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/w83627hf_wdt.c b/drivers/watchdog/w83627hf_wdt.c
new file mode 100644
index 0000000..5824e25
--- /dev/null
+++ b/drivers/watchdog/w83627hf_wdt.c
@@ -0,0 +1,497 @@
+/*
+ *	w83627hf/thf WDT driver
+ *
+ *	(c) Copyright 2013 Guenter Roeck
+ *		converted to watchdog infrastructure
+ *
+ *	(c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
+ *		added support for W83627THF.
+ *
+ *	(c) Copyright 2003,2007 Pádraig Brady <P@draigBrady.com>
+ *
+ *	Based on advantechwdt.c which is based on wdt.c.
+ *	Original copyright messages:
+ *
+ *	(c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
+ *
+ *	(c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
+ *						All Rights Reserved.
+ *
+ *	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.
+ *
+ *	Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
+ *	warranty for any of this software. This material is provided
+ *	"AS-IS" and at no charge.
+ *
+ *	(c) Copyright 1995    Alan Cox <alan@lxorguk.ukuu.org.uk>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <linux/ioport.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/io.h>
+
+#define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT"
+#define WATCHDOG_TIMEOUT 60		/* 60 sec default timeout */
+
+static int wdt_io;
+static int cr_wdt_timeout;	/* WDT timeout register */
+static int cr_wdt_control;	/* WDT control register */
+
+enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
+	     w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg, w83627dhg_p,
+	     w83667hg_b, nct6775, nct6776, nct6779, nct6791, nct6792 };
+
+static int timeout;			/* in seconds */
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout,
+		"Watchdog timeout in seconds. 1 <= timeout <= 255, default="
+				__MODULE_STRING(WATCHDOG_TIMEOUT) ".");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout,
+		"Watchdog cannot be stopped once started (default="
+				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static int early_disable;
+module_param(early_disable, int, 0);
+MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
+
+/*
+ *	Kernel methods.
+ */
+
+#define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
+#define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
+							(same as EFER) */
+#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
+
+#define W83627HF_LD_WDT		0x08
+
+#define W83627HF_ID		0x52
+#define W83627S_ID		0x59
+#define W83697HF_ID		0x60
+#define W83697UG_ID		0x68
+#define W83637HF_ID		0x70
+#define W83627THF_ID		0x82
+#define W83687THF_ID		0x85
+#define W83627EHF_ID		0x88
+#define W83627DHG_ID		0xa0
+#define W83627UHG_ID		0xa2
+#define W83667HG_ID		0xa5
+#define W83627DHG_P_ID		0xb0
+#define W83667HG_B_ID		0xb3
+#define NCT6775_ID		0xb4
+#define NCT6776_ID		0xc3
+#define NCT6779_ID		0xc5
+#define NCT6791_ID		0xc8
+#define NCT6792_ID		0xc9
+
+#define W83627HF_WDT_TIMEOUT	0xf6
+#define W83697HF_WDT_TIMEOUT	0xf4
+
+#define W83627HF_WDT_CONTROL	0xf5
+#define W83697HF_WDT_CONTROL	0xf3
+
+static void superio_outb(int reg, int val)
+{
+	outb(reg, WDT_EFER);
+	outb(val, WDT_EFDR);
+}
+
+static inline int superio_inb(int reg)
+{
+	outb(reg, WDT_EFER);
+	return inb(WDT_EFDR);
+}
+
+static int superio_enter(void)
+{
+	if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
+		return -EBUSY;
+
+	outb_p(0x87, WDT_EFER); /* Enter extended function mode */
+	outb_p(0x87, WDT_EFER); /* Again according to manual */
+
+	return 0;
+}
+
+static void superio_select(int ld)
+{
+	superio_outb(0x07, ld);
+}
+
+static void superio_exit(void)
+{
+	outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
+	release_region(wdt_io, 2);
+}
+
+static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
+{
+	int ret;
+	unsigned char t;
+
+	ret = superio_enter();
+	if (ret)
+		return ret;
+
+	superio_select(W83627HF_LD_WDT);
+
+	/* set CR30 bit 0 to activate GPIO2 */
+	t = superio_inb(0x30);
+	if (!(t & 0x01))
+		superio_outb(0x30, t | 0x01);
+
+	switch (chip) {
+	case w83627hf:
+	case w83627s:
+		t = superio_inb(0x2B) & ~0x10;
+		superio_outb(0x2B, t); /* set GPIO24 to WDT0 */
+		break;
+	case w83697hf:
+		/* Set pin 119 to WDTO# mode (= CR29, WDT0) */
+		t = superio_inb(0x29) & ~0x60;
+		t |= 0x20;
+		superio_outb(0x29, t);
+		break;
+	case w83697ug:
+		/* Set pin 118 to WDTO# mode */
+		t = superio_inb(0x2b) & ~0x04;
+		superio_outb(0x2b, t);
+		break;
+	case w83627thf:
+		t = (superio_inb(0x2B) & ~0x08) | 0x04;
+		superio_outb(0x2B, t); /* set GPIO3 to WDT0 */
+		break;
+	case w83627dhg:
+	case w83627dhg_p:
+		t = superio_inb(0x2D) & ~0x01; /* PIN77 -> WDT0# */
+		superio_outb(0x2D, t); /* set GPIO5 to WDT0 */
+		t = superio_inb(cr_wdt_control);
+		t |= 0x02;	/* enable the WDTO# output low pulse
+				 * to the KBRST# pin */
+		superio_outb(cr_wdt_control, t);
+		break;
+	case w83637hf:
+		break;
+	case w83687thf:
+		t = superio_inb(0x2C) & ~0x80; /* PIN47 -> WDT0# */
+		superio_outb(0x2C, t);
+		break;
+	case w83627ehf:
+	case w83627uhg:
+	case w83667hg:
+	case w83667hg_b:
+	case nct6775:
+	case nct6776:
+	case nct6779:
+	case nct6791:
+	case nct6792:
+		/*
+		 * These chips have a fixed WDTO# output pin (W83627UHG),
+		 * or support more than one WDTO# output pin.
+		 * Don't touch its configuration, and hope the BIOS
+		 * does the right thing.
+		 */
+		t = superio_inb(cr_wdt_control);
+		t |= 0x02;	/* enable the WDTO# output low pulse
+				 * to the KBRST# pin */
+		superio_outb(cr_wdt_control, t);
+		break;
+	default:
+		break;
+	}
+
+	t = superio_inb(cr_wdt_timeout);
+	if (t != 0) {
+		if (early_disable) {
+			pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
+			superio_outb(cr_wdt_timeout, 0);
+		} else {
+			pr_info("Watchdog already running. Resetting timeout to %d sec\n",
+				wdog->timeout);
+			superio_outb(cr_wdt_timeout, wdog->timeout);
+		}
+	}
+
+	/* set second mode & disable keyboard turning off watchdog */
+	t = superio_inb(cr_wdt_control) & ~0x0C;
+	superio_outb(cr_wdt_control, t);
+
+	/* reset trigger, disable keyboard & mouse turning off watchdog */
+	t = superio_inb(0xF7) & ~0xD0;
+	superio_outb(0xF7, t);
+
+	superio_exit();
+
+	return 0;
+}
+
+static int wdt_set_time(unsigned int timeout)
+{
+	int ret;
+
+	ret = superio_enter();
+	if (ret)
+		return ret;
+
+	superio_select(W83627HF_LD_WDT);
+	superio_outb(cr_wdt_timeout, timeout);
+	superio_exit();
+
+	return 0;
+}
+
+static int wdt_start(struct watchdog_device *wdog)
+{
+	return wdt_set_time(wdog->timeout);
+}
+
+static int wdt_stop(struct watchdog_device *wdog)
+{
+	return wdt_set_time(0);
+}
+
+static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
+{
+	wdog->timeout = timeout;
+
+	return 0;
+}
+
+static unsigned int wdt_get_time(struct watchdog_device *wdog)
+{
+	unsigned int timeleft;
+	int ret;
+
+	ret = superio_enter();
+	if (ret)
+		return 0;
+
+	superio_select(W83627HF_LD_WDT);
+	timeleft = superio_inb(cr_wdt_timeout);
+	superio_exit();
+
+	return timeleft;
+}
+
+/*
+ *	Notifier for system down
+ */
+static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
+	void *unused)
+{
+	if (code == SYS_DOWN || code == SYS_HALT)
+		wdt_set_time(0);	/* Turn the WDT off */
+
+	return NOTIFY_DONE;
+}
+
+/*
+ *	Kernel Interfaces
+ */
+
+static struct watchdog_info wdt_info = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+	.identity = "W83627HF Watchdog",
+};
+
+static struct watchdog_ops wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = wdt_start,
+	.stop = wdt_stop,
+	.set_timeout = wdt_set_timeout,
+	.get_timeleft = wdt_get_time,
+};
+
+static struct watchdog_device wdt_dev = {
+	.info = &wdt_info,
+	.ops = &wdt_ops,
+	.timeout = WATCHDOG_TIMEOUT,
+	.min_timeout = 1,
+	.max_timeout = 255,
+};
+
+/*
+ *	The WDT needs to learn about soft shutdowns in order to
+ *	turn the timebomb registers off.
+ */
+
+static struct notifier_block wdt_notifier = {
+	.notifier_call = wdt_notify_sys,
+};
+
+static int wdt_find(int addr)
+{
+	u8 val;
+	int ret;
+
+	cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
+	cr_wdt_control = W83627HF_WDT_CONTROL;
+
+	ret = superio_enter();
+	if (ret)
+		return ret;
+	superio_select(W83627HF_LD_WDT);
+	val = superio_inb(0x20);
+	switch (val) {
+	case W83627HF_ID:
+		ret = w83627hf;
+		break;
+	case W83627S_ID:
+		ret = w83627s;
+		break;
+	case W83697HF_ID:
+		ret = w83697hf;
+		cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
+		cr_wdt_control = W83697HF_WDT_CONTROL;
+		break;
+	case W83697UG_ID:
+		ret = w83697ug;
+		cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
+		cr_wdt_control = W83697HF_WDT_CONTROL;
+		break;
+	case W83637HF_ID:
+		ret = w83637hf;
+		break;
+	case W83627THF_ID:
+		ret = w83627thf;
+		break;
+	case W83687THF_ID:
+		ret = w83687thf;
+		break;
+	case W83627EHF_ID:
+		ret = w83627ehf;
+		break;
+	case W83627DHG_ID:
+		ret = w83627dhg;
+		break;
+	case W83627DHG_P_ID:
+		ret = w83627dhg_p;
+		break;
+	case W83627UHG_ID:
+		ret = w83627uhg;
+		break;
+	case W83667HG_ID:
+		ret = w83667hg;
+		break;
+	case W83667HG_B_ID:
+		ret = w83667hg_b;
+		break;
+	case NCT6775_ID:
+		ret = nct6775;
+		break;
+	case NCT6776_ID:
+		ret = nct6776;
+		break;
+	case NCT6779_ID:
+		ret = nct6779;
+		break;
+	case NCT6791_ID:
+		ret = nct6791;
+		break;
+	case NCT6792_ID:
+		ret = nct6792;
+		break;
+	case 0xff:
+		ret = -ENODEV;
+		break;
+	default:
+		ret = -ENODEV;
+		pr_err("Unsupported chip ID: 0x%02x\n", val);
+		break;
+	}
+	superio_exit();
+	return ret;
+}
+
+static int __init wdt_init(void)
+{
+	int ret;
+	int chip;
+	const char * const chip_name[] = {
+		"W83627HF",
+		"W83627S",
+		"W83697HF",
+		"W83697UG",
+		"W83637HF",
+		"W83627THF",
+		"W83687THF",
+		"W83627EHF",
+		"W83627DHG",
+		"W83627UHG",
+		"W83667HG",
+		"W83667DHG-P",
+		"W83667HG-B",
+		"NCT6775",
+		"NCT6776",
+		"NCT6779",
+		"NCT6791",
+		"NCT6792",
+	};
+
+	wdt_io = 0x2e;
+	chip = wdt_find(0x2e);
+	if (chip < 0) {
+		wdt_io = 0x4e;
+		chip = wdt_find(0x4e);
+		if (chip < 0)
+			return chip;
+	}
+
+	pr_info("WDT driver for %s Super I/O chip initialising\n",
+		chip_name[chip]);
+
+	watchdog_init_timeout(&wdt_dev, timeout, NULL);
+	watchdog_set_nowayout(&wdt_dev, nowayout);
+
+	ret = w83627hf_init(&wdt_dev, chip);
+	if (ret) {
+		pr_err("failed to initialize watchdog (err=%d)\n", ret);
+		return ret;
+	}
+
+	ret = register_reboot_notifier(&wdt_notifier);
+	if (ret != 0) {
+		pr_err("cannot register reboot notifier (err=%d)\n", ret);
+		return ret;
+	}
+
+	ret = watchdog_register_device(&wdt_dev);
+	if (ret)
+		goto unreg_reboot;
+
+	pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
+		wdt_dev.timeout, nowayout);
+
+	return ret;
+
+unreg_reboot:
+	unregister_reboot_notifier(&wdt_notifier);
+	return ret;
+}
+
+static void __exit wdt_exit(void)
+{
+	watchdog_unregister_device(&wdt_dev);
+	unregister_reboot_notifier(&wdt_notifier);
+}
+
+module_init(wdt_init);
+module_exit(wdt_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Pádraig  Brady <P@draigBrady.com>");
+MODULE_DESCRIPTION("w83627hf/thf WDT driver");