// SPDX-License-Identifier: GPL-2.0+
/*
* virtio-snd: Virtio sound device
* Copyright (C) 2022 OpenSynergy GmbH
*/
#include <sound/control.h>
#include <linux/virtio_config.h>
#include "virtio_card.h"
/* Map for converting VirtIO types to ALSA types. */
static const snd_ctl_elem_type_t g_v2a_type_map[] = {
[VIRTIO_SND_CTL_TYPE_BOOLEAN] = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
[VIRTIO_SND_CTL_TYPE_INTEGER] = SNDRV_CTL_ELEM_TYPE_INTEGER,
[VIRTIO_SND_CTL_TYPE_INTEGER64] = SNDRV_CTL_ELEM_TYPE_INTEGER64,
[VIRTIO_SND_CTL_TYPE_ENUMERATED] = SNDRV_CTL_ELEM_TYPE_ENUMERATED,
[VIRTIO_SND_CTL_TYPE_BYTES] = SNDRV_CTL_ELEM_TYPE_BYTES,
[VIRTIO_SND_CTL_TYPE_IEC958] = SNDRV_CTL_ELEM_TYPE_IEC958
};
/* Map for converting VirtIO access rights to ALSA access rights. */
static const unsigned int g_v2a_access_map[] = {
[VIRTIO_SND_CTL_ACCESS_READ] = SNDRV_CTL_ELEM_ACCESS_READ,
[VIRTIO_SND_CTL_ACCESS_WRITE] = SNDRV_CTL_ELEM_ACCESS_WRITE,
[VIRTIO_SND_CTL_ACCESS_VOLATILE] = SNDRV_CTL_ELEM_ACCESS_VOLATILE,
[VIRTIO_SND_CTL_ACCESS_INACTIVE] = SNDRV_CTL_ELEM_ACCESS_INACTIVE,
[VIRTIO_SND_CTL_ACCESS_TLV_READ] = SNDRV_CTL_ELEM_ACCESS_TLV_READ,
[VIRTIO_SND_CTL_ACCESS_TLV_WRITE] = SNDRV_CTL_ELEM_ACCESS_TLV_WRITE,
[VIRTIO_SND_CTL_ACCESS_TLV_COMMAND] = SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND
};
/* Map for converting VirtIO event masks to ALSA event masks. */
static const unsigned int g_v2a_mask_map[] = {
[VIRTIO_SND_CTL_EVT_MASK_VALUE] = SNDRV_CTL_EVENT_MASK_VALUE,
[VIRTIO_SND_CTL_EVT_MASK_INFO] = SNDRV_CTL_EVENT_MASK_INFO,
[VIRTIO_SND_CTL_EVT_MASK_TLV] = SNDRV_CTL_EVENT_MASK_TLV
};
/**
* virtsnd_kctl_info() - Returns information about the control.
* @kcontrol: ALSA control element.
* @uinfo: Element information.
*
* Context: Process context.
* Return: 0 on success, -errno on failure.
*/
static int virtsnd_kctl_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo)
{
struct virtio_snd *snd = kcontrol->private_data;
struct virtio_kctl *kctl = &snd->kctls[kcontrol->private_value];
struct virtio_snd_ctl_info *kinfo =
&snd->kctl_infos[kcontrol->private_value];
unsigned int i;
uinfo->type = g_v2a_type_map[le32_to_cpu(kinfo->type)];
uinfo->count = le32_to_cpu(kinfo->count);
switch (uinfo->type) {
case SNDRV_CTL_ELEM_TYPE_INTEGER:
uinfo->value.integer.min =
le32_to_cpu(kinfo->value.integer.min);
uinfo->value.integer.max =
le32_to_cpu(kinfo->value.integer.max);
uinfo->value.integer.step =
le32_to_cpu(kinfo->value.integer.step);
break;
case SNDRV_CTL_ELEM_TYPE_INTEGER64:
uinfo->value.integer64.min =
le64_to_cpu(kinfo->value.integer64.min);
uinfo->value.integer64.max =
le64_to_cpu(kinfo->value.integer64.max);
uinfo->value.integer64.step =
le64_to_cpu(kinfo->value.integer64.step);
break;
case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
uinfo->value.enumerated.items =
le32_to_cpu(kinfo->value.enumerated.items);
i = uinfo->value.enumerated.item;
if (i >= uinfo->value.enumerated.items)
return -EINVAL;
strscpy(uinfo->value.enumerated.name, kctl->items[i].item,
sizeof(uinfo->value.enumerated.name));
break;
}
return 0;
}
/**
* virtsnd_kctl_get() - Read the value from the control.
* @kcontrol: ALSA control element.
* @uvalue: Element value.
*
* Context: Process context.
* Return: 0 on success, -errno on failure.
*/
static int virtsnd_kctl_get(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *uvalue)
{
struct virtio_snd *snd = kcontrol->private_data;
struct virtio_snd_ctl_info *kinfo =
&snd->kctl_infos[kcontrol->private_value];
unsigned int type = le32_to_cpu(kinfo->type);
unsigned int count = le32_to_cpu(kinfo->count);
struct virtio_snd_msg *msg;
struct virtio_snd_ctl_hdr *hdr;
struct virtio_snd_ctl_value *kvalue;
size_t request_size = sizeof(*hdr);
size_t response_size = sizeof(struct virtio_snd_hdr) + sizeof(*kvalue);
unsigned int i;
int rc;
msg = virtsnd_ctl_msg_alloc(request_size, response_size, GFP_KERNEL);
if (!msg)
return -ENOMEM;
virtsnd_ctl_msg_ref(msg);
hdr = virtsnd_ctl_msg_request(msg);
hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_READ);
hdr->control_id = cpu_to_le32(kcontrol->private_value);
rc = virtsnd_ctl_msg_send_sync(snd, msg);
if (rc)
goto on_failure;
kvalue = (void *)((u8 *)virtsnd_ctl_msg_response(msg) +
sizeof(struct virtio_snd_hdr));
switch (type) {
case VIRTIO_SND_CTL_TYPE_BOOLEAN:
case VIRTIO_SND_CTL_TYPE_INTEGER:
for (i = 0; i < count; ++i)
uvalue->value.integer.value[i] =
le32_to_cpu(kvalue->value.integer[i]);
break;
case VIRTIO_SND_CTL_TYPE_INTEGER64:
for (i = 0; i < count; ++i)
uvalue->value.integer64.value[i] =
le64_to_cpu(kvalue->value.integer64[i]);
break;
case VIRTIO_SND_CTL_TYPE_ENUMERATED:
for (i = 0; i < count; ++i)
uvalue->value.enumerated.item[i] =
le32_to_cpu(kvalue->value.enumerated[i]);
break;
case VIRTIO_SND_CTL_TYPE_BYTES:
memcpy(uvalue->value.bytes.data, kvalue->value.bytes, count);
break;
case VIRTIO_SND_CTL_TYPE_IEC958:
memcpy(&uvalue->value.iec958, &kvalue->value.iec958,
sizeof(uvalue->value.iec958));
break;
}
on_failure:
virtsnd_ctl_msg_unref(msg);
return rc;
}
/**
* virtsnd_kctl_put() - Write the value to the control.
* @kcontrol: ALSA control element.
* @uvalue: Element value.
*
* Context: Process context.
* Return: 0 on success, -errno on failure.
*/
static int virtsnd_kctl_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *uvalue)
{
struct virtio_snd *snd = kcontrol->private_data;
struct virtio_snd_ctl_info *kinfo =
&snd->kctl_infos[kcontrol->private_value];
unsigned int type = le32_to_cpu(kinfo->type);
unsigned int count = le32_to_cpu(kinfo->count);
struct virtio_snd_msg *msg;
struct virtio_snd_ctl_hdr *hdr;
struct virtio_snd_ctl_value *kvalue;
size_t request_size = sizeof(*hdr) + sizeof(*kvalue);
size_t response_size = sizeof(struct virtio_snd_hdr);
unsigned int i;
msg = virtsnd_ctl_msg_alloc(request_size, response_size, GFP_KERNEL);
if (!msg)
return -ENOMEM;
hdr = virtsnd_ctl_msg_request(msg);
hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_WRITE);
hdr->control_id = cpu_to_le32(kcontrol->private_value);
kvalue = (void *)((u8 *)hdr + sizeof(*hdr));
switch (type) {
case VIRTIO_SND_CTL_TYPE_BOOLEAN:
case VIRTIO_SND_CTL_TYPE_INTEGER:
for (i = 0; i < count; ++i)
kvalue->value.integer[i] =
cpu_to_le32(uvalue->value.integer.value[i]);
break;
case VIRTIO_SND_CTL_TYPE_INTEGER64:
for (i = 0; i < count; ++i)
kvalue->value.integer64[i] =
cpu_to_le64(uvalue->value.integer64.value[i]);
break;
case VIRTIO_SND_CTL_TYPE_ENUMERATED:
for (i = 0; i < count; ++i)
kvalue->value.enumerated[i] =
cpu_to_le32(uvalue->value.enumerated.item[i]);
break;
case VIRTIO_SND_CTL_TYPE_BYTES:
memcpy(kvalue->value.bytes, uvalue->value.bytes.data, count);
break;
case VIRTIO_SND_CTL_TYPE_IEC958:
memcpy(&kvalue->value.iec958, &uvalue->value.iec958,
sizeof(kvalue->value.iec958));
break;
}
return virtsnd_ctl_msg_send_sync(snd, msg);
}
/**
* virtsnd_kctl_tlv_op() - Perform an operation on the control's metadata.
* @kcontrol: ALSA control element.
* @op_flag: Operation code (SNDRV_CTL_TLV_OP_XXX).
* @size: Size of the TLV data in bytes.
* @utlv: TLV data.
*
* Context: Process context.
* Return: 0 on success, -errno on failure.
*/
static int virtsnd_kctl_tlv_op(struct snd_kcontrol *kcontrol, int op_flag,
unsigned int size, unsigned int __user *utlv)
{
struct virtio_snd *snd = kcontrol->private_data;
struct virtio_snd_msg *msg;
struct virtio_snd_ctl_hdr *hdr;
unsigned int *tlv;
struct scatterlist sg;
int rc;
msg = virtsnd_ctl_msg_alloc(sizeof(*hdr), sizeof(struct virtio_snd_hdr),
GFP_KERNEL);
if (!msg)
return -ENOMEM;
tlv = kzalloc(size, GFP_KERNEL);
if (!tlv) {
rc = -ENOMEM;
goto on_msg_unref;
}
sg_init_one(&sg, tlv, size);
hdr = virtsnd_ctl_msg_request(msg);
hdr->control_id = cpu_to_le32(kcontrol->private_value);
switch (op_flag) {
case SNDRV_CTL_TLV_OP_READ:
hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_TLV_READ);
rc = virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false);
if (!rc) {
if (copy_to_user(utlv, tlv, size))
rc = -EFAULT;
}
break;
case SNDRV_CTL_TLV_OP_WRITE:
case SNDRV_CTL_TLV_OP_CMD:
if (op_flag == SNDRV_CTL_TLV_OP_WRITE)
hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_TLV_WRITE);
else
hdr->hdr.code =
cpu_to_le32(VIRTIO_SND_R_CTL_TLV_COMMAND);
if (copy_from_user(tlv, utlv, size)) {
rc = -EFAULT;
goto on_msg_unref;
} else {
rc = virtsnd_ctl_msg_send(snd, msg, &sg, NULL, false);
}
break;
default:
rc = -EINVAL;
/* We never get here - we listed all values for op_flag */
WARN_ON(1);
goto on_msg_unref;
}
kfree(tlv);
return rc;
on_msg_unref:
virtsnd_ctl_msg_unref(msg);
kfree(tlv);
return rc;
}
/**
* virtsnd_kctl_get_enum_items() - Query items for the ENUMERATED element type.
* @snd: VirtIO sound device.
* @cid: Control element ID.
*
* This function is called during initial device initialization.
*
* Context: Any context that permits to sleep.
* Return: 0 on success, -errno on failure.
*/
static int virtsnd_kctl_get_enum_items(struct virtio_snd *snd, unsigned int cid)
{
struct virtio_device *vdev = snd->vdev;
struct virtio_snd_ctl_info *kinfo = &snd->kctl_infos[cid];
struct virtio_kctl *kctl = &snd->kctls[cid];
struct virtio_snd_msg *msg;
struct virtio_snd_ctl_hdr *hdr;
unsigned int n = le32_to_cpu(kinfo->value.enumerated.items);
struct scatterlist sg;
msg = virtsnd_ctl_msg_alloc(sizeof(*hdr),
sizeof(struct virtio_snd_hdr), GFP_KERNEL);
if (!msg)
return -ENOMEM;
kctl->items = devm_kcalloc(&vdev->dev, n, sizeof(*kctl->items),
GFP_KERNEL);
if (!kctl->items) {
virtsnd_ctl_msg_unref(msg);
return -ENOMEM;
}
sg_init_one(&sg, kctl->items, n * sizeof(*kctl->items));
hdr = virtsnd_ctl_msg_request(msg);
hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_ENUM_ITEMS);
hdr->control_id = cpu_to_le32(cid);
return virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false);
}
/**
* virtsnd_kctl_parse_cfg() - Parse the control element 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_kctl_parse_cfg(struct virtio_snd *snd)
{
struct virtio_device *vdev = snd->vdev;
u32 i;
int rc;
virtio_cread_le(vdev, struct virtio_snd_config, controls,
&snd->nkctls);
if (!snd->nkctls)
return 0;
snd->kctl_infos = devm_kcalloc(&vdev->dev, snd->nkctls,
sizeof(*snd->kctl_infos), GFP_KERNEL);
if (!snd->kctl_infos)
return -ENOMEM;
snd->kctls = devm_kcalloc(&vdev->dev, snd->nkctls, sizeof(*snd->kctls),
GFP_KERNEL);
if (!snd->kctls)
return -ENOMEM;
rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_CTL_INFO, 0, snd->nkctls,
sizeof(*snd->kctl_infos), snd->kctl_infos);
if (rc)
return rc;
for (i = 0; i < snd->nkctls; ++i) {
struct virtio_snd_ctl_info *kinfo = &snd->kctl_infos[i];
unsigned int type = le32_to_cpu(kinfo->type);
if (type == VIRTIO_SND_CTL_TYPE_ENUMERATED) {
rc = virtsnd_kctl_get_enum_items(snd, i);
if (rc)
return rc;
}
}
return 0;
}
/**
* virtsnd_kctl_build_devs() - Build ALSA control elements.
* @snd: VirtIO sound device.
*
* Context: Any context that permits to sleep.
* Return: 0 on success, -errno on failure.
*/
int virtsnd_kctl_build_devs(struct virtio_snd *snd)
{
unsigned int cid;
for (cid = 0; cid < snd->nkctls; ++cid) {
struct virtio_snd_ctl_info *kinfo = &snd->kctl_infos[cid];
struct virtio_kctl *kctl = &snd->kctls[cid];
struct snd_kcontrol_new kctl_new;
unsigned int i;
int rc;
memset(&kctl_new, 0, sizeof(kctl_new));
kctl_new.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
kctl_new.name = kinfo->name;
kctl_new.index = le32_to_cpu(kinfo->index);
for (i = 0; i < ARRAY_SIZE(g_v2a_access_map); ++i)
if (le32_to_cpu(kinfo->access) & (1 << i))
kctl_new.access |= g_v2a_access_map[i];
if (kctl_new.access & (SNDRV_CTL_ELEM_ACCESS_TLV_READ |
SNDRV_CTL_ELEM_ACCESS_TLV_WRITE |
SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND)) {
kctl_new.access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
kctl_new.tlv.c = virtsnd_kctl_tlv_op;
}
kctl_new.info = virtsnd_kctl_info;
kctl_new.get = virtsnd_kctl_get;
kctl_new.put = virtsnd_kctl_put;
kctl_new.private_value = cid;
kctl->kctl = snd_ctl_new1(&kctl_new, snd);
if (!kctl->kctl)
return -ENOMEM;
rc = snd_ctl_add(snd->card, kctl->kctl);
if (rc)
return rc;
}
return 0;
}
/**
* virtsnd_kctl_event() - Handle the control element event notification.
* @snd: VirtIO sound device.
* @event: VirtIO sound event.
*
* Context: Interrupt context.
*/
void virtsnd_kctl_event(struct virtio_snd *snd, struct virtio_snd_event *event)
{
struct virtio_snd_ctl_event *kevent =
(struct virtio_snd_ctl_event *)event;
struct virtio_kctl *kctl;
unsigned int cid = le16_to_cpu(kevent->control_id);
unsigned int mask = 0;
unsigned int i;
if (cid >= snd->nkctls)
return;
for (i = 0; i < ARRAY_SIZE(g_v2a_mask_map); ++i)
if (le16_to_cpu(kevent->mask) & (1 << i))
mask |= g_v2a_mask_map[i];
kctl = &snd->kctls[cid];
snd_ctl_notify(snd->card, mask, &kctl->kctl->id);
}
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