1 files changed, 313 insertions, 0 deletions
diff --git a/drivers/watchdog/mixcomwd.c b/drivers/watchdog/mixcomwd.c
new file mode 100644
index 000000000..d387bad37
--- /dev/null
+++ b/drivers/watchdog/mixcomwd.c
@@ -0,0 +1,313 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MixCom Watchdog: A Simple Hardware Watchdog Device
+ * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis
+ *
+ * Author: Gergely Madarasz <gorgo@itc.hu>
+ *
+ * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu>
+ *
+ * Version 0.1 (99/04/15):
+ *		- first version
+ *
+ * Version 0.2 (99/06/16):
+ *		- added kernel timer watchdog ping after close
+ *		  since the hardware does not support watchdog shutdown
+ *
+ * Version 0.3 (99/06/21):
+ *		- added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls
+ *
+ * Version 0.3.1 (99/06/22):
+ *		- allow module removal while internal timer is active,
+ *		  print warning about probable reset
+ *
+ * Version 0.4 (99/11/15):
+ *		- support for one more type board
+ *
+ * Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com>
+ *		- added nowayout module option to override
+ *		  CONFIG_WATCHDOG_NOWAYOUT
+ *
+ * Version 0.6 (2002/04/12): Rob Radez <rob@osinvestor.com>
+ *		- make mixcomwd_opened unsigned,
+ *		  removed lock_kernel/unlock_kernel from mixcomwd_release,
+ *		  modified ioctl a bit to conform to API
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#define VERSION "0.6"
+#define WATCHDOG_NAME "mixcomwd"
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/ioport.h>
+#include <linux/watchdog.h>
+#include <linux/fs.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+/*
+ * We have two types of cards that can be probed:
+ * 1) The Mixcom cards: these cards can be found at addresses
+ *    0x180, 0x280, 0x380 with an additional offset of 0xc10.
+ *    (Or 0xd90, 0xe90, 0xf90).
+ * 2) The FlashCOM cards: these cards can be set up at
+ *    0x300 -> 0x378, in 0x8 jumps with an offset of 0x04.
+ *    (Or 0x304 -> 0x37c in 0x8 jumps).
+ *    Each card has it's own ID.
+ */
+#define MIXCOM_ID 0x11
+#define FLASHCOM_ID 0x18
+static struct {
+	int ioport;
+	int id;
+} mixcomwd_io_info[] = {
+	/* The Mixcom cards */
+	{0x0d90, MIXCOM_ID},
+	{0x0e90, MIXCOM_ID},
+	{0x0f90, MIXCOM_ID},
+	/* The FlashCOM cards */
+	{0x0304, FLASHCOM_ID},
+	{0x030c, FLASHCOM_ID},
+	{0x0314, FLASHCOM_ID},
+	{0x031c, FLASHCOM_ID},
+	{0x0324, FLASHCOM_ID},
+	{0x032c, FLASHCOM_ID},
+	{0x0334, FLASHCOM_ID},
+	{0x033c, FLASHCOM_ID},
+	{0x0344, FLASHCOM_ID},
+	{0x034c, FLASHCOM_ID},
+	{0x0354, FLASHCOM_ID},
+	{0x035c, FLASHCOM_ID},
+	{0x0364, FLASHCOM_ID},
+	{0x036c, FLASHCOM_ID},
+	{0x0374, FLASHCOM_ID},
+	{0x037c, FLASHCOM_ID},
+	/* The end of the list */
+	{0x0000, 0},
+};
+
+static void mixcomwd_timerfun(struct timer_list *unused);
+
+static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */
+
+static int watchdog_port;
+static int mixcomwd_timer_alive;
+static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun);
+static char expect_close;
+
+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 void mixcomwd_ping(void)
+{
+	outb_p(55, watchdog_port);
+	return;
+}
+
+static void mixcomwd_timerfun(struct timer_list *unused)
+{
+	mixcomwd_ping();
+	mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
+}
+
+/*
+ *	Allow only one person to hold it open
+ */
+
+static int mixcomwd_open(struct inode *inode, struct file *file)
+{
+	if (test_and_set_bit(0, &mixcomwd_opened))
+		return -EBUSY;
+
+	mixcomwd_ping();
+
+	if (nowayout)
+		/*
+		 * fops_get() code via open() has already done
+		 * a try_module_get() so it is safe to do the
+		 * __module_get().
+		 */
+		__module_get(THIS_MODULE);
+	else {
+		if (mixcomwd_timer_alive) {
+			del_timer(&mixcomwd_timer);
+			mixcomwd_timer_alive = 0;
+		}
+	}
+	return stream_open(inode, file);
+}
+
+static int mixcomwd_release(struct inode *inode, struct file *file)
+{
+	if (expect_close == 42) {
+		if (mixcomwd_timer_alive) {
+			pr_err("release called while internal timer alive\n");
+			return -EBUSY;
+		}
+		mixcomwd_timer_alive = 1;
+		mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
+	} else
+		pr_crit("WDT device closed unexpectedly.  WDT will not stop!\n");
+
+	clear_bit(0, &mixcomwd_opened);
+	expect_close = 0;
+	return 0;
+}
+
+
+static ssize_t mixcomwd_write(struct file *file, const char __user *data,
+						size_t len, loff_t *ppos)
+{
+	if (len) {
+		if (!nowayout) {
+			size_t i;
+
+			/* In case it was set long ago */
+			expect_close = 0;
+
+			for (i = 0; i != len; i++) {
+				char c;
+				if (get_user(c, data + i))
+					return -EFAULT;
+				if (c == 'V')
+					expect_close = 42;
+			}
+		}
+		mixcomwd_ping();
+	}
+	return len;
+}
+
+static long mixcomwd_ioctl(struct file *file,
+				unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	int __user *p = argp;
+	int status;
+	static const struct watchdog_info ident = {
+		.options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+		.firmware_version = 1,
+		.identity = "MixCOM watchdog",
+	};
+
+	switch (cmd) {
+	case WDIOC_GETSUPPORT:
+		if (copy_to_user(argp, &ident, sizeof(ident)))
+			return -EFAULT;
+		break;
+	case WDIOC_GETSTATUS:
+		status = mixcomwd_opened;
+		if (!nowayout)
+			status |= mixcomwd_timer_alive;
+		return put_user(status, p);
+	case WDIOC_GETBOOTSTATUS:
+		return put_user(0, p);
+	case WDIOC_KEEPALIVE:
+		mixcomwd_ping();
+		break;
+	default:
+		return -ENOTTY;
+	}
+	return 0;
+}
+
+static const struct file_operations mixcomwd_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= mixcomwd_write,
+	.unlocked_ioctl	= mixcomwd_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+	.open		= mixcomwd_open,
+	.release	= mixcomwd_release,
+};
+
+static struct miscdevice mixcomwd_miscdev = {
+	.minor	= WATCHDOG_MINOR,
+	.name	= "watchdog",
+	.fops	= &mixcomwd_fops,
+};
+
+static int __init checkcard(int port, int card_id)
+{
+	int id;
+
+	if (!request_region(port, 1, "MixCOM watchdog"))
+		return 0;
+
+	id = inb_p(port);
+	if (card_id == MIXCOM_ID)
+		id &= 0x3f;
+
+	if (id != card_id) {
+		release_region(port, 1);
+		return 0;
+	}
+	return 1;
+}
+
+static int __init mixcomwd_init(void)
+{
+	int i, ret, found = 0;
+
+	for (i = 0; !found && mixcomwd_io_info[i].ioport != 0; i++) {
+		if (checkcard(mixcomwd_io_info[i].ioport,
+			      mixcomwd_io_info[i].id)) {
+			found = 1;
+			watchdog_port = mixcomwd_io_info[i].ioport;
+		}
+	}
+
+	if (!found) {
+		pr_err("No card detected, or port not available\n");
+		return -ENODEV;
+	}
+
+	ret = misc_register(&mixcomwd_miscdev);
+	if (ret) {
+		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
+		       WATCHDOG_MINOR, ret);
+		goto error_misc_register_watchdog;
+	}
+
+	pr_info("MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",
+		VERSION, watchdog_port);
+
+	return 0;
+
+error_misc_register_watchdog:
+	release_region(watchdog_port, 1);
+	watchdog_port = 0x0000;
+	return ret;
+}
+
+static void __exit mixcomwd_exit(void)
+{
+	if (!nowayout) {
+		if (mixcomwd_timer_alive) {
+			pr_warn("I quit now, hardware will probably reboot!\n");
+			del_timer_sync(&mixcomwd_timer);
+			mixcomwd_timer_alive = 0;
+		}
+	}
+	misc_deregister(&mixcomwd_miscdev);
+	release_region(watchdog_port, 1);
+}
+
+module_init(mixcomwd_init);
+module_exit(mixcomwd_exit);
+
+MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>");
+MODULE_DESCRIPTION("MixCom Watchdog driver");
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");