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authorRalf Baechle <ralf@linux-mips.org>1997-09-12 01:29:55 +0000
committerRalf Baechle <ralf@linux-mips.org>1997-09-12 01:29:55 +0000
commit545f435ebcfd94a1e7c20b46efe81b4d6ac4e698 (patch)
treee9ce4bc598d06374bda906f18365984bf22a526a /drivers/char/acquirewdt.c
parent4291a610eef89d0d5c69d9a10ee6560e1aa36c74 (diff)
Merge with Linux 2.1.55. More bugfixes and goodies from my private
CVS archive.
Diffstat (limited to 'drivers/char/acquirewdt.c')
-rw-r--r--drivers/char/acquirewdt.c221
1 files changed, 221 insertions, 0 deletions
diff --git a/drivers/char/acquirewdt.c b/drivers/char/acquirewdt.c
new file mode 100644
index 000000000..aeb7b72fc
--- /dev/null
+++ b/drivers/char/acquirewdt.c
@@ -0,0 +1,221 @@
+/*
+ * Acquire Single Board Computer Watchdog Timer driver for Linux 2.1.x
+ *
+ * Based on wdt.c. Original copyright messages:
+ *
+ * (c) Copyright 1996 Alan Cox <alan@cymru.net>, All Rights Reserved.
+ * http://www.cymru.net
+ *
+ * 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>
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/malloc.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+
+static int acq_is_open=0;
+
+/*
+ * You must set these - there is no sane way to probe for this board.
+ */
+
+#define WDT_STOP 0x43
+#define WDT_START 0x443
+#define WATCHDOG_MINOR 130
+
+#define WD_TIMO (100*60) /* 1 minute */
+
+
+/*
+ * Kernel methods.
+ */
+
+
+static void acq_ping(void)
+{
+ /* Write a watchdog value */
+ inb_p(WDT_START);
+}
+
+static long acq_write(struct inode *inode, struct file *file, const char *buf, unsigned long count)
+{
+ if(count)
+ {
+ acq_ping();
+ return 1;
+ }
+ return 0;
+}
+
+static long acq_read(struct inode *inode, struct file *file, char *buf, unsigned long count)
+{
+ return -EINVAL;
+}
+
+
+
+static int acq_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ static struct watchdog_info ident=
+ {
+ WDIOF_KEEPALIVEPING, 1, "Acquire WDT"
+ };
+
+ switch(cmd)
+ {
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident)))
+ return -EFAULT;
+ break;
+
+ case WDIOC_GETSTATUS:
+ if (copy_to_user((int *)arg, &acq_is_open, sizeof(int)))
+ return -EFAULT;
+ break;
+
+ case WDIOC_KEEPALIVE:
+ acq_ping();
+ break;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static int acq_open(struct inode *inode, struct file *file)
+{
+ switch(MINOR(inode->i_rdev))
+ {
+ case WATCHDOG_MINOR:
+ if(acq_is_open)
+ return -EBUSY;
+ MOD_INC_USE_COUNT;
+ /*
+ * Activate
+ */
+
+ acq_is_open=1;
+ inb_p(WDT_START);
+ return 0;
+ default:
+ return -ENODEV;
+ }
+}
+
+static int acq_close(struct inode *inode, struct file *file)
+{
+ if(MINOR(inode->i_rdev)==WATCHDOG_MINOR)
+ {
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+ inb_p(WDT_STOP);
+#endif
+ acq_is_open=0;
+ }
+ MOD_DEC_USE_COUNT;
+ return 0;
+}
+
+/*
+ * Notifier for system down
+ */
+
+static int acq_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ if(code==SYS_DOWN || code==SYS_HALT)
+ {
+ /* Turn the card off */
+ inb_p(WDT_STOP);
+ }
+ return NOTIFY_DONE;
+}
+
+/*
+ * Kernel Interfaces
+ */
+
+
+static struct file_operations acq_fops = {
+ NULL,
+ acq_read,
+ acq_write,
+ NULL, /* No Readdir */
+ NULL, /* No Select */
+ acq_ioctl,
+ NULL, /* No mmap */
+ acq_open,
+ acq_close
+};
+
+static struct miscdevice acq_miscdev=
+{
+ WATCHDOG_MINOR,
+ "Acquire WDT",
+ &acq_fops
+};
+
+
+/*
+ * The WDT card needs to learn about soft shutdowns in order to
+ * turn the timebomb registers off.
+ */
+
+static struct notifier_block acq_notifier=
+{
+ acq_notify_sys,
+ NULL,
+ 0
+};
+
+#ifdef MODULE
+
+#define acq_init init_module
+
+void cleanup_module(void)
+{
+ misc_deregister(&acq_miscdev);
+ unregister_reboot_notifier(&acq_notifier);
+ release_region(WDT_STOP,1);
+ release_region(WDT_START,1);
+}
+
+#endif
+
+__initfunc(int acq_init(void))
+{
+ printk("WDT driver for Acquire single board computer initialising.\n");
+
+ misc_register(&acq_miscdev);
+ request_region(WDT_STOP, 1, "Acquire WDT");
+ request_region(WDT_START, 1, "Acquire WDT");
+ unregister_reboot_notifier(&acq_notifier);
+ return 0;
+}
+