Implementation of support for audio controls in accordance with the
extension of the virtio sound device specification [1] planned for
virtio-v1.3-cs01.
The device can announce the VIRTIO_SND_F_CTLS feature. If the feature is
negotiated, then an additional field appears in the configuration space:
struct virtio_snd_config {
...
/* number of available control elements */
__le32 controls;
};
The driver can send the following requests to manage audio controls:
enum {
...
/* control element request types */
VIRTIO_SND_R_CTL_INFO = 0x0300,
VIRTIO_SND_R_CTL_ENUM_ITEMS,
VIRTIO_SND_R_CTL_READ,
VIRTIO_SND_R_CTL_WRITE,
VIRTIO_SND_R_CTL_TLV_READ,
VIRTIO_SND_R_CTL_TLV_WRITE,
VIRTIO_SND_R_CTL_TLV_COMMAND,
...
};
And the device can send the following audio control event notification:
enum {
...
/* control element event types */
VIRTIO_SND_EVT_CTL_NOTIFY = 0x1200,
...
};
See additional details in [1].
[1] https://lists.oasis-open.org/archives/virtio-comment/202104/msg00013.html
Signed-off-by: Anton Yakovlev <anton.yakovlev@opensynergy.com>
Signed-off-by: Aiswarya Cyriac <aiswarya.cyriac@opensynergy.com>
Link: https://lore.kernel.org/r/20240115133654.576068-2-aiswarya.cyriac@opensynergy.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Bug: 330891925
Change-Id: I4c70787a920bc4a7cf82b8115fc9f0a6c77b4859
(cherry picked from commit d6568e3de42dd971a1356f7ba581e6600d53f0a0)
Signed-off-by: Marcin Radomski <dextero@google.com>
e7f7d55471