Use the MPC5200 GPT api for the WDT which drastically simplifies this file.

Signed-off-by: Albrecht Dreß <albrecht.dr...@arcor.de>
---

 drivers/watchdog/mpc5200_wdt.c |  246 +++++++++++-----------------------------
 1 files changed, 65 insertions(+), 181 deletions(-)

diff --git a/drivers/watchdog/mpc5200_wdt.c b/drivers/watchdog/mpc5200_wdt.c
index fa9c47c..5bb553c 100644
--- a/drivers/watchdog/mpc5200_wdt.c
+++ b/drivers/watchdog/mpc5200_wdt.c
@@ -2,25 +2,16 @@
 #include <linux/module.h>
 #include <linux/miscdevice.h>
 #include <linux/watchdog.h>
-#include <linux/io.h>
-#include <linux/spinlock.h>
 #include <linux/of_platform.h>
 #include <linux/uaccess.h>
 #include <asm/mpc52xx.h>
 
 
-#define GPT_MODE_WDT           (1 << 15)
-#define GPT_MODE_CE            (1 << 12)
-#define GPT_MODE_MS_TIMER      (0x4)
-
+#define WDT_IDENTITY        "mpc5200 watchdog on GPT0"
 
 struct mpc5200_wdt {
-       unsigned count; /* timer ticks before watchdog kicks in */
-       long ipb_freq;
-       struct miscdevice miscdev;
-       struct resource mem;
-       struct mpc52xx_gpt __iomem *regs;
-       spinlock_t io_lock;
+       int timeout;
+       struct mpc52xx_gpt_priv *timer;
 };
 
 /* is_active stores wether or not the /dev/watchdog device is opened */
@@ -32,80 +23,33 @@ static unsigned long is_active;
 static struct mpc5200_wdt *wdt_global;
 
 
-/* helper to calculate timeout in timer counts */
-static void mpc5200_wdt_set_timeout(struct mpc5200_wdt *wdt, int timeout)
-{
-       /* use biggest prescaler of 64k */
-       wdt->count = (wdt->ipb_freq + 0xffff) / 0x10000 * timeout;
-
-       if (wdt->count > 0xffff)
-               wdt->count = 0xffff;
-}
-/* return timeout in seconds (calculated from timer count) */
-static int mpc5200_wdt_get_timeout(struct mpc5200_wdt *wdt)
-{
-       return wdt->count * 0x10000 / wdt->ipb_freq;
-}
-
-
-/* watchdog operations */
-static int mpc5200_wdt_start(struct mpc5200_wdt *wdt)
-{
-       spin_lock(&wdt->io_lock);
-       /* disable */
-       out_be32(&wdt->regs->mode, 0);
-       /* set timeout, with maximum prescaler */
-       out_be32(&wdt->regs->count, 0x0 | wdt->count);
-       /* enable watchdog */
-       out_be32(&wdt->regs->mode, GPT_MODE_CE | GPT_MODE_WDT |
-                                               GPT_MODE_MS_TIMER);
-       spin_unlock(&wdt->io_lock);
-
-       return 0;
-}
-static int mpc5200_wdt_ping(struct mpc5200_wdt *wdt)
-{
-       spin_lock(&wdt->io_lock);
-       /* writing A5 to OCPW resets the watchdog */
-       out_be32(&wdt->regs->mode, 0xA5000000 |
-                               (0xffffff & in_be32(&wdt->regs->mode)));
-       spin_unlock(&wdt->io_lock);
-       return 0;
-}
-static int mpc5200_wdt_stop(struct mpc5200_wdt *wdt)
-{
-       spin_lock(&wdt->io_lock);
-       /* disable */
-       out_be32(&wdt->regs->mode, 0);
-       spin_unlock(&wdt->io_lock);
-       return 0;
-}
-
-
 /* file operations */
 static ssize_t mpc5200_wdt_write(struct file *file, const char __user *data,
-               size_t len, loff_t *ppos)
+                                size_t len, loff_t *ppos)
 {
        struct mpc5200_wdt *wdt = file->private_data;
-       mpc5200_wdt_ping(wdt);
+       mpc52xx_gpt_wdt_ping(wdt->timer);
        return 0;
 }
+
 static struct watchdog_info mpc5200_wdt_info = {
        .options        = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
-       .identity       = "mpc5200 watchdog on GPT0",
+       .identity       = WDT_IDENTITY,
 };
+
 static long mpc5200_wdt_ioctl(struct file *file, unsigned int cmd,
-                                                       unsigned long arg)
+                             unsigned long arg)
 {
        struct mpc5200_wdt *wdt = file->private_data;
        int __user *data = (int __user *)arg;
        int timeout;
+       u64 real_timeout;
        int ret = 0;
 
        switch (cmd) {
        case WDIOC_GETSUPPORT:
                ret = copy_to_user(data, &mpc5200_wdt_info,
-                                               sizeof(mpc5200_wdt_info));
+                                  sizeof(mpc5200_wdt_info));
                if (ret)
                        ret = -EFAULT;
                break;
@@ -116,19 +60,23 @@ static long mpc5200_wdt_ioctl(struct file *file, unsigned 
int cmd,
                break;
 
        case WDIOC_KEEPALIVE:
-               mpc5200_wdt_ping(wdt);
+               mpc52xx_gpt_wdt_ping(wdt->timer);
                break;
 
        case WDIOC_SETTIMEOUT:
                ret = get_user(timeout, data);
                if (ret)
                        break;
-               mpc5200_wdt_set_timeout(wdt, timeout);
-               mpc5200_wdt_start(wdt);
+               ret = mpc52xx_gpt_wdt_start(wdt->timer, timeout);
+               if (ret)
+                       break;
+               wdt->timeout = timeout;
                /* fall through and return the timeout */
 
        case WDIOC_GETTIMEOUT:
-               timeout = mpc5200_wdt_get_timeout(wdt);
+               real_timeout = mpc52xx_gpt_timer_period(wdt->timer);
+               do_div(real_timeout, 1000000000);
+               timeout = (int) real_timeout;
                ret = put_user(timeout, data);
                break;
 
@@ -140,154 +88,90 @@ static long mpc5200_wdt_ioctl(struct file *file, unsigned 
int cmd,
 
 static int mpc5200_wdt_open(struct inode *inode, struct file *file)
 {
+       int ret;
+
        /* /dev/watchdog can only be opened once */
        if (test_and_set_bit(0, &is_active))
                return -EBUSY;
 
        /* Set and activate the watchdog */
-       mpc5200_wdt_set_timeout(wdt_global, 30);
-       mpc5200_wdt_start(wdt_global);
+       ret = mpc52xx_gpt_wdt_start(wdt_global->timer, 30);
+       if (ret) {
+               clear_bit(0, &is_active);
+               return ret;
+       }
+       wdt_global->timeout = 30;
+
        file->private_data = wdt_global;
        return nonseekable_open(inode, file);
 }
+
 static int mpc5200_wdt_release(struct inode *inode, struct file *file)
 {
-#if WATCHDOG_NOWAYOUT == 0
+#if !defined(CONFIG_WATCHDOG_NOWAYOUT)
        struct mpc5200_wdt *wdt = file->private_data;
-       mpc5200_wdt_stop(wdt);
-       wdt->count = 0;         /* == disabled */
+       mpc52xx_gpt_wdt_stop(wdt->timer);
+       wdt->timeout = 0;               /* == disabled */
 #endif
        clear_bit(0, &is_active);
        return 0;
 }
 
 static const struct file_operations mpc5200_wdt_fops = {
-       .owner  = THIS_MODULE,
-       .write  = mpc5200_wdt_write,
+       .owner          = THIS_MODULE,
+       .llseek         = no_llseek,
+       .write          = mpc5200_wdt_write,
        .unlocked_ioctl = mpc5200_wdt_ioctl,
-       .open   = mpc5200_wdt_open,
-       .release = mpc5200_wdt_release,
+       .open           = mpc5200_wdt_open,
+       .release        = mpc5200_wdt_release,
+};
+
+static struct miscdevice mpc5200_wdt_miscdev = {
+       .minor          = WATCHDOG_MINOR,
+       .name           = "watchdog",
+       .fops           = &mpc5200_wdt_fops,
 };
 
 /* module operations */
-static int mpc5200_wdt_probe(struct of_device *op,
-                                       const struct of_device_id *match)
+static int __init mpc5200_wdt_init(void)
 {
-       struct mpc5200_wdt *wdt;
        int err;
-       const void *has_wdt;
-       int size;
+       struct mpc52xx_gpt_priv *timer;
 
-       has_wdt = of_get_property(op->node, "has-wdt", NULL);
-       if (!has_wdt)
-               has_wdt = of_get_property(op->node, "fsl,has-wdt", NULL);
-       if (!has_wdt)
+       /* grab the watchdog-capable gpt */
+       timer = mpc52xx_gpt_wdt_probe();
+       if (!timer) {
+               pr_err(WDT_IDENTITY ": probing failed\n");
                return -ENODEV;
+       }
 
-       wdt = kzalloc(sizeof(*wdt), GFP_KERNEL);
-       if (!wdt)
+       wdt_global = kzalloc(sizeof(struct mpc5200_wdt), GFP_KERNEL);
+       if (!wdt_global) {
+               mpc52xx_gpt_wdt_release(timer);
                return -ENOMEM;
-
-       wdt->ipb_freq = mpc5xxx_get_bus_frequency(op->node);
-
-       err = of_address_to_resource(op->node, 0, &wdt->mem);
-       if (err)
-               goto out_free;
-       size = wdt->mem.end - wdt->mem.start + 1;
-       if (!request_mem_region(wdt->mem.start, size, "mpc5200_wdt")) {
-               err = -ENODEV;
-               goto out_free;
-       }
-       wdt->regs = ioremap(wdt->mem.start, size);
-       if (!wdt->regs) {
-               err = -ENODEV;
-               goto out_release;
        }
-
-       dev_set_drvdata(&op->dev, wdt);
-       spin_lock_init(&wdt->io_lock);
-
-       wdt->miscdev = (struct miscdevice) {
-               .minor  = WATCHDOG_MINOR,
-               .name   = "watchdog",
-               .fops   = &mpc5200_wdt_fops,
-               .parent = &op->dev,
-       };
-       wdt_global = wdt;
-       err = misc_register(&wdt->miscdev);
+       wdt_global->timer = timer;
+       err = misc_register(&mpc5200_wdt_miscdev);
        if (!err)
-               return 0;
-
-       iounmap(wdt->regs);
-out_release:
-       release_mem_region(wdt->mem.start, size);
-out_free:
-       kfree(wdt);
+               pr_info(WDT_IDENTITY ": registered\n");
+       else {
+               mpc52xx_gpt_wdt_release(timer);
+               kfree(wdt_global);
+       }
        return err;
 }
 
-static int mpc5200_wdt_remove(struct of_device *op)
-{
-       struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev);
-
-       mpc5200_wdt_stop(wdt);
-       misc_deregister(&wdt->miscdev);
-       iounmap(wdt->regs);
-       release_mem_region(wdt->mem.start, wdt->mem.end - wdt->mem.start + 1);
-       kfree(wdt);
-
-       return 0;
-}
-static int mpc5200_wdt_suspend(struct of_device *op, pm_message_t state)
-{
-       struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev);
-       mpc5200_wdt_stop(wdt);
-       return 0;
-}
-static int mpc5200_wdt_resume(struct of_device *op)
-{
-       struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev);
-       if (wdt->count)
-               mpc5200_wdt_start(wdt);
-       return 0;
-}
-static int mpc5200_wdt_shutdown(struct of_device *op)
-{
-       struct mpc5200_wdt *wdt = dev_get_drvdata(&op->dev);
-       mpc5200_wdt_stop(wdt);
-       return 0;
-}
-
-static struct of_device_id mpc5200_wdt_match[] = {
-       { .compatible = "mpc5200-gpt", },
-       { .compatible = "fsl,mpc5200-gpt", },
-       {},
-};
-static struct of_platform_driver mpc5200_wdt_driver = {
-       .owner          = THIS_MODULE,
-       .name           = "mpc5200-gpt-wdt",
-       .match_table    = mpc5200_wdt_match,
-       .probe          = mpc5200_wdt_probe,
-       .remove         = mpc5200_wdt_remove,
-       .suspend        = mpc5200_wdt_suspend,
-       .resume         = mpc5200_wdt_resume,
-       .shutdown       = mpc5200_wdt_shutdown,
-};
-
-
-static int __init mpc5200_wdt_init(void)
-{
-       return of_register_platform_driver(&mpc5200_wdt_driver);
-}
-
 static void __exit mpc5200_wdt_exit(void)
 {
-       of_unregister_platform_driver(&mpc5200_wdt_driver);
+       mpc52xx_gpt_wdt_release(wdt_global->timer);
+       misc_deregister(&mpc5200_wdt_miscdev);
+       kfree(wdt_global);
 }
 
 module_init(mpc5200_wdt_init);
 module_exit(mpc5200_wdt_exit);
 
-MODULE_AUTHOR("Domen Puncer <domen.pun...@telargo.com>");
+MODULE_AUTHOR("Domen Puncer <domen.pun...@telargo.com>, "
+             "Albrecht Dreß <albrecht.dr...@arcor.de>");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);

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