--- /dev/null
+/*
+ * w83697ug/uf WDT driver
+ *
+ * (c) Copyright 2008 Flemming Fransen <ff@nrvissing.net>
+ * reused original code to supoprt w83697ug/uf.
+ *
+ * Based on w83627hf_wdt.c which is based on advantechwdt.c
+ * which is based on wdt.c.
+ * Original copyright messages:
+ *
+ * (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
+ * added support for W83627THF.
+ *
+ * (c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
+ *
+ * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
+ *
+ * (c) Copyright 1996 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@redhat.com>
+ */
+
+#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 <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+
+#include <asm/system.h>
+
+#define WATCHDOG_NAME "w83697ug/uf WDT"
+#define PFX WATCHDOG_NAME ": "
+#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
+
+static unsigned long wdt_is_open;
+static char expect_close;
+static DEFINE_SPINLOCK(io_lock);
+
+static int wdt_io = 0x2e;
+module_param(wdt_io, int, 0);
+MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)");
+
+static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout,
+ "Watchdog timeout in seconds. 1<= timeout <=255 (default="
+ __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout,
+ "Watchdog cannot be stopped once started (default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+/*
+ * Kernel methods.
+ */
+
+#define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */
+#define WDT_EFIR (wdt_io+0) /* Extended Function Index Register
+ (same as EFER) */
+#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
+
+static void w83697ug_select_wd_register(void)
+{
+ unsigned char c;
+ unsigned char version;
+
+ outb_p(0x87, WDT_EFER); /* Enter extended function mode */
+ outb_p(0x87, WDT_EFER); /* Again according to manual */
+
+ outb(0x20, WDT_EFER); /* check chip version */
+ version = inb(WDT_EFDR);
+
+ if (version == 0x68) { /* W83697UG */
+ printk(KERN_INFO PFX "Watchdog chip version 0x%02x = "
+ "W83697UG/UF found at 0x%04x\n", version, wdt_io);
+
+ outb_p(0x2b, WDT_EFER);
+ c = inb_p(WDT_EFDR); /* select WDT0 */
+ c &= ~0x04;
+ outb_p(0x2b, WDT_EFER);
+ outb_p(c, WDT_EFDR); /* set pin118 to WDT0 */
+
+ } else {
+ printk(KERN_ERR PFX "No W83697UG/UF could be found\n");
+ return -EIO;
+ }
+
+ outb_p(0x07, WDT_EFER); /* point to logical device number reg */
+ outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
+ outb_p(0x30, WDT_EFER); /* select CR30 */
+ c = inb_p(WDT_EFDR);
+ outb_p(c || 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */
+}
+
+static void w83697ug_unselect_wd_register(void)
+{
+ outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
+}
+
+static void w83697ug_init(void)
+{
+ unsigned char t;
+
+ w83697ug_select_wd_register();
+
+ outb_p(0xF6, WDT_EFER); /* Select CRF6 */
+ t = inb_p(WDT_EFDR); /* read CRF6 */
+ if (t != 0) {
+ printk(KERN_INFO PFX "Watchdog already running."
+ " Resetting timeout to %d sec\n", timeout);
+ outb_p(timeout, WDT_EFDR); /* Write back to CRF6 */
+ }
+ outb_p(0xF5, WDT_EFER); /* Select CRF5 */
+ t = inb_p(WDT_EFDR); /* read CRF5 */
+ t &= ~0x0C; /* set second mode &
+ disable keyboard turning off watchdog */
+ outb_p(t, WDT_EFDR); /* Write back to CRF5 */
+
+ w83697ug_unselect_wd_register();
+}
+
+static void wdt_ctrl(int timeout)
+{
+ spin_lock(&io_lock);
+
+ w83697ug_select_wd_register();
+
+ outb_p(0xF4, WDT_EFER); /* Select CRF4 */
+ outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */
+
+ w83697ug_unselect_wd_register();
+
+ spin_unlock(&io_lock);
+}
+
+static int wdt_ping(void)
+{
+ wdt_ctrl(timeout);
+ return 0;
+}
+
+static int wdt_disable(void)
+{
+ wdt_ctrl(0);
+ return 0;
+}
+
+static int wdt_set_heartbeat(int t)
+{
+ if (t < 1 || t > 255)
+ return -EINVAL;
+
+ timeout = t;
+ return 0;
+}
+
+static ssize_t wdt_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ if (count) {
+ if (!nowayout) {
+ size_t i;
+
+ expect_close = 0;
+
+ for (i = 0; i != count; i++) {
+ char c;
+ if (get_user(c, buf + i))
+ return -EFAULT;
+ if (c == 'V')
+ expect_close = 42;
+ }
+ }
+ wdt_ping();
+ }
+ return count;
+}
+
+static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ int __user *p = argp;
+ int new_timeout;
+ static const struct watchdog_info ident = {
+ .options = WDIOF_KEEPALIVEPING |
+ WDIOF_SETTIMEOUT |
+ WDIOF_MAGICCLOSE,
+ .firmware_version = 1,
+ .identity = "W83697UG WDT",
+ };
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user(argp, &ident, sizeof(ident)))
+ return -EFAULT;
+ break;
+
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, p);
+
+ case WDIOC_SETOPTIONS:
+ {
+ int options, retval = -EINVAL;
+
+ if (get_user(options, p))
+ return -EFAULT;
+
+ if (options & WDIOS_DISABLECARD) {
+ wdt_disable();
+ retval = 0;
+ }
+
+ if (options & WDIOS_ENABLECARD) {
+ wdt_ping();
+ retval = 0;
+ }
+
+ return retval;
+ }
+
+ case WDIOC_KEEPALIVE:
+ wdt_ping();
+ break;
+
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_timeout, p))
+ return -EFAULT;
+ if (wdt_set_heartbeat(new_timeout))
+ return -EINVAL;
+ wdt_ping();
+ /* Fall */
+
+ case WDIOC_GETTIMEOUT:
+ return put_user(timeout, p);
+
+ default:
+ return -ENOTTY;
+ }
+ return 0;
+}
+
+static int wdt_open(struct inode *inode, struct file *file)
+{
+ if (test_and_set_bit(0, &wdt_is_open))
+ return -EBUSY;
+ /*
+ * Activate
+ */
+
+ wdt_ping();
+ return nonseekable_open(inode, file);
+}
+
+static int wdt_close(struct inode *inode, struct file *file)
+{
+ if (expect_close == 42)
+ wdt_disable();
+ else {
+ printk(KERN_CRIT PFX
+ "Unexpected close, not stopping watchdog!\n");
+ wdt_ping();
+ }
+ expect_close = 0;
+ clear_bit(0, &wdt_is_open);
+ return 0;
+}
+
+/*
+ * Notifier for system down
+ */
+
+static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ if (code == SYS_DOWN || code == SYS_HALT)
+ wdt_disable(); /* Turn the WDT off */
+
+ return NOTIFY_DONE;
+}
+
+/*
+ * Kernel Interfaces
+ */
+
+static const struct file_operations wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = wdt_write,
+ .unlocked_ioctl = wdt_ioctl,
+ .open = wdt_open,
+ .release = wdt_close,
+};
+
+static struct miscdevice wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &wdt_fops,
+};
+
+/*
+ * The WDT needs to learn about soft shutdowns in order to
+ * turn the timebomb registers off.
+ */
+
+static struct notifier_block wdt_notifier = {
+ .notifier_call = wdt_notify_sys,
+};
+
+static int __init wdt_init(void)
+{
+ int ret;
+
+ printk(KERN_INFO "WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising.\n");
+
+ if (wdt_set_heartbeat(timeout)) {
+ wdt_set_heartbeat(WATCHDOG_TIMEOUT);
+ printk(KERN_INFO PFX
+ "timeout value must be 1<=timeout<=255, using %d\n",
+ WATCHDOG_TIMEOUT);
+ }
+
+ if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
+ printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
+ wdt_io);
+ ret = -EIO;
+ goto out;
+ }
+
+ w83697ug_init();
+
+ ret = register_reboot_notifier(&wdt_notifier);
+ if (ret != 0) {
+ printk(KERN_ERR PFX
+ "cannot register reboot notifier (err=%d)\n", ret);
+ goto unreg_regions;
+ }
+
+ ret = misc_register(&wdt_miscdev);
+ if (ret != 0) {
+ printk(KERN_ERR PFX
+ "cannot register miscdev on minor=%d (err=%d)\n",
+ WATCHDOG_MINOR, ret);
+ goto unreg_reboot;
+ }
+
+ printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
+ timeout, nowayout);
+
+out:
+ return ret;
+unreg_reboot:
+ unregister_reboot_notifier(&wdt_notifier);
+unreg_regions:
+ release_region(wdt_io, 1);
+ goto out;
+}
+
+static void __exit wdt_exit(void)
+{
+ misc_deregister(&wdt_miscdev);
+ unregister_reboot_notifier(&wdt_notifier);
+ release_region(wdt_io, 1);
+}
+
+module_init(wdt_init);
+module_exit(wdt_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>");
+MODULE_DESCRIPTION("w83697ug/uf WDT driver");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
projects / linux-2.6-omap-h63xx.git / commitdiff