/* * Greybus operations * * Copyright 2014 Google Inc. * Copyright 2014 Linaro Ltd. * * Released under the GPLv2 only. */ #ifndef __OPERATION_H #define __OPERATION_H #include 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 */ }; 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); } int gb_operation_init(void); void gb_operation_exit(void); #endif /* !__OPERATION_H */