watchdog: it87: Convert to use watchdog core infrastructure
authorGuenter Roeck <linux@roeck-us.net>
Sun, 11 Jun 2017 04:04:33 +0000 (21:04 -0700)
committerWim Van Sebroeck <wim@iguana.be>
Mon, 3 Jul 2017 08:58:47 +0000 (10:58 +0200)
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/watchdog/Kconfig
drivers/watchdog/it87_wdt.c

index e9da196..d347bb2 100644 (file)
@@ -1069,6 +1069,7 @@ config IT8712F_WDT
 config IT87_WDT
        tristate "IT87 Watchdog Timer"
        depends on X86
+       select WATCHDOG_CORE
        ---help---
          This is the driver for the hardware watchdog on the ITE IT8620,
          IT8702, IT8712, IT8716, IT8718, IT8720, IT8721, IT8726 and IT8728
index 8c847f8..9a6523e 100644 (file)
 #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>
 
-
-#define WATCHDOG_VERSION       "1.14"
 #define WATCHDOG_NAME          "IT87 WDT"
-#define DRIVER_VERSION         WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n"
-#define WD_MAGIC               'V'
 
 /* Defaults for Module Parameter */
 #define DEFAULT_NOGAMEPORT     0
 #define DEFAULT_NOCIR          0
-#define DEFAULT_EXCLUSIVE      1
 #define DEFAULT_TIMEOUT                60
 #define DEFAULT_TESTMODE       0
 #define DEFAULT_NOWAYOUT       WATCHDOG_NOWAYOUT
 #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
-#define WDTS_USE_CIR   6
-
-static unsigned int base, gpact, ciract, max_units, chip_type;
-static unsigned long wdt_status;
-
-static int nogameport = DEFAULT_NOGAMEPORT;
-static int nocir      = DEFAULT_NOCIR;
-static int exclusive  = DEFAULT_EXCLUSIVE;
-static int timeout    = DEFAULT_TIMEOUT;
-static int testmode   = DEFAULT_TESTMODE;
-static bool nowayout   = DEFAULT_NOWAYOUT;
+#define WDTS_USE_GP    0
+#define WDTS_USE_CIR   1
+
+static unsigned int base, gpact, ciract, max_units, chip_type;
+static unsigned long wdt_status;
+
+static int nogameport  = DEFAULT_NOGAMEPORT;
+static int nocir       = DEFAULT_NOCIR;
+static unsigned int timeout = DEFAULT_TIMEOUT;
+static int testmode    = DEFAULT_TESTMODE;
+static bool nowayout    = DEFAULT_NOWAYOUT;
 
 module_param(nogameport, int, 0);
 MODULE_PARM_DESC(nogameport, "Forbid the activation of game port, default="
@@ -153,9 +139,6 @@ MODULE_PARM_DESC(nogameport, "Forbid the activation of game port, default="
 module_param(nocir, int, 0);
 MODULE_PARM_DESC(nocir, "Forbid the use of Consumer IR interrupts to reset timer, default="
                __MODULE_STRING(DEFAULT_NOCIR));
-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));
@@ -227,7 +210,7 @@ static inline void superio_outw(int val, int reg)
 }
 
 /* Internal function, should be called after superio_select(GPIO) */
-static void wdt_update_timeout(void)
+static void _wdt_update_timeout(void)
 {
        unsigned char cfg = WDT_KRST;
        int tm = timeout;
@@ -249,6 +232,21 @@ static void wdt_update_timeout(void)
                superio_outb(tm>>8, WDTVALMSB);
 }
 
+static int wdt_update_timeout(void)
+{
+       int ret;
+
+       ret = superio_enter();
+       if (ret)
+               return ret;
+
+       superio_select(GPIO);
+       _wdt_update_timeout();
+       superio_exit();
+
+       return 0;
+}
+
 static int wdt_round_time(int t)
 {
        t += 59;
@@ -258,25 +256,22 @@ static int wdt_round_time(int t)
 
 /* watchdog timer handling */
 
-static void wdt_keepalive(void)
+static int wdt_keepalive(struct watchdog_device *wdd)
 {
+       int ret = 0;
+
        if (test_bit(WDTS_USE_GP, &wdt_status))
                inb(base);
        else if (test_bit(WDTS_USE_CIR, &wdt_status))
                /* The timer reloads with around 5 msec delay */
                outb(0x55, CIR_DR(base));
-       else {
-               if (superio_enter())
-                       return;
+       else
+               ret = wdt_update_timeout();
 
-               superio_select(GPIO);
-               wdt_update_timeout();
-               superio_exit();
-       }
-       set_bit(WDTS_KEEPALIVE, &wdt_status);
+       return ret;
 }
 
-static int wdt_start(void)
+static int wdt_start(struct watchdog_device *wdd)
 {
        int ret = superio_enter();
        if (ret)
@@ -287,14 +282,15 @@ static int wdt_start(void)
                superio_outb(WDT_GAMEPORT, WDTCTRL);
        else if (test_bit(WDTS_USE_CIR, &wdt_status))
                superio_outb(WDT_CIRINT, WDTCTRL);
-       wdt_update_timeout();
+
+       _wdt_update_timeout();
 
        superio_exit();
 
        return 0;
 }
 
-static int wdt_stop(void)
+static int wdt_stop(struct watchdog_device *wdd)
 {
        int ret = superio_enter();
        if (ret)
@@ -321,280 +317,49 @@ static int wdt_stop(void)
  *     Used within WDIOC_SETTIMEOUT watchdog device ioctl.
  */
 
-static int wdt_set_timeout(int t)
+static int wdt_set_timeout(struct watchdog_device *wdd, unsigned int t)
 {
-       if (t < 1 || t > max_units * 60)
-               return -EINVAL;
+       int ret = 0;
 
        if (t > max_units)
-               timeout = wdt_round_time(t);
-       else
-               timeout = t;
-
-       if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
-               int ret = superio_enter();
-               if (ret)
-                       return ret;
-
-               superio_select(GPIO);
-               wdt_update_timeout();
-               superio_exit();
-       }
-       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)
-{
-       *status = 0;
-       if (testmode) {
-               int ret = superio_enter();
-               if (ret)
-                       return ret;
-
-               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();
-       }
-       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)) {
-               int ret;
-               if (nowayout && !test_and_set_bit(WDTS_LOCKED, &wdt_status))
-                       __module_get(THIS_MODULE);
-
-               ret = wdt_start();
-               if (ret) {
-                       clear_bit(WDTS_LOCKED, &wdt_status);
-                       clear_bit(WDTS_TIMER_RUN, &wdt_status);
-                       clear_bit(WDTS_DEV_OPEN, &wdt_status);
-                       return ret;
-               }
-       }
-       return nonseekable_open(inode, file);
-}
+               t = wdt_round_time(t);
 
-/**
- *     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.
- */
+       wdd->timeout = t;
 
-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)) {
-                       int ret = wdt_stop();
-                       if (ret) {
-                               /*
-                                * Stop failed. Just keep the watchdog alive
-                                * and hope nothing bad happens.
-                                */
-                               set_bit(WDTS_EXPECTED, &wdt_status);
-                               wdt_keepalive();
-                               return ret;
-                       }
-                       clear_bit(WDTS_TIMER_RUN, &wdt_status);
-               } else {
-                       wdt_keepalive();
-                       pr_crit("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.
- */
+       if (watchdog_hw_running(wdd))
+               ret = wdt_update_timeout();
 
-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;
+       return ret;
 }
 
 static const struct watchdog_info ident = {
        .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
-       .firmware_version =     1,
+       .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:
-               rc = wdt_get_status(&status);
-               if (rc)
-                       return rc;
-               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)) {
-                               rc = wdt_stop();
-                               if (rc)
-                                       return rc;
-                       }
-                       clear_bit(WDTS_TIMER_RUN, &wdt_status);
-                       return 0;
-
-               case WDIOS_ENABLECARD:
-                       if (!test_and_set_bit(WDTS_TIMER_RUN, &wdt_status)) {
-                               rc = wdt_start();
-                               if (rc) {
-                                       clear_bit(WDTS_TIMER_RUN, &wdt_status);
-                                       return rc;
-                               }
-                       }
-                       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;
+static struct watchdog_ops wdt_ops = {
+       .owner = THIS_MODULE,
+       .start = wdt_start,
+       .stop = wdt_stop,
+       .ping = wdt_keepalive,
+       .set_timeout = wdt_set_timeout,
+};
 
-       default:
-               return -ENOTTY;
-       }
-}
+static struct watchdog_device wdt_dev = {
+       .info = &ident,
+       .ops = &wdt_ops,
+       .min_timeout = 1,
+};
 
 static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
-       void *unused)
+                         void *unused)
 {
        if (code == SYS_DOWN || code == SYS_HALT)
-               wdt_stop();
+               wdt_stop(&wdt_dev);
        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,
 };
@@ -708,19 +473,15 @@ static int __init it87_wdt_init(void)
        if (timeout > max_units)
                timeout = wdt_round_time(timeout);
 
+       wdt_dev.timeout = timeout;
+       wdt_dev.max_timeout = max_units * 60;
+
        rc = register_reboot_notifier(&wdt_notifier);
        if (rc) {
                pr_err("Cannot register reboot notifier (err=%d)\n", rc);
                goto err_out_region;
        }
 
-       rc = misc_register(&wdt_miscdev);
-       if (rc) {
-               pr_err("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_CIR, &wdt_status)) {
                outb(0x00, CIR_RCR(base));
@@ -732,9 +493,15 @@ static int __init it87_wdt_init(void)
                outb(0x09, CIR_IER(base));
        }
 
-       pr_info("Chip IT%04x revision %d initialized. timeout=%d sec (nowayout=%d testmode=%d exclusive=%d nogameport=%d nocir=%d)\n",
+       rc = watchdog_register_device(&wdt_dev);
+       if (rc) {
+               pr_err("Cannot register watchdog device (err=%d)\n", rc);
+               goto err_out_reboot;
+       }
+
+       pr_info("Chip IT%04x revision %d initialized. timeout=%d sec (nowayout=%d testmode=%d nogameport=%d nocir=%d)\n",
                chip_type, chip_rev, timeout,
-               nowayout, testmode, exclusive, nogameport, nocir);
+               nowayout, testmode, nogameport, nocir);
 
        superio_exit();
        return 0;
@@ -778,7 +545,7 @@ static void __exit it87_wdt_exit(void)
                superio_exit();
        }
 
-       misc_deregister(&wdt_miscdev);
+       watchdog_unregister_device(&wdt_dev);
        unregister_reboot_notifier(&wdt_notifier);
 
        if (test_bit(WDTS_USE_GP, &wdt_status))