EC Dumper

I've written a simple kernel module that dumps the contents of the embedded controller. This module registers a procfs handle which, in turn outputs the content of the ec memory. A brief warning, though. I have experienced infrequent keyboard lockups after heavy usage.

So without further ado:

/*
* ec_dump.c - Dumps the contents of the embedded controller,
* useful for reverse-engineering backlight, killswitches etc.
*
*
* Copyright (C) 2007 Erik Andrén
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/

#include
#include
#include
#include

#include
#include

int ecdump_read_procmem(char *page, char **start, off_t offset, int count, int *eof, void *data)
{
int i, len = 0;
u8 v;
len += sprintf(page + len, "EC +00 +01 +02 +03 +04 +05 +06 +07 +08 +09 +0a +0b +0c +0d +0e +0f\n");
len += sprintf(page + len, "EC 0x%02x: ", 0);
for (i = 0; i < 256; i++) {
if (!ec_read(i, &v))
if (!v)
len += sprintf(page + len, " ");
else
len += sprintf(page + len, "0x%02x ", v);
else
len += sprintf(page + len, "Failed to read address %d!\n", i);

if (i == 255)
break;

if (i % 16 == 15)
len += sprintf(page + len, "\nEC 0x%02x: ", i);
}
len += sprintf(page + len, "\n");
return len;
}

static int __init ec_dump_init(void)
{
printk ("Loading ec_dump!\n");
create_proc_read_entry("ec_dump", 0, NULL, ecdump_read_procmem, NULL);
return 0;
}

static void __exit ec_dump_exit(void)
{
printk ("Unloading my module.\n");
remove_proc_entry("ec_dump", NULL);
return;
}

module_init(ec_dump_init);
module_exit(ec_dump_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Erik Andrén (erik.andren@gmail.com)");


Tags: Linux, ACPI, EC, kernel module, GPL