watchdog: pnx4008: convert driver to use the watchdog framework

Make this driver a user of the watchdog framework and remove parts now handled
by the core. Tested on a custom lpc32xx-board.

[wim@iguana.be: Added set_timeout operation]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

1 files changed, 40 insertions, 140 deletions

diff --git a/drivers/watchdog/pnx4008_wdt.c b/drivers/watchdog/pnx4008_wdt.c
index 38fe5488cc96..3d9bb89776a7 100644
--- a/drivers/watchdog/pnx4008_wdt.c
+++ b/drivers/watchdog/pnx4008_wdt.c
@@ -8,10 +8,13 @@
  * Based on sa1100 driver,
  * Copyright (C) 2000 Oleg Drokin <green@crimea.edu>
  *
- * 2005-2006 (c) MontaVista Software, Inc. This file is licensed under
- * the terms of the GNU General Public License version 2. This program
- * is licensed "as is" without any warranty of any kind, whether express
- * or implied.
+ * 2005-2006 (c) MontaVista Software, Inc.
+ *
+ * (C) 2012 Wolfram Sang, Pengutronix
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -20,23 +23,17 @@
 #include <linux/moduleparam.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
-#include <linux/fs.h>
 #include <linux/miscdevice.h>
 #include <linux/watchdog.h>
 #include <linux/init.h>
-#include <linux/bitops.h>
-#include <linux/ioport.h>
-#include <linux/device.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/spinlock.h>
-#include <linux/uaccess.h>
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/err.h>
 #include <mach/hardware.h>
 
-#define MODULE_NAME "PNX4008-WDT: "
-
 /* WatchDog Timer - Chapter 23 Page 207 */
 
 #define DEFAULT_HEARTBEAT 19
@@ -80,19 +77,13 @@
 #define WDOG_COUNTER_RATE 13000000      /*the counter clock is 13 MHz fixed */
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
-static int heartbeat = DEFAULT_HEARTBEAT;
+static unsigned int heartbeat = DEFAULT_HEARTBEAT;
 
 static DEFINE_SPINLOCK(io_lock);
-static unsigned long wdt_status;
-#define WDT_IN_USE        0
-#define WDT_OK_TO_CLOSE   1
-
-static unsigned long boot_status;
-
 static void __iomem     *wdt_base;
 struct clk              *wdt_clk;
 
-static void wdt_enable(void)
+static int pnx4008_wdt_start(struct watchdog_device *wdd)
 {
         spin_lock(&io_lock);
 
@@ -109,144 +100,48 @@ static void wdt_enable(void)
         writel(MATCH_INT, WDTIM_INT(wdt_base));
         /* the longest pulse period 65541/(13*10^6) seconds ~ 5 ms. */
         writel(0xFFFF, WDTIM_PULSE(wdt_base));
-        writel(heartbeat * WDOG_COUNTER_RATE, WDTIM_MATCH0(wdt_base));
+        writel(wdd->timeout * WDOG_COUNTER_RATE, WDTIM_MATCH0(wdt_base));
         /*enable counter, stop when debugger active */
         writel(COUNT_ENAB | DEBUG_EN, WDTIM_CTRL(wdt_base));
 
         spin_unlock(&io_lock);
+        return 0;
 }
 
-static void wdt_disable(void)
+static int pnx4008_wdt_stop(struct watchdog_device *wdd)
 {
         spin_lock(&io_lock);
 
         writel(0, WDTIM_CTRL(wdt_base));        /*stop counter */
 
         spin_unlock(&io_lock);
+        return 0;
 }
 
-static int pnx4008_wdt_open(struct inode *inode, struct file *file)
-{
-        int ret;
-
-        if (test_and_set_bit(WDT_IN_USE, &wdt_status))
-                return -EBUSY;
-
-        clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
-        ret = clk_enable(wdt_clk);
-        if (ret) {
-                clear_bit(WDT_IN_USE, &wdt_status);
-                return ret;
-        }
-
-        wdt_enable();
-
-        return nonseekable_open(inode, file);
-}
-
-static ssize_t pnx4008_wdt_write(struct file *file, const char *data,
-                                        size_t len, loff_t *ppos)
+static int pnx4008_wdt_set_timeout(struct watchdog_device *wdd,
+                                    unsigned int new_timeout)
 {
-        if (len) {
-                if (!nowayout) {
-                        size_t i;
-
-                        clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
-                        for (i = 0; i != len; i++) {
-                                char c;
-
-                                if (get_user(c, data + i))
-                                        return -EFAULT;
-                                if (c == 'V')
-                                        set_bit(WDT_OK_TO_CLOSE, &wdt_status);
-                        }
-                }
-                wdt_enable();
-        }
-
-        return len;
+        return 0;
 }
 
-static const struct watchdog_info ident = {
+static const struct watchdog_info pnx4008_wdt_ident = {
         .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE |
             WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
         .identity = "PNX4008 Watchdog",
 };
 
-static long pnx4008_wdt_ioctl(struct file *file, unsigned int cmd,
-                                unsigned long arg)
-{
-        int ret = -ENOTTY;
-        int time;
-
-        switch (cmd) {
-        case WDIOC_GETSUPPORT:
-                ret = copy_to_user((struct watchdog_info *)arg, &ident,
-                                   sizeof(ident)) ? -EFAULT : 0;
-                break;
-
-        case WDIOC_GETSTATUS:
-                ret = put_user(0, (int *)arg);
-                break;
-
-        case WDIOC_GETBOOTSTATUS:
-                ret = put_user(boot_status, (int *)arg);
-                break;
-
-        case WDIOC_KEEPALIVE:
-                wdt_enable();
-                ret = 0;
-                break;
-
-        case WDIOC_SETTIMEOUT:
-                ret = get_user(time, (int *)arg);
-                if (ret)
-                        break;
-
-                if (time <= 0 || time > MAX_HEARTBEAT) {
-                        ret = -EINVAL;
-                        break;
-                }
-
-                heartbeat = time;
-                wdt_enable();
-                /* Fall through */
-
-        case WDIOC_GETTIMEOUT:
-                ret = put_user(heartbeat, (int *)arg);
-                break;
-        }
-        return ret;
-}
-
-static int pnx4008_wdt_release(struct inode *inode, struct file *file)
-{
-        if (!test_bit(WDT_OK_TO_CLOSE, &wdt_status))
-                pr_warn("Device closed unexpectedly\n");
-
-        wdt_disable();
-        clk_disable(wdt_clk);
-        clear_bit(WDT_IN_USE, &wdt_status);
-        clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
-        return 0;
-}
-
-static const struct file_operations pnx4008_wdt_fops = {
+static const struct watchdog_ops pnx4008_wdt_ops = {
         .owner = THIS_MODULE,
-        .llseek = no_llseek,
-        .write = pnx4008_wdt_write,
-        .unlocked_ioctl = pnx4008_wdt_ioctl,
-        .open = pnx4008_wdt_open,
-        .release = pnx4008_wdt_release,
+        .start = pnx4008_wdt_start,
+        .stop = pnx4008_wdt_stop,
+        .set_timeout = pnx4008_wdt_set_timeout,
 };
 
-static struct miscdevice pnx4008_wdt_miscdev = {
-        .minor = WATCHDOG_MINOR,
-        .name = "watchdog",
-        .fops = &pnx4008_wdt_fops,
+static struct watchdog_device pnx4008_wdd = {
+        .info = &pnx4008_wdt_ident,
+        .ops = &pnx4008_wdt_ops,
+        .min_timeout = 1,
+        .max_timeout = MAX_HEARTBEAT,
 };
 
 static int __devinit pnx4008_wdt_probe(struct platform_device *pdev)
@@ -270,15 +165,17 @@ static int __devinit pnx4008_wdt_probe(struct platform_device *pdev)
         if (ret)
                 goto out;
 
-        boot_status = (readl(WDTIM_RES(wdt_base)) & WDOG_RESET) ?
+        pnx4008_wdd.timeout = heartbeat;
+        pnx4008_wdd.bootstatus = (readl(WDTIM_RES(wdt_base)) & WDOG_RESET) ?
                         WDIOF_CARDRESET : 0;
-        wdt_disable();          /*disable for now */
-        clk_disable(wdt_clk);
+        watchdog_set_nowayout(&pnx4008_wdd, nowayout);
+
+        pnx4008_wdt_stop(&pnx4008_wdd); /* disable for now */
 
-        ret = misc_register(&pnx4008_wdt_miscdev);
+        ret = watchdog_register_device(&pnx4008_wdd);
         if (ret < 0) {
-                dev_err(&pdev->dev, "cannot register misc device\n");
-                goto out;
+                dev_err(&pdev->dev, "cannot register watchdog device\n");
+                goto disable_clk;
         }
 
         dev_info(&pdev->dev, "PNX4008 Watchdog Timer: heartbeat %d sec\n",
@@ -286,6 +183,8 @@ static int __devinit pnx4008_wdt_probe(struct platform_device *pdev)
 
         return 0;
 
+disable_clk:
+        clk_disable(wdt_clk);
 out:
         clk_put(wdt_clk);
         return ret;
@@ -293,7 +192,7 @@ out:
 
 static int __devexit pnx4008_wdt_remove(struct platform_device *pdev)
 {
-        misc_deregister(&pnx4008_wdt_miscdev);
+        watchdog_unregister_device(&pnx4008_wdd);
 
         clk_disable(wdt_clk);
         clk_put(wdt_clk);
@@ -313,9 +212,10 @@ static struct platform_driver platform_wdt_driver = {
 module_platform_driver(platform_wdt_driver);
 
 MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
+MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
 MODULE_DESCRIPTION("PNX4008 Watchdog Driver");
 
-module_param(heartbeat, int, 0);
+module_param(heartbeat, uint, 0);
 MODULE_PARM_DESC(heartbeat,
                  "Watchdog heartbeat period in seconds from 1 to "
                  __MODULE_STRING(MAX_HEARTBEAT) ", default "