/* 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 1000 /* milliseconds */
/*
* 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 ((u8)0x80)
enum gb_operation_result {
GB_OP_SUCCESS = 0x00,
GB_OP_INTERRUPTED = 0x01,
GB_OP_TIMEOUT = 0x02,
GB_OP_NO_MEMORY = 0x03,
GB_OP_PROTOCOL_BAD = 0x04,
GB_OP_OVERFLOW = 0x05,
GB_OP_INVALID = 0x06,
GB_OP_RETRY = 0x07,
GB_OP_NONEXISTENT = 0x08,
GB_OP_UNKNOWN_ERROR = 0xfe,
GB_OP_MALFUNCTION = 0xff,
};
#define GB_OPERATION_MESSAGE_SIZE_MIN sizeof(struct gb_operation_msg_hdr)
#define GB_OPERATION_MESSAGE_SIZE_MAX U16_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 {
struct gb_operation *operation;
struct gb_operation_msg_hdr *header;
void *payload;
size_t payload_size;
void *buffer;
void *hcpriv;
};
#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)
/*
* 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().
*/
typedef void (*gb_operation_callback)(struct gb_operation *);
struct gb_operation {
struct gb_connection *connection;
struct gb_message *request;
struct gb_message *response;
unsigned long flags;
u8 type;
u16 id;
int errno; /* Operation result */
struct work_struct work;
gb_operation_callback callback;
struct completion completion;
struct timer_list timer;
struct kref kref;
atomic_t waiters;
int active;
struct list_head links; /* connection->operations */
void *private;
};
static inline bool
gb_operation_is_incoming(struct gb_operation *operation)
{
return operation->flags & GB_OPERATION_FLAG_INCOMING;
}
static inline bool
gb_operation_is_unidirectional(struct gb_operation *operation)
{
return operation->flags & GB_OPERATION_FLAG_UNIDIRECTIONAL;
}
static inline bool
gb_operation_short_response_allowed(struct gb_operation *operation)
{
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);
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)
{
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);
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)
{
return gb_operation_request_send_sync_timeout(operation,
GB_OPERATION_TIMEOUT_DEFAULT);
}
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)
{
return gb_operation_sync_timeout(connection, type,
request, request_size, response, response_size,
GB_OPERATION_TIMEOUT_DEFAULT);
}
static inline int gb_operation_unidirectional(struct gb_connection *connection,
int type, void *request, int request_size)
{
return gb_operation_unidirectional_timeout(connection, type,
request, request_size, GB_OPERATION_TIMEOUT_DEFAULT);
}
static inline void *gb_operation_get_data(struct gb_operation *operation)
{
return operation->private;
}
static inline void gb_operation_set_data(struct gb_operation *operation,
void *data)
{
operation->private = data;
}
int gb_operation_init(void);
void gb_operation_exit(void);
#endif /* !__OPERATION_H */
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