From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luca Ceresoli Subject: [PATCH 02/26] docs: i2c: summary: extend introduction Date: Sun, 5 Jan 2020 23:49:48 +0100 Message-ID: <20200105225012.11701-2-luca@lucaceresoli.net> References: <20200105224006.10321-1-luca@lucaceresoli.net> <20200105225012.11701-1-luca@lucaceresoli.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200105225012.11701-1-luca@lucaceresoli.net> Sender: linux-kernel-owner@vger.kernel.org To: linux-doc@vger.kernel.org, linux-i2c@vger.kernel.org Cc: Luca Ceresoli , Wolfram Sang , Peter Rosin , linux-kernel@vger.kernel.org List-Id: linux-i2c@vger.kernel.org - state the "official" name (I²C, not I2C, according to the spec) at the beginning but keep using the more practical I2C elsewhere - mention some known different names - add link to the specification document Signed-off-by: Luca Ceresoli --- Documentation/i2c/summary.rst | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/Documentation/i2c/summary.rst b/Documentation/i2c/summary.rst index 3a24eac17375..b7d3e620155b 100644 --- a/Documentation/i2c/summary.rst +++ b/Documentation/i2c/summary.rst @@ -2,12 +2,18 @@ I2C and SMBus ============= -I2C (pronounce: I squared C) is a protocol developed by Philips. It is a -slow two-wire protocol (variable speed, up to 400 kHz), with a high speed -extension (3.4 MHz). It provides an inexpensive bus for connecting many -types of devices with infrequent or low bandwidth communications needs. -I2C is widely used with embedded systems. Some systems use variants that -don't meet branding requirements, and so are not advertised as being I2C. +I²C (pronounce: I squared C and written I2C in the kernel documentation) is +a protocol developed by Philips. It is a slow two-wire protocol (variable +speed, up to 400 kHz), with a high speed extension (3.4 MHz). It provides +an inexpensive bus for connecting many types of devices with infrequent or +low bandwidth communications needs. I2C is widely used with embedded +systems. Some systems use variants that don't meet branding requirements, +and so are not advertised as being I2C but with different names, e.g. TWI +(Two Wire Interface), IIC. + +The official I2C specification is the `"I2C-bus specification and user +manual" (UM10204) `_ +published by NXP Semiconductors. SMBus (System Management Bus) is based on the I2C protocol, and is mostly a subset of I2C protocols and signaling. Many I2C devices will work on an -- 2.24.1