Documentation/i2c/busses/i2c-ali15x3.rst

Source file repositories/reference/linux-study-clean/Documentation/i2c/busses/i2c-ali15x3.rst

File Facts

System: Linux kernel
Corpus path: Documentation/i2c/busses/i2c-ali15x3.rst
Extension: .rst
Size: 3706 bytes
Lines: 123
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.
Touches IRQ or DMA behavior; this matters for the representative real-device path.

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 i2c-ali15x3
=========================

Supported adapters:
  * Acer Labs, Inc. ALI 1533 and 1543C (south bridge)

    Datasheet: Now under NDA
	http://www.ali.com.tw/

Authors:
	- Frodo Looijaard <frodol@dds.nl>,
	- Philip Edelbrock <phil@netroedge.com>,
	- Mark D. Studebaker <mdsxyz123@yahoo.com>

Module Parameters
-----------------

* force_addr: int
    Initialize the base address of the i2c controller


Notes
-----

The force_addr parameter is useful for boards that don't set the address in
the BIOS. Does not do a PCI force; the device must still be present in
lspci. Don't use this unless the driver complains that the base address is
not set.

Example::

    modprobe i2c-ali15x3 force_addr=0xe800

SMBus periodically hangs on ASUS P5A motherboards and can only be cleared
by a power cycle. Cause unknown (see Issues below).


Description
-----------

This is the driver for the SMB Host controller on Acer Labs Inc. (ALI)
M1541 and M1543C South Bridges.

The M1543C is a South bridge for desktop systems.

The M1541 is a South bridge for portable systems.

They are part of the following ALI chipsets:

 * "Aladdin Pro 2" includes the M1621 Slot 1 North bridge with AGP and
   100MHz CPU Front Side bus
 * "Aladdin V" includes the M1541 Socket 7 North bridge with AGP and 100MHz
   CPU Front Side bus

   Some Aladdin V motherboards:
	- Asus P5A
	- Atrend ATC-5220
	- BCM/GVC VP1541
	- Biostar M5ALA
	- Gigabyte GA-5AX (Generally doesn't work because the BIOS doesn't
	  enable the 7101 device!)
	- Iwill XA100 Plus
	- Micronics C200
	- Microstar (MSI) MS-5169

  * "Aladdin IV" includes the M1541 Socket 7 North bridge
    with host bus up to 83.3 MHz.

For an overview of these chips see http://www.acerlabs.com. At this time the

Annotation

Atlas domain: Support Tooling And Documentation / Documentation.
Implementation status: atlas-only.
IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

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.