LXR linux/drivers/hwtracing/stm/console.c

   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
  15static int stm_console_link(struct stm_source_data *data);
  16static void stm_console_unlink(struct stm_source_data *data);
  17
  18static 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
  30static void
  31stm_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
  38static 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
  50static 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
  57static int stm_console_init(void)
  58{
  59        return stm_source_register_device(NULL, &stm_console.data);
  60}
  61
  62static void stm_console_exit(void)
  63{
  64        stm_source_unregister_device(&stm_console.data);
  65}
  66
  67module_init(stm_console_init);
  68module_exit(stm_console_exit);
  69
  70MODULE_LICENSE("GPL v2");
  71MODULE_DESCRIPTION("stm_console driver");
  72MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
  73