[WATCHDOG] add SBC-FITPC2 watchdog driver (3a5f9000) · Commits · git / linux-net

drivers/watchdog/Kconfig

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		@@ -369,6 +369,28 @@ config SC520_WDT
		You can compile this driver directly into the kernel, or use
		it as a module. The module will be called sc520_wdt.

		config SBC_FITPC2_WATCHDOG
		tristate "Compulab SBC-FITPC2 watchdog"
		depends on X86
		---help---
		This is the driver for the built-in watchdog timer on the fit-PC2
		Single-board computer made by Compulab.

		It`s possible to enable watchdog timer either from BIOS (F2) or from booted Linux.
		When "Watchdog Timer Value" enabled one can set 31-255 s operational range.

		Entering BIOS setup temporary disables watchdog operation regardless to current state,
		so system will not be restarted while user in BIOS setup.

		Once watchdog was enabled the system will be restarted every
		"Watchdog Timer Value" period, so to prevent it user can restart or
		disable the watchdog.

		To compile this driver as a module, choose M here: the
		module will be called sbc_fitpc2_wdt.

		Most people will say N.

		config EUROTECH_WDT
		tristate "Eurotech CPU-1220/1410 Watchdog Timer"
		depends on X86

drivers/watchdog/Makefile

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Original line number	Diff line number	Diff line
		@@ -64,6 +64,7 @@ obj-$(CONFIG_ALIM1535_WDT) += alim1535_wdt.o
		obj-$(CONFIG_ALIM7101_WDT) += alim7101_wdt.o
		obj-$(CONFIG_GEODE_WDT) += geodewdt.o
		obj-$(CONFIG_SC520_WDT) += sc520_wdt.o
		obj-$(CONFIG_SBC_FITPC2_WATCHDOG) += sbc_fitpc2_wdt.o
		obj-$(CONFIG_EUROTECH_WDT) += eurotechwdt.o
		obj-$(CONFIG_IB700_WDT) += ib700wdt.o
		obj-$(CONFIG_IBMASR) += ibmasr.o

drivers/watchdog/sbc_fitpc2_wdt.c

0 → 100644

+267 −0

Original line number	Diff line number	Diff line
		/*
		* Watchdog driver for SBC-FITPC2 board
		*
		* Author: Denis Turischev <denis@compulab.co.il>
		*
		* Adapted from the IXP2000 watchdog driver by Deepak Saxena.
		*
		* This file is licensed under the terms of the GNU General Public
		* License version 2. This program is licensed "as is" without any
		* warranty of any kind, whether express or implied.
		*/

		#define pr_fmt(fmt) KBUILD_MODNAME " WATCHDOG: " fmt

		#include <linux/module.h>
		#include <linux/types.h>
		#include <linux/miscdevice.h>
		#include <linux/watchdog.h>
		#include <linux/ioport.h>
		#include <linux/delay.h>
		#include <linux/fs.h>
		#include <linux/init.h>
		#include <linux/moduleparam.h>
		#include <linux/dmi.h>
		#include <linux/io.h>
		#include <linux/uaccess.h>

		#include <asm/system.h>

		static int nowayout = WATCHDOG_NOWAYOUT;
		static unsigned int margin = 60; /* (secs) Default is 1 minute */
		static unsigned long wdt_status;
		static DEFINE_SPINLOCK(wdt_lock);

		#define WDT_IN_USE 0
		#define WDT_OK_TO_CLOSE 1

		#define COMMAND_PORT 0x4c
		#define DATA_PORT 0x48

		#define IFACE_ON_COMMAND 1
		#define REBOOT_COMMAND 2

		#define WATCHDOG_NAME "SBC-FITPC2 Watchdog"

		static void wdt_send_data(unsigned char command, unsigned char data)
		{
		outb(command, COMMAND_PORT);
		mdelay(100);
		outb(data, DATA_PORT);
		mdelay(200);
		}

		static void wdt_enable(void)
		{
		spin_lock(&wdt_lock);
		wdt_send_data(IFACE_ON_COMMAND, 1);
		wdt_send_data(REBOOT_COMMAND, margin);
		spin_unlock(&wdt_lock);
		}

		static void wdt_disable(void)
		{
		spin_lock(&wdt_lock);
		wdt_send_data(IFACE_ON_COMMAND, 0);
		wdt_send_data(REBOOT_COMMAND, 0);
		spin_unlock(&wdt_lock);
		}

		static int fitpc2_wdt_open(struct inode inode, struct file file)
		{
		if (test_and_set_bit(WDT_IN_USE, &wdt_status))
		return -EBUSY;

		clear_bit(WDT_OK_TO_CLOSE, &wdt_status);

		wdt_enable();

		return nonseekable_open(inode, file);
		}

		static ssize_t fitpc2_wdt_write(struct file file, const char data,
		size_t len, loff_t *ppos)
		{
		size_t i;

		if (!len)
		return 0;

		if (nowayout) {
		len = 0;
		goto out;
		}

		clear_bit(WDT_OK_TO_CLOSE, &wdt_status);

		for (i = 0; i != len; i++) {
		char c;

		if (get_user(c, data + i))
		return -EFAULT;

		if (c == 'V')
		set_bit(WDT_OK_TO_CLOSE, &wdt_status);
		}

		out:
		wdt_enable();

		return len;
		}


		static struct watchdog_info ident = {
		.options = WDIOF_MAGICCLOSE \| WDIOF_SETTIMEOUT \|
		WDIOF_KEEPALIVEPING,
		.identity = WATCHDOG_NAME,
		};


		static long fitpc2_wdt_ioctl(struct file *file, unsigned int cmd,
		unsigned long arg)
		{
		int ret = -ENOTTY;
		int time;

		switch (cmd) {
		case WDIOC_GETSUPPORT:
		ret = copy_to_user((struct watchdog_info *)arg, &ident,
		sizeof(ident)) ? -EFAULT : 0;
		break;

		case WDIOC_GETSTATUS:
		ret = put_user(0, (int *)arg);
		break;

		case WDIOC_GETBOOTSTATUS:
		ret = put_user(0, (int *)arg);
		break;

		case WDIOC_KEEPALIVE:
		wdt_enable();
		ret = 0;
		break;

		case WDIOC_SETTIMEOUT:
		ret = get_user(time, (int *)arg);
		if (ret)
		break;

		if (time < 31 \|\| time > 255) {
		ret = -EINVAL;
		break;
		}

		margin = time;
		wdt_enable();
		/* Fall through */

		case WDIOC_GETTIMEOUT:
		ret = put_user(margin, (int *)arg);
		break;
		}

		return ret;
		}

		static int fitpc2_wdt_release(struct inode inode, struct file file)
		{
		if (test_bit(WDT_OK_TO_CLOSE, &wdt_status)) {
		wdt_disable();
		pr_info("Device disabled\n");
		} else {
		pr_warning("Device closed unexpectedly -"
		" timer will not stop\n");
		wdt_enable();
		}

		clear_bit(WDT_IN_USE, &wdt_status);
		clear_bit(WDT_OK_TO_CLOSE, &wdt_status);

		return 0;
		}


		static const struct file_operations fitpc2_wdt_fops = {
		.owner = THIS_MODULE,
		.llseek = no_llseek,
		.write = fitpc2_wdt_write,
		.unlocked_ioctl = fitpc2_wdt_ioctl,
		.open = fitpc2_wdt_open,
		.release = fitpc2_wdt_release,
		};

		static struct miscdevice fitpc2_wdt_miscdev = {
		.minor = WATCHDOG_MINOR,
		.name = "watchdog",
		.fops = &fitpc2_wdt_fops,
		};

		static int __init fitpc2_wdt_init(void)
		{
		int err;

		if (strcmp("SBC-FITPC2", dmi_get_system_info(DMI_BOARD_NAME))) {
		pr_info("board name is: %s. Should be SBC-FITPC2\n",
		dmi_get_system_info(DMI_BOARD_NAME));
		return -ENODEV;
		}

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

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

		if (margin < 31 \|\| margin > 255) {
		pr_err("margin must be in range 31 - 255"
		" seconds, you tried to set %d\n", margin);
		err = -EINVAL;
		goto err_margin;
		}

		err = misc_register(&fitpc2_wdt_miscdev);
		if (!err) {
		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
		WATCHDOG_MINOR, err);
		goto err_margin;
		}

		return 0;

		err_margin:
		release_region(DATA_PORT, 1);
		err_data_port:
		release_region(COMMAND_PORT, 1);

		return err;
		}

		static void __exit fitpc2_wdt_exit(void)
		{
		misc_deregister(&fitpc2_wdt_miscdev);
		release_region(DATA_PORT, 1);
		release_region(COMMAND_PORT, 1);
		}

		module_init(fitpc2_wdt_init);
		module_exit(fitpc2_wdt_exit);

		MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
		MODULE_DESCRIPTION("SBC-FITPC2 Watchdog");

		module_param(margin, int, 0);
		MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)");

		module_param(nowayout, int, 0);
		MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");

		MODULE_LICENSE("GPL");
		MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);