Documentation/w1/slaves/w1_ds28e04.rst
Source file repositories/reference/linux-study-clean/Documentation/w1/slaves/w1_ds28e04.rst
File Facts
- System
- Linux kernel
- Corpus path
Documentation/w1/slaves/w1_ds28e04.rst- Extension
.rst- Size
- 1314 bytes
- Lines
- 42
- 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.
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
========================
Kernel driver w1_ds28e04
========================
Supported chips:
* Maxim DS28E04-100 4096-Bit Addressable 1-Wire EEPROM with PIO
supported family codes:
================= ====
W1_FAMILY_DS28E04 0x1C
================= ====
Author: Markus Franke, <franke.m@sebakmt.com> <franm@hrz.tu-chemnitz.de>
Description
-----------
Support is provided through the sysfs files "eeprom" and "pio". CRC checking
during memory accesses can optionally be enabled/disabled via the device
attribute "crccheck". The strong pull-up can optionally be enabled/disabled
via the module parameter "w1_strong_pullup".
Memory Access
A read operation on the "eeprom" file reads the given amount of bytes
from the EEPROM of the DS28E04.
A write operation on the "eeprom" file writes the given byte sequence
to the EEPROM of the DS28E04. If CRC checking mode is enabled only
fully aligned blocks of 32 bytes with valid CRC16 values (in bytes 30
and 31) are allowed to be written.
PIO Access
The 2 PIOs of the DS28E04-100 are accessible via the "pio" sysfs file.
The current status of the PIO's is returned as an 8 bit value. Bit 0/1
represent the state of PIO_0/PIO_1. Bits 2..7 do not care. The PIO's are
driven low-active, i.e. the driver delivers/expects low-active values.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.