- riptutorial: Tracing i2c events
- As root change to the
/sys/kernel/debug directory
- If it is not mounted you can mount it with this command,
mount -t debugfs none /sys/kernel/debug
- Inside the
debug directory switch to the tracing dir, cd tracing
- Disable any current function tracer,
echo nop > current_tracer
- Enable all i2c events with,
echo 1 > events/i2c/enable
- Ensure tracing is enabled,
echo 1 > tracing_on
- View logs with this,
tail -f /sys/kernel/debug/tracing/trace
irq/138-maxtouc-202 [000] .... 4415.870855: i2c_read: i2c-1 #0 a=04a f=0001 l=2
irq/138-maxtouc-202 [000] .... 4415.871066: i2c_reply: i2c-1 #0 a=04a f=0001 l=2 [01-5e]
irq/138-maxtouc-202 [000] .... 4415.871068: i2c_result: i2c-1 n=1 ret=1
- The above is an example of what the trace logs look like