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path: root/drivers/char/watchdog/mixcomwd.c
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Diffstat (limited to 'drivers/char/watchdog/mixcomwd.c')
-rw-r--r--drivers/char/watchdog/mixcomwd.c306
1 files changed, 306 insertions, 0 deletions
diff --git a/drivers/char/watchdog/mixcomwd.c b/drivers/char/watchdog/mixcomwd.c
new file mode 100644
index 000000000000..3143e4a07535
--- /dev/null
+++ b/drivers/char/watchdog/mixcomwd.c
@@ -0,0 +1,306 @@
+/*
+ * MixCom Watchdog: A Simple Hardware Watchdog Device
+ * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis
+ *
+ * Author: Gergely Madarasz <gorgo@itc.hu>
+ *
+ * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu>
+ *
+ * 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.
+ *
+ * Version 0.1 (99/04/15):
+ * - first version
+ *
+ * Version 0.2 (99/06/16):
+ * - added kernel timer watchdog ping after close
+ * since the hardware does not support watchdog shutdown
+ *
+ * Version 0.3 (99/06/21):
+ * - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls
+ *
+ * Version 0.3.1 (99/06/22):
+ * - allow module removal while internal timer is active,
+ * print warning about probable reset
+ *
+ * Version 0.4 (99/11/15):
+ * - support for one more type board
+ *
+ * Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com>
+ * - added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
+ *
+ */
+
+#define VERSION "0.5"
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/ioport.h>
+#include <linux/watchdog.h>
+#include <linux/fs.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+static int mixcomwd_ioports[] = { 0x180, 0x280, 0x380, 0x000 };
+
+#define MIXCOM_WATCHDOG_OFFSET 0xc10
+#define MIXCOM_ID 0x11
+#define FLASHCOM_WATCHDOG_OFFSET 0x4
+#define FLASHCOM_ID 0x18
+
+static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */
+
+static int watchdog_port;
+static int mixcomwd_timer_alive;
+static struct timer_list mixcomwd_timer = TIMER_INITIALIZER(NULL, 0, 0);
+static char expect_close;
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int nowayout = 1;
+#else
+static int nowayout = 0;
+#endif
+
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
+
+static void mixcomwd_ping(void)
+{
+ outb_p(55,watchdog_port);
+ return;
+}
+
+static void mixcomwd_timerfun(unsigned long d)
+{
+ mixcomwd_ping();
+
+ mod_timer(&mixcomwd_timer,jiffies+ 5*HZ);
+}
+
+/*
+ * Allow only one person to hold it open
+ */
+
+static int mixcomwd_open(struct inode *inode, struct file *file)
+{
+ if(test_and_set_bit(0,&mixcomwd_opened)) {
+ return -EBUSY;
+ }
+ mixcomwd_ping();
+
+ if (nowayout) {
+ /*
+ * fops_get() code via open() has already done
+ * a try_module_get() so it is safe to do the
+ * __module_get().
+ */
+ __module_get(THIS_MODULE);
+ } else {
+ if(mixcomwd_timer_alive) {
+ del_timer(&mixcomwd_timer);
+ mixcomwd_timer_alive=0;
+ }
+ }
+ return nonseekable_open(inode, file);
+}
+
+static int mixcomwd_release(struct inode *inode, struct file *file)
+{
+ if (expect_close == 42) {
+ if(mixcomwd_timer_alive) {
+ printk(KERN_ERR "mixcomwd: release called while internal timer alive");
+ return -EBUSY;
+ }
+ init_timer(&mixcomwd_timer);
+ mixcomwd_timer.expires=jiffies + 5 * HZ;
+ mixcomwd_timer.function=mixcomwd_timerfun;
+ mixcomwd_timer.data=0;
+ mixcomwd_timer_alive=1;
+ add_timer(&mixcomwd_timer);
+ } else {
+ printk(KERN_CRIT "mixcomwd: WDT device closed unexpectedly. WDT will not stop!\n");
+ }
+
+ clear_bit(0,&mixcomwd_opened);
+ expect_close=0;
+ return 0;
+}
+
+
+static ssize_t mixcomwd_write(struct file *file, const char __user *data, size_t len, loff_t *ppos)
+{
+ if(len)
+ {
+ if (!nowayout) {
+ size_t i;
+
+ /* In case it was set long ago */
+ expect_close = 0;
+
+ for (i = 0; i != len; i++) {
+ char c;
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ expect_close = 42;
+ }
+ }
+ mixcomwd_ping();
+ }
+ return len;
+}
+
+static int mixcomwd_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ int __user *p = argp;
+ int status;
+ static struct watchdog_info ident = {
+ .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .firmware_version = 1,
+ .identity = "MixCOM watchdog",
+ };
+
+ switch(cmd)
+ {
+ case WDIOC_GETSTATUS:
+ status=mixcomwd_opened;
+ if (!nowayout) {
+ status|=mixcomwd_timer_alive;
+ }
+ if (copy_to_user(p, &status, sizeof(int))) {
+ return -EFAULT;
+ }
+ break;
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user(argp, &ident, sizeof(ident))) {
+ return -EFAULT;
+ }
+ break;
+ case WDIOC_KEEPALIVE:
+ mixcomwd_ping();
+ break;
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static struct file_operations mixcomwd_fops=
+{
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = mixcomwd_write,
+ .ioctl = mixcomwd_ioctl,
+ .open = mixcomwd_open,
+ .release = mixcomwd_release,
+};
+
+static struct miscdevice mixcomwd_miscdev=
+{
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &mixcomwd_fops,
+};
+
+static int __init mixcomwd_checkcard(int port)
+{
+ int id;
+
+ port += MIXCOM_WATCHDOG_OFFSET;
+ if (!request_region(port, 1, "MixCOM watchdog")) {
+ return 0;
+ }
+
+ id=inb_p(port) & 0x3f;
+ if(id!=MIXCOM_ID) {
+ release_region(port, 1);
+ return 0;
+ }
+ return port;
+}
+
+static int __init flashcom_checkcard(int port)
+{
+ int id;
+
+ port += FLASHCOM_WATCHDOG_OFFSET;
+ if (!request_region(port, 1, "MixCOM watchdog")) {
+ return 0;
+ }
+
+ id=inb_p(port);
+ if(id!=FLASHCOM_ID) {
+ release_region(port, 1);
+ return 0;
+ }
+ return port;
+ }
+
+static int __init mixcomwd_init(void)
+{
+ int i;
+ int ret;
+ int found=0;
+
+ for (i = 0; !found && mixcomwd_ioports[i] != 0; i++) {
+ watchdog_port = mixcomwd_checkcard(mixcomwd_ioports[i]);
+ if (watchdog_port) {
+ found = 1;
+ }
+ }
+
+ /* The FlashCOM card can be set up at 0x300 -> 0x378, in 0x8 jumps */
+ for (i = 0x300; !found && i < 0x380; i+=0x8) {
+ watchdog_port = flashcom_checkcard(i);
+ if (watchdog_port) {
+ found = 1;
+ }
+ }
+
+ if (!found) {
+ printk("mixcomwd: No card detected, or port not available.\n");
+ return -ENODEV;
+ }
+
+ ret = misc_register(&mixcomwd_miscdev);
+ if (ret)
+ {
+ release_region(watchdog_port, 1);
+ return ret;
+ }
+
+ printk(KERN_INFO "MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",VERSION,watchdog_port);
+
+ return 0;
+}
+
+static void __exit mixcomwd_exit(void)
+{
+ if (!nowayout) {
+ if(mixcomwd_timer_alive) {
+ printk(KERN_WARNING "mixcomwd: I quit now, hardware will"
+ " probably reboot!\n");
+ del_timer(&mixcomwd_timer);
+ mixcomwd_timer_alive=0;
+ }
+ }
+ release_region(watchdog_port,1);
+ misc_deregister(&mixcomwd_miscdev);
+}
+
+module_init(mixcomwd_init);
+module_exit(mixcomwd_exit);
+
+MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>");
+MODULE_DESCRIPTION("MixCom Watchdog driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);