linux/include/linux/greybus/operation.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Greybus operations
 *
 * Copyright 2014 Google Inc.
 * Copyright 2014 Linaro Ltd.
 */

#ifndef __OPERATION_H
#define __OPERATION_H

#include <linux/completion.h>
#include <linux/kref.h>
#include <linux/timer.h>
#include <linux/types.h>
#include <linux/workqueue.h>

struct gb_host_device;
struct gb_operation;

/* The default amount of time a request is given to complete */
#define GB_OPERATION_TIMEOUT_DEFAULT …

/*
 * The top bit of the type in an operation message header indicates
 * whether the message is a request (bit clear) or response (bit set)
 */
#define GB_MESSAGE_TYPE_RESPONSE …

enum gb_operation_result { … };

#define GB_OPERATION_MESSAGE_SIZE_MIN …
#define GB_OPERATION_MESSAGE_SIZE_MAX …

/*
 * Protocol code should only examine the payload and payload_size fields, and
 * host-controller drivers may use the hcpriv field. All other fields are
 * intended to be private to the operations core code.
 */
struct gb_message { … };

#define GB_OPERATION_FLAG_INCOMING …
#define GB_OPERATION_FLAG_UNIDIRECTIONAL …
#define GB_OPERATION_FLAG_SHORT_RESPONSE …
#define GB_OPERATION_FLAG_CORE …

#define GB_OPERATION_FLAG_USER_MASK …

/*
 * A Greybus operation is a remote procedure call performed over a
 * connection between two UniPro interfaces.
 *
 * Every operation consists of a request message sent to the other
 * end of the connection coupled with a reply message returned to
 * the sender.  Every operation has a type, whose interpretation is
 * dependent on the protocol associated with the connection.
 *
 * Only four things in an operation structure are intended to be
 * directly usable by protocol handlers:  the operation's connection
 * pointer; the operation type; the request message payload (and
 * size); and the response message payload (and size).  Note that a
 * message with a 0-byte payload has a null message payload pointer.
 *
 * In addition, every operation has a result, which is an errno
 * value.  Protocol handlers access the operation result using
 * gb_operation_result().
 */
gb_operation_callback;
struct gb_operation { … };

static inline bool
gb_operation_is_incoming(struct gb_operation *operation)
{ … }

static inline bool
gb_operation_is_unidirectional(struct gb_operation *operation)
{ … }

static inline bool
gb_operation_short_response_allowed(struct gb_operation *operation)
{ … }

static inline bool gb_operation_is_core(struct gb_operation *operation)
{ … }

void gb_connection_recv(struct gb_connection *connection,
					void *data, size_t size);

int gb_operation_result(struct gb_operation *operation);

size_t gb_operation_get_payload_size_max(struct gb_connection *connection);
struct gb_operation *
gb_operation_create_flags(struct gb_connection *connection,
				u8 type, size_t request_size,
				size_t response_size, unsigned long flags,
				gfp_t gfp);

static inline struct gb_operation *
gb_operation_create(struct gb_connection *connection,
				u8 type, size_t request_size,
				size_t response_size, gfp_t 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);

bool gb_operation_response_alloc(struct gb_operation *operation,
					size_t response_size, gfp_t gfp);

int gb_operation_request_send(struct gb_operation *operation,
				gb_operation_callback callback,
				unsigned int timeout,
				gfp_t gfp);
int gb_operation_request_send_sync_timeout(struct gb_operation *operation,
						unsigned int timeout);
static inline int
gb_operation_request_send_sync(struct gb_operation *operation)
{ … }

void gb_operation_cancel(struct gb_operation *operation, int errno);
void gb_operation_cancel_incoming(struct gb_operation *operation, int errno);

void greybus_message_sent(struct gb_host_device *hd,
				struct gb_message *message, int status);

int gb_operation_sync_timeout(struct gb_connection *connection, int type,
				void *request, int request_size,
				void *response, int response_size,
				unsigned int timeout);
int gb_operation_unidirectional_timeout(struct gb_connection *connection,
				int type, void *request, int request_size,
				unsigned int timeout);

static inline int gb_operation_sync(struct gb_connection *connection, int type,
		      void *request, int request_size,
		      void *response, int response_size)
{ … }

static inline int gb_operation_unidirectional(struct gb_connection *connection,
				int type, void *request, int request_size)
{ … }

static inline void *gb_operation_get_data(struct gb_operation *operation)
{ … }

static inline void gb_operation_set_data(struct gb_operation *operation,
					 void *data)
{ … }

int gb_operation_init(void);
void gb_operation_exit(void);

#endif /* !__OPERATION_H */