diff options
| -rw-r--r-- | Documentation/i2c/slave-testunit-backend.rst | 14 | ||||
| -rw-r--r-- | drivers/i2c/i2c-slave-testunit.c | 4 |
2 files changed, 10 insertions, 8 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 diff --git a/drivers/i2c/i2c-slave-testunit.c b/drivers/i2c/i2c-slave-testunit.c index 51b399aa09a0..04060bc8a9d0 100644 --- a/drivers/i2c/i2c-slave-testunit.c +++ b/drivers/i2c/i2c-slave-testunit.c @@ -15,7 +15,6 @@ #include <linux/slab.h> #include <linux/workqueue.h> /* FIXME: is system_long_wq the best choice? */ -#define TU_CUR_VERSION 0x01 #define TU_VERSION_MAX_LENGTH 128 enum testunit_cmds { @@ -159,7 +158,8 @@ static int i2c_slave_testunit_slave_cb(struct i2c_client *client, else if (is_proc_call) *val = tu->regs[TU_REG_DATAH]; else - *val = TU_CUR_VERSION; + *val = test_bit(TU_FLAG_IN_PROCESS, &tu->flags) ? + tu->regs[TU_REG_CMD] : 0; break; } |