projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| b9cdad74 JD |
1 | Kernel driver i2c-taos-evm |
| 2 | ||
| 3 | Author: Jean Delvare <khali@linux-fr.org> | |
| 4 | ||
| 5 | This is a driver for the evaluation modules for TAOS I2C/SMBus chips. | |
| 6 | The modules include an SMBus master with limited capabilities, which can | |
| 7 | be controlled over the serial port. Virtually all evaluation modules | |
| 8 | are supported, but a few lines of code need to be added for each new | |
| 9 | module to instantiate the right I2C chip on the bus. Obviously, a driver | |
| 10 | for the chip in question is also needed. | |
| 11 | ||
| 12 | Currently supported devices are: | |
| 13 | ||
| 14 | * TAOS TSL2550 EVM | |
| 15 | ||
| 25985edc | 16 | For additional information on TAOS products, please see |
| b9cdad74 JD |
17 | http://www.taosinc.com/ |
| 18 | ||
| 19 | ||
| 20 | Using this driver | |
| 21 | ----------------- | |
| 22 | ||
| 23 | In order to use this driver, you'll need the serport driver, and the | |
| 24 | inputattach tool, which is part of the input-utils package. The following | |
| 25 | commands will tell the kernel that you have a TAOS EVM on the first | |
| 26 | serial port: | |
| 27 | ||
| 28 | # modprobe serport | |
| 29 | # inputattach --taos-evm /dev/ttyS0 | |
| 30 | ||
| 31 | ||
| 32 | Technical details | |
| 33 | ----------------- | |
| 34 | ||
| 35 | Only 4 SMBus transaction types are supported by the TAOS evaluation | |
| 36 | modules: | |
| 37 | * Receive Byte | |
| 38 | * Send Byte | |
| 39 | * Read Byte | |
| 40 | * Write Byte | |
| 41 | ||
| 42 | The communication protocol is text-based and pretty simple. It is | |
| 43 | described in a PDF document on the CD which comes with the evaluation | |
| 44 | module. The communication is rather slow, because the serial port has | |
| 45 | to operate at 1200 bps. However, I don't think this is a big concern in | |
| 46 | practice, as these modules are meant for evaluation and testing only. |