--- /dev/null
+/*
+ * avila-wdt.c
+ * Copyright (C) 2009 Felix Fietkau <nbd@openwrt.org>
+ *
+ * based on:
+ * drivers/char/watchdog/ixp4xx_wdt.c
+ *
+ * Watchdog driver for Intel IXP4xx network processors
+ *
+ * Author: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * Copyright 2004 (c) MontaVista, Software, Inc.
+ * Based on sa1100 driver, Copyright (C) 2000 Oleg Drokin <green@crimea.edu>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/uaccess.h>
+#include <mach/hardware.h>
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+static int heartbeat = 20; /* (secs) Default is 20 seconds */
+static unsigned long wdt_status;
+static atomic_t wdt_counter;
+struct timer_list wdt_timer;
+
+#define WDT_IN_USE 0
+#define WDT_OK_TO_CLOSE 1
+#define WDT_RUNNING 2
+
+static void wdt_refresh(unsigned long data)
+{
+ if (test_bit(WDT_RUNNING, &wdt_status)) {
+ if (atomic_dec_and_test(&wdt_counter)) {
+ printk(KERN_WARNING "Avila watchdog expired, expect a reboot soon!\n");
+ clear_bit(WDT_RUNNING, &wdt_status);
+ return;
+ }
+ }
+
+ /* strobe to the watchdog */
+ gpio_line_set(14, IXP4XX_GPIO_HIGH);
+ gpio_line_set(14, IXP4XX_GPIO_LOW);
+
+ mod_timer(&wdt_timer, jiffies + msecs_to_jiffies(500));
+}
+
+static void wdt_enable(void)
+{
+ atomic_set(&wdt_counter, heartbeat * 2);
+
+ /* Disable clock generator output on GPIO 14/15 */
+ *IXP4XX_GPIO_GPCLKR &= ~(1 << 8);
+
+ /* activate GPIO 14 out */
+ gpio_line_config(14, IXP4XX_GPIO_OUT);
+ gpio_line_set(14, IXP4XX_GPIO_LOW);
+
+ if (!test_bit(WDT_RUNNING, &wdt_status))
+ wdt_refresh(0);
+ set_bit(WDT_RUNNING, &wdt_status);
+}
+
+static void wdt_disable(void)
+{
+ /* NB: we can't turn off the watchdog anymore, so we
+ * have to keep running the strobe timer without decrementing
+ * the counter */
+ clear_bit(WDT_RUNNING, &wdt_status);
+}
+
+static int avila_wdt_open(struct inode *inode, struct file *file)
+{
+ if (test_and_set_bit(WDT_IN_USE, &wdt_status))
+ return -EBUSY;
+
+ clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+ wdt_enable();
+ return nonseekable_open(inode, file);
+}
+
+static ssize_t
+avila_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
+{
+ if (len) {
+ if (!nowayout) {
+ size_t i;
+
+ clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+
+ for (i = 0; i != len; i++) {
+ char c;
+
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ set_bit(WDT_OK_TO_CLOSE, &wdt_status);
+ }
+ }
+ wdt_enable();
+ }
+ return len;
+}
+
+static struct watchdog_info ident = {
+ .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE |
+ WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = "Avila Watchdog",
+};
+
+
+static long avila_wdt_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret = -ENOTTY;
+ int time;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ ret = copy_to_user((struct watchdog_info *)arg, &ident,
+ sizeof(ident)) ? -EFAULT : 0;
+ break;
+
+ case WDIOC_GETSTATUS:
+ ret = put_user(0, (int *)arg);
+ break;
+
+ case WDIOC_KEEPALIVE:
+ wdt_enable();
+ ret = 0;
+ break;
+
+ case WDIOC_SETTIMEOUT:
+ ret = get_user(time, (int *)arg);
+ if (ret)
+ break;
+
+ if (time <= 0 || time > 60) {
+ ret = -EINVAL;
+ break;
+ }
+
+ heartbeat = time;
+ wdt_enable();
+ /* Fall through */
+
+ case WDIOC_GETTIMEOUT:
+ ret = put_user(heartbeat, (int *)arg);
+ break;
+ }
+ return ret;
+}
+
+static int avila_wdt_release(struct inode *inode, struct file *file)
+{
+ if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
+ wdt_disable();
+ else
+ printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - "
+ "timer will not stop\n");
+ clear_bit(WDT_IN_USE, &wdt_status);
+ clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+
+ return 0;
+}
+
+
+static const struct file_operations avila_wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = avila_wdt_write,
+ .unlocked_ioctl = avila_wdt_ioctl,
+ .open = avila_wdt_open,
+ .release = avila_wdt_release,
+};
+
+static struct miscdevice avila_wdt_miscdev = {
+ .minor = WATCHDOG_MINOR + 1,
+ .name = "avila_watchdog",
+ .fops = &avila_wdt_fops,
+};
+
+static int __init avila_wdt_init(void)
+{
+ int ret;
+
+ init_timer(&wdt_timer);
+ wdt_timer.expires = 0;
+ wdt_timer.data = 0;
+ wdt_timer.function = wdt_refresh;
+ ret = misc_register(&avila_wdt_miscdev);
+ if (ret == 0)
+ printk(KERN_INFO "Avila Watchdog Timer: heartbeat %d sec\n",
+ heartbeat);
+ return ret;
+}
+
+static void __exit avila_wdt_exit(void)
+{
+ misc_deregister(&avila_wdt_miscdev);
+}
+
+
+module_init(avila_wdt_init);
+module_exit(avila_wdt_exit);
+
+MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
+MODULE_DESCRIPTION("Gateworks Avila Hardware Watchdog");
+
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds (default 20s)");
+
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
+
projects / openwrt.git / commitdiff