Leveraging Regmap from the user space
Register maps can be monitored from the user space via the debugfs file system. First, debugfs needs to be enabled via the CONFIG_DEBUG_FS
kernel configuration option. Then, debugfs can be mounted using the following command:
mount -t debugfs none /sys/kernel/debug
After that, the debugfs register map implementation can be found under /sys/kernel/debug/regmap/
. This debugfs view implemented by drivers/base/regmap/regmap-debugfs.c
in kernel sources contains a register cache (mirror) for drivers/peripherals based on the Regmap API.
From the Regmap main debugfs directory, we can get the list of devices whose drivers are based on the Regmap API using the following command:
root@jetson-nano-devkit:~# ls -l /sys/kernel/debug/regmap/ drwxr-xr-x 2 root root 0 Jan 1 1970 4-003c-power-slave drwxr-xr-x 2 root root 0 Jan 1...