hwtracing/stm/p_basic.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Basic framing protocol for STM devices.
0004  * Copyright (c) 2018, Intel Corporation.
0005  */
0006
0007 #include <linux/module.h>
0008 #include <linux/device.h>
0009 #include <linux/stm.h>
0010 #include "stm.h"
0011
0012 static ssize_t basic_write(struct stm_data *data, struct stm_output *output,
0013                unsigned int chan, const char *buf, size_t count)
0014 {
0015     unsigned int c = output->channel + chan;
0016     unsigned int m = output->master;
0017     const unsigned char nil = 0;
0018     ssize_t sz;
0019
0020     sz = stm_data_write(data, m, c, true, buf, count);
0021     if (sz > 0)
0022         data->packet(data, m, c, STP_PACKET_FLAG, 0, 0, &nil);
0023
0024     return sz;
0025 }
0026
0027 static const struct stm_protocol_driver basic_pdrv = {
0028     .owner  = THIS_MODULE,
0029     .name   = "p_basic",
0030     .write  = basic_write,
0031 };
0032
0033 static int basic_stm_init(void)
0034 {
0035     return stm_register_protocol(&basic_pdrv);
0036 }
0037
0038 static void basic_stm_exit(void)
0039 {
0040     stm_unregister_protocol(&basic_pdrv);
0041 }
0042
0043 module_init(basic_stm_init);
0044 module_exit(basic_stm_exit);
0045
0046 MODULE_LICENSE("GPL v2");
0047 MODULE_DESCRIPTION("Basic STM framing protocol driver");
0048 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");