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2*4882a593SmuzhiyunKernel driver i2c-taos-evm
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5*4882a593SmuzhiyunAuthor: Jean Delvare <jdelvare@suse.de>
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7*4882a593SmuzhiyunThis is a driver for the evaluation modules for TAOS I2C/SMBus chips.
8*4882a593SmuzhiyunThe modules include an SMBus master with limited capabilities, which can
9*4882a593Smuzhiyunbe controlled over the serial port. Virtually all evaluation modules
10*4882a593Smuzhiyunare supported, but a few lines of code need to be added for each new
11*4882a593Smuzhiyunmodule to instantiate the right I2C chip on the bus. Obviously, a driver
12*4882a593Smuzhiyunfor the chip in question is also needed.
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14*4882a593SmuzhiyunCurrently supported devices are:
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16*4882a593Smuzhiyun* TAOS TSL2550 EVM
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18*4882a593SmuzhiyunFor additional information on TAOS products, please see
19*4882a593Smuzhiyun  http://www.taosinc.com/
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22*4882a593SmuzhiyunUsing this driver
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25*4882a593SmuzhiyunIn order to use this driver, you'll need the serport driver, and the
26*4882a593Smuzhiyuninputattach tool, which is part of the input-utils package. The following
27*4882a593Smuzhiyuncommands will tell the kernel that you have a TAOS EVM on the first
28*4882a593Smuzhiyunserial port::
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30*4882a593Smuzhiyun  # modprobe serport
31*4882a593Smuzhiyun  # inputattach --taos-evm /dev/ttyS0
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34*4882a593SmuzhiyunTechnical details
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37*4882a593SmuzhiyunOnly 4 SMBus transaction types are supported by the TAOS evaluation
38*4882a593Smuzhiyunmodules:
39*4882a593Smuzhiyun* Receive Byte
40*4882a593Smuzhiyun* Send Byte
41*4882a593Smuzhiyun* Read Byte
42*4882a593Smuzhiyun* Write Byte
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44*4882a593SmuzhiyunThe communication protocol is text-based and pretty simple. It is
45*4882a593Smuzhiyundescribed in a PDF document on the CD which comes with the evaluation
46*4882a593Smuzhiyunmodule. The communication is rather slow, because the serial port has
47*4882a593Smuzhiyunto operate at 1200 bps. However, I don't think this is a big concern in
48*4882a593Smuzhiyunpractice, as these modules are meant for evaluation and testing only.
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