xref: /third_party/ltp/testcases/kernel/device-drivers/acpi/README

- ACPI testcase -
        ACPI must be enabled in the kernel. Since ACPI will control devices and possibly put them to sleep,
        it's not recommended that any other tests be run concurrently with these tests since you may
        get unexpected results.
        These tests are currently ONLY supported on the 2.5 kernels. 2.4 kernels probably won't even build much
        less run.
        run ltpacpi.sh -r run  to execute the tests

3.a. A function "acpi_get_object_info" has been added to the LtpAcpiCmds.c file of LTP project.
        (\ltp\testcases\kernel\device-drivers\acpi\LtpAcpiCmds.c)
         This function returns information about an object as seen from the namespace node.

3.b. A function "acpi_install_fixed_event_handler" has been added to the LtpAcpiCmds.c file of LTP project.
        This function saves the pointer to the handler function and then enables the event.

3.c. A function "acpi_remove_fixed_event_handler" has been added to the LtpAcpiCmds.c file.
        Disables the event and unregisters the event handler.

3.d. A function "acpi_acquire_global_lock" has been added to LtpAcpiCmds.c file.
        Acquire the ACPI Global Lock

3.e. A function "acpi_release_global_lock" has been added to LtpAcpiCmds.c file.
        Release the ACPI Global Lock

3.f. A function "acpi_bus_find_driver" has been added to LtpAcpiCmds.c file.
        Parses the list of registered drivers looking for a driver applicable for the specified device.

3.g. A function "acpi_bus_get_power" has been added to LtpAcpiCmds.c file.
        Get the device's power state either directly (via _PSC) or indirectly (via power resources).

3.h. A function "acpi_evaluate_integer" has been added to LtpAcpiCmds.c file.
        Looks for _GPE object (an integer). If _GPE evaluates to an integer,
the value is the bit assignment of the SCI interrupt within the GPEx_STS register of a GPE
block described in the FADT that the embedded controller will trigger.

4. Including ACPI support into the kernel

 By default, the kernel may not enable ACPI feature. A kernel configuration option must be selected
 to enable ACPI support.

5. FAQ

Q.5.1. Are there any limitations on using this patch?

A.5.1. If the device supports ACPI feature and the ACPI feature is enabled in the kernel,
then only a user will be able to use these scripts.