Documentation/driver-api/soundwire/stream.rst
Source file repositories/reference/linux-study-clean/Documentation/driver-api/soundwire/stream.rst
File Facts
- System
- Linux kernel
- Corpus path
Documentation/driver-api/soundwire/stream.rst- Extension
.rst- Size
- 23405 bytes
- Lines
- 528
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: documentation
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
=========================
Audio Stream in SoundWire
=========================
An audio stream is a logical or virtual connection created between
(1) System memory buffer(s) and Codec(s)
(2) DSP memory buffer(s) and Codec(s)
(3) FIFO(s) and Codec(s)
(4) Codec(s) and Codec(s)
which is typically driven by a DMA(s) channel through the data link. An
audio stream contains one or more channels of data. All channels within
stream must have same sample rate and same sample size.
Assume a stream with two channels (Left & Right) is opened using SoundWire
interface. Below are some ways a stream can be represented in SoundWire.
Stream Sample in memory (System memory, DSP memory or FIFOs) ::
-------------------------
| L | R | L | R | L | R |
-------------------------
Example 1: Stereo Stream with L and R channels is rendered from Master to
Slave. Both Master and Slave is using single port. ::
+---------------+ Clock Signal +---------------+
| Master +----------------------------------+ Slave |
| Interface | | Interface |
| | | 1 |
| | Data Signal | |
| L + R +----------------------------------+ L + R |
| (Data) | Data Direction | (Data) |
+---------------+ +-----------------------> +---------------+
Example 2: Stereo Stream with L and R channels is captured from Slave to
Master. Both Master and Slave is using single port. ::
+---------------+ Clock Signal +---------------+
| Master +----------------------------------+ Slave |
| Interface | | Interface |
| | | 1 |
| | Data Signal | |
| L + R +----------------------------------+ L + R |
| (Data) | Data Direction | (Data) |
+---------------+ <-----------------------+ +---------------+
Example 3: Stereo Stream with L and R channels is rendered by Master. Each
of the L and R channel is received by two different Slaves. Master and both
Slaves are using single port. ::
+---------------+ Clock Signal +---------------+
| Master +---------+------------------------+ Slave |
| Interface | | | Interface |
| | | | 1 |
| | | Data Signal | |
| L + R +---+------------------------------+ L |
| (Data) | | | Data Direction | (Data) |
+---------------+ | | +-------------> +---------------+
| |
| |
| | +---------------+
| +----------------------> | Slave |Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.