minix/drivers/cat24c256
Thomas Cort 437177b028 i2c: increase BUFLEN/CMDLEN to 128, add page flag.
128 byte reads are much more common than 32 byte reads. The message
passing + setup/teardown for a read is much more expensive, in terms
of time, than the reading itself. A slightly bigger struct is well
worth the time savings. This reduces read times for /dev/eeprom
from 57 seconds per 4KB to 14 seconds.

Additionally, make sending the page address in the eeprom driver
and utility optional. This can save a little time when reading
within the same page and allows support for smaller devices that
don't support pages (example: chips containing EDID).

Change-Id: Ie48087caee40c11fa241d1555fce9309ddd27b43
2013-07-27 08:21:37 -04:00
..
cat24c256.c i2c: increase BUFLEN/CMDLEN to 128, add page flag. 2013-07-27 08:21:37 -04:00
Makefile cat24c256: driver for the cat24c256 i2c eeprom 2013-07-15 17:03:18 -04:00
README.txt cat24c256: driver for the cat24c256 i2c eeprom 2013-07-15 17:03:18 -04:00

CAT24C256 Driver (EEPROM)
=========================

Overview
--------

This is the driver for the EEPROM chip commonly found on the BeagleBone
and the BeagleBone Black as well as capes and expansion boards.

Testing the Code
----------------

Starting up an instance:

/bin/service up /usr/sbin/cat24c256 -dev /dev/eepromb1s50 -label cat24c256.1.50 -args 'bus=1 address=0x50'