diff options
Diffstat (limited to 'Documentation/i2c/slave-testunit-backend.rst')
| -rw-r--r-- | Documentation/i2c/slave-testunit-backend.rst | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/Documentation/i2c/slave-testunit-backend.rst b/Documentation/i2c/slave-testunit-backend.rst index 110c0055064f..d3ab5944877d 100644 --- a/Documentation/i2c/slave-testunit-backend.rst +++ b/Documentation/i2c/slave-testunit-backend.rst @@ -20,11 +20,13 @@ Instantiating the device is regular. Example for bus 0, address 0x30:: # echo "slave-testunit 0x1030" > /sys/bus/i2c/devices/i2c-0/new_device -After that, you will have a write-only device listening. Reads will just return -an 8-bit version number of the testunit. When writing, the device consists of 4 -8-bit registers and, except for some "partial" commands, all registers must be -written to start a testcase, i.e. you usually write 4 bytes to the device. The -registers are: +After that, you will have the device listening. Reading will return a single +byte. Its value is 0 if the testunit is idle, otherwise the command number of +the currently running command. + +When writing, the device consists of 4 8-bit registers and, except for some +"partial" commands, all registers must be written to start a testcase, i.e. you +usually write 4 bytes to the device. The registers are: .. csv-table:: :header: "Offset", "Name", "Description" @@ -170,4 +172,4 @@ are not equivalent to a REPEATED START. As an example, this returns just the default response:: # i2cset -y 0 0x30 4 0 0 i; i2cget -y 0 0x30 - 0x01 + 0x00 |