watchdog: bcm47xx_wdt.c: use platform device

Instead of accessing the function to set the watchdog timer directly,
register a platform driver the platform could register to use this
watchdog driver.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

2 files changed, 87 insertions, 78 deletions

diff --git a/drivers/watchdog/bcm47xx_wdt.c b/drivers/watchdog/bcm47xx_wdt.c
index 4c520d68397e..97ccfce0dabb 100644
--- a/drivers/watchdog/bcm47xx_wdt.c
+++ b/drivers/watchdog/bcm47xx_wdt.c
@@ -3,6 +3,7 @@
  *
  *  Copyright (C) 2008 Aleksandar Radovanovic <biblbroks@sezampro.rs>
  *  Copyright (C) 2009 Matthieu CASTET <castet.matthieu@free.fr>
+ *  Copyright (C) 2012-2013 Hauke Mehrtens <hauke@hauke-m.de>
  *
  *  This program is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License
@@ -12,19 +13,19 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/bcm47xx_wdt.h>
 #include <linux/bitops.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/platform_device.h>
 #include <linux/reboot.h>
 #include <linux/types.h>
 #include <linux/watchdog.h>
 #include <linux/timer.h>
 #include <linux/jiffies.h>
-#include <linux/ssb/ssb_embedded.h>
-#include <asm/mach-bcm47xx/bcm47xx.h>
 
 #define DRV_NAME                "bcm47xx_wdt"
 
@@ -43,48 +44,19 @@ MODULE_PARM_DESC(nowayout,
                 "Watchdog cannot be stopped once started (default="
                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
-static struct timer_list wdt_timer;
-static atomic_t ticks;
-
-static inline void bcm47xx_wdt_hw_start(void)
+static inline struct bcm47xx_wdt *bcm47xx_wdt_get(struct watchdog_device *wdd)
 {
-        /* this is 2,5s on 100Mhz clock  and 2s on 133 Mhz */
-        switch (bcm47xx_bus_type) {
-#ifdef CONFIG_BCM47XX_SSB
-        case BCM47XX_BUS_TYPE_SSB:
-                ssb_watchdog_timer_set(&bcm47xx_bus.ssb, 0xfffffff);
-                break;
-#endif
-#ifdef CONFIG_BCM47XX_BCMA
-        case BCM47XX_BUS_TYPE_BCMA:
-                bcma_chipco_watchdog_timer_set(&bcm47xx_bus.bcma.bus.drv_cc,
-                                               0xfffffff);
-                break;
-#endif
-        }
+        return container_of(wdd, struct bcm47xx_wdt, wdd);
 }
 
-static inline int bcm47xx_wdt_hw_stop(void)
+static void bcm47xx_timer_tick(unsigned long data)
 {
-        switch (bcm47xx_bus_type) {
-#ifdef CONFIG_BCM47XX_SSB
-        case BCM47XX_BUS_TYPE_SSB:
-                return ssb_watchdog_timer_set(&bcm47xx_bus.ssb, 0);
-#endif
-#ifdef CONFIG_BCM47XX_BCMA
-        case BCM47XX_BUS_TYPE_BCMA:
-                bcma_chipco_watchdog_timer_set(&bcm47xx_bus.bcma.bus.drv_cc, 0);
-                return 0;
-#endif
-        }
-        return -EINVAL;
-}
+        struct bcm47xx_wdt *wdt = (struct bcm47xx_wdt *)data;
+        u32 next_tick = min(wdt->wdd.timeout * 1000, wdt->max_timer_ms);
 
-static void bcm47xx_timer_tick(unsigned long unused)
-{
-        if (!atomic_dec_and_test(&ticks)) {
-                bcm47xx_wdt_hw_start();
-                mod_timer(&wdt_timer, jiffies + HZ);
+        if (!atomic_dec_and_test(&wdt->soft_ticks)) {
+                wdt->timer_set_ms(wdt, next_tick);
+                mod_timer(&wdt->soft_timer, jiffies + HZ);
         } else {
                 pr_crit("Watchdog will fire soon!!!\n");
         }
@@ -92,23 +64,29 @@ static void bcm47xx_timer_tick(unsigned long unused)
 
 static int bcm47xx_wdt_keepalive(struct watchdog_device *wdd)
 {
-        atomic_set(&ticks, wdt_time);
+        struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+        atomic_set(&wdt->soft_ticks, wdd->timeout);
 
         return 0;
 }
 
 static int bcm47xx_wdt_start(struct watchdog_device *wdd)
 {
-        bcm47xx_wdt_pet();
-        bcm47xx_timer_tick(0);
+        struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+        bcm47xx_wdt_keepalive(wdd);
+        bcm47xx_timer_tick((unsigned long)wdt);
 
         return 0;
 }
 
 static int bcm47xx_wdt_stop(struct watchdog_device *wdd)
 {
-        del_timer_sync(&wdt_timer);
-        bcm47xx_wdt_hw_stop();
+        struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+        del_timer_sync(&wdt->soft_timer);
+        wdt->timer_set(wdt, 0);
 
         return 0;
 }
@@ -116,10 +94,13 @@ static int bcm47xx_wdt_stop(struct watchdog_device *wdd)
 static int bcm47xx_wdt_set_timeout(struct watchdog_device *wdd,
                                    unsigned int new_time)
 {
-        if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
+        if (new_time < 1 || new_time > WDT_MAX_TIME) {
+                pr_warn("timeout value must be 1<=x<=%d, using %d\n",
+                        WDT_MAX_TIME, new_time);
                 return -EINVAL;
+        }
 
-        wdt_time = new_time;
+        wdd->timeout = new_time;
         return 0;
 }
 
@@ -133,8 +114,11 @@ static const struct watchdog_info bcm47xx_wdt_info = {
 static int bcm47xx_wdt_notify_sys(struct notifier_block *this,
                                   unsigned long code, void *unused)
 {
+        struct bcm47xx_wdt *wdt;
+
+        wdt = container_of(this, struct bcm47xx_wdt, notifier);
         if (code == SYS_DOWN || code == SYS_HALT)
-                bcm47xx_wdt_stop();
+                wdt->wdd.ops->stop(&wdt->wdd);
         return NOTIFY_DONE;
 }
 
@@ -146,56 +130,72 @@ static struct watchdog_ops bcm47xx_wdt_ops = {
         .set_timeout    = bcm47xx_wdt_set_timeout,
 };
 
-static struct watchdog_device bcm47xx_wdt_wdd = {
-        .info           = &bcm47xx_wdt_info,
-        .ops            = &bcm47xx_wdt_ops,
-};
-
-static struct notifier_block bcm47xx_wdt_notifier = {
-        .notifier_call = bcm47xx_wdt_notify_sys,
-};
-
-static int __init bcm47xx_wdt_init(void)
+static int bcm47xx_wdt_probe(struct platform_device *pdev)
 {
         int ret;
+        struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);
 
-        if (bcm47xx_wdt_hw_stop() < 0)
-                return -ENODEV;
+        if (!wdt)
+                return -ENXIO;
 
-        setup_timer(&wdt_timer, bcm47xx_timer_tick, 0L);
+        setup_timer(&wdt->soft_timer, bcm47xx_timer_tick,
+                    (long unsigned int)wdt);
 
-        if (bcm47xx_wdt_settimeout(wdt_time)) {
-                bcm47xx_wdt_settimeout(WDT_DEFAULT_TIME);
-                pr_info("wdt_time value must be 0 < wdt_time < %d, using %d\n",
-                        (WDT_MAX_TIME + 1), wdt_time);
-        }
-        watchdog_set_nowayout(&bcm47xx_wdt_wdd, nowayout);
+        wdt->wdd.ops = &bcm47xx_wdt_ops;
+        wdt->wdd.info = &bcm47xx_wdt_info;
+        wdt->wdd.timeout = WDT_DEFAULT_TIME;
+        ret = wdt->wdd.ops->set_timeout(&wdt->wdd, timeout);
+        if (ret)
+                goto err_timer;
+        watchdog_set_nowayout(&wdt->wdd, nowayout);
+
+        wdt->notifier.notifier_call = &bcm47xx_wdt_notify_sys;
 
-        ret = register_reboot_notifier(&bcm47xx_wdt_notifier);
+        ret = register_reboot_notifier(&wdt->notifier);
         if (ret)
-                return ret;
+                goto err_timer;
 
-        ret = watchdog_register_device(&bcm47xx_wdt_wdd);
-        if (ret) {
-                unregister_reboot_notifier(&bcm47xx_wdt_notifier);
-                return ret;
-        }
+        ret = watchdog_register_device(&wdt->wdd);
+        if (ret)
+                goto err_notifier;
 
         pr_info("BCM47xx Watchdog Timer enabled (%d seconds%s)\n",
                 wdt_time, nowayout ? ", nowayout" : "");
         return 0;
+
+err_notifier:
+        unregister_reboot_notifier(&wdt->notifier);
+err_timer:
+        del_timer_sync(&wdt->soft_timer);
+
+        return ret;
 }
 
-static void __exit bcm47xx_wdt_exit(void)
+static int bcm47xx_wdt_remove(struct platform_device *pdev)
 {
-        watchdog_unregister_device(&bcm47xx_wdt_wdd);
+        struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);
+
+        if (!wdt)
+                return -ENXIO;
+
+        watchdog_unregister_device(&wdt->wdd);
+        unregister_reboot_notifier(&wdt->notifier);
 
-        unregister_reboot_notifier(&bcm47xx_wdt_notifier);
+        return 0;
 }
 
-module_init(bcm47xx_wdt_init);
-module_exit(bcm47xx_wdt_exit);
+static struct platform_driver bcm47xx_wdt_driver = {
+        .driver         = {
+                .owner  = THIS_MODULE,
+                .name   = "bcm47xx-wdt",
+        },
+        .probe          = bcm47xx_wdt_probe,
+        .remove         = bcm47xx_wdt_remove,
+};
+
+module_platform_driver(bcm47xx_wdt_driver);
 
 MODULE_AUTHOR("Aleksandar Radovanovic");
+MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
 MODULE_DESCRIPTION("Watchdog driver for Broadcom BCM47xx");
 MODULE_LICENSE("GPL");
diff --git a/include/linux/bcm47xx_wdt.h b/include/linux/bcm47xx_wdt.h
index e5dfc256485b..b708786d4cbf 100644
--- a/include/linux/bcm47xx_wdt.h
+++ b/include/linux/bcm47xx_wdt.h
@@ -1,7 +1,10 @@
 #ifndef LINUX_BCM47XX_WDT_H_
 #define LINUX_BCM47XX_WDT_H_
 
+#include <linux/notifier.h>
+#include <linux/timer.h>
 #include <linux/types.h>
+#include <linux/watchdog.h>
 
 
 struct bcm47xx_wdt {
@@ -10,6 +13,12 @@ struct bcm47xx_wdt {
         u32 max_timer_ms;
 
         void *driver_data;
+
+        struct watchdog_device wdd;
+        struct notifier_block notifier;
+
+        struct timer_list soft_timer;
+        atomic_t soft_ticks;
 };
 
 static inline void *bcm47xx_wdt_get_drvdata(struct bcm47xx_wdt *wdt)