Commits
Oleksandr Andrushchenko committed 1cee559351a
ALSA: xen-front: Implement ALSA virtual sound driver Implement essential initialization of the sound driver: - introduce required data structures - handle driver registration - handle sound card registration - register sound driver on backend connection - remove sound driver on backend disconnect Initialize virtual sound card with streams according to the Xen store configuration. Implement ALSA driver operations including: - manage frontend/backend shared buffers - manage Xen bus event channel states Implement requests from front to back for ALSA PCM operations. - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS notifications from the backend when stream position advances during playback/capture. The event carries a value of how many octets were played/captured at the time of the event. - implement explicit stream parameter negotiation between backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request to read/update configuration space for the parameter given: request passes desired parameter interval and the response to this request returns min/max interval for the parameter to be used. Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>