Testing Installed Devices

To test a single installed device, type:

ok test device-specifier

This executes the device method (named selftest) of the specified device node. Response depends on the self-test of the device node.

To test a group of installed devices, type:

ok test-all 

All devices below the root node of the device tree are tested. The response depends on the devices that have a self-test method. If you use the device-specifier option with the test-all command, all devices below the specified device tree node are tested.