[PATCH] char: Nano 7240 watchdog driver
Gilles GIGAN
djails at gmail.com
Fri Oct 5 22:10:23 CDT 2007
Hi everyone,
I thought I d submit this patch here first, to see if I m doing the right
thing. I do also have a couple of questions:
Below is the email I d like to send to the LKML for inclusion in the kernel.
- Is is appropriately formatted ? (I tried following the guidelines in
SubmittingPatches as closely as possible)
- is the patch correctly generated ? Are the changes to Kconfig and Makefile
to be included in the patch (like I did) ?
- Is the email title OK ? (not really sure what subsystem I should use:
"char" , "watchdog", "device drivers", ... ?)
All comments are welcome.
Cheers,
Gilles
from: Gilles Gigan <gilles.gigan at gmail.com>
Adds watchdog driver for EPIC Nano 7240 single board computers from IEI
Signed-off-by: Gilles Gigan <gilles.gigan at gmail.com>
---
diff -uprN -X linux-2.6.23-rc9/Documentation/dontdiff
linux-2.6.23-rc9/drivers/char/watchdog/Kconfig
linux-2.6.23-rc9-dirty/drivers/char/watchdog/Kconfig
--- linux-2.6.23-rc9/drivers/char/watchdog/Kconfig 2007-10-06 01:43:
44.000000000 +1000
+++ linux-2.6.23-rc9-dirty/drivers/char/watchdog/Kconfig 2007-10-06 02:23:
28.000000000 +1000
@@ -455,6 +455,19 @@ config SBC8360_WDT
Most people will say N.
+config SBC7240_WDT
+ tristate "SBC Nano 7240 Watchdog Timer"
+ depends on X86
+ ---help---
+ This is the driver for the hardware watchdog found on the IEI
+ single board computers EPIC Nano 7240 (and likely others). This
+ watchdog simply watches your kernel to make sure it doesn't freeze,
+ and if it does, it reboots your computer after a certain amount of
+ time.
+
+ To compile this driver as a module, choose M here: the
+ module will be called sbc7240_wdt.
+
config CPU5_WDT
tristate "SMA CPU5 Watchdog"
depends on X86
diff -uprN -X linux-2.6.23-rc9/Documentation/dontdiff
linux-2.6.23-rc9/drivers/char/watchdog/Makefile
linux-2.6.23-rc9-dirty/drivers/char/watchdog/Makefile
--- linux-2.6.23-rc9/drivers/char/watchdog/Makefile 2007-10-06 01:43:
44.000000000 +1000
+++ linux-2.6.23-rc9-dirty/drivers/char/watchdog/Makefile 2007-10-06 02:23:
28.000000000 +1000
@@ -71,6 +71,7 @@ obj-$(CONFIG_SCx200_WDT) += scx200_wdt.o
obj-$(CONFIG_PC87413_WDT) += pc87413_wdt.o
obj-$(CONFIG_60XX_WDT) += sbc60xxwdt.o
obj-$(CONFIG_SBC8360_WDT) += sbc8360.o
+obj-$(CONFIG_SBC7240_WDT) += sbc7240.o
obj-$(CONFIG_CPU5_WDT) += cpu5wdt.o
obj-$(CONFIG_SMSC37B787_WDT) += smsc37b787_wdt.o
obj-$(CONFIG_W83627HF_WDT) += w83627hf_wdt.o
diff -uprN -X linux-2.6.23-rc9/Documentation/dontdiff
linux-2.6.23-rc9/drivers/char/watchdog/sbc7240_wdt.c
linux-2.6.23-rc9-dirty/drivers/char/watchdog/sbc7240_wdt.c
--- linux-2.6.23-rc9/drivers/char/watchdog/sbc7240_wdt.c 1970-01-01 10:00:
00.000000000 +1000
+++ linux-2.6.23-rc9-dirty/drivers/char/watchdog/sbc7240_wdt.c 2007-10-06
02:23:28.000000000 +1000
@@ -0,0 +1,317 @@
+/*
+ * NANO7240 SBC Watchdog device driver
+ *
+ * Based on w83877f.c by Scott Jennings,
+ *
+ * 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.
+ *
+ * The authors do NOT admit liability nor provide warranty for
+ * any of this software. This material is provided "AS-IS" in
+ * the hope that it may be useful for others.
+ *
+ * (c) Copyright 2007 Gilles GIGAN <gilles.gigan at gmail.com>
+ *
+ * 10/01- 2007 [Initial revision]
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/jiffies.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 <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+
+#define PREFIX "sbc7240_wdt: "
+
+#define ENABLE_SBC7240_PORT 0x443
+#define DISABLE_SBC7240_PORT 0x043
+#define SET_TIMEOUT_SBC7240_PORT ENABLE_SBC7240_PORT
+#define WDT_MAGIC_CHAR 'V'
+
+#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
+#define WATCHDOG_MAX_TIMEOUT 255
+static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<="
+ __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) ", default="
+ __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+#define NOWAYOUT 1
+#else
+#define NOWAYOUT 0
+#endif
+static int nowayout = NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Disable watchdog when closing device file");
+
+#define OPEN_STATUS_BIT 0
+#define ENABLED_STATUS_BIT 1
+static unsigned long wdt_status = 0;
+
+/*
+ * Utility routines
+ */
+
+static void wdt_disable(void)
+{
+ /* disable the watchdog */
+ if (test_and_clear_bit(ENABLED_STATUS_BIT, &wdt_status)) {
+ inb_p(DISABLE_SBC7240_PORT);
+ printk(KERN_INFO PREFIX "Watchdog timer is now disabled.\n");
+ }
+}
+
+static void wdt_enable(void)
+{
+ /* enable the watchdog */
+ if (!test_and_set_bit(ENABLED_STATUS_BIT, &wdt_status)) {
+ inb_p(ENABLE_SBC7240_PORT);
+ printk(KERN_INFO PREFIX "Watchdog timer is now enabled.\n");
+ }
+}
+
+static int wdt_set_timeout(int t)
+{
+ if (t < 1 || t > WATCHDOG_MAX_TIMEOUT) {
+ printk(KERN_ERR PREFIX "timeout value must be 1<=x<=%d\n",
+ WATCHDOG_MAX_TIMEOUT);
+ return -1;
+ }
+ /* set the timeout */
+ outb_p((unsigned)t, ENABLE_SBC7240_PORT);
+ printk(KERN_INFO PREFIX "timeout set to %d seconds\n", t);
+ return 0;
+}
+
+/* Whack the dog */
+static inline void wdt_keepalive(void)
+{
+ if (test_bit(ENABLED_STATUS_BIT, &wdt_status))
+ inb_p(ENABLE_SBC7240_PORT);
+}
+
+/*
+ * /dev/watchdog handling
+ */
+static ssize_t fop_write(struct file *file, const char __user * buf,
+ size_t count, loff_t * ppos)
+{
+ size_t i;
+ char c;
+ int got_magic_char = 0;
+
+ // is there a magic char ?
+ for (i = 0; i != count; i++) {
+ if (get_user(c, buf + i))
+ return -EFAULT;
+ if (c == WDT_MAGIC_CHAR) {
+ got_magic_char = 1;
+ break;
+ }
+ }
+
+ if (got_magic_char)
+ wdt_disable();
+ else
+ wdt_keepalive();
+
+ return count;
+}
+
+static int fop_open(struct inode *inode, struct file *file)
+{
+ if (test_and_set_bit(OPEN_STATUS_BIT, &wdt_status))
+ return -EBUSY;
+
+ return nonseekable_open(inode, file);
+}
+
+static int fop_close(struct inode *inode, struct file *file)
+{
+ if (!nowayout)
+ wdt_disable();
+
+ clear_bit(OPEN_STATUS_BIT, &wdt_status);
+ return 0;
+}
+
+static int fop_ioctl(struct inode *inode, struct file *file, unsigned int
cmd,
+ unsigned long arg)
+{
+ static struct watchdog_info ident = {
+ .options =
+ WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
+ .firmware_version = 1,
+ .identity = "SBC7240",
+ };
+
+ if ((_IOC_DIR(cmd) & _IOC_READ) &&
+ (!access_ok(VERIFY_WRITE, (void __user *)arg, _IOC_SIZE(cmd))))
+ return -EFAULT;
+ if ((_IOC_DIR(cmd) & _IOC_WRITE) &&
+ (!access_ok(VERIFY_READ, (void __user *)arg, _IOC_SIZE(cmd))))
+ return -EFAULT;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return __copy_to_user((void __user *)arg,
+ &ident, sizeof(ident)) ? -EFAULT : 0;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return __put_user(0, (int __user *)arg);
+ case WDIOC_KEEPALIVE:
+ wdt_keepalive();
+ return 0;
+ case WDIOC_SETOPTIONS:{
+ int retval = -EINVAL;
+
+ if (arg & WDIOS_DISABLECARD) {
+ wdt_disable();
+ retval = 0;
+ }
+
+ if (arg & WDIOS_ENABLECARD) {
+ wdt_enable();
+ retval = 0;
+ }
+
+ return retval;
+ }
+ case WDIOC_SETTIMEOUT:{
+ int new_timeout;
+
+ if (__get_user(new_timeout, (int __user *)arg))
+ return -EFAULT;
+
+ if (wdt_set_timeout(new_timeout))
+ return -EINVAL;
+
+ timeout = new_timeout;
+ return 0;
+ }
+ case WDIOC_GETTIMEOUT:
+ return __put_user(timeout, (int __user *)arg);
+ default:
+ return -ENOTTY;
+ }
+}
+
+static const struct file_operations wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = fop_write,
+ .open = fop_open,
+ .release = fop_close,
+ .ioctl = fop_ioctl,
+};
+
+static struct miscdevice wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &wdt_fops,
+};
+
+/*
+ * 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();
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block wdt_notifier = {
+ .notifier_call = wdt_notify_sys,
+};
+
+static void __exit sbc7240_wdt_unload(void)
+{
+ printk(KERN_INFO PREFIX "Removing watchog\n");
+ misc_deregister(&wdt_miscdev);
+
+ unregister_reboot_notifier(&wdt_notifier);
+// release_region(DISABLE_SBC7240_PORT,1);
+ release_region(ENABLE_SBC7240_PORT, 1);
+}
+
+static int __init sbc7240_wdt_init(void)
+{
+ int rc = -EBUSY;
+
+ if (!request_region(ENABLE_SBC7240_PORT, 1, "SBC7240 WDT")) {
+ printk(KERN_ERR PREFIX "I/O address 0x%04x already in use\n",
+ ENABLE_SBC7240_PORT);
+ rc = -EIO;
+ goto err_out;
+ }
+
+ //The IO port 0x043 is already claimed by the system timer
+/* if (!request_region(DISABLE_SBC7240_PORT, 1, "SBC7240 WDT"))
+ {
+ printk(KERN_ERR "I/O address 0x%04x already in use\n",
+ DISABLE_SBC7240_PORT);
+ rc = -EIO;
+ goto err_out_region1;
+ }
+*/
+ rc = misc_register(&wdt_miscdev);
+ if (rc) {
+ printk(KERN_ERR PREFIX
+ "cannot register miscdev on minor=%d (err=%d)\n",
+ wdt_miscdev.minor, rc);
+ goto err_out_region2;
+ }
+
+ rc = register_reboot_notifier(&wdt_notifier);
+ if (rc) {
+ printk(KERN_ERR PREFIX
+ "cannot register reboot notifier (err=%d)\n", rc);
+ goto err_out_miscdev;
+ }
+
+ if (timeout < 1 || timeout > WATCHDOG_MAX_TIMEOUT) {
+ timeout = WATCHDOG_TIMEOUT;
+ printk(KERN_INFO PREFIX
+ "timeout value must be 1<=x<=%d, using %d\n",
+ WATCHDOG_MAX_TIMEOUT, timeout);
+ }
+ wdt_set_timeout(timeout);
+
+ printk(KERN_INFO PREFIX
+ "Watchdog driver for SBC7240 initialised (nowayout=%d)\n",
nowayout);
+
+ return 0;
+
+ err_out_miscdev:
+ misc_deregister(&wdt_miscdev);
+ err_out_region2:
+// release_region(DISABLE_SBC7240_PORT,1);
+//err_out_region1:
+ release_region(ENABLE_SBC7240_PORT, 1);
+ err_out:
+ return rc;
+}
+
+module_init(sbc7240_wdt_init);
+module_exit(sbc7240_wdt_unload);
+
+MODULE_AUTHOR("Gilles Gigan");
+MODULE_DESCRIPTION("Watchdog device driver for single board computer EPIC
Nano 7240 from iEi");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
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