1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Basic framing protocol for STM devices.
4 * Copyright (c) 2018, Intel Corporation.
5 */
6
7#include <linux/module.h>
8#include <linux/device.h>
9#include <linux/stm.h>
10#include "stm.h"
11
12static ssize_t basic_write(struct stm_data *data, struct stm_output *output,
13 unsigned int chan, const char *buf, size_t count)
14{
15 unsigned int c = output->channel + chan;
16 unsigned int m = output->master;
17 const unsigned char nil = 0;
18 ssize_t sz;
19
20 sz = stm_data_write(data, m, c, ts_first: true, buf, count);
21 if (sz > 0)
22 data->packet(data, m, c, STP_PACKET_FLAG, 0, 0, &nil);
23
24 return sz;
25}
26
27static const struct stm_protocol_driver basic_pdrv = {
28 .owner = THIS_MODULE,
29 .name = "p_basic",
30 .write = basic_write,
31};
32
33static int basic_stm_init(void)
34{
35 return stm_register_protocol(pdrv: &basic_pdrv);
36}
37
38static void basic_stm_exit(void)
39{
40 stm_unregister_protocol(pdrv: &basic_pdrv);
41}
42
43module_init(basic_stm_init);
44module_exit(basic_stm_exit);
45
46MODULE_LICENSE("GPL v2");
47MODULE_DESCRIPTION("Basic STM framing protocol driver");
48MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
49

source code of linux/drivers/hwtracing/stm/p_basic.c