class GetVmo

Requests a shared buffer to be used for moving bulk audio data between client and driver.

The client requests `min_frames` as the size for part of the ring buffer it needs.

The driver returns the actual size of allocated ring buffer space in `num_frames`.

`num_frames` must be at least `min_frames` plus `driver_transfer_bytes` (in frames) such

that ring buffer contents can be transfered in and out, or else the call must be failed

with GetVmoError.INVALID_ARGS.

The driver may increase the ring buffer size beyond `min_frames` plus

`driver_transfer_bytes` (in frames) due to any internal requirements, for instance

alignment.

Clients can treat the entire returned ring buffer as safe to access, except for the

`driver_transfer_bytes` immediately adjacent to the current position, see the

`driver_transfer_bytes` parameter specification in `RingBufferProperties` for more details.

The returned VMO handle must include ZX_RIGHT_TRANSFER, ZX_RIGHT_READ and ZX_RIGHT_MAP.

If the ring buffer is "outgoing" (conveys audio data from client to device), then the

handle must also include ZX_RIGHT_WRITE.

If `clock_recovery_notifications_per_ring` is non-zero, the driver will send replies to

`WatchClockRecoveryPositionInfo` client requests at most at

`clock_recovery_notifications_per_ring` frequency. These notifications are meant to be used

for clock recovery.