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path: root/drivers/watchdog/it8712f_wdt.c
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Diffstat (limited to 'drivers/watchdog/it8712f_wdt.c')
-rw-r--r--drivers/watchdog/it8712f_wdt.c204
1 files changed, 108 insertions, 96 deletions
diff --git a/drivers/watchdog/it8712f_wdt.c b/drivers/watchdog/it8712f_wdt.c
index 445b7e81211..41b3979a9d8 100644
--- a/drivers/watchdog/it8712f_wdt.c
+++ b/drivers/watchdog/it8712f_wdt.c
@@ -20,6 +20,8 @@
* software is provided AS-IS with no warranties.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
@@ -28,31 +30,29 @@
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/fs.h>
-#include <linux/pci.h>
#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
-#include <asm/uaccess.h>
-#include <asm/io.h>
-
+#define DEBUG
#define NAME "it8712f_wdt"
MODULE_AUTHOR("Jorge Boncompte - DTI2 <jorge@dti2.net>");
MODULE_DESCRIPTION("IT8712F Watchdog Driver");
MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
static int max_units = 255;
static int margin = 60; /* in seconds */
module_param(margin, int, 0);
MODULE_PARM_DESC(margin, "Watchdog margin in seconds");
-static int nowayout = WATCHDOG_NOWAYOUT;
-module_param(nowayout, int, 0);
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
-static struct semaphore it8712f_wdt_sem;
+static unsigned long wdt_open;
static unsigned expect_close;
-static spinlock_t io_lock;
static unsigned char revision;
/* Dog Food address - We use the game port address */
@@ -70,38 +70,43 @@ static unsigned short address;
#define IT8712F_DEVID 0x8712
#define LDN_GPIO 0x07 /* GPIO and Watch Dog Timer */
-#define LDN_GAME 0x09 /* Game Port */
+#define LDN_GAME 0x09 /* Game Port */
#define WDT_CONTROL 0x71 /* WDT Register: Control */
#define WDT_CONFIG 0x72 /* WDT Register: Configuration */
#define WDT_TIMEOUT 0x73 /* WDT Register: Timeout Value */
-#define WDT_RESET_GAME 0x10
-#define WDT_RESET_KBD 0x20
-#define WDT_RESET_MOUSE 0x40
-#define WDT_RESET_CIR 0x80
+#define WDT_RESET_GAME 0x10 /* Reset timer on read or write to game port */
+#define WDT_RESET_KBD 0x20 /* Reset timer on keyboard interrupt */
+#define WDT_RESET_MOUSE 0x40 /* Reset timer on mouse interrupt */
+#define WDT_RESET_CIR 0x80 /* Reset timer on consumer IR interrupt */
#define WDT_UNIT_SEC 0x80 /* If 0 in MINUTES */
-#define WDT_OUT_PWROK 0x10
-#define WDT_OUT_KRST 0x40
+#define WDT_OUT_PWROK 0x10 /* Pulse PWROK on timeout */
+#define WDT_OUT_KRST 0x40 /* Pulse reset on timeout */
+
+static int wdt_control_reg = WDT_RESET_GAME;
+module_param(wdt_control_reg, int, 0);
+MODULE_PARM_DESC(wdt_control_reg, "Value to write to watchdog control "
+ "register. The default WDT_RESET_GAME resets the timer on "
+ "game port reads that this driver generates. You can also "
+ "use KBD, MOUSE or CIR if you have some external way to "
+ "generate those interrupts.");
-static int
-superio_inb(int reg)
+static int superio_inb(int reg)
{
outb(reg, REG);
return inb(VAL);
}
-static void
-superio_outb(int val, int reg)
+static void superio_outb(int val, int reg)
{
outb(reg, REG);
outb(val, VAL);
}
-static int
-superio_inw(int reg)
+static int superio_inw(int reg)
{
int val;
outb(reg++, REG);
@@ -111,39 +116,41 @@ superio_inw(int reg)
return val;
}
-static inline void
-superio_select(int ldn)
+static inline void superio_select(int ldn)
{
outb(LDN, REG);
outb(ldn, VAL);
}
-static inline void
-superio_enter(void)
+static inline int superio_enter(void)
{
- spin_lock(&io_lock);
+ /*
+ * Try to reserve REG and REG + 1 for exclusive access.
+ */
+ if (!request_muxed_region(REG, 2, NAME))
+ return -EBUSY;
+
outb(0x87, REG);
outb(0x01, REG);
outb(0x55, REG);
outb(0x55, REG);
+ return 0;
}
-static inline void
-superio_exit(void)
+static inline void superio_exit(void)
{
outb(0x02, REG);
outb(0x02, VAL);
- spin_unlock(&io_lock);
+ release_region(REG, 2);
}
-static inline void
-it8712f_wdt_ping(void)
+static inline void it8712f_wdt_ping(void)
{
- inb(address);
+ if (wdt_control_reg & WDT_RESET_GAME)
+ inb(address);
}
-static void
-it8712f_wdt_update_margin(void)
+static void it8712f_wdt_update_margin(void)
{
int config = WDT_OUT_KRST | WDT_OUT_PWROK;
int units = margin;
@@ -153,10 +160,10 @@ it8712f_wdt_update_margin(void)
*/
if (units <= max_units) {
config |= WDT_UNIT_SEC; /* else UNIT is MINUTES */
- printk(KERN_INFO NAME ": timer margin %d seconds\n", units);
+ pr_info("timer margin %d seconds\n", units);
} else {
units /= 60;
- printk(KERN_INFO NAME ": timer margin %d minutes\n", units);
+ pr_info("timer margin %d minutes\n", units);
}
superio_outb(config, WDT_CONFIG);
@@ -165,8 +172,7 @@ it8712f_wdt_update_margin(void)
superio_outb(units, WDT_TIMEOUT);
}
-static int
-it8712f_wdt_get_status(void)
+static int it8712f_wdt_get_status(void)
{
if (superio_inb(WDT_CONTROL) & 0x01)
return WDIOF_CARDRESET;
@@ -174,28 +180,33 @@ it8712f_wdt_get_status(void)
return 0;
}
-static void
-it8712f_wdt_enable(void)
+static int it8712f_wdt_enable(void)
{
- printk(KERN_DEBUG NAME ": enabling watchdog timer\n");
- superio_enter();
+ int ret = superio_enter();
+ if (ret)
+ return ret;
+
+ pr_debug("enabling watchdog timer\n");
superio_select(LDN_GPIO);
- superio_outb(WDT_RESET_GAME, WDT_CONTROL);
+ superio_outb(wdt_control_reg, WDT_CONTROL);
it8712f_wdt_update_margin();
superio_exit();
it8712f_wdt_ping();
+
+ return 0;
}
-static void
-it8712f_wdt_disable(void)
+static int it8712f_wdt_disable(void)
{
- printk(KERN_DEBUG NAME ": disabling watchdog timer\n");
+ int ret = superio_enter();
+ if (ret)
+ return ret;
- superio_enter();
+ pr_debug("disabling watchdog timer\n");
superio_select(LDN_GPIO);
superio_outb(0, WDT_CONFIG);
@@ -205,10 +216,10 @@ it8712f_wdt_disable(void)
superio_outb(0, WDT_TIMEOUT);
superio_exit();
+ return 0;
}
-static int
-it8712f_wdt_notify(struct notifier_block *this,
+static int it8712f_wdt_notify(struct notifier_block *this,
unsigned long code, void *unused)
{
if (code == SYS_HALT || code == SYS_POWER_OFF)
@@ -222,9 +233,8 @@ static struct notifier_block it8712f_wdt_notifier = {
.notifier_call = it8712f_wdt_notify,
};
-static ssize_t
-it8712f_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
+static ssize_t it8712f_wdt_write(struct file *file, const char __user *data,
+ size_t len, loff_t *ppos)
{
/* check for a magic close character */
if (len) {
@@ -235,7 +245,7 @@ it8712f_wdt_write(struct file *file, const char __user *data,
expect_close = 0;
for (i = 0; i < len; ++i) {
char c;
- if (get_user(c, data+i))
+ if (get_user(c, data + i))
return -EFAULT;
if (c == 'V')
expect_close = 42;
@@ -245,28 +255,29 @@ it8712f_wdt_write(struct file *file, const char __user *data,
return len;
}
-static int
-it8712f_wdt_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+static long it8712f_wdt_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
- static struct watchdog_info ident = {
+ static const struct watchdog_info ident = {
.identity = "IT8712F Watchdog",
.firmware_version = 1,
- .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
};
int value;
+ int ret;
switch (cmd) {
- default:
- return -ENOTTY;
case WDIOC_GETSUPPORT:
if (copy_to_user(argp, &ident, sizeof(ident)))
return -EFAULT;
return 0;
case WDIOC_GETSTATUS:
- superio_enter();
+ ret = superio_enter();
+ if (ret)
+ return ret;
superio_select(LDN_GPIO);
value = it8712f_wdt_get_status();
@@ -287,7 +298,9 @@ it8712f_wdt_ioctl(struct inode *inode, struct file *file,
if (value > (max_units * 60))
return -EINVAL;
margin = value;
- superio_enter();
+ ret = superio_enter();
+ if (ret)
+ return ret;
superio_select(LDN_GPIO);
it8712f_wdt_update_margin();
@@ -299,32 +312,34 @@ it8712f_wdt_ioctl(struct inode *inode, struct file *file,
if (put_user(margin, p))
return -EFAULT;
return 0;
+ default:
+ return -ENOTTY;
}
}
-static int
-it8712f_wdt_open(struct inode *inode, struct file *file)
+static int it8712f_wdt_open(struct inode *inode, struct file *file)
{
+ int ret;
/* only allow one at a time */
- if (down_trylock(&it8712f_wdt_sem))
+ if (test_and_set_bit(0, &wdt_open))
return -EBUSY;
- it8712f_wdt_enable();
+ ret = it8712f_wdt_enable();
+ if (ret)
+ return ret;
return nonseekable_open(inode, file);
}
-static int
-it8712f_wdt_release(struct inode *inode, struct file *file)
+static int it8712f_wdt_release(struct inode *inode, struct file *file)
{
if (expect_close != 42) {
- printk(KERN_WARNING NAME
- ": watchdog device closed unexpectedly, will not"
- " disable the watchdog timer\n");
+ pr_warn("watchdog device closed unexpectedly, will not disable the watchdog timer\n");
} else if (!nowayout) {
- it8712f_wdt_disable();
+ if (it8712f_wdt_disable())
+ pr_warn("Watchdog disable failed\n");
}
expect_close = 0;
- up(&it8712f_wdt_sem);
+ clear_bit(0, &wdt_open);
return 0;
}
@@ -333,7 +348,7 @@ static const struct file_operations it8712f_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = it8712f_wdt_write,
- .ioctl = it8712f_wdt_ioctl,
+ .unlocked_ioctl = it8712f_wdt_ioctl,
.open = it8712f_wdt_open,
.release = it8712f_wdt_release,
};
@@ -344,13 +359,14 @@ static struct miscdevice it8712f_wdt_miscdev = {
.fops = &it8712f_wdt_fops,
};
-static int __init
-it8712f_wdt_find(unsigned short *address)
+static int __init it8712f_wdt_find(unsigned short *address)
{
int err = -ENODEV;
int chip_type;
+ int ret = superio_enter();
+ if (ret)
+ return ret;
- superio_enter();
chip_type = superio_inw(DEVID);
if (chip_type != IT8712F_DEVID)
goto exit;
@@ -358,13 +374,13 @@ it8712f_wdt_find(unsigned short *address)
superio_select(LDN_GAME);
superio_outb(1, ACT_REG);
if (!(superio_inb(ACT_REG) & 0x01)) {
- printk(KERN_ERR NAME ": Device not activated, skipping\n");
+ pr_err("Device not activated, skipping\n");
goto exit;
}
*address = superio_inw(BASE_REG);
if (*address == 0) {
- printk(KERN_ERR NAME ": Base address not set, skipping\n");
+ pr_err("Base address not set, skipping\n");
goto exit;
}
@@ -378,8 +394,7 @@ it8712f_wdt_find(unsigned short *address)
if (margin > (max_units * 60))
margin = (max_units * 60);
- printk(KERN_INFO NAME ": Found IT%04xF chip revision %d - "
- "using DogFood address 0x%x\n",
+ pr_info("Found IT%04xF chip revision %d - using DogFood address 0x%x\n",
chip_type, revision, *address);
exit:
@@ -387,36 +402,34 @@ exit:
return err;
}
-static int __init
-it8712f_wdt_init(void)
+static int __init it8712f_wdt_init(void)
{
int err = 0;
- spin_lock_init(&io_lock);
-
if (it8712f_wdt_find(&address))
return -ENODEV;
if (!request_region(address, 1, "IT8712F Watchdog")) {
- printk(KERN_WARNING NAME ": watchdog I/O region busy\n");
+ pr_warn("watchdog I/O region busy\n");
return -EBUSY;
}
- it8712f_wdt_disable();
-
- sema_init(&it8712f_wdt_sem, 1);
+ err = it8712f_wdt_disable();
+ if (err) {
+ pr_err("unable to disable watchdog timer\n");
+ goto out;
+ }
err = register_reboot_notifier(&it8712f_wdt_notifier);
if (err) {
- printk(KERN_ERR NAME ": unable to register reboot notifier\n");
+ pr_err("unable to register reboot notifier\n");
goto out;
}
err = misc_register(&it8712f_wdt_miscdev);
if (err) {
- printk(KERN_ERR NAME
- ": cannot register miscdev on minor=%d (err=%d)\n",
- WATCHDOG_MINOR, err);
+ pr_err("cannot register miscdev on minor=%d (err=%d)\n",
+ WATCHDOG_MINOR, err);
goto reboot_out;
}
@@ -430,8 +443,7 @@ out:
return err;
}
-static void __exit
-it8712f_wdt_exit(void)
+static void __exit it8712f_wdt_exit(void)
{
misc_deregister(&it8712f_wdt_miscdev);
unregister_reboot_notifier(&it8712f_wdt_notifier);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-09 08:00:56 +0000