Documentation/i2c/summary.rst

2 Introduction to I2C and SMBus
6 a protocol developed by Philips. It is a slow two-wire protocol (variable
7 speed, up to 400 kHz), with a high speed extension (3.4 MHz).  It provides
8 an inexpensive bus for connecting many types of devices with infrequent or
14 The latest official I2C specification is the `"I2C-bus specification and user
16 published by NXP Semiconductors. However, you need to log-in to the site to
18 `here <https://web.archive.org/web/20210813122132/https://www.nxp.com/docs/en/user-guide/UM10204.pd…
21 a subset of I2C protocols and signaling.  Many I2C devices will work on an
22 SMBus, but some SMBus protocols add semantics beyond what is required to
28 use its protocols on many I2C systems.  However, there are systems that don't
37 one or more *master* chips and one or more *slave* chips.
39 .. kernel-figure::  i2c_bus.svg
40    :alt:    Simple I2C bus with one master and 3 slaves
48 An **algorithm** contains general code that can be used to implement a
53 A **slave** chip is a node that responds to communications when addressed
55 in a directory specific to the feature they provide, for example
57 video-related chips.
60 I2C adapter, and drivers for your I2C devices (usually one driver for each