xref: /linux/Documentation/i2c/busses/i2c-taos-evm.rst (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1==========================
2Kernel driver i2c-taos-evm
3==========================
4
5Author: Jean Delvare <jdelvare@suse.de>
6
7This is a driver for the evaluation modules for TAOS I2C/SMBus chips.
8The modules include an SMBus master with limited capabilities, which can
9be controlled over the serial port. Virtually all evaluation modules
10are supported, but a few lines of code need to be added for each new
11module to instantiate the right I2C chip on the bus. Obviously, a driver
12for the chip in question is also needed.
13
14Currently supported devices are:
15
16* TAOS TSL2550 EVM
17
18For additional information on TAOS products, please see
19  http://www.taosinc.com/
20
21
22Using this driver
23-----------------
24
25In order to use this driver, you'll need the serport driver, and the
26inputattach tool, which is part of the input-utils package. The following
27commands will tell the kernel that you have a TAOS EVM on the first
28serial port::
29
30  # modprobe serport
31  # inputattach --taos-evm /dev/ttyS0
32
33
34Technical details
35-----------------
36
37Only 4 SMBus transaction types are supported by the TAOS evaluation
38modules:
39* Receive Byte
40* Send Byte
41* Read Byte
42* Write Byte
43
44The communication protocol is text-based and pretty simple. It is
45described in a PDF document on the CD which comes with the evaluation
46module. The communication is rather slow, because the serial port has
47to operate at 1200 bps. However, I don't think this is a big concern in
48practice, as these modules are meant for evaluation and testing only.
49