Introduction to SoundWire
summary
SoundWire is a MIPI audio bus: a 2-pin clock+data serial, dual-data-rate link with dynamic frame sizes, runtime clock scaling to 12.8 MHz and a built-in bulk transfer channel for large blobs. It supports both PCM and PDM, exposes up to 11 slaves and 15 logical data ports (port 0 = bulk), uses 48-bit device IDs with master-assigned 4-bit device numbers, and requires software-driven enumeration. A Linux subsystem is already merged into Linux 4.16 with streaming in 4.20 and Intel/Cadence controller patches in-tree; bank switching enables glitch-free runtime stream changes.
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chapters (27)
- 0:00Introduction
- 1:14Bit Standards
- 1:45Existing Audio Standards
- 4:21How does SoundWire work
- 6:24SoundWire Protocol
- 8:19At Runtime
- 11:10Master
- 13:45Data Ports
- 15:14Frame
- 17:38Frame Examples
- 19:21Control Work
- 22:51Device Address
- 24:44Device Number
- 26:17Enumeration
- 27:04Slave Status
- 27:22Dynamic Device Number
- 28:05Disco
- 29:35Linux
- 32:41Bus Master API
- 33:36Master Ops
- 36:55Slave Driver
- 38:02Slave Operations
- 38:26Disco Properties
- 39:40ReadWrite APIs
- 40:09Audio Stream
- 41:31Prepare Stream
- 42:42Configuration Spec
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