--- /dev/null
+/*
+ * RDC321x watchdog driver
+ *
+ * Copyright (C) 2007 Florian Fainelli <florian@openwrt.org>
+ *
+ * This driver is highly inspired from the rdc321x_wdt driver
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/timer.h>
+#include <linux/completion.h>
+#include <linux/jiffies.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+#include <asm/mach-rdc/rdc321x_defs.h>
+
+#define RDC_WDT_MASK 0x80000000 /* Mask */
+#define RDC_WDT_EN 0x00800000 /* Enable bit */
+#define RDC_WDT_WTI 0x00200000 /* Generate a CPU reset/NMI/WDT irq when WDT timeout is reached */
+#define RDC_WDT_RST 0x00100000 /* Reset bit */
+#define RDC_WDT_WIF 0x00040000 /* WDT IRQ Flag */
+#define RDC_WDT_IRT 0x00000100 /* IRQ Routing table */
+#define RDC_WDT_CNT 0x00000001 /* WDT count */
+
+#define RDC_CLS_TMR 0x80003844 /* Clear timer */
+
+#define RDC_WDT_INTERVAL (HZ/10+1)
+
+int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static int ticks = 1000;
+
+/* some device data */
+
+static struct {
+ struct completion stop;
+ volatile int running;
+ struct timer_list timer;
+ volatile int queue;
+ int default_ticks;
+ unsigned long inuse;
+} rdc321x_wdt_device;
+
+/* generic helper functions */
+
+static void rdc321x_wdt_trigger(unsigned long unused)
+{
+ if( rdc321x_wdt_device.running )
+ ticks--;
+
+ /* keep watchdog alive */
+ outl(RDC_WDT_EN|inl(RDC3210_CFGREG_DATA), RDC3210_CFGREG_DATA);
+
+ /* requeue?? */
+ if (rdc321x_wdt_device.queue && ticks)
+ mod_timer(&rdc321x_wdt_device.timer, jiffies + RDC_WDT_INTERVAL);
+ else {
+ /* ticks doesn't matter anyway */
+ complete(&rdc321x_wdt_device.stop);
+ }
+
+}
+
+static void rdc321x_wdt_reset(void)
+{
+ ticks = rdc321x_wdt_device.default_ticks;
+}
+
+static void rdc321x_wdt_start(void)
+{
+ if (!rdc321x_wdt_device.queue) {
+ rdc321x_wdt_device.queue = 1;
+
+ /* Clear the timer */
+ outl(RDC_CLS_TMR, RDC3210_CFGREG_ADDR);
+
+ /* Enable watchdog and set the timeout to 81.92 us */
+ outl(RDC_WDT_EN|RDC_WDT_CNT, RDC3210_CFGREG_DATA);
+
+ mod_timer(&rdc321x_wdt_device.timer, jiffies + RDC_WDT_INTERVAL);
+ }
+
+ /* if process dies, counter is not decremented */
+ rdc321x_wdt_device.running++;
+}
+
+static int rdc321x_wdt_stop(void)
+{
+ if (rdc321x_wdt_device.running)
+ rdc321x_wdt_device.running = 0;
+
+ ticks = rdc321x_wdt_device.default_ticks;
+
+ return -EIO;
+}
+
+/* filesystem operations */
+
+static int rdc321x_wdt_open(struct inode *inode, struct file *file)
+{
+ if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
+ return -EBUSY;
+
+ return nonseekable_open(inode, file);
+}
+
+static int rdc321x_wdt_release(struct inode *inode, struct file *file)
+{
+ clear_bit(0, &rdc321x_wdt_device.inuse);
+ return 0;
+}
+
+static int rdc321x_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ unsigned int value;
+ static struct watchdog_info ident =
+ {
+ .options = WDIOF_CARDRESET,
+ .identity = "RDC321x WDT",
+ };
+
+ switch(cmd) {
+ case WDIOC_KEEPALIVE:
+ rdc321x_wdt_reset();
+ break;
+ case WDIOC_GETSTATUS:
+ /* Read the value from the DATA register */
+ value = inl(RDC3210_CFGREG_DATA);
+ if ( copy_to_user(argp, &value, sizeof(int)) )
+ return -EFAULT;
+ break;
+ case WDIOC_GETSUPPORT:
+ if ( copy_to_user(argp, &ident, sizeof(ident)) )
+ return -EFAULT;
+ break;
+ case WDIOC_SETOPTIONS:
+ if ( copy_from_user(&value, argp, sizeof(int)) )
+ return -EFAULT;
+ switch(value) {
+ case WDIOS_ENABLECARD:
+ rdc321x_wdt_start();
+ break;
+ case WDIOS_DISABLECARD:
+ return rdc321x_wdt_stop();
+ default:
+ return -EINVAL;
+ }
+ break;
+ default:
+ return -ENOTTY;
+ }
+ return 0;
+}
+
+static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
+{
+ if ( !count )
+ return -EIO;
+
+ rdc321x_wdt_reset();
+
+ return count;
+}
+
+static const struct file_operations rdc321x_wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .ioctl = rdc321x_wdt_ioctl,
+ .open = rdc321x_wdt_open,
+ .write = rdc321x_wdt_write,
+ .release = rdc321x_wdt_release,
+};
+
+static struct miscdevice rdc321x_wdt_misc = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &rdc321x_wdt_fops,
+};
+
+static int __devinit rdc321x_wdt_probe(struct platform_device *pdev)
+{
+ int err;
+
+ if ( (err = misc_register(&rdc321x_wdt_misc)) < 0 ) {
+ printk(KERN_ERR PFX "misc_register failed\n");
+ goto no_misc;
+ }
+
+ /* Reset the watchdog */
+ outl(RDC_WDT_RST, RDC3210_CFGREG_DATA);
+
+ init_completion(&rdc321x_wdt_device.stop);
+ rdc321x_wdt_device.queue = 0;
+
+ clear_bit(0, &rdc321x_wdt_device.inuse);
+
+ setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
+
+ rdc321x_wdt_device.default_ticks = ticks;
+
+ printk(KERN_INFO PFX "init success\n");
+
+ return 0;
+
+no_misc:
+ return err;
+}
+
+static int rdc321x_wdt_remove(struct platform_device *pdev)
+{
+ if (rdc321x_wdt_device.queue) {
+ rdc321x_wdt_device.queue = 0;
+ wait_for_completion(&rdc321x_wdt_device.stop);
+ }
+
+ misc_deregister(&rdc321x_wdt_misc);
+
+ return 0;
+}
+
+static struct platform_driver rdc321x_wdt_driver = {
+ .probe = rdc321x_wdt_probe,
+ .remove = rdc321x_wdt_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "rdc321x_wdt",
+ },
+};
+
+static int __init rdc321x_wdt_init(void)
+{
+ return platform_driver_register(&rdc321x_wdt_driver);
+}
+
+static void __exit rdc321x_wdt_exit(void)
+{
+ platform_driver_unregister(&rdc321x_wdt_driver);
+}
+
+module_init(rdc321x_wdt_init);
+module_exit(rdc321x_wdt_exit);
+
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("RDC321x watchdog driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
projects / openwrt / staging / florian.git / commitdiff