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docs: i2c: call it "I2C" consistently

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Uppercase "I2C" is used almost everywhere in the docs, but the lowercase
version "i2c" is used somewhere. Use the uppercase form consistently.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Acked-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Luca Ceresoli
2020-01-29 16:19:29 +01:00
committed by Wolfram Sang
parent 020bc5b929
commit 2f07c05f14
8 changed files with 53 additions and 53 deletions
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18
Documentation/i2c/dev-interface.rst
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@@ -2,26 +2,26 @@
I2C Device Interface
====================
Usually, i2c devices are controlled by a kernel driver. But it is also
Usually, I2C devices are controlled by a kernel driver. But it is also
possible to access all devices on an adapter from userspace, through
the /dev interface. You need to load module i2c-dev for this.
Each registered i2c adapter gets a number, counting from 0. You can
Each registered I2C adapter gets a number, counting from 0. You can
examine /sys/class/i2c-dev/ to see what number corresponds to which adapter.
Alternatively, you can run "i2cdetect -l" to obtain a formatted list of all
i2c adapters present on your system at a given time. i2cdetect is part of
I2C adapters present on your system at a given time. i2cdetect is part of
the i2c-tools package.
I2C device files are character device files with major device number 89
and a minor device number corresponding to the number assigned as
explained above. They should be called "i2c-%d" (i2c-0, i2c-1, ...,
i2c-10, ...). All 256 minor device numbers are reserved for i2c.
i2c-10, ...). All 256 minor device numbers are reserved for I2C.
C example
=========
So let's say you want to access an i2c adapter from a C program.
So let's say you want to access an I2C adapter from a C program.
First, you need to include these two headers::
#include <linux/i2c-dev.h>
@@ -66,7 +66,7 @@ the device supports them. Both are illustrated below::
/* Using SMBus commands */
res = i2c_smbus_read_word_data(file, reg);
if (res < 0) {
/* ERROR HANDLING: i2c transaction failed */
/* ERROR HANDLING: I2C transaction failed */
} else {
/* res contains the read word */
}
@@ -79,12 +79,12 @@ the device supports them. Both are illustrated below::
buf[1] = 0x43;
buf[2] = 0x65;
if (write(file, buf, 3) != 3) {
/* ERROR HANDLING: i2c transaction failed */
/* ERROR HANDLING: I2C transaction failed */
}
/* Using I2C Read, equivalent of i2c_smbus_read_byte(file) */
if (read(file, buf, 1) != 1) {
/* ERROR HANDLING: i2c transaction failed */
/* ERROR HANDLING: I2C transaction failed */
} else {
/* buf[0] contains the read byte */
}
@@ -144,7 +144,7 @@ The following IOCTLs are defined:
If possible, use the provided ``i2c_smbus_*`` methods described below instead
of issuing direct ioctls.
You can do plain i2c transactions by using read(2) and write(2) calls.
You can do plain I2C transactions by using read(2) and write(2) calls.
You do not need to pass the address byte; instead, set it through
ioctl I2C_SLAVE before you try to access the device.