drivers/watchdog/w83697ug_wdt.c - kernel/msm-4.9 - Gitiles

 /*
  *	w83697ug/uf WDT driver
  *
  *	(c) Copyright 2008 Flemming Fransen <ff@nrvissing.net>
  *		reused original code to support w83697ug/uf.
  *
  *	Based on w83627hf_wdt.c which is based on advantechwdt.c
  *	which is based on wdt.c.
  *	Original copyright messages:
  *
  *	(c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
  *		added support for W83627THF.
  *
  *	(c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
  *
  *	(c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
  *
  *	(c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
  *				http://www.redhat.com
  *
  *	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@redhat.com>
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/types.h>
 #include <linux/miscdevice.h>
 #include <linux/watchdog.h>
 #include <linux/fs.h>
 #include <linux/ioport.h>
 #include <linux/notifier.h>
 #include <linux/reboot.h>
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/io.h>
 #include <linux/uaccess.h>


 #define WATCHDOG_NAME "w83697ug/uf WDT"
 #define WATCHDOG_TIMEOUT 60		/* 60 sec default timeout */

 static unsigned long wdt_is_open;
 static char expect_close;
 static DEFINE_SPINLOCK(io_lock);

 static int wdt_io = 0x2e;
 module_param(wdt_io, int, 0);
 MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)");

 static int timeout = WATCHDOG_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) ")");

 /*
  *	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 */

 static int w83697ug_select_wd_register(void)
 {
 	unsigned char c;
 	unsigned char version;

 	outb_p(0x87, WDT_EFER); /* Enter extended function mode */
 	outb_p(0x87, WDT_EFER); /* Again according to manual */

 	outb(0x20, WDT_EFER);	/* check chip version	*/
 	version = inb(WDT_EFDR);

 	if (version == 0x68) {	/* W83697UG		*/
 		pr_info("Watchdog chip version 0x%02x = W83697UG/UF found at 0x%04x\n",
 			version, wdt_io);

 		outb_p(0x2b, WDT_EFER);
 		c = inb_p(WDT_EFDR);    /* select WDT0 */
 		c &= ~0x04;
 		outb_p(0x2b, WDT_EFER);
 		outb_p(c, WDT_EFDR);	/* set pin118 to WDT0 */

 	} else {
 		pr_err("No W83697UG/UF could be found\n");
 		return -ENODEV;
 	}

 	outb_p(0x07, WDT_EFER); /* point to logical device number reg */
 	outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
 	outb_p(0x30, WDT_EFER); /* select CR30 */
 	c = inb_p(WDT_EFDR);
 	outb_p(c | 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */

 	return 0;
 }

 static void w83697ug_unselect_wd_register(void)
 {
 	outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
 }

 static int w83697ug_init(void)
 {
 	int ret;
 	unsigned char t;

 	ret = w83697ug_select_wd_register();
 	if (ret != 0)
 		return ret;

 	outb_p(0xF6, WDT_EFER); /* Select CRF6 */
 	t = inb_p(WDT_EFDR);    /* read CRF6 */
 	if (t != 0) {
 		pr_info("Watchdog already running. Resetting timeout to %d sec\n",
 			timeout);
 		outb_p(timeout, WDT_EFDR);    /* Write back to CRF6 */
 	}
 	outb_p(0xF5, WDT_EFER); /* Select CRF5 */
 	t = inb_p(WDT_EFDR);    /* read CRF5 */
 	t &= ~0x0C;             /* set second mode &
 					disable keyboard turning off watchdog */
 	outb_p(t, WDT_EFDR);    /* Write back to CRF5 */

 	w83697ug_unselect_wd_register();
 	return 0;
 }

 static void wdt_ctrl(int timeout)
 {
 	spin_lock(&io_lock);

 	if (w83697ug_select_wd_register() < 0) {
 		spin_unlock(&io_lock);
 		return;
 	}

 	outb_p(0xF4, WDT_EFER);    /* Select CRF4 */
 	outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */

 	w83697ug_unselect_wd_register();

 	spin_unlock(&io_lock);
 }

 static int wdt_ping(void)
 {
 	wdt_ctrl(timeout);
 	return 0;
 }

 static int wdt_disable(void)
 {
 	wdt_ctrl(0);
 	return 0;
 }

 static int wdt_set_heartbeat(int t)
 {
 	if (t < 1 || t > 255)
 		return -EINVAL;

 	timeout = t;
 	return 0;
 }

 static ssize_t wdt_write(struct file *file, const char __user *buf,
 						size_t count, loff_t *ppos)
 {
 	if (count) {
 		if (!nowayout) {
 			size_t i;

 			expect_close = 0;

 			for (i = 0; i != count; i++) {
 				char c;
 				if (get_user(c, buf + i))
 					return -EFAULT;
 				if (c == 'V')
 					expect_close = 42;
 			}
 		}
 		wdt_ping();
 	}
 	return count;
 }

 static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
 	int new_timeout;
 	static const struct watchdog_info ident = {
 		.options =		WDIOF_KEEPALIVEPING |
 					WDIOF_SETTIMEOUT |
 					WDIOF_MAGICCLOSE,
 		.firmware_version =	1,
 		.identity =		"W83697UG WDT",
 	};

 	switch (cmd) {
 	case WDIOC_GETSUPPORT:
 		if (copy_to_user(argp, &ident, sizeof(ident)))
 			return -EFAULT;
 		break;

 	case WDIOC_GETSTATUS:
 	case WDIOC_GETBOOTSTATUS:
 		return put_user(0, p);

 	case WDIOC_SETOPTIONS:
 	{
 		int options, retval = -EINVAL;

 		if (get_user(options, p))
 			return -EFAULT;

 		if (options & WDIOS_DISABLECARD) {
 			wdt_disable();
 			retval = 0;
 		}

 		if (options & WDIOS_ENABLECARD) {
 			wdt_ping();
 			retval = 0;
 		}

 		return retval;
 	}

 	case WDIOC_KEEPALIVE:
 		wdt_ping();
 		break;

 	case WDIOC_SETTIMEOUT:
 		if (get_user(new_timeout, p))
 			return -EFAULT;
 		if (wdt_set_heartbeat(new_timeout))
 			return -EINVAL;
 		wdt_ping();
 		/* Fall */

 	case WDIOC_GETTIMEOUT:
 		return put_user(timeout, p);

 	default:
 		return -ENOTTY;
 	}
 	return 0;
 }

 static int wdt_open(struct inode *inode, struct file *file)
 {
 	if (test_and_set_bit(0, &wdt_is_open))
 		return -EBUSY;
 	/*
 	 *	Activate
 	 */

 	wdt_ping();
 	return nonseekable_open(inode, file);
 }

 static int wdt_close(struct inode *inode, struct file *file)
 {
 	if (expect_close == 42)
 		wdt_disable();
 	else {
 		pr_crit("Unexpected close, not stopping watchdog!\n");
 		wdt_ping();
 	}
 	expect_close = 0;
 	clear_bit(0, &wdt_is_open);
 	return 0;
 }

 /*
  *	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_disable();	/* Turn the WDT off */

 	return NOTIFY_DONE;
 }

 /*
  *	Kernel Interfaces
  */

 static const struct file_operations wdt_fops = {
 	.owner		= THIS_MODULE,
 	.llseek		= no_llseek,
 	.write		= wdt_write,
 	.unlocked_ioctl	= wdt_ioctl,
 	.open		= wdt_open,
 	.release	= wdt_close,
 };

 static struct miscdevice wdt_miscdev = {
 	.minor = WATCHDOG_MINOR,
 	.name = "watchdog",
 	.fops = &wdt_fops,
 };

 /*
  *	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 __init wdt_init(void)
 {
 	int ret;

 	pr_info("WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising\n");

 	if (wdt_set_heartbeat(timeout)) {
 		wdt_set_heartbeat(WATCHDOG_TIMEOUT);
 		pr_info("timeout value must be 1<=timeout<=255, using %d\n",
 			WATCHDOG_TIMEOUT);
 	}

 	if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
 		pr_err("I/O address 0x%04x already in use\n", wdt_io);
 		ret = -EIO;
 		goto out;
 	}

 	ret = w83697ug_init();
 	if (ret != 0)
 		goto unreg_regions;

 	ret = register_reboot_notifier(&wdt_notifier);
 	if (ret != 0) {
 		pr_err("cannot register reboot notifier (err=%d)\n", ret);
 		goto unreg_regions;
 	}

 	ret = misc_register(&wdt_miscdev);
 	if (ret != 0) {
 		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
 		       WATCHDOG_MINOR, ret);
 		goto unreg_reboot;
 	}

 	pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
 		timeout, nowayout);

 out:
 	return ret;
 unreg_reboot:
 	unregister_reboot_notifier(&wdt_notifier);
 unreg_regions:
 	release_region(wdt_io, 1);
 	goto out;
 }

 static void __exit wdt_exit(void)
 {
 	misc_deregister(&wdt_miscdev);
 	unregister_reboot_notifier(&wdt_notifier);
 	release_region(wdt_io, 1);
 }

 module_init(wdt_init);
 module_exit(wdt_exit);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>");
 MODULE_DESCRIPTION("w83697ug/uf WDT driver");
	/*
	* w83697ug/uf WDT driver
	*
	* (c) Copyright 2008 Flemming Fransen <ff@nrvissing.net>
	* reused original code to support w83697ug/uf.
	*
	* Based on w83627hf_wdt.c which is based on advantechwdt.c
	* which is based on wdt.c.
	* Original copyright messages:
	*
	* (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
	* added support for W83627THF.
	*
	* (c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
	*
	* (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
	*
	* (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
	* http://www.redhat.com
	*
	* 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@redhat.com>
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/module.h>
	#include <linux/moduleparam.h>
	#include <linux/types.h>
	#include <linux/miscdevice.h>
	#include <linux/watchdog.h>
	#include <linux/fs.h>
	#include <linux/ioport.h>
	#include <linux/notifier.h>
	#include <linux/reboot.h>
	#include <linux/init.h>
	#include <linux/spinlock.h>
	#include <linux/io.h>
	#include <linux/uaccess.h>


	#define WATCHDOG_NAME "w83697ug/uf WDT"
	#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */

	static unsigned long wdt_is_open;
	static char expect_close;
	static DEFINE_SPINLOCK(io_lock);

	static int wdt_io = 0x2e;
	module_param(wdt_io, int, 0);
	MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)");

	static int timeout = WATCHDOG_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) ")");

	/*
	* 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 */

	static int w83697ug_select_wd_register(void)
	{
	unsigned char c;
	unsigned char version;

	outb_p(0x87, WDT_EFER); /* Enter extended function mode */
	outb_p(0x87, WDT_EFER); /* Again according to manual */

	outb(0x20, WDT_EFER); /* check chip version */
	version = inb(WDT_EFDR);

	if (version == 0x68) { /* W83697UG */
	pr_info("Watchdog chip version 0x%02x = W83697UG/UF found at 0x%04x\n",
	version, wdt_io);

	outb_p(0x2b, WDT_EFER);
	c = inb_p(WDT_EFDR); /* select WDT0 */
	c &= ~0x04;
	outb_p(0x2b, WDT_EFER);
	outb_p(c, WDT_EFDR); /* set pin118 to WDT0 */

	} else {
	pr_err("No W83697UG/UF could be found\n");
	return -ENODEV;
	}

	outb_p(0x07, WDT_EFER); /* point to logical device number reg */
	outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
	outb_p(0x30, WDT_EFER); /* select CR30 */
	c = inb_p(WDT_EFDR);
	outb_p(c \| 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */

	return 0;
	}

	static void w83697ug_unselect_wd_register(void)
	{
	outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
	}

	static int w83697ug_init(void)
	{
	int ret;
	unsigned char t;

	ret = w83697ug_select_wd_register();
	if (ret != 0)
	return ret;

	outb_p(0xF6, WDT_EFER); /* Select CRF6 */
	t = inb_p(WDT_EFDR); /* read CRF6 */
	if (t != 0) {
	pr_info("Watchdog already running. Resetting timeout to %d sec\n",
	timeout);
	outb_p(timeout, WDT_EFDR); /* Write back to CRF6 */
	}
	outb_p(0xF5, WDT_EFER); /* Select CRF5 */
	t = inb_p(WDT_EFDR); /* read CRF5 */
	t &= ~0x0C; /* set second mode &
	disable keyboard turning off watchdog */
	outb_p(t, WDT_EFDR); /* Write back to CRF5 */

	w83697ug_unselect_wd_register();
	return 0;
	}

	static void wdt_ctrl(int timeout)
	{
	spin_lock(&io_lock);

	if (w83697ug_select_wd_register() < 0) {
	spin_unlock(&io_lock);
	return;
	}

	outb_p(0xF4, WDT_EFER); /* Select CRF4 */
	outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */

	w83697ug_unselect_wd_register();

	spin_unlock(&io_lock);
	}

	static int wdt_ping(void)
	{
	wdt_ctrl(timeout);
	return 0;
	}

	static int wdt_disable(void)
	{
	wdt_ctrl(0);
	return 0;
	}

	static int wdt_set_heartbeat(int t)
	{
	if (t < 1 \|\| t > 255)
	return -EINVAL;

	timeout = t;
	return 0;
	}

	static ssize_t wdt_write(struct file file, const char __user buf,
	size_t count, loff_t *ppos)
	{
	if (count) {
	if (!nowayout) {
	size_t i;

	expect_close = 0;

	for (i = 0; i != count; i++) {
	char c;
	if (get_user(c, buf + i))
	return -EFAULT;
	if (c == 'V')
	expect_close = 42;
	}
	}
	wdt_ping();
	}
	return count;
	}

	static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	{
	void __user argp = (void __user )arg;
	int __user *p = argp;
	int new_timeout;
	static const struct watchdog_info ident = {
	.options = WDIOF_KEEPALIVEPING \|
	WDIOF_SETTIMEOUT \|
	WDIOF_MAGICCLOSE,
	.firmware_version = 1,
	.identity = "W83697UG WDT",
	};

	switch (cmd) {
	case WDIOC_GETSUPPORT:
	if (copy_to_user(argp, &ident, sizeof(ident)))
	return -EFAULT;
	break;

	case WDIOC_GETSTATUS:
	case WDIOC_GETBOOTSTATUS:
	return put_user(0, p);

	case WDIOC_SETOPTIONS:
	{
	int options, retval = -EINVAL;

	if (get_user(options, p))
	return -EFAULT;

	if (options & WDIOS_DISABLECARD) {
	wdt_disable();
	retval = 0;
	}

	if (options & WDIOS_ENABLECARD) {
	wdt_ping();
	retval = 0;
	}

	return retval;
	}

	case WDIOC_KEEPALIVE:
	wdt_ping();
	break;

	case WDIOC_SETTIMEOUT:
	if (get_user(new_timeout, p))
	return -EFAULT;
	if (wdt_set_heartbeat(new_timeout))
	return -EINVAL;
	wdt_ping();
	/* Fall */

	case WDIOC_GETTIMEOUT:
	return put_user(timeout, p);

	default:
	return -ENOTTY;
	}
	return 0;
	}

	static int wdt_open(struct inode inode, struct file file)
	{
	if (test_and_set_bit(0, &wdt_is_open))
	return -EBUSY;
	/*
	* Activate
	*/

	wdt_ping();
	return nonseekable_open(inode, file);
	}

	static int wdt_close(struct inode inode, struct file file)
	{
	if (expect_close == 42)
	wdt_disable();
	else {
	pr_crit("Unexpected close, not stopping watchdog!\n");
	wdt_ping();
	}
	expect_close = 0;
	clear_bit(0, &wdt_is_open);
	return 0;
	}

	/*
	* 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_disable(); /* Turn the WDT off */

	return NOTIFY_DONE;
	}

	/*
	* Kernel Interfaces
	*/

	static const struct file_operations wdt_fops = {
	.owner = THIS_MODULE,
	.llseek = no_llseek,
	.write = wdt_write,
	.unlocked_ioctl = wdt_ioctl,
	.open = wdt_open,
	.release = wdt_close,
	};

	static struct miscdevice wdt_miscdev = {
	.minor = WATCHDOG_MINOR,
	.name = "watchdog",
	.fops = &wdt_fops,
	};

	/*
	* 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 __init wdt_init(void)
	{
	int ret;

	pr_info("WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising\n");

	if (wdt_set_heartbeat(timeout)) {
	wdt_set_heartbeat(WATCHDOG_TIMEOUT);
	pr_info("timeout value must be 1<=timeout<=255, using %d\n",
	WATCHDOG_TIMEOUT);
	}

	if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
	pr_err("I/O address 0x%04x already in use\n", wdt_io);
	ret = -EIO;
	goto out;
	}

	ret = w83697ug_init();
	if (ret != 0)
	goto unreg_regions;

	ret = register_reboot_notifier(&wdt_notifier);
	if (ret != 0) {
	pr_err("cannot register reboot notifier (err=%d)\n", ret);
	goto unreg_regions;
	}

	ret = misc_register(&wdt_miscdev);
	if (ret != 0) {
	pr_err("cannot register miscdev on minor=%d (err=%d)\n",
	WATCHDOG_MINOR, ret);
	goto unreg_reboot;
	}

	pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
	timeout, nowayout);

	out:
	return ret;
	unreg_reboot:
	unregister_reboot_notifier(&wdt_notifier);
	unreg_regions:
	release_region(wdt_io, 1);
	goto out;
	}

	static void __exit wdt_exit(void)
	{
	misc_deregister(&wdt_miscdev);
	unregister_reboot_notifier(&wdt_notifier);
	release_region(wdt_io, 1);
	}

	module_init(wdt_init);
	module_exit(wdt_exit);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>");
	MODULE_DESCRIPTION("w83697ug/uf WDT driver");