Exynos uses the usb audio offloading functions to save power consumption
in the usb audio device. The audio control interface is processed in the
existing usb path, and the audio stream interface is processed in the
audio path.
Through communication between AP usb and audio usb f/w, usb audio device
connection information, xhci memory information, etc. are notified to usb
audio f/w so that the abox directly controls xhci transmission.
Vendor's hooking interface is required for this functions. Throught this
interface, information such as usb audio device connection information,
pcm interface information, sample rate setting, xhci memory, full descriptor
of connected device, and setting point can be transmitted to usb audio f/w.
the usb audio f/w can set up and interface, transmit audio data, etc. through
the received information.
This patchset includes the following for using usb audio offloading:
- vendor's hooking interface
- vendor's hooking interface calling point
- user using vendor's hooking interface
Oh Eomji (3):
sound: usb: Add vendor's hooking interface
sound: usb: Calling vendor's call-back function within usb audio
operation.
sound: usb: Exynos usb audio offloading driver
sound/usb/Kconfig | 9 +
sound/usb/Makefile | 2 +
sound/usb/card.c | 119 +++++++++
sound/usb/card.h | 20 ++
sound/usb/exynos_usb_audio.c | 560 +++++++++++++++++++++++++++++++++++++++++++
sound/usb/exynos_usb_audio.h | 150 ++++++++++++
sound/usb/pcm.c | 37 +++
sound/usb/stream.c | 2 +
sound/usb/usbaudio.h | 45 ++++
9 files changed, 944 insertions(+)
create mode 100644 sound/usb/exynos_usb_audio.c
create mode 100644 sound/usb/exynos_usb_audio.h
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2.7.4
