| /* |
| * Eurotech CPU-1220/1410 on board WDT driver |
| * |
| * (c) Copyright 2001 Ascensit <support@ascensit.com> |
| * (c) Copyright 2001 Rodolfo Giometti <giometti@ascensit.com> |
| * (c) Copyright 2002 Rob Radez <rob@osinvestor.com> |
| * |
| * Based on wdt.c. |
| * Original copyright messages: |
| * |
| * (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved. |
| * http://www.redhat.com |
| * |
| * 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. |
| * |
| * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide |
| * warranty for any of this software. This material is provided |
| * "AS-IS" and at no charge. |
| * |
| * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>* |
| */ |
| |
| /* Changelog: |
| * |
| * 2002/04/25 - Rob Radez |
| * clean up #includes |
| * clean up locking |
| * make __setup param unique |
| * proper options in watchdog_info |
| * add WDIOC_GETSTATUS and WDIOC_SETOPTIONS ioctls |
| * add expect_close support |
| * |
| * 2001 - Rodolfo Giometti |
| * Initial release |
| * |
| * 2002.05.30 - Joel Becker <joel.becker@oracle.com> |
| * Added Matt Domsch's nowayout module option. |
| */ |
| |
| #include <linux/interrupt.h> |
| #include <linux/module.h> |
| #include <linux/moduleparam.h> |
| #include <linux/types.h> |
| #include <linux/miscdevice.h> |
| #include <linux/watchdog.h> |
| #include <linux/fs.h> |
| #include <linux/ioport.h> |
| #include <linux/notifier.h> |
| #include <linux/reboot.h> |
| #include <linux/init.h> |
| |
| #include <asm/io.h> |
| #include <asm/uaccess.h> |
| #include <asm/system.h> |
| |
| static unsigned long eurwdt_is_open; |
| static int eurwdt_timeout; |
| static char eur_expect_close; |
| |
| /* |
| * You must set these - there is no sane way to probe for this board. |
| * You can use eurwdt=x,y to set these now. |
| */ |
| |
| static int io = 0x3f0; |
| static int irq = 10; |
| static char *ev = "int"; |
| |
| #define WDT_TIMEOUT 60 /* 1 minute */ |
| |
| static int nowayout = WATCHDOG_NOWAYOUT; |
| module_param(nowayout, int, 0); |
| MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); |
| |
| /* |
| * Some symbolic names |
| */ |
| |
| #define WDT_CTRL_REG 0x30 |
| #define WDT_OUTPIN_CFG 0xe2 |
| #define WDT_EVENT_INT 0x00 |
| #define WDT_EVENT_REBOOT 0x08 |
| #define WDT_UNIT_SEL 0xf1 |
| #define WDT_UNIT_SECS 0x80 |
| #define WDT_TIMEOUT_VAL 0xf2 |
| #define WDT_TIMER_CFG 0xf3 |
| |
| |
| module_param(io, int, 0); |
| MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)"); |
| module_param(irq, int, 0); |
| MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)"); |
| module_param(ev, charp, 0); |
| MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')"); |
| |
| |
| /* |
| * Programming support |
| */ |
| |
| static inline void eurwdt_write_reg(u8 index, u8 data) |
| { |
| outb(index, io); |
| outb(data, io+1); |
| } |
| |
| static inline void eurwdt_lock_chip(void) |
| { |
| outb(0xaa, io); |
| } |
| |
| static inline void eurwdt_unlock_chip(void) |
| { |
| outb(0x55, io); |
| eurwdt_write_reg(0x07, 0x08); /* set the logical device */ |
| } |
| |
| static inline void eurwdt_set_timeout(int timeout) |
| { |
| eurwdt_write_reg(WDT_TIMEOUT_VAL, (u8) timeout); |
| } |
| |
| static inline void eurwdt_disable_timer(void) |
| { |
| eurwdt_set_timeout(0); |
| } |
| |
| static void eurwdt_activate_timer(void) |
| { |
| eurwdt_disable_timer(); |
| eurwdt_write_reg(WDT_CTRL_REG, 0x01); /* activate the WDT */ |
| eurwdt_write_reg(WDT_OUTPIN_CFG, !strcmp("int", ev) ? WDT_EVENT_INT : WDT_EVENT_REBOOT); |
| |
| /* Setting interrupt line */ |
| if (irq == 2 || irq > 15 || irq < 0) { |
| printk(KERN_ERR ": invalid irq number\n"); |
| irq = 0; /* if invalid we disable interrupt */ |
| } |
| if (irq == 0) |
| printk(KERN_INFO ": interrupt disabled\n"); |
| |
| eurwdt_write_reg(WDT_TIMER_CFG, irq<<4); |
| |
| eurwdt_write_reg(WDT_UNIT_SEL, WDT_UNIT_SECS); /* we use seconds */ |
| eurwdt_set_timeout(0); /* the default timeout */ |
| } |
| |
| |
| /* |
| * Kernel methods. |
| */ |
| |
| static irqreturn_t eurwdt_interrupt(int irq, void *dev_id, struct pt_regs *regs) |
| { |
| printk(KERN_CRIT "timeout WDT timeout\n"); |
| |
| #ifdef ONLY_TESTING |
| printk(KERN_CRIT "Would Reboot.\n"); |
| #else |
| printk(KERN_CRIT "Initiating system reboot.\n"); |
| emergency_restart(); |
| #endif |
| return IRQ_HANDLED; |
| } |
| |
| |
| /** |
| * eurwdt_ping: |
| * |
| * Reload counter one with the watchdog timeout. |
| */ |
| |
| static void eurwdt_ping(void) |
| { |
| /* Write the watchdog default value */ |
| eurwdt_set_timeout(eurwdt_timeout); |
| } |
| |
| /** |
| * eurwdt_write: |
| * @file: file handle to the watchdog |
| * @buf: buffer to write (unused as data does not matter here |
| * @count: count of bytes |
| * @ppos: pointer to the position to write. No seeks allowed |
| * |
| * A write to a watchdog device is defined as a keepalive signal. Any |
| * write of data will do, as we we don't define content meaning. |
| */ |
| |
| static ssize_t eurwdt_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| if (count) { |
| if (!nowayout) { |
| size_t i; |
| |
| eur_expect_close = 0; |
| |
| for (i = 0; i != count; i++) { |
| char c; |
| if(get_user(c, buf+i)) |
| return -EFAULT; |
| if (c == 'V') |
| eur_expect_close = 42; |
| } |
| } |
| eurwdt_ping(); /* the default timeout */ |
| } |
| |
| return count; |
| } |
| |
| /** |
| * eurwdt_ioctl: |
| * @inode: inode of the device |
| * @file: file handle to the device |
| * @cmd: watchdog command |
| * @arg: argument pointer |
| * |
| * The watchdog API defines a common set of functions for all watchdogs |
| * according to their available features. |
| */ |
| |
| static int eurwdt_ioctl(struct inode *inode, struct file *file, |
| unsigned int cmd, unsigned long arg) |
| { |
| void __user *argp = (void __user *)arg; |
| int __user *p = argp; |
| static struct watchdog_info ident = { |
| .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, |
| .firmware_version = 1, |
| .identity = "WDT Eurotech CPU-1220/1410", |
| }; |
| |
| int time; |
| int options, retval = -EINVAL; |
| |
| switch(cmd) { |
| default: |
| return -ENOIOCTLCMD; |
| |
| case WDIOC_GETSUPPORT: |
| return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; |
| |
| case WDIOC_GETSTATUS: |
| case WDIOC_GETBOOTSTATUS: |
| return put_user(0, p); |
| |
| case WDIOC_KEEPALIVE: |
| eurwdt_ping(); |
| return 0; |
| |
| case WDIOC_SETTIMEOUT: |
| if (copy_from_user(&time, p, sizeof(int))) |
| return -EFAULT; |
| |
| /* Sanity check */ |
| if (time < 0 || time > 255) |
| return -EINVAL; |
| |
| eurwdt_timeout = time; |
| eurwdt_set_timeout(time); |
| /* Fall */ |
| |
| case WDIOC_GETTIMEOUT: |
| return put_user(eurwdt_timeout, p); |
| |
| case WDIOC_SETOPTIONS: |
| if (get_user(options, p)) |
| return -EFAULT; |
| if (options & WDIOS_DISABLECARD) { |
| eurwdt_disable_timer(); |
| retval = 0; |
| } |
| if (options & WDIOS_ENABLECARD) { |
| eurwdt_activate_timer(); |
| eurwdt_ping(); |
| retval = 0; |
| } |
| return retval; |
| } |
| } |
| |
| /** |
| * eurwdt_open: |
| * @inode: inode of device |
| * @file: file handle to device |
| * |
| * The misc device has been opened. The watchdog device is single |
| * open and on opening we load the counter. |
| */ |
| |
| static int eurwdt_open(struct inode *inode, struct file *file) |
| { |
| if (test_and_set_bit(0, &eurwdt_is_open)) |
| return -EBUSY; |
| eurwdt_timeout = WDT_TIMEOUT; /* initial timeout */ |
| /* Activate the WDT */ |
| eurwdt_activate_timer(); |
| return nonseekable_open(inode, file); |
| } |
| |
| /** |
| * eurwdt_release: |
| * @inode: inode to board |
| * @file: file handle to board |
| * |
| * The watchdog has a configurable API. There is a religious dispute |
| * between people who want their watchdog to be able to shut down and |
| * those who want to be sure if the watchdog manager dies the machine |
| * reboots. In the former case we disable the counters, in the latter |
| * case you have to open it again very soon. |
| */ |
| |
| static int eurwdt_release(struct inode *inode, struct file *file) |
| { |
| if (eur_expect_close == 42) { |
| eurwdt_disable_timer(); |
| } else { |
| printk(KERN_CRIT "eurwdt: Unexpected close, not stopping watchdog!\n"); |
| eurwdt_ping(); |
| } |
| clear_bit(0, &eurwdt_is_open); |
| eur_expect_close = 0; |
| return 0; |
| } |
| |
| /** |
| * eurwdt_notify_sys: |
| * @this: our notifier block |
| * @code: the event being reported |
| * @unused: unused |
| * |
| * Our notifier is called on system shutdowns. We want to turn the card |
| * off at reboot otherwise the machine will reboot again during memory |
| * test or worse yet during the following fsck. This would suck, in fact |
| * trust me - if it happens it does suck. |
| */ |
| |
| static int eurwdt_notify_sys(struct notifier_block *this, unsigned long code, |
| void *unused) |
| { |
| if (code == SYS_DOWN || code == SYS_HALT) { |
| /* Turn the card off */ |
| eurwdt_disable_timer(); |
| } |
| |
| return NOTIFY_DONE; |
| } |
| |
| /* |
| * Kernel Interfaces |
| */ |
| |
| |
| static struct file_operations eurwdt_fops = { |
| .owner = THIS_MODULE, |
| .llseek = no_llseek, |
| .write = eurwdt_write, |
| .ioctl = eurwdt_ioctl, |
| .open = eurwdt_open, |
| .release = eurwdt_release, |
| }; |
| |
| static struct miscdevice eurwdt_miscdev = { |
| .minor = WATCHDOG_MINOR, |
| .name = "watchdog", |
| .fops = &eurwdt_fops, |
| }; |
| |
| /* |
| * The WDT card needs to learn about soft shutdowns in order to |
| * turn the timebomb registers off. |
| */ |
| |
| static struct notifier_block eurwdt_notifier = { |
| .notifier_call = eurwdt_notify_sys, |
| }; |
| |
| /** |
| * cleanup_module: |
| * |
| * Unload the watchdog. You cannot do this with any file handles open. |
| * If your watchdog is set to continue ticking on close and you unload |
| * it, well it keeps ticking. We won't get the interrupt but the board |
| * will not touch PC memory so all is fine. You just have to load a new |
| * module in 60 seconds or reboot. |
| */ |
| |
| static void __exit eurwdt_exit(void) |
| { |
| eurwdt_lock_chip(); |
| |
| misc_deregister(&eurwdt_miscdev); |
| |
| unregister_reboot_notifier(&eurwdt_notifier); |
| release_region(io, 2); |
| free_irq(irq, NULL); |
| } |
| |
| /** |
| * eurwdt_init: |
| * |
| * Set up the WDT watchdog board. After grabbing the resources |
| * we require we need also to unlock the device. |
| * The open() function will actually kick the board off. |
| */ |
| |
| static int __init eurwdt_init(void) |
| { |
| int ret; |
| |
| ret = misc_register(&eurwdt_miscdev); |
| if (ret) { |
| printk(KERN_ERR "eurwdt: can't misc_register on minor=%d\n", |
| WATCHDOG_MINOR); |
| goto out; |
| } |
| |
| ret = request_irq(irq, eurwdt_interrupt, SA_INTERRUPT, "eurwdt", NULL); |
| if(ret) { |
| printk(KERN_ERR "eurwdt: IRQ %d is not free.\n", irq); |
| goto outmisc; |
| } |
| |
| if (!request_region(io, 2, "eurwdt")) { |
| printk(KERN_ERR "eurwdt: IO %X is not free.\n", io); |
| ret = -EBUSY; |
| goto outirq; |
| } |
| |
| ret = register_reboot_notifier(&eurwdt_notifier); |
| if (ret) { |
| printk(KERN_ERR "eurwdt: can't register reboot notifier (err=%d)\n", ret); |
| goto outreg; |
| } |
| |
| eurwdt_unlock_chip(); |
| |
| ret = 0; |
| printk(KERN_INFO "Eurotech WDT driver 0.01 at %X (Interrupt %d)" |
| " - timeout event: %s\n", |
| io, irq, (!strcmp("int", ev) ? "int" : "reboot")); |
| |
| out: |
| return ret; |
| |
| outreg: |
| release_region(io, 2); |
| |
| outirq: |
| free_irq(irq, NULL); |
| |
| outmisc: |
| misc_deregister(&eurwdt_miscdev); |
| goto out; |
| } |
| |
| module_init(eurwdt_init); |
| module_exit(eurwdt_exit); |
| |
| MODULE_AUTHOR("Rodolfo Giometti"); |
| MODULE_DESCRIPTION("Driver for Eurotech CPU-1220/1410 on board watchdog"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |