[PATCH] I2C: Clarify the usage of i2c-dev.h
Upon suggestion by Nils Roeder, here is an update to the i2c documentation to clarify which header files user-space applications relying on the i2c-dev interface should include. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
parent
a68e2f4895
commit
1d772e2587
1 changed files with 7 additions and 4 deletions
|
@ -14,9 +14,12 @@ C example
|
|||
=========
|
||||
|
||||
So let's say you want to access an i2c adapter from a C program. The
|
||||
first thing to do is `#include <linux/i2c.h>" and "#include <linux/i2c-dev.h>.
|
||||
Yes, I know, you should never include kernel header files, but until glibc
|
||||
knows about i2c, there is not much choice.
|
||||
first thing to do is "#include <linux/i2c-dev.h>". Please note that
|
||||
there are two files named "i2c-dev.h" out there, one is distributed
|
||||
with the Linux kernel and is meant to be included from kernel
|
||||
driver code, the other one is distributed with lm_sensors and is
|
||||
meant to be included from user-space programs. You obviously want
|
||||
the second one here.
|
||||
|
||||
Now, you have to decide which adapter you want to access. You should
|
||||
inspect /sys/class/i2c-dev/ to decide this. Adapter numbers are assigned
|
||||
|
@ -78,7 +81,7 @@ Full interface description
|
|||
==========================
|
||||
|
||||
The following IOCTLs are defined and fully supported
|
||||
(see also i2c-dev.h and i2c.h):
|
||||
(see also i2c-dev.h):
|
||||
|
||||
ioctl(file,I2C_SLAVE,long addr)
|
||||
Change slave address. The address is passed in the 7 lower bits of the
|
||||
|
|
Loading…
Reference in a new issue