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authorLinus Torvalds <torvalds@g5.osdl.org>2006-04-02 22:01:11 +0200
committerLinus Torvalds <torvalds@g5.osdl.org>2006-04-02 22:01:11 +0200
commit7f344f0aa7d4ec0e4c1c676329aff1353f90fb38 (patch)
tree955347ebf22af5f7479ea9b01e8e8f14c2c426c0 /drivers
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial (diff)
parent[WATCHDOG] at91_wdt.c - Atmel AT91RM9200 watchdog driver (diff)
downloadlinux-7f344f0aa7d4ec0e4c1c676329aff1353f90fb38.tar.xz
linux-7f344f0aa7d4ec0e4c1c676329aff1353f90fb38.zip
Merge master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog
* master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog: [WATCHDOG] at91_wdt.c - Atmel AT91RM9200 watchdog driver [WATCHDOG] pcwd_usb.c: fix a NULL pointer dereference [WATCHDOG] pcwd.c sprintf/strcpy fix [WATCHDOG] pcwd.c general clean-up after patches [WATCHDOG] pcwd.c add debug info [WATCHDOG] pcwd.c pcwd_cleanup_module patch [WATCHDOG] pcwd.c firmware-info patch [WATCHDOG] pcwd.c control status patch
Diffstat (limited to 'drivers')
-rw-r--r--drivers/char/watchdog/Kconfig7
-rw-r--r--drivers/char/watchdog/Makefile1
-rw-r--r--drivers/char/watchdog/at91_wdt.c228
-rw-r--r--drivers/char/watchdog/pcwd.c137
-rw-r--r--drivers/char/watchdog/pcwd_usb.c3
5 files changed, 340 insertions, 36 deletions
diff --git a/drivers/char/watchdog/Kconfig b/drivers/char/watchdog/Kconfig
index 16e99db2e12d..d53f664a4dd8 100644
--- a/drivers/char/watchdog/Kconfig
+++ b/drivers/char/watchdog/Kconfig
@@ -60,6 +60,13 @@ config SOFT_WATCHDOG
# ARM Architecture
+config AT91_WATCHDOG
+ tristate "AT91RM9200 watchdog"
+ depends on WATCHDOG && ARCH_AT91RM9200
+ help
+ Watchdog timer embedded into AT91RM9200 chips. This will reboot your
+ system when the timeout is reached.
+
config 21285_WATCHDOG
tristate "DC21285 watchdog"
depends on WATCHDOG && FOOTBRIDGE
diff --git a/drivers/char/watchdog/Makefile b/drivers/char/watchdog/Makefile
index d6f27fde9905..6ab77b61a643 100644
--- a/drivers/char/watchdog/Makefile
+++ b/drivers/char/watchdog/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_WDTPCI) += wdt_pci.o
obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.o
# ARM Architecture
+obj-$(CONFIG_AT91_WATCHDOG) += at91_wdt.o
obj-$(CONFIG_21285_WATCHDOG) += wdt285.o
obj-$(CONFIG_977_WATCHDOG) += wdt977.o
obj-$(CONFIG_IXP2000_WATCHDOG) += ixp2000_wdt.o
diff --git a/drivers/char/watchdog/at91_wdt.c b/drivers/char/watchdog/at91_wdt.c
new file mode 100644
index 000000000000..ac83bc4b019a
--- /dev/null
+++ b/drivers/char/watchdog/at91_wdt.c
@@ -0,0 +1,228 @@
+/*
+ * Watchdog driver for Atmel AT91RM9200 (Thunder)
+ *
+ * Copyright (C) 2003 SAN People (Pty) Ltd
+ *
+ * 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.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <asm/bitops.h>
+#include <asm/uaccess.h>
+
+
+#define WDT_DEFAULT_TIME 5 /* 5 seconds */
+#define WDT_MAX_TIME 256 /* 256 seconds */
+
+static int wdt_time = WDT_DEFAULT_TIME;
+static int nowayout = WATCHDOG_NOWAYOUT;
+
+module_param(wdt_time, int, 0);
+MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="__MODULE_STRING(WDT_DEFAULT_TIME) ")");
+
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+
+static unsigned long at91wdt_busy;
+
+/* ......................................................................... */
+
+/*
+ * Disable the watchdog.
+ */
+static void inline at91_wdt_stop(void)
+{
+ at91_sys_write(AT91_ST_WDMR, AT91_ST_EXTEN);
+}
+
+/*
+ * Enable and reset the watchdog.
+ */
+static void inline at91_wdt_start(void)
+{
+ at91_sys_write(AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN | (((65536 * wdt_time) >> 8) & AT91_ST_WDV));
+ at91_sys_write(AT91_ST_CR, AT91_ST_WDRST);
+}
+
+/*
+ * Reload the watchdog timer. (ie, pat the watchdog)
+ */
+static void inline at91_wdt_reload(void)
+{
+ at91_sys_write(AT91_ST_CR, AT91_ST_WDRST);
+}
+
+/* ......................................................................... */
+
+/*
+ * Watchdog device is opened, and watchdog starts running.
+ */
+static int at91_wdt_open(struct inode *inode, struct file *file)
+{
+ if (test_and_set_bit(0, &at91wdt_busy))
+ return -EBUSY;
+
+ at91_wdt_start();
+ return nonseekable_open(inode, file);
+}
+
+/*
+ * Close the watchdog device.
+ * If CONFIG_WATCHDOG_NOWAYOUT is NOT defined then the watchdog is also
+ * disabled.
+ */
+static int at91_wdt_close(struct inode *inode, struct file *file)
+{
+ if (!nowayout)
+ at91_wdt_stop(); /* Disable the watchdog when file is closed */
+
+ clear_bit(0, &at91wdt_busy);
+ return 0;
+}
+
+/*
+ * Change the watchdog time interval.
+ */
+static int at91_wdt_settimeout(int new_time)
+{
+ /*
+ * All counting occurs at SLOW_CLOCK / 128 = 0.256 Hz
+ *
+ * Since WDV is a 16-bit counter, the maximum period is
+ * 65536 / 0.256 = 256 seconds.
+ */
+ if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
+ return -EINVAL;
+
+ /* Set new watchdog time. It will be used when at91_wdt_start() is called. */
+ wdt_time = new_time;
+ return 0;
+}
+
+static struct watchdog_info at91_wdt_info = {
+ .identity = "at91 watchdog",
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+};
+
+/*
+ * Handle commands from user-space.
+ */
+static int at91_wdt_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ int __user *p = argp;
+ int new_value;
+
+ switch(cmd) {
+ case WDIOC_KEEPALIVE:
+ at91_wdt_reload(); /* pat the watchdog */
+ return 0;
+
+ case WDIOC_GETSUPPORT:
+ return copy_to_user(argp, &at91_wdt_info, sizeof(at91_wdt_info)) ? -EFAULT : 0;
+
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_value, p))
+ return -EFAULT;
+
+ if (at91_wdt_settimeout(new_value))
+ return -EINVAL;
+
+ /* Enable new time value */
+ at91_wdt_start();
+
+ /* Return current value */
+ return put_user(wdt_time, p);
+
+ case WDIOC_GETTIMEOUT:
+ return put_user(wdt_time, p);
+
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, p);
+
+ case WDIOC_SETOPTIONS:
+ if (get_user(new_value, p))
+ return -EFAULT;
+
+ if (new_value & WDIOS_DISABLECARD)
+ at91_wdt_stop();
+ if (new_value & WDIOS_ENABLECARD)
+ at91_wdt_start();
+ return 0;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+/*
+ * Pat the watchdog whenever device is written to.
+ */
+static ssize_t at91_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
+{
+ at91_wdt_reload(); /* pat the watchdog */
+ return len;
+}
+
+/* ......................................................................... */
+
+static struct file_operations at91wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .ioctl = at91_wdt_ioctl,
+ .open = at91_wdt_open,
+ .release = at91_wdt_close,
+ .write = at91_wdt_write,
+};
+
+static struct miscdevice at91wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &at91wdt_fops,
+};
+
+static int __init at91_wdt_init(void)
+{
+ int res;
+
+ /* Check that the heartbeat value is within range; if not reset to the default */
+ if (at91_wdt_settimeout(wdt_time)) {
+ at91_wdt_settimeout(WDT_DEFAULT_TIME);
+ printk(KERN_INFO "at91_wdt: wdt_time value must be 1 <= wdt_time <= 256, using %d\n", wdt_time);
+ }
+
+ res = misc_register(&at91wdt_miscdev);
+ if (res)
+ return res;
+
+ printk("AT91 Watchdog Timer enabled (%d seconds, nowayout=%d)\n", wdt_time, nowayout);
+ return 0;
+}
+
+static void __exit at91_wdt_exit(void)
+{
+ misc_deregister(&at91wdt_miscdev);
+}
+
+module_init(at91_wdt_init);
+module_exit(at91_wdt_exit);
+
+MODULE_AUTHOR("Andrew Victor");
+MODULE_DESCRIPTION("Watchdog driver for Atmel AT91RM9200");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
diff --git a/drivers/char/watchdog/pcwd.c b/drivers/char/watchdog/pcwd.c
index 8d6b249ad66b..6d44ca68312d 100644
--- a/drivers/char/watchdog/pcwd.c
+++ b/drivers/char/watchdog/pcwd.c
@@ -66,15 +66,13 @@
#include <linux/fs.h> /* For file operations */
#include <linux/ioport.h> /* For io-port access */
#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
-#include <linux/sched.h> /* TASK_INTERRUPTIBLE, set_current_state() and friends */
-#include <linux/slab.h> /* For kmalloc */
#include <asm/uaccess.h> /* For copy_to_user/put_user/... */
#include <asm/io.h> /* For inb/outb/... */
/* Module and version information */
-#define WATCHDOG_VERSION "1.16"
-#define WATCHDOG_DATE "03 Jan 2006"
+#define WATCHDOG_VERSION "1.17"
+#define WATCHDOG_DATE "12 Feb 2006"
#define WATCHDOG_DRIVER_NAME "ISA-PC Watchdog"
#define WATCHDOG_NAME "pcwd"
#define PFX WATCHDOG_NAME ": "
@@ -96,15 +94,19 @@
* PCI-PC Watchdog card.
*/
/* Port 1 : Control Status #1 for the PC Watchdog card, revision A. */
-#define WD_WDRST 0x01 /* Previously reset state */
-#define WD_T110 0x02 /* Temperature overheat sense */
-#define WD_HRTBT 0x04 /* Heartbeat sense */
-#define WD_RLY2 0x08 /* External relay triggered */
-#define WD_SRLY2 0x80 /* Software external relay triggered */
+#define WD_WDRST 0x01 /* Previously reset state */
+#define WD_T110 0x02 /* Temperature overheat sense */
+#define WD_HRTBT 0x04 /* Heartbeat sense */
+#define WD_RLY2 0x08 /* External relay triggered */
+#define WD_SRLY2 0x80 /* Software external relay triggered */
/* Port 1 : Control Status #1 for the PC Watchdog card, revision C. */
-#define WD_REVC_WTRP 0x01 /* Watchdog Trip status */
-#define WD_REVC_HRBT 0x02 /* Watchdog Heartbeat */
-#define WD_REVC_TTRP 0x04 /* Temperature Trip status */
+#define WD_REVC_WTRP 0x01 /* Watchdog Trip status */
+#define WD_REVC_HRBT 0x02 /* Watchdog Heartbeat */
+#define WD_REVC_TTRP 0x04 /* Temperature Trip status */
+#define WD_REVC_RL2A 0x08 /* Relay 2 activated by on-board processor */
+#define WD_REVC_RL1A 0x10 /* Relay 1 active */
+#define WD_REVC_R2DS 0x40 /* Relay 2 disable */
+#define WD_REVC_RLY2 0x80 /* Relay 2 activated? */
/* Port 2 : Control Status #2 */
#define WD_WDIS 0x10 /* Watchdog Disabled */
#define WD_ENTP 0x20 /* Watchdog Enable Temperature Trip */
@@ -122,9 +124,14 @@
#define CMD_ISA_VERSION_HUNDRETH 0x03
#define CMD_ISA_VERSION_MINOR 0x04
#define CMD_ISA_SWITCH_SETTINGS 0x05
+#define CMD_ISA_RESET_PC 0x06
+#define CMD_ISA_ARM_0 0x07
+#define CMD_ISA_ARM_30 0x08
+#define CMD_ISA_ARM_60 0x09
#define CMD_ISA_DELAY_TIME_2SECS 0x0A
#define CMD_ISA_DELAY_TIME_4SECS 0x0B
#define CMD_ISA_DELAY_TIME_8SECS 0x0C
+#define CMD_ISA_RESET_RELAYS 0x0D
/*
* We are using an kernel timer to do the pinging of the watchdog
@@ -142,6 +149,7 @@ static atomic_t open_allowed = ATOMIC_INIT(1);
static char expect_close;
static int temp_panic;
static struct { /* this is private data for each ISA-PC watchdog card */
+ char fw_ver_str[6]; /* The cards firmware version */
int revision; /* The card's revision */
int supports_temp; /* Wether or not the card has a temperature device */
int command_mode; /* Wether or not the card is in command mode */
@@ -153,6 +161,13 @@ static struct { /* this is private data for each ISA-PC watchdog card */
} pcwd_private;
/* module parameters */
+#define QUIET 0 /* Default */
+#define VERBOSE 1 /* Verbose */
+#define DEBUG 2 /* print fancy stuff too */
+static int debug = QUIET;
+module_param(debug, int, 0);
+MODULE_PARM_DESC(debug, "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");
+
#define WATCHDOG_HEARTBEAT 60 /* 60 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
@@ -172,6 +187,10 @@ static int send_isa_command(int cmd)
int control_status;
int port0, last_port0; /* Double read for stabilising */
+ if (debug >= DEBUG)
+ printk(KERN_DEBUG PFX "sending following data cmd=0x%02x\n",
+ cmd);
+
/* The WCMD bit must be 1 and the command is only 4 bits in size */
control_status = (cmd & 0x0F) | WD_WCMD;
outb_p(control_status, pcwd_private.io_addr + 2);
@@ -188,6 +207,10 @@ static int send_isa_command(int cmd)
udelay (250);
}
+ if (debug >= DEBUG)
+ printk(KERN_DEBUG PFX "received following data for cmd=0x%02x: port0=0x%02x last_port0=0x%02x\n",
+ cmd, port0, last_port0);
+
return port0;
}
@@ -214,6 +237,10 @@ static int set_command_mode(void)
spin_unlock(&pcwd_private.io_lock);
pcwd_private.command_mode = found;
+ if (debug >= DEBUG)
+ printk(KERN_DEBUG PFX "command_mode=%d\n",
+ pcwd_private.command_mode);
+
return(found);
}
@@ -226,6 +253,10 @@ static void unset_command_mode(void)
spin_unlock(&pcwd_private.io_lock);
pcwd_private.command_mode = 0;
+
+ if (debug >= DEBUG)
+ printk(KERN_DEBUG PFX "command_mode=%d\n",
+ pcwd_private.command_mode);
}
static inline void pcwd_check_temperature_support(void)
@@ -234,27 +265,22 @@ static inline void pcwd_check_temperature_support(void)
pcwd_private.supports_temp = 1;
}
-static inline char *get_firmware(void)
+static inline void pcwd_get_firmware(void)
{
int one, ten, hund, minor;
- char *ret;
- ret = kmalloc(6, GFP_KERNEL);
- if(ret == NULL)
- return NULL;
+ strcpy(pcwd_private.fw_ver_str, "ERROR");
if (set_command_mode()) {
one = send_isa_command(CMD_ISA_VERSION_INTEGER);
ten = send_isa_command(CMD_ISA_VERSION_TENTH);
hund = send_isa_command(CMD_ISA_VERSION_HUNDRETH);
minor = send_isa_command(CMD_ISA_VERSION_MINOR);
- sprintf(ret, "%c.%c%c%c", one, ten, hund, minor);
+ sprintf(pcwd_private.fw_ver_str, "%c.%c%c%c", one, ten, hund, minor);
}
- else
- sprintf(ret, "ERROR");
-
unset_command_mode();
- return(ret);
+
+ return;
}
static inline int pcwd_get_option_switches(void)
@@ -272,17 +298,15 @@ static inline int pcwd_get_option_switches(void)
static void pcwd_show_card_info(void)
{
- char *firmware;
int option_switches;
/* Get some extra info from the hardware (in command/debug/diag mode) */
if (pcwd_private.revision == PCWD_REVISION_A)
printk(KERN_INFO PFX "ISA-PC Watchdog (REV.A) detected at port 0x%04x\n", pcwd_private.io_addr);
else if (pcwd_private.revision == PCWD_REVISION_C) {
- firmware = get_firmware();
+ pcwd_get_firmware();
printk(KERN_INFO PFX "ISA-PC Watchdog (REV.C) detected at port 0x%04x (Firmware version: %s)\n",
- pcwd_private.io_addr, firmware);
- kfree(firmware);
+ pcwd_private.io_addr, pcwd_private.fw_ver_str);
option_switches = pcwd_get_option_switches();
printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
option_switches,
@@ -362,6 +386,10 @@ static int pcwd_start(void)
return -EIO;
}
}
+
+ if (debug >= VERBOSE)
+ printk(KERN_DEBUG PFX "Watchdog started\n");
+
return 0;
}
@@ -386,6 +414,10 @@ static int pcwd_stop(void)
return -EIO;
}
}
+
+ if (debug >= VERBOSE)
+ printk(KERN_DEBUG PFX "Watchdog stopped\n");
+
return 0;
}
@@ -393,6 +425,10 @@ static int pcwd_keepalive(void)
{
/* user land ping */
pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
+
+ if (debug >= DEBUG)
+ printk(KERN_DEBUG PFX "Watchdog keepalive signal send\n");
+
return 0;
}
@@ -402,12 +438,17 @@ static int pcwd_set_heartbeat(int t)
return -EINVAL;
heartbeat = t;
+
+ if (debug >= VERBOSE)
+ printk(KERN_DEBUG PFX "New heartbeat: %d\n",
+ heartbeat);
+
return 0;
}
static int pcwd_get_status(int *status)
{
- int card_status;
+ int control_status;
*status=0;
spin_lock(&pcwd_private.io_lock);
@@ -415,37 +456,39 @@ static int pcwd_get_status(int *status)
/* Rev A cards return status information from
* the base register, which is used for the
* temperature in other cards. */
- card_status = inb(pcwd_private.io_addr);
+ control_status = inb(pcwd_private.io_addr);
else {
/* Rev C cards return card status in the base
* address + 1 register. And use different bits
* to indicate a card initiated reset, and an
* over-temperature condition. And the reboot
* status can be reset. */
- card_status = inb(pcwd_private.io_addr + 1);
+ control_status = inb(pcwd_private.io_addr + 1);
}
spin_unlock(&pcwd_private.io_lock);
if (pcwd_private.revision == PCWD_REVISION_A) {
- if (card_status & WD_WDRST)
+ if (control_status & WD_WDRST)
*status |= WDIOF_CARDRESET;
- if (card_status & WD_T110) {
+ if (control_status & WD_T110) {
*status |= WDIOF_OVERHEAT;
if (temp_panic) {
printk (KERN_INFO PFX "Temperature overheat trip!\n");
kernel_power_off();
+ /* or should we just do a: panic(PFX "Temperature overheat trip!\n"); */
}
}
} else {
- if (card_status & WD_REVC_WTRP)
+ if (control_status & WD_REVC_WTRP)
*status |= WDIOF_CARDRESET;
- if (card_status & WD_REVC_TTRP) {
+ if (control_status & WD_REVC_TTRP) {
*status |= WDIOF_OVERHEAT;
if (temp_panic) {
printk (KERN_INFO PFX "Temperature overheat trip!\n");
kernel_power_off();
+ /* or should we just do a: panic(PFX "Temperature overheat trip!\n"); */
}
}
}
@@ -455,9 +498,25 @@ static int pcwd_get_status(int *status)
static int pcwd_clear_status(void)
{
+ int control_status;
+
if (pcwd_private.revision == PCWD_REVISION_C) {
spin_lock(&pcwd_private.io_lock);
- outb_p(0x00, pcwd_private.io_addr + 1); /* clear reset status */
+
+ if (debug >= VERBOSE)
+ printk(KERN_INFO PFX "clearing watchdog trip status\n");
+
+ control_status = inb_p(pcwd_private.io_addr + 1);
+
+ if (debug >= DEBUG) {
+ printk(KERN_DEBUG PFX "status was: 0x%02x\n", control_status);
+ printk(KERN_DEBUG PFX "sending: 0x%02x\n",
+ (control_status & WD_REVC_R2DS));
+ }
+
+ /* clear reset status & Keep Relay 2 disable state as it is */
+ outb_p((control_status & WD_REVC_R2DS), pcwd_private.io_addr + 1);
+
spin_unlock(&pcwd_private.io_lock);
}
return 0;
@@ -481,6 +540,11 @@ static int pcwd_get_temperature(int *temperature)
*temperature = ((inb(pcwd_private.io_addr)) * 9 / 5) + 32;
spin_unlock(&pcwd_private.io_lock);
+ if (debug >= DEBUG) {
+ printk(KERN_DEBUG PFX "temperature is: %d F\n",
+ *temperature);
+ }
+
return 0;
}
@@ -599,6 +663,8 @@ static ssize_t pcwd_write(struct file *file, const char __user *buf, size_t len,
static int pcwd_open(struct inode *inode, struct file *file)
{
if (!atomic_dec_and_test(&open_allowed) ) {
+ if (debug >= VERBOSE)
+ printk(KERN_ERR PFX "Attempt to open already opened device.\n");
atomic_inc( &open_allowed );
return -EBUSY;
}
@@ -922,7 +988,8 @@ static void __exit pcwd_cleanup_module(void)
{
if (pcwd_private.io_addr)
pcwatchdog_exit();
- return;
+
+ printk(KERN_INFO PFX "Watchdog Module Unloaded.\n");
}
module_init(pcwd_init_module);
diff --git a/drivers/char/watchdog/pcwd_usb.c b/drivers/char/watchdog/pcwd_usb.c
index 2700c5c45b8a..3fdfda9324fa 100644
--- a/drivers/char/watchdog/pcwd_usb.c
+++ b/drivers/char/watchdog/pcwd_usb.c
@@ -705,7 +705,8 @@ err_out_misc_deregister:
err_out_unregister_reboot:
unregister_reboot_notifier(&usb_pcwd_notifier);
error:
- usb_pcwd_delete (usb_pcwd);
+ if (usb_pcwd)
+ usb_pcwd_delete(usb_pcwd);
usb_pcwd_device = NULL;
return retval;
}