File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/watchdog/rdc321x_wdt.c b/drivers/watchdog/rdc321x_wdt.c
new file mode 100644
index 0000000..47a8f1b
--- /dev/null
+++ b/drivers/watchdog/rdc321x_wdt.c
@@ -0,0 +1,298 @@
+/*
+ * RDC321x watchdog driver
+ *
+ * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
+ *
+ * This driver is highly inspired from the cpu5_wdt driver
+ *
+ * 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/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/fs.h>
+#include <linux/ioport.h>
+#include <linux/timer.h>
+#include <linux/completion.h>
+#include <linux/jiffies.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/mfd/rdc321x.h>
+
+#define RDC_WDT_MASK	0x80000000 /* Mask */
+#define RDC_WDT_EN	0x00800000 /* Enable bit */
+#define RDC_WDT_WTI	0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
+#define RDC_WDT_RST	0x00100000 /* Reset bit */
+#define RDC_WDT_WIF	0x00040000 /* WDT IRQ Flag */
+#define RDC_WDT_IRT	0x00000100 /* IRQ Routing table */
+#define RDC_WDT_CNT	0x00000001 /* WDT count */
+
+#define RDC_CLS_TMR	0x80003844 /* Clear timer */
+
+#define RDC_WDT_INTERVAL	(HZ/10+1)
+
+static int ticks = 1000;
+
+/* some device data */
+
+static struct {
+	struct completion stop;
+	int running;
+	struct timer_list timer;
+	int queue;
+	int default_ticks;
+	unsigned long inuse;
+	spinlock_t lock;
+	struct pci_dev *sb_pdev;
+	int base_reg;
+} rdc321x_wdt_device;
+
+/* generic helper functions */
+
+static void rdc321x_wdt_trigger(unsigned long unused)
+{
+	unsigned long flags;
+	u32 val;
+
+	if (rdc321x_wdt_device.running)
+		ticks--;
+
+	/* keep watchdog alive */
+	spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
+	pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
+					rdc321x_wdt_device.base_reg, &val);
+	val |= RDC_WDT_EN;
+	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
+					rdc321x_wdt_device.base_reg, val);
+	spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
+
+	/* requeue?? */
+	if (rdc321x_wdt_device.queue && ticks)
+		mod_timer(&rdc321x_wdt_device.timer,
+				jiffies + RDC_WDT_INTERVAL);
+	else {
+		/* ticks doesn't matter anyway */
+		complete(&rdc321x_wdt_device.stop);
+	}
+
+}
+
+static void rdc321x_wdt_reset(void)
+{
+	ticks = rdc321x_wdt_device.default_ticks;
+}
+
+static void rdc321x_wdt_start(void)
+{
+	unsigned long flags;
+
+	if (!rdc321x_wdt_device.queue) {
+		rdc321x_wdt_device.queue = 1;
+
+		/* Clear the timer */
+		spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
+		pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
+				rdc321x_wdt_device.base_reg, RDC_CLS_TMR);
+
+		/* Enable watchdog and set the timeout to 81.92 us */
+		pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
+					rdc321x_wdt_device.base_reg,
+					RDC_WDT_EN | RDC_WDT_CNT);
+		spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
+
+		mod_timer(&rdc321x_wdt_device.timer,
+				jiffies + RDC_WDT_INTERVAL);
+	}
+
+	/* if process dies, counter is not decremented */
+	rdc321x_wdt_device.running++;
+}
+
+static int rdc321x_wdt_stop(void)
+{
+	if (rdc321x_wdt_device.running)
+		rdc321x_wdt_device.running = 0;
+
+	ticks = rdc321x_wdt_device.default_ticks;
+
+	return -EIO;
+}
+
+/* filesystem operations */
+static int rdc321x_wdt_open(struct inode *inode, struct file *file)
+{
+	if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
+		return -EBUSY;
+
+	return nonseekable_open(inode, file);
+}
+
+static int rdc321x_wdt_release(struct inode *inode, struct file *file)
+{
+	clear_bit(0, &rdc321x_wdt_device.inuse);
+	return 0;
+}
+
+static long rdc321x_wdt_ioctl(struct file *file, unsigned int cmd,
+				unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	u32 value;
+	static const struct watchdog_info ident = {
+		.options = WDIOF_CARDRESET,
+		.identity = "RDC321x WDT",
+	};
+	unsigned long flags;
+
+	switch (cmd) {
+	case WDIOC_KEEPALIVE:
+		rdc321x_wdt_reset();
+		break;
+	case WDIOC_GETSTATUS:
+		/* Read the value from the DATA register */
+		spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
+		pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
+					rdc321x_wdt_device.base_reg, &value);
+		spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
+		if (copy_to_user(argp, &value, sizeof(u32)))
+			return -EFAULT;
+		break;
+	case WDIOC_GETSUPPORT:
+		if (copy_to_user(argp, &ident, sizeof(ident)))
+			return -EFAULT;
+		break;
+	case WDIOC_SETOPTIONS:
+		if (copy_from_user(&value, argp, sizeof(int)))
+			return -EFAULT;
+		switch (value) {
+		case WDIOS_ENABLECARD:
+			rdc321x_wdt_start();
+			break;
+		case WDIOS_DISABLECARD:
+			return rdc321x_wdt_stop();
+		default:
+			return -EINVAL;
+		}
+		break;
+	default:
+		return -ENOTTY;
+	}
+	return 0;
+}
+
+static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf,
+				size_t count, loff_t *ppos)
+{
+	if (!count)
+		return -EIO;
+
+	rdc321x_wdt_reset();
+
+	return count;
+}
+
+static const struct file_operations rdc321x_wdt_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.unlocked_ioctl	= rdc321x_wdt_ioctl,
+	.open		= rdc321x_wdt_open,
+	.write		= rdc321x_wdt_write,
+	.release	= rdc321x_wdt_release,
+};
+
+static struct miscdevice rdc321x_wdt_misc = {
+	.minor	= WATCHDOG_MINOR,
+	.name	= "watchdog",
+	.fops	= &rdc321x_wdt_fops,
+};
+
+static int rdc321x_wdt_probe(struct platform_device *pdev)
+{
+	int err;
+	struct resource *r;
+	struct rdc321x_wdt_pdata *pdata;
+
+	pdata = dev_get_platdata(&pdev->dev);
+	if (!pdata) {
+		dev_err(&pdev->dev, "no platform data supplied\n");
+		return -ENODEV;
+	}
+
+	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "wdt-reg");
+	if (!r) {
+		dev_err(&pdev->dev, "failed to get wdt-reg resource\n");
+		return -ENODEV;
+	}
+
+	rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
+	rdc321x_wdt_device.base_reg = r->start;
+
+	err = misc_register(&rdc321x_wdt_misc);
+	if (err < 0) {
+		dev_err(&pdev->dev, "misc_register failed\n");
+		return err;
+	}
+
+	spin_lock_init(&rdc321x_wdt_device.lock);
+
+	/* Reset the watchdog */
+	pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
+				rdc321x_wdt_device.base_reg, RDC_WDT_RST);
+
+	init_completion(&rdc321x_wdt_device.stop);
+	rdc321x_wdt_device.queue = 0;
+
+	clear_bit(0, &rdc321x_wdt_device.inuse);
+
+	setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
+
+	rdc321x_wdt_device.default_ticks = ticks;
+
+	dev_info(&pdev->dev, "watchdog init success\n");
+
+	return 0;
+}
+
+static int rdc321x_wdt_remove(struct platform_device *pdev)
+{
+	if (rdc321x_wdt_device.queue) {
+		rdc321x_wdt_device.queue = 0;
+		wait_for_completion(&rdc321x_wdt_device.stop);
+	}
+
+	misc_deregister(&rdc321x_wdt_misc);
+
+	return 0;
+}
+
+static struct platform_driver rdc321x_wdt_driver = {
+	.probe = rdc321x_wdt_probe,
+	.remove = rdc321x_wdt_remove,
+	.driver = {
+		.name = "rdc321x-wdt",
+	},
+};
+
+module_platform_driver(rdc321x_wdt_driver);
+
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("RDC321x watchdog driver");
+MODULE_LICENSE("GPL");