Commit Graph

3 Commits

Author SHA1 Message Date
Manos Pitsidianakis
18a752810f virtio-sound: implement audio output (TX)
Handle output IO messages in the transmit (TX) virtqueue.

It allocates a VirtIOSoundPCMBuffer for each IO message and copies the
data buffer to it. When the IO buffer is written to the host's sound
card, the guest will be notified that it has been consumed.

The lifetime of an IO message is:

1. Guest sends IO message to TX virtqueue.
2. QEMU adds it to the appropriate stream's IO buffer queue.
3. Sometime later, the host audio backend calls the output callback,
   virtio_snd_pcm_out_cb(), which is defined with an AUD_open_out()
   call. The callback gets an available number of bytes the backend can
   receive. Then it writes data from the IO buffer queue to the backend.
   If at any time a buffer is exhausted, it is returned to the guest as
   completed.
4. If the guest releases the stream, its buffer queue is flushed by
   attempting to write any leftover data to the audio backend and
   releasing all IO messages back to the guest. This is how according to
   the spec the guest knows the release was successful.

Based-on: 5a2f350eec
Signed-off-by: Igor Skalkin <Igor.Skalkin@opensynergy.com>
Signed-off-by: Anton Yakovlev <Anton.Yakovlev@opensynergy.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <b7c6fc458c763d09a4abbcb620ae9b220afa5b8f.1698062525.git.manos.pitsidianakis@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-11-07 03:39:10 -05:00
Manos Pitsidianakis
eb9ad377bb virtio-sound: handle control messages and streams
Receive guest requests in the control (CTRL) queue of the virtio sound
device and reply with a NOT SUPPORTED error to all control commands.

The receiving handler is virtio_snd_handle_ctrl(). It stores all control
messages in the queue in the device's command queue. Then it calls
virtio_snd_process_cmdq() to handle each message.

The handler is process_cmd() which replies with VIRTIO_SND_S_NOT_SUPP.

Based-on: 5a2f350eec
Signed-off-by: Igor Skalkin <Igor.Skalkin@opensynergy.com>
Signed-off-by: Anton Yakovlev <Anton.Yakovlev@opensynergy.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <3224aff87e7c4f2777bfe1bbbbca93b72525992c.1698062525.git.manos.pitsidianakis@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-11-07 03:39:10 -05:00
Manos Pitsidianakis
2880e676c0 Add virtio-sound device stub
Add a new VIRTIO device for the virtio sound device id. Functionality
will be added in the following commits.

Based-on: 5a2f350eec
Signed-off-by: Igor Skalkin <Igor.Skalkin@opensynergy.com>
Signed-off-by: Anton Yakovlev <Anton.Yakovlev@opensynergy.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <f9678a41fe97b5886c1b04795f1be046509de866.1698062525.git.manos.pitsidianakis@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-11-07 03:39:10 -05:00