nsxfeval.c

linux-2.6.15.6

 *              Context             - Passed to user function
 *              return_value        - Location where return value of
 *                                    user_function is put if terminated early
 *
 * RETURNS      Return value from the user_function if terminated early.
 *              Otherwise, returns NULL.
 *
 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 *              starting (and ending) at the object specified by start_handle.
 *              The user_function is called whenever an object that matches
 *              the type parameter is found.  If the user function returns
 *              a non-zero value, the search is terminated immediately and this
 *              value is returned to the caller.
 *
 *              The point of this procedure is to provide a generic namespace
 *              walk routine that can be called from multiple places to
 *              provide multiple services;  the User Function can be tailored
 *              to each task, whether it is a print function, a compare
 *              function, etc.
 *
 ******************************************************************************/

acpi_status
acpi_walk_namespace(acpi_object_type type,
		    acpi_handle start_object,
		    u32 max_depth,
		    acpi_walk_callback user_function,
		    void *context, void **return_value)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE("acpi_walk_namespace");

	/* Parameter validation */

	if ((type > ACPI_TYPE_EXTERNAL_MAX) || (!max_depth) || (!user_function)) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/*
	 * Lock the namespace around the walk.
	 * The namespace will be unlocked/locked around each call
	 * to the user function - since this function
	 * must be allowed to make Acpi calls itself.
	 */
	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_ns_walk_namespace(type, start_object, max_depth,
					ACPI_NS_WALK_UNLOCK,
					user_function, context, return_value);

	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return_ACPI_STATUS(status);
}

EXPORT_SYMBOL(acpi_walk_namespace);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_device_callback
 *
 * PARAMETERS:  Callback from acpi_get_device
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
 *              present devices, or if they specified a HID, it filters based
 *              on that.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_get_device_callback(acpi_handle obj_handle,
			    u32 nesting_level,
			    void *context, void **return_value)
{
	struct acpi_get_devices_info *info = context;
	acpi_status status;
	struct acpi_namespace_node *node;
	u32 flags;
	struct acpi_device_id hid;
	struct acpi_compatible_id_list *cid;
	acpi_native_uint i;

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	node = acpi_ns_map_handle_to_node(obj_handle);
	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	if (!node) {
		return (AE_BAD_PARAMETER);
	}

	/* Run _STA to determine if device is present */

	status = acpi_ut_execute_STA(node, &flags);
	if (ACPI_FAILURE(status)) {
		return (AE_CTRL_DEPTH);
	}

	if (!(flags & 0x01)) {
		/* Don't return at the device or children of the device if not there */

		return (AE_CTRL_DEPTH);
	}

	/* Filter based on device HID & CID */

	if (info->hid != NULL) {
		status = acpi_ut_execute_HID(node, &hid);
		if (status == AE_NOT_FOUND) {
			return (AE_OK);
		} else if (ACPI_FAILURE(status)) {
			return (AE_CTRL_DEPTH);
		}

		if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
			/* Get the list of Compatible IDs */

			status = acpi_ut_execute_CID(node, &cid);
			if (status == AE_NOT_FOUND) {
				return (AE_OK);
			} else if (ACPI_FAILURE(status)) {
				return (AE_CTRL_DEPTH);
			}

			/* Walk the CID list */

			for (i = 0; i < cid->count; i++) {
				if (ACPI_STRNCMP(cid->id[i].value, info->hid,
						 sizeof(struct
							acpi_compatible_id)) !=
				    0) {
					ACPI_MEM_FREE(cid);
					return (AE_OK);
				}
			}
			ACPI_MEM_FREE(cid);
		}
	}

	status = info->user_function(obj_handle, nesting_level, info->context,
				     return_value);
	return (status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_devices
 *
 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
 *              user_function       - Called when a matching object is found
 *              Context             - Passed to user function
 *              return_value        - Location where return value of
 *                                    user_function is put if terminated early
 *
 * RETURNS      Return value from the user_function if terminated early.
 *              Otherwise, returns NULL.
 *
 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 *              starting (and ending) at the object specified by start_handle.
 *              The user_function is called whenever an object of type
 *              Device is found.  If the user function returns
 *              a non-zero value, the search is terminated immediately and this
 *              value is returned to the caller.
 *
 *              This is a wrapper for walk_namespace, but the callback performs
 *              additional filtering. Please see acpi_get_device_callback.
 *
 ******************************************************************************/

acpi_status
acpi_get_devices(char *HID,
		 acpi_walk_callback user_function,
		 void *context, void **return_value)
{
	acpi_status status;
	struct acpi_get_devices_info info;

	ACPI_FUNCTION_TRACE("acpi_get_devices");

	/* Parameter validation */

	if (!user_function) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/*
	 * We're going to call their callback from OUR callback, so we need
	 * to know what it is, and their context parameter.
	 */
	info.context = context;
	info.user_function = user_function;
	info.hid = HID;

	/*
	 * Lock the namespace around the walk.
	 * The namespace will be unlocked/locked around each call
	 * to the user function - since this function
	 * must be allowed to make Acpi calls itself.
	 */
	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE,
					ACPI_ROOT_OBJECT, ACPI_UINT32_MAX,
					ACPI_NS_WALK_UNLOCK,
					acpi_ns_get_device_callback, &info,
					return_value);

	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return_ACPI_STATUS(status);
}

EXPORT_SYMBOL(acpi_get_devices);

/*******************************************************************************
 *
 * FUNCTION:    acpi_attach_data
 *
 * PARAMETERS:  obj_handle          - Namespace node
 *              Handler             - Handler for this attachment
 *              Data                - Pointer to data to be attached
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
 *
 ******************************************************************************/

acpi_status
acpi_attach_data(acpi_handle obj_handle,
		 acpi_object_handler handler, void *data)
{
	struct acpi_namespace_node *node;
	acpi_status status;

	/* Parameter validation */

	if (!obj_handle || !handler || !data) {
		return (AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Convert and validate the handle */

	node = acpi_ns_map_handle_to_node(obj_handle);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	status = acpi_ns_attach_data(node, handler, data);

      unlock_and_exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return (status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_detach_data
 *
 * PARAMETERS:  obj_handle          - Namespace node handle
 *              Handler             - Handler used in call to acpi_attach_data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Remove data that was previously attached to a node.
 *
 ******************************************************************************/

acpi_status
acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
{
	struct acpi_namespace_node *node;
	acpi_status status;

	/* Parameter validation */

	if (!obj_handle || !handler) {
		return (AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Convert and validate the handle */

	node = acpi_ns_map_handle_to_node(obj_handle);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	status = acpi_ns_detach_data(node, handler);

      unlock_and_exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return (status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_data
 *
 * PARAMETERS:  obj_handle          - Namespace node
 *              Handler             - Handler used in call to attach_data
 *              Data                - Where the data is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 *
 ******************************************************************************/

acpi_status
acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
{
	struct acpi_namespace_node *node;
	acpi_status status;

	/* Parameter validation */

	if (!obj_handle || !handler || !data) {
		return (AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Convert and validate the handle */

	node = acpi_ns_map_handle_to_node(obj_handle);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	status = acpi_ns_get_attached_data(node, handler, data);

      unlock_and_exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return (status);
}