greybus: control: implement mode-switch operation

Implement the unidirectional mode-switch operation.

This operation will be used in the implementation of the new generic
mode-switch functionality.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/control.c

@@ -149,6 +149,13 @@ int gb_control_disconnected_operation(struct gb_control *control, u16 cport_id)
 				 sizeof(request), NULL, 0);
 }
 
+int gb_control_mode_switch_operation(struct gb_control *control)
+{
+	return gb_operation_unidirectional(control->connection,
+						GB_CONTROL_TYPE_MODE_SWITCH,
+						NULL, 0);
+}
+
 int gb_control_get_interface_version_operation(struct gb_interface *intf)
 {
 	struct gb_control_interface_version_response response;

drivers/staging/greybus/control.h

@@ -36,6 +36,7 @@ void gb_control_put(struct gb_control *control);
 int gb_control_get_bundle_versions(struct gb_control *control);
 int gb_control_connected_operation(struct gb_control *control, u16 cport_id);
 int gb_control_disconnected_operation(struct gb_control *control, u16 cport_id);
+int gb_control_mode_switch_operation(struct gb_control *control);
 int gb_control_get_manifest_size_operation(struct gb_interface *intf);
 int gb_control_get_manifest_operation(struct gb_interface *intf, void *manifest,
 				      size_t size);

drivers/staging/greybus/greybus_protocols.h

@@ -123,6 +123,7 @@ struct gb_protocol_version_response {
 #define GB_CONTROL_TYPE_TIMESYNC_AUTHORITATIVE	0x09
 #define GB_CONTROL_TYPE_INTERFACE_VERSION	0x0a
 #define GB_CONTROL_TYPE_BUNDLE_VERSION		0x0b
+#define GB_CONTROL_TYPE_MODE_SWITCH		0x0e
 
 struct gb_control_version_request {
 	__u8	major;