12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later 2b7e04f8cSWim Van Sebroeck /* 3b7e04f8cSWim Van Sebroeck * MixCom Watchdog: A Simple Hardware Watchdog Device 4b7e04f8cSWim Van Sebroeck * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis 5b7e04f8cSWim Van Sebroeck * 6b7e04f8cSWim Van Sebroeck * Author: Gergely Madarasz <gorgo@itc.hu> 7b7e04f8cSWim Van Sebroeck * 8b7e04f8cSWim Van Sebroeck * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu> 9b7e04f8cSWim Van Sebroeck * 10b7e04f8cSWim Van Sebroeck * Version 0.1 (99/04/15): 11b7e04f8cSWim Van Sebroeck * - first version 12b7e04f8cSWim Van Sebroeck * 13b7e04f8cSWim Van Sebroeck * Version 0.2 (99/06/16): 14b7e04f8cSWim Van Sebroeck * - added kernel timer watchdog ping after close 15b7e04f8cSWim Van Sebroeck * since the hardware does not support watchdog shutdown 16b7e04f8cSWim Van Sebroeck * 17b7e04f8cSWim Van Sebroeck * Version 0.3 (99/06/21): 18b7e04f8cSWim Van Sebroeck * - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls 19b7e04f8cSWim Van Sebroeck * 20b7e04f8cSWim Van Sebroeck * Version 0.3.1 (99/06/22): 21b7e04f8cSWim Van Sebroeck * - allow module removal while internal timer is active, 22b7e04f8cSWim Van Sebroeck * print warning about probable reset 23b7e04f8cSWim Van Sebroeck * 24b7e04f8cSWim Van Sebroeck * Version 0.4 (99/11/15): 25b7e04f8cSWim Van Sebroeck * - support for one more type board 26b7e04f8cSWim Van Sebroeck * 27b7e04f8cSWim Van Sebroeck * Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com> 2839309645SAlan Cox * - added nowayout module option to override 2939309645SAlan Cox * CONFIG_WATCHDOG_NOWAYOUT 30b7e04f8cSWim Van Sebroeck * 31b7e04f8cSWim Van Sebroeck * Version 0.6 (2002/04/12): Rob Radez <rob@osinvestor.com> 32b7e04f8cSWim Van Sebroeck * - make mixcomwd_opened unsigned, 33b7e04f8cSWim Van Sebroeck * removed lock_kernel/unlock_kernel from mixcomwd_release, 34b7e04f8cSWim Van Sebroeck * modified ioctl a bit to conform to API 35b7e04f8cSWim Van Sebroeck */ 36b7e04f8cSWim Van Sebroeck 3727c766aaSJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 3827c766aaSJoe Perches 39b7e04f8cSWim Van Sebroeck #define VERSION "0.6" 40b7e04f8cSWim Van Sebroeck #define WATCHDOG_NAME "mixcomwd" 41b7e04f8cSWim Van Sebroeck 42b7e04f8cSWim Van Sebroeck #include <linux/module.h> 43b7e04f8cSWim Van Sebroeck #include <linux/moduleparam.h> 44b7e04f8cSWim Van Sebroeck #include <linux/types.h> 45b7e04f8cSWim Van Sebroeck #include <linux/miscdevice.h> 46b7e04f8cSWim Van Sebroeck #include <linux/ioport.h> 47b7e04f8cSWim Van Sebroeck #include <linux/watchdog.h> 48b7e04f8cSWim Van Sebroeck #include <linux/fs.h> 49b7e04f8cSWim Van Sebroeck #include <linux/reboot.h> 50b7e04f8cSWim Van Sebroeck #include <linux/init.h> 51b7e04f8cSWim Van Sebroeck #include <linux/jiffies.h> 52b7e04f8cSWim Van Sebroeck #include <linux/timer.h> 5339309645SAlan Cox #include <linux/uaccess.h> 5439309645SAlan Cox #include <linux/io.h> 55b7e04f8cSWim Van Sebroeck 56b7e04f8cSWim Van Sebroeck /* 57b7e04f8cSWim Van Sebroeck * We have two types of cards that can be probed: 58b7e04f8cSWim Van Sebroeck * 1) The Mixcom cards: these cards can be found at addresses 59b7e04f8cSWim Van Sebroeck * 0x180, 0x280, 0x380 with an additional offset of 0xc10. 60b7e04f8cSWim Van Sebroeck * (Or 0xd90, 0xe90, 0xf90). 61b7e04f8cSWim Van Sebroeck * 2) The FlashCOM cards: these cards can be set up at 62b7e04f8cSWim Van Sebroeck * 0x300 -> 0x378, in 0x8 jumps with an offset of 0x04. 63b7e04f8cSWim Van Sebroeck * (Or 0x304 -> 0x37c in 0x8 jumps). 64b7e04f8cSWim Van Sebroeck * Each card has it's own ID. 65b7e04f8cSWim Van Sebroeck */ 66b7e04f8cSWim Van Sebroeck #define MIXCOM_ID 0x11 67b7e04f8cSWim Van Sebroeck #define FLASHCOM_ID 0x18 68b7e04f8cSWim Van Sebroeck static struct { 69b7e04f8cSWim Van Sebroeck int ioport; 70b7e04f8cSWim Van Sebroeck int id; 711d131368SBill Pemberton } mixcomwd_io_info[] = { 72b7e04f8cSWim Van Sebroeck /* The Mixcom cards */ 73b7e04f8cSWim Van Sebroeck {0x0d90, MIXCOM_ID}, 74b7e04f8cSWim Van Sebroeck {0x0e90, MIXCOM_ID}, 75b7e04f8cSWim Van Sebroeck {0x0f90, MIXCOM_ID}, 76b7e04f8cSWim Van Sebroeck /* The FlashCOM cards */ 77b7e04f8cSWim Van Sebroeck {0x0304, FLASHCOM_ID}, 78b7e04f8cSWim Van Sebroeck {0x030c, FLASHCOM_ID}, 79b7e04f8cSWim Van Sebroeck {0x0314, FLASHCOM_ID}, 80b7e04f8cSWim Van Sebroeck {0x031c, FLASHCOM_ID}, 81b7e04f8cSWim Van Sebroeck {0x0324, FLASHCOM_ID}, 82b7e04f8cSWim Van Sebroeck {0x032c, FLASHCOM_ID}, 83b7e04f8cSWim Van Sebroeck {0x0334, FLASHCOM_ID}, 84b7e04f8cSWim Van Sebroeck {0x033c, FLASHCOM_ID}, 85b7e04f8cSWim Van Sebroeck {0x0344, FLASHCOM_ID}, 86b7e04f8cSWim Van Sebroeck {0x034c, FLASHCOM_ID}, 87b7e04f8cSWim Van Sebroeck {0x0354, FLASHCOM_ID}, 88b7e04f8cSWim Van Sebroeck {0x035c, FLASHCOM_ID}, 89b7e04f8cSWim Van Sebroeck {0x0364, FLASHCOM_ID}, 90b7e04f8cSWim Van Sebroeck {0x036c, FLASHCOM_ID}, 91b7e04f8cSWim Van Sebroeck {0x0374, FLASHCOM_ID}, 92b7e04f8cSWim Van Sebroeck {0x037c, FLASHCOM_ID}, 93b7e04f8cSWim Van Sebroeck /* The end of the list */ 94b7e04f8cSWim Van Sebroeck {0x0000, 0}, 95b7e04f8cSWim Van Sebroeck }; 96b7e04f8cSWim Van Sebroeck 9724ed960aSKees Cook static void mixcomwd_timerfun(struct timer_list *unused); 98b7e04f8cSWim Van Sebroeck 99b7e04f8cSWim Van Sebroeck static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */ 100b7e04f8cSWim Van Sebroeck 101b7e04f8cSWim Van Sebroeck static int watchdog_port; 102b7e04f8cSWim Van Sebroeck static int mixcomwd_timer_alive; 1031d27e3e2SKees Cook static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun); 104b7e04f8cSWim Van Sebroeck static char expect_close; 105b7e04f8cSWim Van Sebroeck 10686a1e189SWim Van Sebroeck static bool nowayout = WATCHDOG_NOWAYOUT; 10786a1e189SWim Van Sebroeck module_param(nowayout, bool, 0); 10839309645SAlan Cox MODULE_PARM_DESC(nowayout, 10939309645SAlan Cox "Watchdog cannot be stopped once started (default=" 11039309645SAlan Cox __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 111b7e04f8cSWim Van Sebroeck 112b7e04f8cSWim Van Sebroeck static void mixcomwd_ping(void) 113b7e04f8cSWim Van Sebroeck { 114b7e04f8cSWim Van Sebroeck outb_p(55, watchdog_port); 115b7e04f8cSWim Van Sebroeck return; 116b7e04f8cSWim Van Sebroeck } 117b7e04f8cSWim Van Sebroeck 11824ed960aSKees Cook static void mixcomwd_timerfun(struct timer_list *unused) 119b7e04f8cSWim Van Sebroeck { 120b7e04f8cSWim Van Sebroeck mixcomwd_ping(); 121b7e04f8cSWim Van Sebroeck mod_timer(&mixcomwd_timer, jiffies + 5 * HZ); 122b7e04f8cSWim Van Sebroeck } 123b7e04f8cSWim Van Sebroeck 124b7e04f8cSWim Van Sebroeck /* 125b7e04f8cSWim Van Sebroeck * Allow only one person to hold it open 126b7e04f8cSWim Van Sebroeck */ 127b7e04f8cSWim Van Sebroeck 128b7e04f8cSWim Van Sebroeck static int mixcomwd_open(struct inode *inode, struct file *file) 129b7e04f8cSWim Van Sebroeck { 13039309645SAlan Cox if (test_and_set_bit(0, &mixcomwd_opened)) 131b7e04f8cSWim Van Sebroeck return -EBUSY; 13239309645SAlan Cox 133b7e04f8cSWim Van Sebroeck mixcomwd_ping(); 134b7e04f8cSWim Van Sebroeck 13539309645SAlan Cox if (nowayout) 136b7e04f8cSWim Van Sebroeck /* 137b7e04f8cSWim Van Sebroeck * fops_get() code via open() has already done 138b7e04f8cSWim Van Sebroeck * a try_module_get() so it is safe to do the 139b7e04f8cSWim Van Sebroeck * __module_get(). 140b7e04f8cSWim Van Sebroeck */ 141b7e04f8cSWim Van Sebroeck __module_get(THIS_MODULE); 14239309645SAlan Cox else { 143b7e04f8cSWim Van Sebroeck if (mixcomwd_timer_alive) { 144b7e04f8cSWim Van Sebroeck del_timer(&mixcomwd_timer); 145b7e04f8cSWim Van Sebroeck mixcomwd_timer_alive = 0; 146b7e04f8cSWim Van Sebroeck } 147b7e04f8cSWim Van Sebroeck } 148c5bf68feSKirill Smelkov return stream_open(inode, file); 149b7e04f8cSWim Van Sebroeck } 150b7e04f8cSWim Van Sebroeck 151b7e04f8cSWim Van Sebroeck static int mixcomwd_release(struct inode *inode, struct file *file) 152b7e04f8cSWim Van Sebroeck { 153b7e04f8cSWim Van Sebroeck if (expect_close == 42) { 154b7e04f8cSWim Van Sebroeck if (mixcomwd_timer_alive) { 15527c766aaSJoe Perches pr_err("release called while internal timer alive\n"); 156b7e04f8cSWim Van Sebroeck return -EBUSY; 157b7e04f8cSWim Van Sebroeck } 158b7e04f8cSWim Van Sebroeck mixcomwd_timer_alive = 1; 159b7e04f8cSWim Van Sebroeck mod_timer(&mixcomwd_timer, jiffies + 5 * HZ); 16039309645SAlan Cox } else 16127c766aaSJoe Perches pr_crit("WDT device closed unexpectedly. WDT will not stop!\n"); 162b7e04f8cSWim Van Sebroeck 163b7e04f8cSWim Van Sebroeck clear_bit(0, &mixcomwd_opened); 164b7e04f8cSWim Van Sebroeck expect_close = 0; 165b7e04f8cSWim Van Sebroeck return 0; 166b7e04f8cSWim Van Sebroeck } 167b7e04f8cSWim Van Sebroeck 168b7e04f8cSWim Van Sebroeck 16939309645SAlan Cox static ssize_t mixcomwd_write(struct file *file, const char __user *data, 17039309645SAlan Cox size_t len, loff_t *ppos) 171b7e04f8cSWim Van Sebroeck { 17239309645SAlan Cox if (len) { 173b7e04f8cSWim Van Sebroeck if (!nowayout) { 174b7e04f8cSWim Van Sebroeck size_t i; 175b7e04f8cSWim Van Sebroeck 176b7e04f8cSWim Van Sebroeck /* In case it was set long ago */ 177b7e04f8cSWim Van Sebroeck expect_close = 0; 178b7e04f8cSWim Van Sebroeck 179b7e04f8cSWim Van Sebroeck for (i = 0; i != len; i++) { 180b7e04f8cSWim Van Sebroeck char c; 181b7e04f8cSWim Van Sebroeck if (get_user(c, data + i)) 182b7e04f8cSWim Van Sebroeck return -EFAULT; 183b7e04f8cSWim Van Sebroeck if (c == 'V') 184b7e04f8cSWim Van Sebroeck expect_close = 42; 185b7e04f8cSWim Van Sebroeck } 186b7e04f8cSWim Van Sebroeck } 187b7e04f8cSWim Van Sebroeck mixcomwd_ping(); 188b7e04f8cSWim Van Sebroeck } 189b7e04f8cSWim Van Sebroeck return len; 190b7e04f8cSWim Van Sebroeck } 191b7e04f8cSWim Van Sebroeck 19239309645SAlan Cox static long mixcomwd_ioctl(struct file *file, 193b7e04f8cSWim Van Sebroeck unsigned int cmd, unsigned long arg) 194b7e04f8cSWim Van Sebroeck { 195b7e04f8cSWim Van Sebroeck void __user *argp = (void __user *)arg; 196b7e04f8cSWim Van Sebroeck int __user *p = argp; 197b7e04f8cSWim Van Sebroeck int status; 19842747d71SWim Van Sebroeck static const struct watchdog_info ident = { 199b7e04f8cSWim Van Sebroeck .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, 200b7e04f8cSWim Van Sebroeck .firmware_version = 1, 201b7e04f8cSWim Van Sebroeck .identity = "MixCOM watchdog", 202b7e04f8cSWim Van Sebroeck }; 203b7e04f8cSWim Van Sebroeck 20439309645SAlan Cox switch (cmd) { 2050c06090cSWim Van Sebroeck case WDIOC_GETSUPPORT: 2060c06090cSWim Van Sebroeck if (copy_to_user(argp, &ident, sizeof(ident))) 2070c06090cSWim Van Sebroeck return -EFAULT; 2080c06090cSWim Van Sebroeck break; 209b7e04f8cSWim Van Sebroeck case WDIOC_GETSTATUS: 210b7e04f8cSWim Van Sebroeck status = mixcomwd_opened; 21139309645SAlan Cox if (!nowayout) 212b7e04f8cSWim Van Sebroeck status |= mixcomwd_timer_alive; 21339309645SAlan Cox return put_user(status, p); 214b7e04f8cSWim Van Sebroeck case WDIOC_GETBOOTSTATUS: 21539309645SAlan Cox return put_user(0, p); 216b7e04f8cSWim Van Sebroeck case WDIOC_KEEPALIVE: 217b7e04f8cSWim Van Sebroeck mixcomwd_ping(); 218b7e04f8cSWim Van Sebroeck break; 219b7e04f8cSWim Van Sebroeck default: 220b7e04f8cSWim Van Sebroeck return -ENOTTY; 221b7e04f8cSWim Van Sebroeck } 222b7e04f8cSWim Van Sebroeck return 0; 223b7e04f8cSWim Van Sebroeck } 224b7e04f8cSWim Van Sebroeck 225b7e04f8cSWim Van Sebroeck static const struct file_operations mixcomwd_fops = { 226b7e04f8cSWim Van Sebroeck .owner = THIS_MODULE, 227b7e04f8cSWim Van Sebroeck .llseek = no_llseek, 228b7e04f8cSWim Van Sebroeck .write = mixcomwd_write, 22939309645SAlan Cox .unlocked_ioctl = mixcomwd_ioctl, 230b7e04f8cSWim Van Sebroeck .open = mixcomwd_open, 231b7e04f8cSWim Van Sebroeck .release = mixcomwd_release, 232b7e04f8cSWim Van Sebroeck }; 233b7e04f8cSWim Van Sebroeck 234b7e04f8cSWim Van Sebroeck static struct miscdevice mixcomwd_miscdev = { 235b7e04f8cSWim Van Sebroeck .minor = WATCHDOG_MINOR, 236b7e04f8cSWim Van Sebroeck .name = "watchdog", 237b7e04f8cSWim Van Sebroeck .fops = &mixcomwd_fops, 238b7e04f8cSWim Van Sebroeck }; 239b7e04f8cSWim Van Sebroeck 240b7e04f8cSWim Van Sebroeck static int __init checkcard(int port, int card_id) 241b7e04f8cSWim Van Sebroeck { 242b7e04f8cSWim Van Sebroeck int id; 243b7e04f8cSWim Van Sebroeck 24439309645SAlan Cox if (!request_region(port, 1, "MixCOM watchdog")) 245b7e04f8cSWim Van Sebroeck return 0; 246b7e04f8cSWim Van Sebroeck 247b7e04f8cSWim Van Sebroeck id = inb_p(port); 248b7e04f8cSWim Van Sebroeck if (card_id == MIXCOM_ID) 249b7e04f8cSWim Van Sebroeck id &= 0x3f; 250b7e04f8cSWim Van Sebroeck 251b7e04f8cSWim Van Sebroeck if (id != card_id) { 252b7e04f8cSWim Van Sebroeck release_region(port, 1); 253b7e04f8cSWim Van Sebroeck return 0; 254b7e04f8cSWim Van Sebroeck } 255b7e04f8cSWim Van Sebroeck return 1; 256b7e04f8cSWim Van Sebroeck } 257b7e04f8cSWim Van Sebroeck 258b7e04f8cSWim Van Sebroeck static int __init mixcomwd_init(void) 259b7e04f8cSWim Van Sebroeck { 26039309645SAlan Cox int i, ret, found = 0; 261b7e04f8cSWim Van Sebroeck 262b7e04f8cSWim Van Sebroeck for (i = 0; !found && mixcomwd_io_info[i].ioport != 0; i++) { 263b7e04f8cSWim Van Sebroeck if (checkcard(mixcomwd_io_info[i].ioport, 264b7e04f8cSWim Van Sebroeck mixcomwd_io_info[i].id)) { 265b7e04f8cSWim Van Sebroeck found = 1; 266b7e04f8cSWim Van Sebroeck watchdog_port = mixcomwd_io_info[i].ioport; 267b7e04f8cSWim Van Sebroeck } 268b7e04f8cSWim Van Sebroeck } 269b7e04f8cSWim Van Sebroeck 270b7e04f8cSWim Van Sebroeck if (!found) { 27127c766aaSJoe Perches pr_err("No card detected, or port not available\n"); 272b7e04f8cSWim Van Sebroeck return -ENODEV; 273b7e04f8cSWim Van Sebroeck } 274b7e04f8cSWim Van Sebroeck 275b7e04f8cSWim Van Sebroeck ret = misc_register(&mixcomwd_miscdev); 27639309645SAlan Cox if (ret) { 27727c766aaSJoe Perches pr_err("cannot register miscdev on minor=%d (err=%d)\n", 278b7e04f8cSWim Van Sebroeck WATCHDOG_MINOR, ret); 279b7e04f8cSWim Van Sebroeck goto error_misc_register_watchdog; 280b7e04f8cSWim Van Sebroeck } 281b7e04f8cSWim Van Sebroeck 28227c766aaSJoe Perches pr_info("MixCOM watchdog driver v%s, watchdog port at 0x%3x\n", 283b7e04f8cSWim Van Sebroeck VERSION, watchdog_port); 284b7e04f8cSWim Van Sebroeck 285b7e04f8cSWim Van Sebroeck return 0; 286b7e04f8cSWim Van Sebroeck 287b7e04f8cSWim Van Sebroeck error_misc_register_watchdog: 288b7e04f8cSWim Van Sebroeck release_region(watchdog_port, 1); 289b7e04f8cSWim Van Sebroeck watchdog_port = 0x0000; 290b7e04f8cSWim Van Sebroeck return ret; 291b7e04f8cSWim Van Sebroeck } 292b7e04f8cSWim Van Sebroeck 293b7e04f8cSWim Van Sebroeck static void __exit mixcomwd_exit(void) 294b7e04f8cSWim Van Sebroeck { 295b7e04f8cSWim Van Sebroeck if (!nowayout) { 296b7e04f8cSWim Van Sebroeck if (mixcomwd_timer_alive) { 29727c766aaSJoe Perches pr_warn("I quit now, hardware will probably reboot!\n"); 298b7e04f8cSWim Van Sebroeck del_timer_sync(&mixcomwd_timer); 299b7e04f8cSWim Van Sebroeck mixcomwd_timer_alive = 0; 300b7e04f8cSWim Van Sebroeck } 301b7e04f8cSWim Van Sebroeck } 302b7e04f8cSWim Van Sebroeck misc_deregister(&mixcomwd_miscdev); 303b7e04f8cSWim Van Sebroeck release_region(watchdog_port, 1); 304b7e04f8cSWim Van Sebroeck } 305b7e04f8cSWim Van Sebroeck 306b7e04f8cSWim Van Sebroeck module_init(mixcomwd_init); 307b7e04f8cSWim Van Sebroeck module_exit(mixcomwd_exit); 308b7e04f8cSWim Van Sebroeck 309b7e04f8cSWim Van Sebroeck MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>"); 310b7e04f8cSWim Van Sebroeck MODULE_DESCRIPTION("MixCom Watchdog driver"); 311b7e04f8cSWim Van Sebroeck MODULE_VERSION(VERSION); 312b7e04f8cSWim Van Sebroeck MODULE_LICENSE("GPL"); 313