greybus: operation: add helper for creating core operations

Add a new core operation flag and a helper that core can use to create
core operations.

This will be used to implement the ping operations that core sends as
part of connection tear down.

Note that a new trace point is also added.

Signed-off-by: Johan Hovold <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/greybus/greybus_trace.h

···
 DEFINE_OPERATION_EVENT(gb_operation_create);
 
 /*
+ * Occurs after a new core operation has been created.
+ */
+DEFINE_OPERATION_EVENT(gb_operation_create_core);
+
+/*
  * Occurs after a new operation has been created for an incoming
  * request has been successfully created and initialized.
  */

drivers/staging/greybus/operation.c

···
 }
 EXPORT_SYMBOL_GPL(gb_operation_create_flags);
 
+struct gb_operation *
+gb_operation_create_core(struct gb_connection *connection,
+				u8 type, size_t request_size,
+				size_t response_size, unsigned long flags,
+				gfp_t gfp)
+{
+	struct gb_operation *operation;
+
+	flags |= GB_OPERATION_FLAG_CORE;
+
+	operation = gb_operation_create_common(connection, type,
+						request_size, response_size,
+						flags, gfp);
+	if (operation)
+		trace_gb_operation_create_core(operation);
+
+	return operation;
+}
+/* Do not export this function. */
+
 size_t gb_operation_get_payload_size_max(struct gb_connection *connection)
 {
 	struct gb_host_device *hd = connection->hd;

drivers/staging/greybus/operation.h

···
 #define GB_OPERATION_FLAG_INCOMING		BIT(0)
 #define GB_OPERATION_FLAG_UNIDIRECTIONAL	BIT(1)
 #define GB_OPERATION_FLAG_SHORT_RESPONSE	BIT(2)
+#define GB_OPERATION_FLAG_CORE			BIT(3)
 
 #define GB_OPERATION_FLAG_USER_MASK	(GB_OPERATION_FLAG_SHORT_RESPONSE | \
 					 GB_OPERATION_FLAG_UNIDIRECTIONAL)
···
 	return operation->flags & GB_OPERATION_FLAG_SHORT_RESPONSE;
 }
 
+static inline bool gb_operation_is_core(struct gb_operation *operation)
+{
+	return operation->flags & GB_OPERATION_FLAG_CORE;
+}
+
 void gb_connection_recv(struct gb_connection *connection,
 					void *data, size_t size);
 
···
 	return gb_operation_create_flags(connection, type, request_size,
 						response_size, 0, gfp);
 }
+
+struct gb_operation *
+gb_operation_create_core(struct gb_connection *connection,
+				u8 type, size_t request_size,
+				size_t response_size, unsigned long flags,
+				gfp_t gfp);
 
 void gb_operation_get(struct gb_operation *operation);
 void gb_operation_put(struct gb_operation *operation);