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author | Vadim Bendebury <vbendeb@chromium.org> | 2015-11-12 16:44:46 -0800 |
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committer | chrome-bot <chrome-bot@chromium.org> | 2015-11-17 14:40:26 -0800 |
commit | a8f2e3625e34b51da381236a14a7d28adc37df4a (patch) | |
tree | 6965c1b45350c11d61bbf560fa0a01162b2de119 /include/extension.h | |
parent | 2d57e6f6d98a06abd55e193b6f5d193280f01988 (diff) | |
download | chrome-ec-a8f2e3625e34b51da381236a14a7d28adc37df4a.tar.gz |
add the 'extension' command framework
This patch introduces a facility which would allow to compile in
callbacks for arbitrary commands passed over various communication
protocols.
Typically this will be used for testing, when various test commands
are multiplexed over an existing protocol.
The callbacks are associated with 16 bit command codes. On input the
callback receives a buffer, containing the command's argument, the
size of the command argument and the maximum size of the buffer. On
output the callback stores processing result in the same buffer and
updates the size to the actual amount of returned data.
Callback descriptors are stored in a dedicated read only section which
is scanned by extension_route_command() to find a callback associated
with a certain command code.
A console channel is also being introduced to allow controlling
console output generated by extension commands handlers.
BRANCH=none
BUG=chrome-os-partner:47524
TEST=none yet
Change-Id: I8ae16a78ca7d72176a5e7f74dd7a232078e7c06c
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/312586
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Diffstat (limited to 'include/extension.h')
-rw-r--r-- | include/extension.h | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/include/extension.h b/include/extension.h new file mode 100644 index 0000000000..45637d9518 --- /dev/null +++ b/include/extension.h @@ -0,0 +1,56 @@ +/* Copyright 2015 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#ifndef __EC_INCLUDE_EXTENSION_H +#define __EC_INCLUDE_EXTENSION_H + +#include <stddef.h> +#include <stdint.h> + +#include "common.h" + +/* + * Type of function handling extension commands. + * + * @param buffer As input points to the input data to be processed, as + * output stores data, processing result. + * @param command_size Number of bytes of input data + * @param response_size On input - max size of the buffer, on output - actual + * number of data returned by the handler. + */ +typedef void (*extension_handler)(void *buffer, + size_t command_size, + size_t *response_size); +/* + * Find handler for an extension command. + * + * @param command_code Code associated with a extension command handler. + * @param buffer Data to be processd by the handler, the same space + * is used for data returned by the handler. + * @command_size Size of the input data. + * @param size On input - max size of the buffer, on output - actual + * number of data returned by the handler. + */ +void extension_route_command(uint16_t command_code, + void *buffer, + size_t command_size, + size_t *size); + +struct extension_command { + uint16_t command_code; + extension_handler handler; +} __packed; + +/* Values for different extension commands. */ +enum { + EXTENSION_AES = 0, +}; + +#define DECLARE_EXTENSION_COMMAND(code, handler) \ + const struct extension_command __keep __extension_cmd_##code \ + __attribute__((section(".rodata.extensioncmds"))) \ + = {code, handler} + +#endif /* __EC_INCLUDE_EXTENSION_H */ |