2 files changed, 261 insertions, 0 deletions

diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index ca3dc043d786..57c7e8bd8c88 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -122,6 +122,8 @@ obj-$(CONFIG_SH_WDT) += shwdt.o
 
 # SPARC64 Architecture
 
+obj-$(CONFIG_WATCHDOG_RIO)              += riowd.o
+
 # XTENSA Architecture
 
 # Architecture Independant
diff --git a/drivers/watchdog/riowd.c b/drivers/watchdog/riowd.c
new file mode 100644
index 000000000000..98bb60ff02f2
--- /dev/null
+++ b/drivers/watchdog/riowd.c
@@ -0,0 +1,259 @@
+/* riowd.c - driver for hw watchdog inside Super I/O of RIO
+ *
+ * Copyright (C) 2001, 2008 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/miscdevice.h>
+#include <linux/smp_lock.h>
+#include <linux/watchdog.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+
+/* RIO uses the NatSemi Super I/O power management logical device
+ * as its' watchdog.
+ *
+ * When the watchdog triggers, it asserts a line to the BBC (Boot Bus
+ * Controller) of the machine.  The BBC can only be configured to
+ * trigger a power-on reset when the signal is asserted.  The BBC
+ * can be configured to ignore the signal entirely as well.
+ *
+ * The only Super I/O device register we care about is at index
+ * 0x05 (WDTO_INDEX) which is the watchdog time-out in minutes (1-255).
+ * If set to zero, this disables the watchdog.  When set, the system
+ * must periodically (before watchdog expires) clear (set to zero) and
+ * re-set the watchdog else it will trigger.
+ *
+ * There are two other indexed watchdog registers inside this Super I/O
+ * logical device, but they are unused.  The first, at index 0x06 is
+ * the watchdog control and can be used to make the watchdog timer re-set
+ * when the PS/2 mouse or serial lines show activity.  The second, at
+ * index 0x07 is merely a sampling of the line from the watchdog to the
+ * BBC.
+ *
+ * The watchdog device generates no interrupts.
+ */
+
+MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
+MODULE_DESCRIPTION("Hardware watchdog driver for Sun RIO");
+MODULE_SUPPORTED_DEVICE("watchdog");
+MODULE_LICENSE("GPL");
+
+#define RIOWD_NAME      "pmc"
+#define PFX             RIOWD_NAME ": "
+
+struct riowd {
+        void __iomem            *regs;
+        spinlock_t              lock;
+};
+
+static struct riowd *riowd_device;
+
+#define WDTO_INDEX      0x05
+
+static int riowd_timeout = 1;           /* in minutes */
+module_param(riowd_timeout, int, 0);
+MODULE_PARM_DESC(riowd_timeout, "Watchdog timeout in minutes");
+
+static void riowd_writereg(struct riowd *p, u8 val, int index)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&p->lock, flags);
+        writeb(index, p->regs + 0);
+        writeb(val, p->regs + 1);
+        spin_unlock_irqrestore(&p->lock, flags);
+}
+
+static int riowd_open(struct inode *inode, struct file *filp)
+{
+        cycle_kernel_lock();
+        nonseekable_open(inode, filp);
+        return 0;
+}
+
+static int riowd_release(struct inode *inode, struct file *filp)
+{
+        return 0;
+}
+
+static int riowd_ioctl(struct inode *inode, struct file *filp,
+                       unsigned int cmd, unsigned long arg)
+{
+        static struct watchdog_info info = {
+                .options                = WDIOF_SETTIMEOUT,
+                .firmware_version       = 1,
+                .identity               = "riowd",
+        };
+        void __user *argp = (void __user *)arg;
+        struct riowd *p = riowd_device;
+        unsigned int options;
+        int new_margin;
+
+        switch (cmd) {
+        case WDIOC_GETSUPPORT:
+                if (copy_to_user(argp, &info, sizeof(info)))
+                        return -EFAULT;
+                break;
+
+        case WDIOC_GETSTATUS:
+        case WDIOC_GETBOOTSTATUS:
+                if (put_user(0, (int __user *)argp))
+                        return -EFAULT;
+                break;
+
+        case WDIOC_KEEPALIVE:
+                riowd_writereg(p, riowd_timeout, WDTO_INDEX);
+                break;
+
+        case WDIOC_SETOPTIONS:
+                if (copy_from_user(&options, argp, sizeof(options)))
+                        return -EFAULT;
+
+                if (options & WDIOS_DISABLECARD)
+                        riowd_writereg(p, 0, WDTO_INDEX);
+                else if (options & WDIOS_ENABLECARD)
+                        riowd_writereg(p, riowd_timeout, WDTO_INDEX);
+                else
+                        return -EINVAL;
+
+                break;
+
+        case WDIOC_SETTIMEOUT:
+                if (get_user(new_margin, (int __user *)argp))
+                        return -EFAULT;
+                if ((new_margin < 60) || (new_margin > (255 * 60)))
+                        return -EINVAL;
+                riowd_timeout = (new_margin + 59) / 60;
+                riowd_writereg(p, riowd_timeout, WDTO_INDEX);
+                /* Fall */
+
+        case WDIOC_GETTIMEOUT:
+                return put_user(riowd_timeout * 60, (int __user *)argp);
+
+        default:
+                return -EINVAL;
+        };
+
+        return 0;
+}
+
+static ssize_t riowd_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
+{
+        struct riowd *p = riowd_device;
+
+        if (count) {
+                riowd_writereg(p, riowd_timeout, WDTO_INDEX);
+                return 1;
+        }
+
+        return 0;
+}
+
+static const struct file_operations riowd_fops = {
+        .owner =        THIS_MODULE,
+        .llseek =       no_llseek,
+        .ioctl =        riowd_ioctl,
+        .open =         riowd_open,
+        .write =        riowd_write,
+        .release =      riowd_release,
+};
+
+static struct miscdevice riowd_miscdev = {
+        .minor  = WATCHDOG_MINOR,
+        .name   = "watchdog",
+        .fops   = &riowd_fops
+};
+
+static int __devinit riowd_probe(struct of_device *op,
+                                 const struct of_device_id *match)
+{
+        struct riowd *p;
+        int err = -EINVAL;
+
+        if (riowd_device)
+                goto out;
+
+        err = -ENOMEM;
+        p = kzalloc(sizeof(*p), GFP_KERNEL);
+        if (!p)
+                goto out;
+
+        spin_lock_init(&p->lock);
+
+        p->regs = of_ioremap(&op->resource[0], 0, 2, "riowd");
+        if (!p->regs) {
+                printk(KERN_ERR PFX "Cannot map registers.\n");
+                goto out_free;
+        }
+
+        err = misc_register(&riowd_miscdev);
+        if (err) {
+                printk(KERN_ERR PFX "Cannot register watchdog misc device.\n");
+                goto out_iounmap;
+        }
+
+        printk(KERN_INFO PFX "Hardware watchdog [%i minutes], "
+               "regs at %p\n", riowd_timeout, p->regs);
+
+        dev_set_drvdata(&op->dev, p);
+        riowd_device = p;
+        err = 0;
+
+out_iounmap:
+        of_iounmap(&op->resource[0], p->regs, 2);
+
+out_free:
+        kfree(p);
+
+out:
+        return err;
+}
+
+static int __devexit riowd_remove(struct of_device *op)
+{
+        struct riowd *p = dev_get_drvdata(&op->dev);
+
+        misc_deregister(&riowd_miscdev);
+        of_iounmap(&op->resource[0], p->regs, 2);
+        kfree(p);
+
+        return 0;
+}
+
+static struct of_device_id riowd_match[] = {
+        {
+                .name = "pmc",
+        },
+        {},
+};
+MODULE_DEVICE_TABLE(of, riowd_match);
+
+static struct of_platform_driver riowd_driver = {
+        .name           = "riowd",
+        .match_table    = riowd_match,
+        .probe          = riowd_probe,
+        .remove         = __devexit_p(riowd_remove),
+};
+
+static int __init riowd_init(void)
+{
+        return of_register_driver(&riowd_driver, &of_bus_type);
+}
+
+static void __exit riowd_exit(void)
+{
+        of_unregister_driver(&riowd_driver);
+}
+
+module_init(riowd_init);
+module_exit(riowd_exit);