues.
++ * @snd: VirtIO sound device.
++ *
++ * After calling this function, the event queue is disabled.
++ *
++ * Context: Any context.
++ * Return: 0 on success, -errno on failure.
++ */
++static int virtsnd_find_vqs(struct virtio_snd *snd)
++{
++ struct virtio_device *vdev = snd->vdev;
++ static vq_callback_t *callbacks[VIRTIO_SND_VQ_MAX] = {
++ [VIRTIO_SND_VQ_EVENT] = virtsnd_event_notify_cb
++ };
++ static const char *names[VIRTIO_SND_VQ_MAX] = {
++ [VIRTIO_SND_VQ_EVENT] = "virtsnd-event"
++ };
++ struct virtqueue *vqs[VIRTIO_SND_VQ_MAX] = { 0 };
++ unsigned int i;
++ unsigned int n;
++ int rc;
++
++ rc = virtio_find_vqs(vdev, VIRTIO_SND_VQ_MAX, vqs, callbacks, names,
++ NULL);
++ if (rc) {
++ dev_err(&vdev->dev, "failed to initialize virtqueues\n");
++ return rc;
++ }
++
++ for (i = 0; i < VIRTIO_SND_VQ_MAX; ++i)
++ snd->queues[i].vqueue = vqs[i];
++
++ /* Allocate events and populate the event queue */
++ virtqueue_disable_cb(vqs[VIRTIO_SND_VQ_EVENT]);
++
++ n = virtqueue_get_vring_size(vqs[VIRTIO_SND_VQ_EVENT]);
++
++ snd->event_msgs = kmalloc_array(n, sizeof(*snd->event_msgs),
++ GFP_KERNEL);
++ if (!snd->event_msgs)
++ return -ENOMEM;
++
++ for (i = 0; i < n; ++i)
++ virtsnd_event_send(vqs[VIRTIO_SND_VQ_EVENT],
++ &snd->event_msgs[i], false, GFP_KERNEL);
++
++ return 0;
++}
++
++/**
++ * virtsnd_enable_event_vq() - Enable the event virtqueue.
++ * @snd: VirtIO sound device.
++ *
++ * Context: Any context.
++ */
++static void virtsnd_enable_event_vq(struct virtio_snd *snd)
++{
++ struct virtio_snd_queue *queue = virtsnd_event_queue(snd);
++
++ if (!virtqueue_enable_cb(queue->vqueue))
++ virtsnd_event_notify_cb(queue->vqueue);
++}
++
++/**
++ * virtsnd_disable_event_vq() - Disable the event virtqueue.
++ * @snd: VirtIO sound device.
++ *
++ * Context: Any context.
++ */
++static void virtsnd_disable_event_vq(struct virtio_snd *snd)
++{
++ struct virtio_snd_queue *queue = virtsnd_event_queue(snd);
++ struct virtio_snd_event *event;
++ u32 length;
++ unsigned long flags;
++
++ if (queue->vqueue) {
++ spin_lock_irqsave(&queue->lock, flags);
++ virtqueue_disable_cb(queue->vqueue);
++ while ((event = virtqueue_get_buf(queue->vqueue, &length)))
++ virtsnd_event_dispatch(snd, event);
++ spin_unlock_irqrestore(&queue->lock, flags);
++ }
++}
++
++/**
++ * virtsnd_build_devs() - Read configuration and build ALSA devices.
++ * @snd: VirtIO sound device.
++ *
++ * Context: Any context that permits to sleep.
++ * Return: 0 on success, -errno on failure.
++ */
++static int virtsnd_build_devs(struct virtio_snd *snd)
++{
++ struct virtio_device *vdev = snd->vdev;
++ struct device *dev = &vdev->dev;
++ int rc;
++
++ rc = snd_card_new(dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
++ THIS_MODULE, 0, &snd->card);
++ if (rc < 0)
++ return rc;
++
++ snd->card->private_data = snd;
++
++ strscpy(snd->card->driver, VIRTIO_SND_CARD_DRIVER,
++ sizeof(snd->card->driver));
++ strscpy(snd->card->shortname, VIRTIO_SND_CARD_NAME,
++ sizeof(snd->card->shortname));
++ if (dev->parent->bus)
++ snprintf(snd->card->longname, sizeof(snd->card->longname),
++ VIRTIO_SND_CARD_NAME " at %s/%s/%s",
++ dev->parent->bus->name, dev_name(dev->parent),
++ dev_name(dev));
++ else
++ snprintf(snd->card->longname, sizeof(snd->card->longname),
++ VIRTIO_SND_CARD_NAME " at %s/%s",
++ dev_name(dev->parent), dev_name(dev));
++
++ return snd_card_register(snd->card);
++}
++
++/**
++ * virtsnd_validate() - Validate if the device can be started.
++ * @vdev: VirtIO parent device.
++ *
++ * Context: Any context.
++ * Return: 0 on success, -EINVAL on failure.
++ */
++static int virtsnd_validate(struct virtio_device *vdev)
++{
++ if (!vdev->config->get) {
++ dev_err(&vdev->dev, "configuration access disabled\n");
++ return -EINVAL;
++ }
++
++ if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
++ dev_err(&vdev->dev,
++ "device does not comply with spec version 1.x\n");
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++/**
++ * virtsnd_probe() - Create and initialize the device.
++ * @vdev: VirtIO parent device.
++ *
++ * Context: Any context that permits to sleep.
++ * Return: 0 on success, -errno on failure.
++ */
++static int virtsnd_probe(struct virtio_device *vdev)
++{
++ struct virtio_snd *snd;
++ unsigned int i;
++ int rc;
++
++ snd = devm_kzalloc(&vdev->dev, sizeof(*snd), GFP_KERNEL);
++ if (!snd)
++ return -ENOMEM;
++
++ snd->vdev = vdev;
++
++ vdev->priv = snd;
++
++ for (i = 0; i < VIRTIO_SND_VQ_MAX; ++i)
++ spin_lock_init(&snd->queues[i].lock);
++
++ rc = virtsnd_find_vqs(snd);
++ if (rc)
++ goto on_exit;
++
++ virtio_device_ready(vdev);
++
++ rc = virtsnd_build_devs(snd);
++ if (rc)
++ goto on_exit;
++
++ virtsnd_enable_event_vq(snd);
++
++on_exit:
++ if (rc)
++ virtsnd_remove(vdev);
++
++ return rc;
++}
++
++/**
++ * virtsnd_remove() - Remove VirtIO and ALSA devices.
++ * @vdev: VirtIO parent device.
++ *
++ * Context: Any context that permits to sleep.
++ */
++static void virtsnd_remove(struct virtio_device *vdev)
++{
++ struct virtio_snd *snd = vdev->priv;
++
++ virtsnd_disable_event_vq(snd);
++
++ if (snd->card)
++ snd_card_free(snd->card);
++
++ vdev->config->del_vqs(vdev);
++ vdev->config->reset(vdev);
++
++ kfree(snd->event_msgs);
++}
++
++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,
++};
++
++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..b903b1b12e90
+--- /dev/null
++++ b/sound/virtio/virtio_card.h
+@@ -0,0 +1,65 @@
++/* SPDX-License-Identifier: GPL-2.0+ */
++/*
++ * virtio-snd: Virtio sound device
++ * Copyright (C) 2021 OpenSynergy GmbH
++ */
++#ifndef VIRTIO_SND_CARD_H
++#define VIRTIO_SND_CARD_H
++
++#include <linux/slab.h>
++#include <linux/virtio.h>
++#include <sound/core.h>
++#include <uapi/linux/virtio_snd.h>
++
++#define VIRTIO_SND_CARD_DRIVER "virtio-snd"
++#define VIRTIO_SND_CARD_NAME "VirtIO SoundCard"
++
++/**
++ * struct virtio_snd_queue - Virtqueue wrapper structure.
++ * @lock: Used to synchronize access to a virtqueue.
++ * @vqueue: Underlying virtqueue.
++ */
++struct virtio_snd_queue {
++ spinlock_t lock;
++ struct virtqueue *vqueue;
++};
++
++/**
++ * struct virtio_snd - VirtIO sound card device.
++ * @vdev: Underlying virtio device.
++ * @queues: Virtqueue wrappers.
++ * @card: ALSA sound card.
++ * @event_msgs: Device events.
++ */
++struct virtio_snd {
++ struct virtio_device *vdev;
++ struct virtio_snd_queue queues[VIRTIO_SND_VQ_MAX];
++ struct snd_card *card;
++ struct virtio_snd_event *event_msgs;
++};
++
++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 */