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Diffstat (limited to 'include/linux/greybus/operation.h')
| -rw-r--r-- | include/linux/greybus/operation.h | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/include/linux/greybus/operation.h b/include/linux/greybus/operation.h new file mode 100644 index 000000000000..cb8e4ef45222 --- /dev/null +++ b/include/linux/greybus/operation.h @@ -0,0 +1,229 @@ +/* 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 */ |