--- /dev/null
+/*
+ * Watchdog Timer Driver
+ * for ITE IT87xx Environment Control - Low Pin Count Input / Output
+ *
+ * (c) Copyright 2007 Oliver Schuster <olivers137@aol.com>
+ *
+ * Based on softdog.c by Alan Cox,
+ * 83977f_wdt.c by Jose Goncalves,
+ * it87.c by Chris Gauthron, Jean Delvare
+ *
+ * Data-sheets: Publicly available at the ITE website
+ * http://www.ite.com.tw/
+ *
+ * Support of the watchdog timers, which are available on
+ * IT8716, IT8718, IT8726 and IT8712 (J,K version).
+ *
+ * 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/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/watchdog.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include <asm/system.h>
+
+#define WATCHDOG_VERSION "1.12"
+#define WATCHDOG_NAME "IT87 WDT"
+#define PFX WATCHDOG_NAME ": "
+#define DRIVER_VERSION WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n"
+#define WD_MAGIC 'V'
+
+/* Defaults for Module Parameter */
+#define DEFAULT_NOGAMEPORT 0
+#define DEFAULT_EXCLUSIVE 1
+#define DEFAULT_TIMEOUT 60
+#define DEFAULT_TESTMODE 0
+#define DEFAULT_NOWAYOUT WATCHDOG_NOWAYOUT
+
+/* IO Ports */
+#define REG 0x2e
+#define VAL 0x2f
+
+/* Logical device Numbers LDN */
+#define GPIO 0x07
+#define GAMEPORT 0x09
+#define CIR 0x0a
+
+/* Configuration Registers and Functions */
+#define LDNREG 0x07
+#define CHIPID 0x20
+#define CHIPREV 0x22
+#define ACTREG 0x30
+#define BASEREG 0x60
+
+/* Chip Id numbers */
+#define NO_DEV_ID 0xffff
+#define IT8705_ID 0x8705
+#define IT8712_ID 0x8712
+#define IT8716_ID 0x8716
+#define IT8718_ID 0x8718
+#define IT8726_ID 0x8726 /* the data sheet suggest wrongly 0x8716 */
+
+/* GPIO Configuration Registers LDN=0x07 */
+#define WDTCTRL 0x71
+#define WDTCFG 0x72
+#define WDTVALLSB 0x73
+#define WDTVALMSB 0x74
+
+/* GPIO Bits WDTCTRL */
+#define WDT_CIRINT 0x80
+#define WDT_MOUSEINT 0x40
+#define WDT_KYBINT 0x20
+#define WDT_GAMEPORT 0x10 /* not it8718 */
+#define WDT_FORCE 0x02
+#define WDT_ZERO 0x01
+
+/* GPIO Bits WDTCFG */
+#define WDT_TOV1 0x80
+#define WDT_KRST 0x40
+#define WDT_TOVE 0x20
+#define WDT_PWROK 0x10
+#define WDT_INT_MASK 0x0f
+
+/* CIR Configuration Register LDN=0x0a */
+#define CIR_ILS 0x70
+
+/* The default Base address is not always available, we use this */
+#define CIR_BASE 0x0208
+
+/* CIR Controller */
+#define CIR_DR(b) (b)
+#define CIR_IER(b) (b + 1)
+#define CIR_RCR(b) (b + 2)
+#define CIR_TCR1(b) (b + 3)
+#define CIR_TCR2(b) (b + 4)
+#define CIR_TSR(b) (b + 5)
+#define CIR_RSR(b) (b + 6)
+#define CIR_BDLR(b) (b + 5)
+#define CIR_BDHR(b) (b + 6)
+#define CIR_IIR(b) (b + 7)
+
+/* Default Base address of Game port */
+#define GP_BASE_DEFAULT 0x0201
+
+/* wdt_status */
+#define WDTS_TIMER_RUN 0
+#define WDTS_DEV_OPEN 1
+#define WDTS_KEEPALIVE 2
+#define WDTS_LOCKED 3
+#define WDTS_USE_GP 4
+#define WDTS_EXPECTED 5
+
+static unsigned int base, gpact, ciract;
+static unsigned long wdt_status;
+static DEFINE_SPINLOCK(spinlock);
+
+static int nogameport = DEFAULT_NOGAMEPORT;
+static int exclusive = DEFAULT_EXCLUSIVE;
+static int timeout = DEFAULT_TIMEOUT;
+static int testmode = DEFAULT_TESTMODE;
+static int nowayout = DEFAULT_NOWAYOUT;
+
+module_param(nogameport, int, 0);
+MODULE_PARM_DESC(nogameport, "Forbid the activation of game port, default="
+ __MODULE_STRING(DEFAULT_NOGAMEPORT));
+module_param(exclusive, int, 0);
+MODULE_PARM_DESC(exclusive, "Watchdog exclusive device open, default="
+ __MODULE_STRING(DEFAULT_EXCLUSIVE));
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds, default="
+ __MODULE_STRING(DEFAULT_TIMEOUT));
+module_param(testmode, int, 0);
+MODULE_PARM_DESC(testmode, "Watchdog test mode (1 = no reboot), default="
+ __MODULE_STRING(DEFAULT_TESTMODE));
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started, default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT));
+
+/* Superio Chip */
+
+static inline void superio_enter(void)
+{
+ outb(0x87, REG);
+ outb(0x01, REG);
+ outb(0x55, REG);
+ outb(0x55, REG);
+}
+
+static inline void superio_exit(void)
+{
+ outb(0x02, REG);
+ outb(0x02, VAL);
+}
+
+static inline void superio_select(int ldn)
+{
+ outb(LDNREG, REG);
+ outb(ldn, VAL);
+}
+
+static inline int superio_inb(int reg)
+{
+ outb(reg, REG);
+ return inb(VAL);
+}
+
+static inline void superio_outb(int val, int reg)
+{
+ outb(reg, REG);
+ outb(val, VAL);
+}
+
+static inline int superio_inw(int reg)
+{
+ int val;
+ outb(reg++, REG);
+ val = inb(VAL) << 8;
+ outb(reg, REG);
+ val |= inb(VAL);
+ return val;
+}
+
+static inline void superio_outw(int val, int reg)
+{
+ outb(reg++, REG);
+ outb(val >> 8, VAL);
+ outb(reg, REG);
+ outb(val, VAL);
+}
+
+/* watchdog timer handling */
+
+static void wdt_keepalive(void)
+{
+ if (test_bit(WDTS_USE_GP, &wdt_status))
+ inb(base);
+ else
+ /* The timer reloads with around 5 msec delay */
+ outb(0x55, CIR_DR(base));
+ set_bit(WDTS_KEEPALIVE, &wdt_status);
+}
+
+static void wdt_start(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+
+ superio_select(GPIO);
+ if (test_bit(WDTS_USE_GP, &wdt_status))
+ superio_outb(WDT_GAMEPORT, WDTCTRL);
+ else
+ superio_outb(WDT_CIRINT, WDTCTRL);
+ if (!testmode)
+ superio_outb(WDT_TOV1 | WDT_KRST | WDT_PWROK, WDTCFG);
+ else
+ superio_outb(WDT_TOV1, WDTCFG);
+ superio_outb(timeout>>8, WDTVALMSB);
+ superio_outb(timeout, WDTVALLSB);
+
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+}
+
+static void wdt_stop(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+
+ superio_select(GPIO);
+ superio_outb(0x00, WDTCTRL);
+ superio_outb(WDT_TOV1, WDTCFG);
+ superio_outb(0x00, WDTVALMSB);
+ superio_outb(0x00, WDTVALLSB);
+
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+}
+
+/**
+ * wdt_set_timeout - set a new timeout value with watchdog ioctl
+ * @t: timeout value in seconds
+ *
+ * The hardware device has a 16 bit watchdog timer, thus the
+ * timeout time ranges between 1 and 65535 seconds.
+ *
+ * Used within WDIOC_SETTIMEOUT watchdog device ioctl.
+ */
+
+static int wdt_set_timeout(int t)
+{
+ unsigned long flags;
+
+ if (t < 1 || t > 65535)
+ return -EINVAL;
+
+ timeout = t;
+
+ spin_lock_irqsave(&spinlock, flags);
+ if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
+ superio_enter();
+
+ superio_select(GPIO);
+ superio_outb(t>>8, WDTVALMSB);
+ superio_outb(t, WDTVALLSB);
+
+ superio_exit();
+ }
+ spin_unlock_irqrestore(&spinlock, flags);
+ return 0;
+}
+
+/**
+ * wdt_get_status - determines the status supported by watchdog ioctl
+ * @status: status returned to user space
+ *
+ * The status bit of the device does not allow to distinguish
+ * between a regular system reset and a watchdog forced reset.
+ * But, in test mode it is useful, so it is supported through
+ * WDIOC_GETSTATUS watchdog ioctl. Additionally the driver
+ * reports the keepalive signal and the acception of the magic.
+ *
+ * Used within WDIOC_GETSTATUS watchdog device ioctl.
+ */
+
+static int wdt_get_status(int *status)
+{
+ unsigned long flags;
+
+ *status = 0;
+ if (testmode) {
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+ superio_select(GPIO);
+ if (superio_inb(WDTCTRL) & WDT_ZERO) {
+ superio_outb(0x00, WDTCTRL);
+ clear_bit(WDTS_TIMER_RUN, &wdt_status);
+ *status |= WDIOF_CARDRESET;
+ }
+
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+ }
+ if (test_and_clear_bit(WDTS_KEEPALIVE, &wdt_status))
+ *status |= WDIOF_KEEPALIVEPING;
+ if (test_bit(WDTS_EXPECTED, &wdt_status))
+ *status |= WDIOF_MAGICCLOSE;
+ return 0;
+}
+
+/* /dev/watchdog handling */
+
+/**
+ * wdt_open - watchdog file_operations .open
+ * @inode: inode of the device
+ * @file: file handle to the device
+ *
+ * The watchdog timer starts by opening the device.
+ *
+ * Used within the file operation of the watchdog device.
+ */
+
+static int wdt_open(struct inode *inode, struct file *file)
+{
+ if (exclusive && test_and_set_bit(WDTS_DEV_OPEN, &wdt_status))
+ return -EBUSY;
+ if (!test_and_set_bit(WDTS_TIMER_RUN, &wdt_status)) {
+ if (nowayout && !test_and_set_bit(WDTS_LOCKED, &wdt_status))
+ __module_get(THIS_MODULE);
+ wdt_start();
+ }
+ return nonseekable_open(inode, file);
+}
+
+/**
+ * wdt_release - watchdog file_operations .release
+ * @inode: inode of the device
+ * @file: file handle to the device
+ *
+ * Closing the watchdog device either stops the watchdog timer
+ * or in the case, that nowayout is set or the magic character
+ * wasn't written, a critical warning about an running watchdog
+ * timer is given.
+ *
+ * Used within the file operation of the watchdog device.
+ */
+
+static int wdt_release(struct inode *inode, struct file *file)
+{
+ if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
+ if (test_and_clear_bit(WDTS_EXPECTED, &wdt_status)) {
+ wdt_stop();
+ clear_bit(WDTS_TIMER_RUN, &wdt_status);
+ } else {
+ wdt_keepalive();
+ printk(KERN_CRIT PFX
+ "unexpected close, not stopping watchdog!\n");
+ }
+ }
+ clear_bit(WDTS_DEV_OPEN, &wdt_status);
+ return 0;
+}
+
+/**
+ * wdt_write - watchdog file_operations .write
+ * @file: file handle to the watchdog
+ * @buf: buffer to write
+ * @count: count of bytes
+ * @ppos: pointer to the position to write. No seeks allowed
+ *
+ * A write to a watchdog device is defined as a keepalive signal. Any
+ * write of data will do, as we don't define content meaning.
+ *
+ * Used within the file operation of the watchdog device.
+ */
+
+static ssize_t wdt_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ if (count) {
+ clear_bit(WDTS_EXPECTED, &wdt_status);
+ wdt_keepalive();
+ }
+ if (!nowayout) {
+ size_t ofs;
+
+ /* note: just in case someone wrote the magic character long ago */
+ for (ofs = 0; ofs != count; ofs++) {
+ char c;
+ if (get_user(c, buf + ofs))
+ return -EFAULT;
+ if (c == WD_MAGIC)
+ set_bit(WDTS_EXPECTED, &wdt_status);
+ }
+ }
+ return count;
+}
+
+static struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
+ .firmware_version = 1,
+ .identity = WATCHDOG_NAME,
+};
+
+/**
+ * wdt_ioctl - watchdog file_operations .unlocked_ioctl
+ * @file: file handle to the device
+ * @cmd: watchdog command
+ * @arg: argument pointer
+ *
+ * The watchdog API defines a common set of functions for all watchdogs
+ * according to their available features.
+ *
+ * Used within the file operation of the watchdog device.
+ */
+
+static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int rc = 0, status, new_options, new_timeout;
+ union {
+ struct watchdog_info __user *ident;
+ int __user *i;
+ } uarg;
+
+ uarg.i = (int __user *)arg;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return copy_to_user(uarg.ident,
+ &ident, sizeof(ident)) ? -EFAULT : 0;
+
+ case WDIOC_GETSTATUS:
+ wdt_get_status(&status);
+ return put_user(status, uarg.i);
+
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, uarg.i);
+
+ case WDIOC_KEEPALIVE:
+ wdt_keepalive();
+ return 0;
+
+ case WDIOC_SETOPTIONS:
+ if (get_user(new_options, uarg.i))
+ return -EFAULT;
+
+ switch (new_options) {
+ case WDIOS_DISABLECARD:
+ if (test_bit(WDTS_TIMER_RUN, &wdt_status))
+ wdt_stop();
+ clear_bit(WDTS_TIMER_RUN, &wdt_status);
+ return 0;
+
+ case WDIOS_ENABLECARD:
+ if (!test_and_set_bit(WDTS_TIMER_RUN, &wdt_status))
+ wdt_start();
+ return 0;
+
+ default:
+ return -EFAULT;
+ }
+
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_timeout, uarg.i))
+ return -EFAULT;
+ rc = wdt_set_timeout(new_timeout);
+ case WDIOC_GETTIMEOUT:
+ if (put_user(timeout, uarg.i))
+ return -EFAULT;
+ return rc;
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ if (code == SYS_DOWN || code == SYS_HALT)
+ wdt_stop();
+ return NOTIFY_DONE;
+}
+
+static const struct file_operations wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = wdt_write,
+ .unlocked_ioctl = wdt_ioctl,
+ .open = wdt_open,
+ .release = wdt_release,
+};
+
+static struct miscdevice wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &wdt_fops,
+};
+
+static struct notifier_block wdt_notifier = {
+ .notifier_call = wdt_notify_sys,
+};
+
+static int __init it87_wdt_init(void)
+{
+ int rc = 0;
+ u16 chip_type;
+ u8 chip_rev;
+ unsigned long flags;
+
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+ chip_type = superio_inw(CHIPID);
+ chip_rev = superio_inb(CHIPREV) & 0x0f;
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+
+ switch (chip_type) {
+ case IT8716_ID:
+ case IT8718_ID:
+ case IT8726_ID:
+ break;
+ case IT8712_ID:
+ if (chip_rev > 7)
+ break;
+ case IT8705_ID:
+ printk(KERN_ERR PFX
+ "Unsupported Chip found, Chip %04x Revision %02x\n",
+ chip_type, chip_rev);
+ return -ENODEV;
+ case NO_DEV_ID:
+ printk(KERN_ERR PFX "no device\n");
+ return -ENODEV;
+ default:
+ printk(KERN_ERR PFX
+ "Unknown Chip found, Chip %04x Revision %04x\n",
+ chip_type, chip_rev);
+ return -ENODEV;
+ }
+
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+
+ superio_select(GPIO);
+ superio_outb(WDT_TOV1, WDTCFG);
+ superio_outb(0x00, WDTCTRL);
+
+ /* First try to get Gameport support */
+ if (chip_type != IT8718_ID && !nogameport) {
+ superio_select(GAMEPORT);
+ base = superio_inw(BASEREG);
+ if (!base) {
+ base = GP_BASE_DEFAULT;
+ superio_outw(base, BASEREG);
+ }
+ gpact = superio_inb(ACTREG);
+ superio_outb(0x01, ACTREG);
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+ if (request_region(base, 1, WATCHDOG_NAME))
+ set_bit(WDTS_USE_GP, &wdt_status);
+ else
+ rc = -EIO;
+ } else {
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+ }
+
+ /* If we haven't Gameport support, try to get CIR support */
+ if (!test_bit(WDTS_USE_GP, &wdt_status)) {
+ if (!request_region(CIR_BASE, 8, WATCHDOG_NAME)) {
+ if (rc == -EIO)
+ printk(KERN_ERR PFX
+ "I/O Address 0x%04x and 0x%04x"
+ " already in use\n", base, CIR_BASE);
+ else
+ printk(KERN_ERR PFX
+ "I/O Address 0x%04x already in use\n",
+ CIR_BASE);
+ rc = -EIO;
+ goto err_out;
+ }
+ base = CIR_BASE;
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+
+ superio_select(CIR);
+ superio_outw(base, BASEREG);
+ superio_outb(0x00, CIR_ILS);
+ ciract = superio_inb(ACTREG);
+ superio_outb(0x01, ACTREG);
+ if (rc == -EIO) {
+ superio_select(GAMEPORT);
+ superio_outb(gpact, ACTREG);
+ }
+
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+ }
+
+ if (timeout < 1 || timeout > 65535) {
+ timeout = DEFAULT_TIMEOUT;
+ printk(KERN_WARNING PFX
+ "Timeout value out of range, use default %d sec\n",
+ DEFAULT_TIMEOUT);
+ }
+
+ rc = register_reboot_notifier(&wdt_notifier);
+ if (rc) {
+ printk(KERN_ERR PFX
+ "Cannot register reboot notifier (err=%d)\n", rc);
+ goto err_out_region;
+ }
+
+ rc = misc_register(&wdt_miscdev);
+ if (rc) {
+ printk(KERN_ERR PFX
+ "Cannot register miscdev on minor=%d (err=%d)\n",
+ wdt_miscdev.minor, rc);
+ goto err_out_reboot;
+ }
+
+ /* Initialize CIR to use it as keepalive source */
+ if (!test_bit(WDTS_USE_GP, &wdt_status)) {
+ outb(0x00, CIR_RCR(base));
+ outb(0xc0, CIR_TCR1(base));
+ outb(0x5c, CIR_TCR2(base));
+ outb(0x10, CIR_IER(base));
+ outb(0x00, CIR_BDHR(base));
+ outb(0x01, CIR_BDLR(base));
+ outb(0x09, CIR_IER(base));
+ }
+
+ printk(KERN_INFO PFX "Chip it%04x revision %d initialized. "
+ "timeout=%d sec (nowayout=%d testmode=%d exclusive=%d "
+ "nogameport=%d)\n", chip_type, chip_rev, timeout,
+ nowayout, testmode, exclusive, nogameport);
+
+ return 0;
+
+err_out_reboot:
+ unregister_reboot_notifier(&wdt_notifier);
+err_out_region:
+ release_region(base, test_bit(WDTS_USE_GP, &wdt_status) ? 1 : 8);
+ if (!test_bit(WDTS_USE_GP, &wdt_status)) {
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+ superio_select(CIR);
+ superio_outb(ciract, ACTREG);
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+ }
+err_out:
+ if (chip_type != IT8718_ID && !nogameport) {
+ spin_lock_irqsave(&spinlock, flags);
+ superio_enter();
+ superio_select(GAMEPORT);
+ superio_outb(gpact, ACTREG);
+ superio_exit();
+ spin_unlock_irqrestore(&spinlock, flags);
+ }
+
+ return rc;
+}
+
+static void __exit it87_wdt_exit(void)
+{
+ unsigned long flags;
+ int nolock;
+
+ nolock = !spin_trylock_irqsave(&spinlock, flags);
+ superio_enter();
+ superio_select(GPIO);
+ superio_outb(0x00, WDTCTRL);
+ superio_outb(0x00, WDTCFG);
+ superio_outb(0x00, WDTVALMSB);
+ superio_outb(0x00, WDTVALLSB);
+ if (test_bit(WDTS_USE_GP, &wdt_status)) {
+ superio_select(GAMEPORT);
+ superio_outb(gpact, ACTREG);
+ } else {
+ superio_select(CIR);
+ superio_outb(ciract, ACTREG);
+ }
+ superio_exit();
+ if (!nolock)
+ spin_unlock_irqrestore(&spinlock, flags);
+
+ misc_deregister(&wdt_miscdev);
+ unregister_reboot_notifier(&wdt_notifier);
+ release_region(base, test_bit(WDTS_USE_GP, &wdt_status) ? 1 : 8);
+}
+
+module_init(it87_wdt_init);
+module_exit(it87_wdt_exit);
+
+MODULE_AUTHOR("Oliver Schuster");
+MODULE_DESCRIPTION("Hardware Watchdog Device Driver for IT87xx EC-LPC I/O");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
projects / karo-tx-linux.git / commitdiff