nsxfobj.c

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

	/* Get the parent entry */

	*ret_handle =
		acpi_ns_convert_entry_to_handle (acpi_ns_get_parent_node (node));

	/* Return exeption if parent is null */

	if (!acpi_ns_get_parent_node (node)) {
		status = AE_NULL_ENTRY;
	}


unlock_and_exit:

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


/*******************************************************************************
 *
 * FUNCTION:    Acpi_walk_namespace
 *
 * PARAMETERS:  Type                - acpi_object_type to search for
 *              Start_object        - Handle in namespace where search begins
 *              Max_depth           - Depth to which search is to reach
 *              User_function       - Called when an object of "Type" 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 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_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);
}


/*******************************************************************************
 *
 * 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)
{
	acpi_status             status;
	acpi_namespace_node     *node;
	u32                     flags;
	acpi_device_id          hid;
	acpi_device_id          cid;
	acpi_get_devices_info   *info;


	info = context;

	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.buffer, info->hid, sizeof (hid.buffer)) != 0) {
			status = acpi_ut_execute_CID (node, &cid);
			if (status == AE_NOT_FOUND) {
				return (AE_OK);
			}
			else if (ACPI_FAILURE (status)) {
				return (AE_CTRL_DEPTH);
			}

			/* TBD: Handle CID packages */

			if (ACPI_STRNCMP (cid.buffer, info->hid, sizeof (cid.buffer)) != 0) {
				return (AE_OK);
			}
		}
	}

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


/*******************************************************************************
 *
 * 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 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.
 *
 *              This is a wrapper for Walk_namespace, but the callback performs
 *              additional filtering. Please see Acpi_get_device_callback.
 *
 ******************************************************************************/

acpi_status
acpi_get_devices (
	NATIVE_CHAR             *HID,
	acpi_walk_callback      user_function,
	void                    *context,
	void                    **return_value)
{
	acpi_status             status;
	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);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_attach_data
 *
 * PARAMETERS:
 *
 * RETURN:      Status
 *
 * DESCRIPTION:
 *
 ******************************************************************************/

acpi_status
acpi_attach_data (
	acpi_handle             obj_handle,
	ACPI_OBJECT_HANDLER     handler,
	void                    *data)
{
	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:
 *
 * RETURN:      Status
 *
 * DESCRIPTION:
 *
 ******************************************************************************/

acpi_status
acpi_detach_data (
	acpi_handle             obj_handle,
	ACPI_OBJECT_HANDLER     handler)
{
	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:
 *
 * RETURN:      Status
 *
 * DESCRIPTION:
 *
 ******************************************************************************/

acpi_status
acpi_get_data (
	acpi_handle             obj_handle,
	ACPI_OBJECT_HANDLER     handler,
	void                    **data)
{
	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);
}