add optional driver for the hw watchdog on gateworks avila boards (requires soldering to work properly)

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@15300 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 229 insertions, 0 deletions

diff --git a/package/avila-wdt/src/avila-wdt.c b/package/avila-wdt/src/avila-wdt.c
new file mode 100644
index 0000000000..6b3b42b092
--- /dev/null
+++ b/package/avila-wdt/src/avila-wdt.c
@@ -0,0 +1,229 @@
+/*
+ * 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);
+