[PATCH] Watchdog: Winsystems EPX-C3 SBC (eed6565f) · Commits · 戴 / test

drivers/char/watchdog/Kconfig

+22 −0

Original line number	Diff line number	Diff line
		@@ -395,6 +395,28 @@ config MACHZ_WDT
		To compile this driver as a module, choose M here: the
		module will be called machzwd.

		config SBC_EPX_C3_WATCHDOG
		tristate "Winsystems SBC EPX-C3 watchdog"
		depends on WATCHDOG && X86
		---help---
		This is the driver for the built-in watchdog timer on the EPX-C3
		Single-board computer made by Winsystems, Inc.

		Note: This hardware watchdog is not probeable and thus there
		is no way to know if writing to its IO address will corrupt
		your system or have any real effect. The only way to be sure
		that this driver does what you want is to make sure you
		are runnning it on an EPX-C3 from Winsystems with the watchdog
		timer at IO address 0x1ee and 0x1ef. It will write to both those
		IO ports. Basically, the assumption is made that if you compile
		this driver into your kernel and/or load it as a module, that you
		know what you are doing and that you are in fact running on an
		EPX-C3 board!

		To compile this driver as a module, choose M here: the
		module will be called sbc_epx_c3.


		# PowerPC Architecture

		config 8xx_WDT

drivers/char/watchdog/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -52,6 +52,7 @@ obj-$(CONFIG_W83627HF_WDT) += w83627hf_wdt.o
		obj-$(CONFIG_W83877F_WDT) += w83877f_wdt.o
		obj-$(CONFIG_W83977F_WDT) += w83977f_wdt.o
		obj-$(CONFIG_MACHZ_WDT) += machzwd.o
		obj-$(CONFIG_SBC_EPX_C3_WATCHDOG) += sbc_epx_c3.o

		# PowerPC Architecture
		obj-$(CONFIG_8xx_WDT) += mpc8xx_wdt.o

drivers/char/watchdog/sbc_epx_c3.c

0 → 100644

+216 −0

Original line number	Diff line number	Diff line
		/*
		* SBC EPX C3 0.1 A Hardware Watchdog Device for the Winsystems EPX-C3
		* single board computer
		*
		* (c) Copyright 2006 Calin A. Culianu <calin@ajvar.org>, 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.
		*
		* based on softdog.c by Alan Cox <alan@redhat.com>
		*/

		#include <linux/module.h>
		#include <linux/moduleparam.h>
		#include <linux/config.h>
		#include <linux/types.h>
		#include <linux/kernel.h>
		#include <linux/fs.h>
		#include <linux/mm.h>
		#include <linux/miscdevice.h>
		#include <linux/watchdog.h>
		#include <linux/notifier.h>
		#include <linux/reboot.h>
		#include <linux/init.h>
		#include <asm/uaccess.h>
		#include <asm/io.h>

		#define PFX "epx_c3: "
		static int epx_c3_alive;

		#define WATCHDOG_TIMEOUT 1 /* 1 sec default timeout */

		static int nowayout = WATCHDOG_NOWAYOUT;
		module_param(nowayout, int, 0);
		MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");

		#define EPXC3_WATCHDOG_CTL_REG 0x1ee /* write 1 to enable, 0 to disable */
		#define EPXC3_WATCHDOG_PET_REG 0x1ef /* write anything to pet once enabled */

		static void epx_c3_start(void)
		{
		outb(1, EPXC3_WATCHDOG_CTL_REG);
		}

		static void epx_c3_stop(void)
		{

		outb(0, EPXC3_WATCHDOG_CTL_REG);

		printk(KERN_INFO PFX "Stopped watchdog timer.\n");
		}

		static void epx_c3_pet(void)
		{
		outb(1, EPXC3_WATCHDOG_PET_REG);
		}

		/*
		* Allow only one person to hold it open
		*/
		static int epx_c3_open(struct inode inode, struct file file)
		{
		if (epx_c3_alive)
		return -EBUSY;

		if (nowayout)
		__module_get(THIS_MODULE);

		/* Activate timer */
		epx_c3_start();
		epx_c3_pet();

		epx_c3_alive = 1;
		printk(KERN_INFO "Started watchdog timer.\n");

		return nonseekable_open(inode, file);
		}

		static int epx_c3_release(struct inode inode, struct file file)
		{
		/* Shut off the timer.
		* Lock it in if it's a module and we defined ...NOWAYOUT */
		if (!nowayout)
		epx_c3_stop(); /* Turn the WDT off */

		epx_c3_alive = 0;

		return 0;
		}

		static ssize_t epx_c3_write(struct file file, const char data,
		size_t len, loff_t *ppos)
		{
		/* Refresh the timer. */
		if (len)
		epx_c3_pet();
		return len;
		}

		static int epx_c3_ioctl(struct inode inode, struct file file,
		unsigned int cmd, unsigned long arg)
		{
		int options, retval = -EINVAL;
		static struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING \|
		WDIOF_MAGICCLOSE,
		.firmware_version = 0,
		.identity = "Winsystems EPX-C3 H/W Watchdog",
		};

		switch (cmd) {
		case WDIOC_GETSUPPORT:
		if (copy_to_user((struct watchdog_info *)arg,
		&ident, sizeof(ident)))
		return -EFAULT;
		return 0;
		case WDIOC_GETSTATUS:
		case WDIOC_GETBOOTSTATUS:
		return put_user(0,(int *)arg);
		case WDIOC_KEEPALIVE:
		epx_c3_pet();
		return 0;
		case WDIOC_GETTIMEOUT:
		return put_user(WATCHDOG_TIMEOUT,(int *)arg);
		case WDIOC_SETOPTIONS: {
		if (get_user(options, (int *)arg))
		return -EFAULT;

		if (options & WDIOS_DISABLECARD) {
		epx_c3_stop();
		retval = 0;
		}

		if (options & WDIOS_ENABLECARD) {
		epx_c3_start();
		retval = 0;
		}

		return retval;
		}
		default:
		return -ENOIOCTLCMD;
		}
		}

		static int epx_c3_notify_sys(struct notifier_block *this, unsigned long code,
		void *unused)
		{
		if (code == SYS_DOWN \|\| code == SYS_HALT)
		epx_c3_stop(); /* Turn the WDT off */

		return NOTIFY_DONE;
		}

		static struct file_operations epx_c3_fops = {
		.owner = THIS_MODULE,
		.llseek = no_llseek,
		.write = epx_c3_write,
		.ioctl = epx_c3_ioctl,
		.open = epx_c3_open,
		.release = epx_c3_release,
		};

		static struct miscdevice epx_c3_miscdev = {
		.minor = WATCHDOG_MINOR,
		.name = "watchdog",
		.fops = &epx_c3_fops,
		};

		static struct notifier_block epx_c3_notifier = {
		.notifier_call = epx_c3_notify_sys,
		};

		static const char banner[] __initdata =
		KERN_INFO PFX "Hardware Watchdog Timer for Winsystems EPX-C3 SBC: 0.1\n";

		static int __init watchdog_init(void)
		{
		int ret;

		ret = register_reboot_notifier(&epx_c3_notifier);
		if (ret) {
		printk(KERN_ERR PFX "cannot register reboot notifier "
		"(err=%d)\n", ret);
		return ret;
		}

		ret = misc_register(&epx_c3_miscdev);
		if (ret) {
		printk(KERN_ERR PFX "cannot register miscdev on minor=%d "
		"(err=%d)\n", WATCHDOG_MINOR, ret);
		unregister_reboot_notifier(&epx_c3_notifier);
		return ret;
		}

		printk(banner);

		return 0;
		}

		static void __exit watchdog_exit(void)
		{
		misc_deregister(&epx_c3_miscdev);
		unregister_reboot_notifier(&epx_c3_notifier);
		}

		module_init(watchdog_init);
		module_exit(watchdog_exit);

		MODULE_AUTHOR("Calin A. Culianu <calin@ajvar.org>");
		MODULE_DESCRIPTION("Hardware Watchdog Device for Winsystems EPX-C3 SBC. Note that there is no way to probe for this device -- so only use it if you are sure you are runnning on this specific SBC system from Winsystems! It writes to IO ports 0x1ee and 0x1ef!");
		MODULE_LICENSE("GPL");
		MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);

Admin message