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 .link = stm_console_link,
26 .unlink = stm_console_unlink,
27 },
28 };
29
30 static void
stm_console_write(struct console * con,const char * buf,unsigned len)31 stm_console_write(struct console *con, const char *buf, unsigned len)
32 {
33 struct stm_console *sc = container_of(con, struct stm_console, console);
34
35 stm_source_write(&sc->data, 0, buf, len);
36 }
37
stm_console_link(struct stm_source_data * data)38 static int stm_console_link(struct stm_source_data *data)
39 {
40 struct stm_console *sc = container_of(data, struct stm_console, data);
41
42 strcpy(sc->console.name, "stm_console");
43 sc->console.write = stm_console_write;
44 sc->console.flags = CON_ENABLED | CON_PRINTBUFFER;
45 register_console(&sc->console);
46
47 return 0;
48 }
49
stm_console_unlink(struct stm_source_data * data)50 static void stm_console_unlink(struct stm_source_data *data)
51 {
52 struct stm_console *sc = container_of(data, struct stm_console, data);
53
54 unregister_console(&sc->console);
55 }
56
stm_console_init(void)57 static int stm_console_init(void)
58 {
59 return stm_source_register_device(NULL, &stm_console.data);
60 }
61
stm_console_exit(void)62 static void stm_console_exit(void)
63 {
64 stm_source_unregister_device(&stm_console.data);
65 }
66
67 module_init(stm_console_init);
68 module_exit(stm_console_exit);
69
70 MODULE_LICENSE("GPL v2");
71 MODULE_DESCRIPTION("stm_console driver");
72 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
73