High Definition Audio Overview (D27:F0); Dock Sequence; High Definition Audio Docking (Mobile Only) - Intel 6 SERIES CHIPSET - DATASHEET 01-2011 Datasheet

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5.22 Intel
The PCH High Definition Audio (HDA) controller communicates with the external
codec(s) over the Intel High Definition Audio serial link. The controller consists of a set
of DMA engines that are used to move samples of digitally encoded data between
system memory and an external codec(s). The PCH implements four output DMA
engines and 4 input DMA engines. The output DMA engines move digital data from
system memory to a D-A converter in a codec. The PCH implements a single Serial
Data Output signal (HDA_SDO) that is connected to all external codecs. The input DMA
engines move digital data from the A-D converter in the codec to system memory. The
PCH implements four Serial Digital Input signals (HDA_SDI[3:0]) supporting up to four
codecs.
Audio software renders outbound and processes inbound data to/from buffers in
system memory. The location of individual buffers is described by a Buffer Descriptor
List (BDL) that is fetched and processed by the controller. The data in the buffers is
arranged in a predefined format. The output DMA engines fetch the digital data from
memory and reformat it based on the programmed sample rate, bit/sample and
number of channels. The data from the output DMA engines is then combined and
serially sent to the external codecs over the Intel High Definition Audio link. The input
DMA engines receive data from the codecs over the Intel High Definition Audio link and
format the data based on the programmable attributes for that stream. The data is
then written to memory in the predefined format for software to process. Each DMA
engine moves one stream of data. A single codec can accept or generate multiple
streams of data, one for each A-D or D-A converter in the codec. Multiple codecs can
accept the same output stream processed by a single DMA engine.
Codec commands and responses are also transported to and from the codecs using
DMA engines.
The PCH HD audio controller supports the Function Level Reset (FLR).
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5.22.1 Intel
5.22.1.1

Dock Sequence

Note that this sequence is followed when the system is running and a docking event
occurs.
1. Since the PCH supports docking, the Docking Supported (DCKSTS. DS) bit defaults
to a 1. POST BIOS and ACPI BIOS software uses this bit to determine if the HD
Audio controller supports docking. BIOS may write a 0 to this R/WO bit during
POST to effectively turn off the docking feature.
2. After reset in the undocked quiescent state, the Dock Attach (DCKCTL.DA) bit and
the Dock Mate (DCKSTS.DM) bit are both deasserted. The HDA_DOCK_EN# signal
is deasserted and HDA_DOCK_RST# is asserted. Bit Clock, SYNC and SDO signals
may or may no be running at the point in time that the docking event occurs.
3. The physical docking event is signaled to ACPI BIOS software using ACPI control
methods. This is normally done through a GPIO signal on the PCH and is outside
the scope of this section of the specification.
4. ACPI BIOS software first checks that the docking is supported using DCKSTS.DS=1
and that the DCKSTS.DM=0 and then initiates the docking sequence by writing a 1
to the DCKCTL.DA bit.
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High Definition Audio Overview (D27:F0)

High Definition Audio Docking (Mobile Only)

Functional Description
Datasheet