1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Simple kernel console driver for STM devices
4 * Copyright (c) 2014, Intel Corporation.
5 *
6 * STM console will send kernel messages over STM devices to a trace host.
7 */
8
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/console.h>
12 #include <linux/slab.h>
13 #include <linux/stm.h>
14
15 static int stm_console_link(struct stm_source_data *data);
16 static void stm_console_unlink(struct stm_source_data *data);
17
18 static struct stm_console {
19 struct stm_source_data data;
20 struct console console;
21 } stm_console = {
22 .data = {
23 .name = "console",
24 .nr_chans = 1,
25 .type = STM_USER,
26 .link = stm_console_link,
27 .unlink = stm_console_unlink,
28 },
29 };
30
31 static void
stm_console_write(struct console * con,const char * buf,unsigned len)32 stm_console_write(struct console *con, const char *buf, unsigned len)
33 {
34 struct stm_console *sc = container_of(con, struct stm_console, console);
35
36 stm_source_write(&sc->data, 0, buf, len);
37 }
38
stm_console_link(struct stm_source_data * data)39 static int stm_console_link(struct stm_source_data *data)
40 {
41 struct stm_console *sc = container_of(data, struct stm_console, data);
42
43 strcpy(sc->console.name, "stm_console");
44 sc->console.write = stm_console_write;
45 sc->console.flags = CON_ENABLED | CON_PRINTBUFFER;
46 register_console(&sc->console);
47
48 return 0;
49 }
50
stm_console_unlink(struct stm_source_data * data)51 static void stm_console_unlink(struct stm_source_data *data)
52 {
53 struct stm_console *sc = container_of(data, struct stm_console, data);
54
55 unregister_console(&sc->console);
56 }
57
stm_console_init(void)58 static int stm_console_init(void)
59 {
60 return stm_source_register_device(NULL, &stm_console.data);
61 }
62
stm_console_exit(void)63 static void stm_console_exit(void)
64 {
65 stm_source_unregister_device(&stm_console.data);
66 }
67
68 module_init(stm_console_init);
69 module_exit(stm_console_exit);
70
71 MODULE_LICENSE("GPL v2");
72 MODULE_DESCRIPTION("stm_console driver");
73 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
74