diff options
Diffstat (limited to 'drivers/acpi/utils.c')
| -rw-r--r-- | drivers/acpi/utils.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c index 57663065dbf6..abac5cc25477 100644 --- a/drivers/acpi/utils.c +++ b/drivers/acpi/utils.c @@ -450,6 +450,40 @@ void acpi_handle_list_free(struct acpi_handle_list *list) } EXPORT_SYMBOL_GPL(acpi_handle_list_free); +/** + * acpi_device_dep - Check ACPI device dependency + * @target: ACPI handle of the target ACPI device. + * @match: ACPI handle to look up in the target's _DEP list. + * + * Return true if @match is present in the list returned by _DEP for + * @target or false otherwise. + */ +bool acpi_device_dep(acpi_handle target, acpi_handle match) +{ + struct acpi_handle_list dep_devices; + bool ret = false; + int i; + + if (!acpi_has_method(target, "_DEP")) + return false; + + if (!acpi_evaluate_reference(target, "_DEP", NULL, &dep_devices)) { + acpi_handle_debug(target, "Failed to evaluate _DEP.\n"); + return false; + } + + for (i = 0; i < dep_devices.count; i++) { + if (dep_devices.handles[i] == match) { + ret = true; + break; + } + } + + acpi_handle_list_free(&dep_devices); + return ret; +} +EXPORT_SYMBOL_GPL(acpi_device_dep); + acpi_status acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld) { |