1 files changed, 465 insertions, 0 deletions

diff --git a/drivers/watchdog/alim1535_wdt.c b/drivers/watchdog/alim1535_wdt.c
new file mode 100644
index 000000000000..c404fc69e7e6
--- /dev/null
+++ b/drivers/watchdog/alim1535_wdt.c
@@ -0,0 +1,465 @@
+/*
+ *      Watchdog for the 7101 PMU version found in the ALi M1535 chipsets
+ *
+ *      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/moduleparam.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/ioport.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/pci.h>
+
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+#define WATCHDOG_NAME "ALi_M1535"
+#define PFX WATCHDOG_NAME ": "
+#define WATCHDOG_TIMEOUT 60     /* 60 sec default timeout */
+
+/* internal variables */
+static unsigned long ali_is_open;
+static char ali_expect_release;
+static struct pci_dev *ali_pci;
+static u32 ali_timeout_bits;    /* stores the computed timeout */
+static spinlock_t ali_lock;     /* Guards the hardware */
+
+/* module parameters */
+static int timeout = WATCHDOG_TIMEOUT;
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (0<timeout<18000, default=" __MODULE_STRING(WATCHDOG_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) ")");
+
+/*
+ *      ali_start       -       start watchdog countdown
+ *
+ *      Starts the timer running providing the timer has a counter
+ *      configuration set.
+ */
+
+static void ali_start(void)
+{
+        u32 val;
+
+        spin_lock(&ali_lock);
+
+        pci_read_config_dword(ali_pci, 0xCC, &val);
+        val &= ~0x3F;   /* Mask count */
+        val |= (1<<25) | ali_timeout_bits;
+        pci_write_config_dword(ali_pci, 0xCC, val);
+
+        spin_unlock(&ali_lock);
+}
+
+/*
+ *      ali_stop        -       stop the timer countdown
+ *
+ *      Stop the ALi watchdog countdown
+ */
+
+static void ali_stop(void)
+{
+        u32 val;
+
+        spin_lock(&ali_lock);
+
+        pci_read_config_dword(ali_pci, 0xCC, &val);
+        val &= ~0x3F;   /* Mask count to zero (disabled) */
+        val &= ~(1<<25);/* and for safety mask the reset enable */
+        pci_write_config_dword(ali_pci, 0xCC, val);
+
+        spin_unlock(&ali_lock);
+}
+
+/*
+ *      ali_keepalive   -       send a keepalive to the watchdog
+ *
+ *      Send a keepalive to the timer (actually we restart the timer).
+ */
+
+static void ali_keepalive(void)
+{
+        ali_start();
+}
+
+/*
+ *      ali_settimer    -       compute the timer reload value
+ *      @t: time in seconds
+ *
+ *      Computes the timeout values needed
+ */
+
+static int ali_settimer(int t)
+{
+        if(t < 0)
+                return -EINVAL;
+        else if(t < 60)
+                ali_timeout_bits = t|(1<<6);
+        else if(t < 3600)
+                ali_timeout_bits = (t/60)|(1<<7);
+        else if(t < 18000)
+                ali_timeout_bits = (t/300)|(1<<6)|(1<<7);
+        else return -EINVAL;
+
+        timeout = t;
+        return 0;
+}
+
+/*
+ *      /dev/watchdog handling
+ */
+
+/*
+ *      ali_write       -       writes to ALi watchdog
+ *      @file: file from VFS
+ *      @data: user address of data
+ *      @len: length of data
+ *      @ppos: pointer to the file offset
+ *
+ *      Handle a write to the ALi watchdog. Writing to the file pings
+ *      the watchdog and resets it. Writing the magic 'V' sequence allows
+ *      the next close to turn off the watchdog.
+ */
+
+static ssize_t ali_write(struct file *file, const char __user *data,
+                              size_t len, loff_t * ppos)
+{
+        /* See if we got the magic character 'V' and reload the timer */
+        if (len) {
+                if (!nowayout) {
+                        size_t i;
+
+                        /* note: just in case someone wrote the magic character
+                         * five months ago... */
+                        ali_expect_release = 0;
+
+                        /* scan to see whether or not we got the magic character */
+                        for (i = 0; i != len; i++) {
+                                char c;
+                                if(get_user(c, data+i))
+                                        return -EFAULT;
+                                if (c == 'V')
+                                        ali_expect_release = 42;
+                        }
+                }
+
+                /* someone wrote to us, we should reload the timer */
+                ali_start();
+        }
+        return len;
+}
+
+/*
+ *      ali_ioctl       -       handle watchdog ioctls
+ *      @inode: VFS inode
+ *      @file: VFS file pointer
+ *      @cmd: ioctl number
+ *      @arg: arguments to the ioctl
+ *
+ *      Handle the watchdog ioctls supported by the ALi driver. Really
+ *      we want an extension to enable irq ack monitoring and the like
+ */
+
+static int ali_ioctl(struct inode *inode, struct file *file,
+                          unsigned int cmd, unsigned long arg)
+{
+        void __user *argp = (void __user *)arg;
+        int __user *p = argp;
+        static struct watchdog_info ident = {
+                .options =              WDIOF_KEEPALIVEPING |
+                                        WDIOF_SETTIMEOUT |
+                                        WDIOF_MAGICCLOSE,
+                .firmware_version =     0,
+                .identity =             "ALi M1535 WatchDog Timer",
+        };
+
+        switch (cmd) {
+                case WDIOC_GETSUPPORT:
+                        return copy_to_user(argp, &ident,
+                                sizeof (ident)) ? -EFAULT : 0;
+
+                case WDIOC_GETSTATUS:
+                case WDIOC_GETBOOTSTATUS:
+                        return put_user(0, p);
+
+                case WDIOC_KEEPALIVE:
+                        ali_keepalive();
+                        return 0;
+
+                case WDIOC_SETOPTIONS:
+                {
+                        int new_options, retval = -EINVAL;
+
+                        if (get_user (new_options, p))
+                                return -EFAULT;
+
+                        if (new_options & WDIOS_DISABLECARD) {
+                                ali_stop();
+                                retval = 0;
+                        }
+
+                        if (new_options & WDIOS_ENABLECARD) {
+                                ali_start();
+                                retval = 0;
+                        }
+
+                        return retval;
+                }
+
+                case WDIOC_SETTIMEOUT:
+                {
+                        int new_timeout;
+
+                        if (get_user(new_timeout, p))
+                                return -EFAULT;
+
+                        if (ali_settimer(new_timeout))
+                            return -EINVAL;
+
+                        ali_keepalive();
+                        /* Fall */
+                }
+
+                case WDIOC_GETTIMEOUT:
+                        return put_user(timeout, p);
+
+                default:
+                        return -ENOTTY;
+        }
+}
+
+/*
+ *      ali_open        -       handle open of ali watchdog
+ *      @inode: inode from VFS
+ *      @file: file from VFS
+ *
+ *      Open the ALi watchdog device. Ensure only one person opens it
+ *      at a time. Also start the watchdog running.
+ */
+
+static int ali_open(struct inode *inode, struct file *file)
+{
+        /* /dev/watchdog can only be opened once */
+        if (test_and_set_bit(0, &ali_is_open))
+                return -EBUSY;
+
+        /* Activate */
+        ali_start();
+        return nonseekable_open(inode, file);
+}
+
+/*
+ *      ali_release     -       close an ALi watchdog
+ *      @inode: inode from VFS
+ *      @file: file from VFS
+ *
+ *      Close the ALi watchdog device. Actual shutdown of the timer
+ *      only occurs if the magic sequence has been set.
+ */
+
+static int ali_release(struct inode *inode, struct file *file)
+{
+        /*
+         *      Shut off the timer.
+         */
+        if (ali_expect_release == 42) {
+                ali_stop();
+        } else {
+                printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
+                ali_keepalive();
+        }
+        clear_bit(0, &ali_is_open);
+        ali_expect_release = 0;
+        return 0;
+}
+
+/*
+ *      ali_notify_sys  -       System down notifier
+ *
+ *      Notifier for system down
+ */
+
+
+static int ali_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
+{
+        if (code==SYS_DOWN || code==SYS_HALT) {
+                /* Turn the WDT off */
+                ali_stop();
+        }
+
+        return NOTIFY_DONE;
+}
+
+/*
+ *      Data for PCI driver interface
+ *
+ *      This data only exists for exporting the supported
+ *      PCI ids via MODULE_DEVICE_TABLE.  We do not actually
+ *      register a pci_driver, because someone else might one day
+ *      want to register another driver on the same PCI id.
+ */
+
+static struct pci_device_id ali_pci_tbl[] = {
+        { PCI_VENDOR_ID_AL, 0x1533, PCI_ANY_ID, PCI_ANY_ID,},
+        { PCI_VENDOR_ID_AL, 0x1535, PCI_ANY_ID, PCI_ANY_ID,},
+        { 0, },
+};
+MODULE_DEVICE_TABLE(pci, ali_pci_tbl);
+
+/*
+ *      ali_find_watchdog       -       find a 1535 and 7101
+ *
+ *      Scans the PCI hardware for a 1535 series bridge and matching 7101
+ *      watchdog device. This may be overtight but it is better to be safe
+ */
+
+static int __init ali_find_watchdog(void)
+{
+        struct pci_dev *pdev;
+        u32 wdog;
+
+        /* Check for a 1533/1535 series bridge */
+        pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1535, NULL);
+        if (pdev == NULL)
+                pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1533, NULL);
+        if (pdev == NULL)
+                return -ENODEV;
+        pci_dev_put(pdev);
+
+        /* Check for the a 7101 PMU */
+        pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x7101, NULL);
+        if(pdev == NULL)
+                return -ENODEV;
+
+        if(pci_enable_device(pdev)) {
+                pci_dev_put(pdev);
+                return -EIO;
+        }
+
+        ali_pci = pdev;
+
+        /*
+         *      Initialize the timer bits
+         */
+        pci_read_config_dword(pdev, 0xCC, &wdog);
+
+        wdog &= ~0x3F;          /* Timer bits */
+        wdog &= ~((1<<27)|(1<<26)|(1<<25)|(1<<24));     /* Issued events */
+        wdog &= ~((1<<16)|(1<<13)|(1<<12)|(1<<11)|(1<<10)|(1<<9));      /* No monitor bits */
+
+        pci_write_config_dword(pdev, 0xCC, wdog);
+
+        return 0;
+}
+
+/*
+ *      Kernel Interfaces
+ */
+
+static const struct file_operations ali_fops = {
+        .owner =        THIS_MODULE,
+        .llseek =       no_llseek,
+        .write =        ali_write,
+        .ioctl =        ali_ioctl,
+        .open =         ali_open,
+        .release =      ali_release,
+};
+
+static struct miscdevice ali_miscdev = {
+        .minor =        WATCHDOG_MINOR,
+        .name =         "watchdog",
+        .fops =         &ali_fops,
+};
+
+static struct notifier_block ali_notifier = {
+        .notifier_call =        ali_notify_sys,
+};
+
+/*
+ *      watchdog_init   -       module initialiser
+ *
+ *      Scan for a suitable watchdog and if so initialize it. Return an error
+ *      if we cannot, the error causes the module to unload
+ */
+
+static int __init watchdog_init(void)
+{
+        int ret;
+
+        spin_lock_init(&ali_lock);
+
+        /* Check whether or not the hardware watchdog is there */
+        if (ali_find_watchdog() != 0) {
+                return -ENODEV;
+        }
+
+        /* Check that the timeout value is within it's range ; if not reset to the default */
+        if (timeout < 1 || timeout >= 18000) {
+                timeout = WATCHDOG_TIMEOUT;
+                printk(KERN_INFO PFX "timeout value must be 0<timeout<18000, using %d\n",
+                        timeout);
+        }
+
+        /* Calculate the watchdog's timeout */
+        ali_settimer(timeout);
+
+        ret = misc_register(&ali_miscdev);
+        if (ret != 0) {
+                printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
+                        WATCHDOG_MINOR, ret);
+                goto out;
+        }
+
+        ret = register_reboot_notifier(&ali_notifier);
+        if (ret != 0) {
+                printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
+                        ret);
+                goto unreg_miscdev;
+        }
+
+        printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
+                timeout, nowayout);
+
+out:
+        return ret;
+unreg_miscdev:
+        misc_deregister(&ali_miscdev);
+        goto out;
+}
+
+/*
+ *      watchdog_exit   -       module de-initialiser
+ *
+ *      Called while unloading a successfully installed watchdog module.
+ */
+
+static void __exit watchdog_exit(void)
+{
+        /* Stop the timer before we leave */
+        ali_stop();
+
+        /* Deregister */
+        unregister_reboot_notifier(&ali_notifier);
+        misc_deregister(&ali_miscdev);
+        pci_dev_put(ali_pci);
+}
+
+module_init(watchdog_init);
+module_exit(watchdog_exit);
+
+MODULE_AUTHOR("Alan Cox");
+MODULE_DESCRIPTION("ALi M1535 PMU Watchdog Timer driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);