--- /dev/null
+/*
+ * Broadcom BCM63xx SoC watchdog driver
+ *
+ * Copyright (C) 2007, Miguel Gaio <miguel.gaio@efixo.com>
+ * Copyright (C) 2008, Florian Fainelli <florian@openwrt.org>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/reboot.h>
+#include <linux/smp_lock.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/timer.h>
+
+#include <bcm63xx_cpu.h>
+#include <bcm63xx_io.h>
+#include <bcm63xx_regs.h>
+
+#define PFX KBUILD_MODNAME
+
+#define WDT_HZ 50000000 /* Fclk */
+#define WDT_INTERVAL (40) /* in seconds */
+
+static struct {
+ void __iomem *regs;
+ struct completion stop;
+ int running;
+ struct timer_list timer;
+ int queue;
+ int default_ticks;
+ unsigned long inuse;
+} bcm63xx_wdt_device;
+
+static int ticks = 100 * WDT_HZ;
+
+static int expect_close;
+static int 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) ")");
+
+
+static void bcm63xx_wdt_toggle(void)
+{
+ bcm_writel(WDT_START_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);
+ bcm_writel(WDT_START_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);
+}
+
+static void bcm63xx_wdt_start(void)
+{
+ if (!bcm63xx_wdt_device.inuse) {
+ bcm63xx_wdt_toggle();
+ mod_timer(&bcm63xx_wdt_device.timer, jiffies + WDT_INTERVAL);
+ }
+
+ bcm63xx_wdt_device.running++;
+}
+
+static void bcm63xx_wdt_stop(void)
+{
+ if (bcm63xx_wdt_device.running) {
+ bcm_writel(WDT_STOP_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);
+ bcm_writel(WDT_STOP_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);
+
+ bcm63xx_wdt_device.running = 0;
+ }
+}
+
+static void bcm63xx_wdt_set(int new_timeout)
+{
+ new_timeout *= WDT_HZ;
+ bcm_writel(new_timeout, bcm63xx_wdt_device.regs + WDT_DEFVAL_REG);
+}
+
+static void bcm63xx_wdt_reset(void)
+{
+ ticks = bcm63xx_wdt_device.default_ticks;
+}
+
+static void bcm63xx_wdt_update(unsigned long unused)
+{
+ if (bcm63xx_wdt_device.running)
+ ticks--;
+
+ bcm63xx_wdt_toggle();
+
+ if (bcm63xx_wdt_device.queue && ticks)
+ mod_timer(&bcm63xx_wdt_device.timer,
+ jiffies + WDT_INTERVAL);
+ else
+ complete(&bcm63xx_wdt_device.stop);
+}
+
+static int bcm63xx_wdt_open(struct inode *inode, struct file *file)
+{
+ if (test_and_set_bit(0, &bcm63xx_wdt_device.inuse))
+ return -EBUSY;
+
+ if (nowayout)
+ __module_get(THIS_MODULE);
+
+ return nonseekable_open(inode, file);
+}
+
+static int bcm63xx_wdt_release(struct inode *inode, struct file *file)
+{
+ if (expect_close && nowayout == 0) {
+ bcm63xx_wdt_stop();
+ printk(KERN_INFO PFX ": disabling watchdog timer\n");
+ module_put(THIS_MODULE);
+ } else
+ printk(KERN_CRIT PFX
+ ": device closed unexpectedly. WDT will not stop !\n");
+
+ clear_bit(0, &bcm63xx_wdt_device.inuse);
+ return 0;
+}
+
+static ssize_t bcm63xx_wdt_write(struct file *file, const char *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 = 1;
+ }
+ }
+ bcm63xx_wdt_update(0);
+ return len;
+ }
+ return 0;
+}
+
+static long bcm63xx_wdt_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ int new_timeout;
+ unsigned int value;
+ static struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+ .identity = "BCM63xx Watchdog",
+ };
+ switch (cmd) {
+ case WDIOC_KEEPALIVE:
+ bcm63xx_wdt_reset();
+ break;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ value = bcm_readl(bcm63xx_wdt_device.regs + WDT_DEFVAL_REG);
+ 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:
+ bcm63xx_wdt_start();
+ break;
+ case WDIOS_DISABLECARD:
+ bcm63xx_wdt_stop();
+ default:
+ return -EINVAL;
+ }
+ break;
+ case WDIOC_SETTIMEOUT:
+ if (copy_from_user(&new_timeout, argp, sizeof(int)))
+ return -EFAULT;
+ if (new_timeout < 5)
+ return -EINVAL;
+ if (new_timeout > 40)
+ return -EINVAL;
+ bcm63xx_wdt_set(new_timeout);
+ bcm63xx_wdt_toggle();
+ case WDIOC_GETTIMEOUT:
+ return copy_to_user(argp, &timeout, sizeof(int));
+ default:
+ return -ENOTTY;
+ }
+
+ return 0;
+}
+
+static struct file_operations bcm63xx_wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = bcm63xx_wdt_write,
+ .unlocked_ioctl = bcm63xx_wdt_ioctl,
+ .open = bcm63xx_wdt_open,
+ .release = bcm63xx_wdt_release,
+};
+
+static struct miscdevice bcm63xx_wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &bcm63xx_wdt_fops,
+};
+
+static int bcm63xx_wdt_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct resource *r;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ printk(KERN_ERR PFX
+ "failed to retrieve resources\n");
+ return -ENODEV;
+ }
+
+ bcm63xx_wdt_device.regs = ioremap_nocache(r->start, r->end - r->start);
+ if (!bcm63xx_wdt_device.regs) {
+ printk(KERN_ERR PFX
+ "failed to remap I/O resources\n");
+ return -ENXIO;
+ }
+
+ ret = misc_register(&bcm63xx_wdt_miscdev);
+ if (ret < 0) {
+ printk(KERN_ERR PFX
+ "failed to register watchdog device\n");
+ goto unmap;
+ }
+
+ init_completion(&bcm63xx_wdt_device.stop);
+ bcm63xx_wdt_device.queue = 0;
+
+ clear_bit(0, &bcm63xx_wdt_device.inuse);
+
+ setup_timer(&bcm63xx_wdt_device.timer, bcm63xx_wdt_update, 0L);
+
+ bcm63xx_wdt_device.default_ticks = ticks;
+ bcm63xx_wdt_set(ticks);
+ bcm63xx_wdt_start();
+
+ printk(KERN_INFO PFX " started, timer margin: %d sec\n", WDT_INTERVAL);
+
+ return 0;
+
+unmap:
+ iounmap(bcm63xx_wdt_device.regs);
+ return ret;
+}
+
+static int bcm63xx_wdt_remove(struct platform_device *pdev)
+{
+ if (bcm63xx_wdt_device.queue) {
+ bcm63xx_wdt_device.queue = 0;
+ wait_for_completion(&bcm63xx_wdt_device.stop);
+ }
+
+ misc_deregister(&bcm63xx_wdt_miscdev);
+
+ iounmap(bcm63xx_wdt_device.regs);
+
+ return 0;
+}
+
+static struct platform_driver bcm63xx_wdt = {
+ .probe = bcm63xx_wdt_probe,
+ .remove = bcm63xx_wdt_remove,
+ .driver = {
+ .name = "bcm63xx-wdt",
+ }
+};
+
+static int __init bcm63xx_wdt_init(void)
+{
+ return platform_driver_register(&bcm63xx_wdt);
+}
+
+static void __exit bcm63xx_wdt_exit(void)
+{
+ platform_driver_unregister(&bcm63xx_wdt);
+}
+
+module_init(bcm63xx_wdt_init);
+module_exit(bcm63xx_wdt_exit);
+
+MODULE_AUTHOR("Miguel Gaio <miguel.gaio@efixo.com>");
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("Driver for the Broadcom BCM63xx SoC watchdog");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
+MODULE_ALIAS("platform:bcm63xx-wdt");
projects / openwrt / svn-archive / archive.git / commitdiff