zephyr/include/ec_host_cmd.h

208 lines
7.3 KiB
C

/*
* Copyright (c) 2020 Google LLC
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_INCLUDE_EC_HOST_CMD_H_
#define ZEPHYR_INCLUDE_EC_HOST_CMD_H_
/**
* @brief EC Host Command Interface
* @defgroup ec_host_cmd_periph_interface EC Host Command Interface
* @ingroup io_interfaces
* @{
*/
#include <stdint.h>
/**
* @brief Arguments passed into every installed host command handler
*/
struct ec_host_cmd_handler_args {
/** The incoming data that can be cast to the handlers request type. */
const void *const input_buf;
/** The number of valid bytes that can be read from @a input_buf. */
const uint16_t input_buf_size;
/** The data written to this buffer will be send to the host. */
void *const output_buf;
/** [in/out] Upon entry, this is the maximum number of bytes that can
* be written to the @a output_buf. Upon exit, this should be
* the number of bytes of @a output_buf to send to the host.
*/
uint16_t output_buf_size;
/** The version of the host command that is being requested. This will
* be a value that has been static registered as valid for the handler.
*/
const uint8_t version;
};
typedef enum ec_host_cmd_status (*ec_host_cmd_handler_cb)(
struct ec_host_cmd_handler_args *args);
/**
* @brief Structure use for statically registering host command handlers
*/
struct ec_host_cmd_handler {
/** Callback routine to process commands that match @a id. */
ec_host_cmd_handler_cb handler;
/** The numberical command id used as the lookup for commands. */
uint16_t id;
/** The bitfield of all versions that the @a handler supports, where
* each bit value represents that the @a handler supports that version.
* E.g. BIT(0) corresponse to version 0.
*/
uint16_t version_mask;
/** The minimum @a input_buf_size enforced by the framework before
* passing to the handler.
*/
uint16_t min_rqt_size;
/** The minimum @a output_buf_size enforced by the framework before
* passing to the handler.
*/
uint16_t min_rsp_size;
};
/**
* @def EC_HOST_CMD_HANDLER
* @brief Statically define and register a host command handler.
*
* Helper macro to statically define and register a host command handler that
* has a compile-time-fixed sizes for its both request and response structures.
*
* @param _function Name of handler function.
* @param _id Id of host command to handle request for.
* @param _version_mask The bitfield of all versions that the @a _function
* supports. E.g. BIT(0) corresponse to version 0.
* @param _request_type The datatype of the request parameters for @a _function.
* @param _response_type The datatype of the response parameters for
* @a _function.
*/
#define EC_HOST_CMD_HANDLER(_function, _id, _version_mask, _request_type, \
_response_type) \
const Z_STRUCT_SECTION_ITERABLE(ec_host_cmd_handler, __cmd##_id) = { \
.id = _id, \
.handler = _function, \
.version_mask = _version_mask, \
.min_rqt_size = sizeof(_request_type), \
.min_rsp_size = sizeof(_response_type), \
}
/**
* @def EC_HOST_CMD_HANDLER_UNBOUND
* @brief Statically define and register a host command handler without sizes.
*
* Helper macro to statically define and register a host command handler whose
* request or response structure size is not known as compile time.
*
* @param _function Name of handler function.
* @param _id Id of host command to handle request for.
* @param _version_mask The bitfield of all versions that the @a _function
* supports. E.g. BIT(0) corresponse to version 0.
*/
#define EC_HOST_CMD_HANDLER_UNBOUND(_function, _id, _version_mask) \
const Z_STRUCT_SECTION_ITERABLE(ec_host_cmd_handler, __cmd##_id) = { \
.id = _id, \
.handler = _function, \
.version_mask = _version_mask, \
.min_rqt_size = 0, \
.min_rsp_size = 0, \
}
/**
* @brief Header for requests from host to embedded controller
*
* Represent the over-the-wire header in LE format for host command requests.
* This represent version 3 of the host command header. The requests are always
* sent from host to embedded controller.
*/
struct ec_host_cmd_request_header {
/** Should be 3. The EC will return EC_HOST_CMD_INVALID_HEADER if it
* receives a header with a version it doesn't know how to parse.
*/
uint8_t prtcl_ver;
/** Checksum of response and data; sum of all bytes including checksum.
* Should total to 0.
*/
uint8_t checksum;
/** Id of command that is being sent. */
uint16_t cmd_id;
/** Version of the specific @a cmd_id being requested. Valid
* versions start at 0.
*/
uint8_t cmd_ver;
/** Unused byte in current protocol version; set to 0. */
uint8_t reserved;
/** Length of data which follows this header. */
uint16_t data_len;
} __packed;
/**
* @brief Header for responses from embedded controller to host
*
* Represent the over-the-wire header in LE format for host command responses.
* This represent version 3 of the host command header. Responses are always
* sent from embedded controller to host.
*/
struct ec_host_cmd_response_header {
/** Should be 3. */
uint8_t prtcl_ver;
/** Checksum of response and data; sum of all bytes including checksum.
* Should total to 0.
*/
uint8_t checksum;
/** A @a ec_host_cmd_status response code for specific command. */
uint16_t result;
/** Length of data which follows this header. */
uint16_t data_len;
/** Unused bytes in current protocol version; set to 0. */
uint16_t reserved;
} __packed;
/*
* Host command response codes (16-bit).
*/
enum ec_host_cmd_status {
/** Host command was successful. */
EC_HOST_CMD_SUCCESS = 0,
/** The specified command id is not recognized or supported. */
EC_HOST_CMD_INVALID_COMMAND = 1,
/** Generic Error. */
EC_HOST_CMD_ERROR = 2,
/** One of more of the input request parameters is invalid. */
EC_HOST_CMD_INVALID_PARAM = 3,
/** Host command is not permitted. */
EC_HOST_CMD_ACCESS_DENIED = 4,
/** Response was invalid (e.g. not version 3 of header). */
EC_HOST_CMD_INVALID_RESPONSE = 5,
/** Host command id version unsupported. */
EC_HOST_CMD_INVALID_VERSION = 6,
/** Checksum did not match */
EC_HOST_CMD_INVALID_CHECKSUM = 7,
/** A host command is currently being processed. */
EC_HOST_CMD_IN_PROGRESS = 8,
/** Requested information is currently unavailable. */
EC_HOST_CMD_UNAVAILABLE = 9,
/** Timeout during processing. */
EC_HOST_CMD_TIMEOUT = 10,
/** Data or table overflow. */
EC_HOST_CMD_OVERFLOW = 11,
/** Header is invalid or unsupported (e.g. not version 3 of header). */
EC_HOST_CMD_INVALID_HEADER = 12,
/** Did not receive all expected request data. */
EC_HOST_CMD_REQUEST_TRUNCATED = 13,
/** Response was too big to send within one response packet. */
EC_HOST_CMD_RESPONSE_TOO_BIG = 14,
/** Error on underlying communication bus. */
EC_HOST_CMD_BUS_ERROR = 15,
/** System busy. Should retry later. */
EC_HOST_CMD_BUSY = 16,
EC_HOST_CMD_MAX = UINT16_MAX /* Force enum to be 16 bits */
} __packed;
/**
* @}
*/
#endif /* ZEPHYR_INCLUDE_EC_HOST_CMD_H_ */