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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-30 09:59:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-30 09:59:13 -0700
commit19ce0a995ff230b364c7329fd488c70e91c171d9 (patch)
treee24fe57a87d16a54cbffd087fb6af2083f7f2ad0 /drivers/watchdog
parent6bb340c7868fbfd7bd0e8a0e23397a2bcb528429 (diff)
parent4b98b32aefb2c143a40cdaa254eb905f1bb06b5d (diff)
downloadlinux-19ce0a995ff230b364c7329fd488c70e91c171d9.tar.gz
Merge git://www.linux-watchdog.org/linux-watchdog
Pull second set of watchdog updates from Wim Van Sebroeck: "This changeset contains following changes: * Add support for multiple watchdog devices. We use dynamically allocated device id's for this. * Add locking into the generic watchdog infrastructure. * Add support for dynamically allocated watchdog_device structs so that we can deal with devices that get unbound. * convert following drivers to the generic watchdog framework: sch5627, sch5636 and sp805_wdt. * Add DA9052/53 PMIC watchdog support * Fix printk format warnings for iTCO_wdt.c" * git://www.linux-watchdog.org/linux-watchdog: watchdog: iTCO_wdt.c: fix printk format warnings watchdog: sp805_wdt: Add clk_{un}prepare support watchdog: sp805_wdt: convert to watchdog core hwmon/sch56xx: Depend on watchdog for watchdog core functions watchdog: sch56xx-common: set correct bits in register() Watchdog: DA9052/53 PMIC watchdog support watchdog: sch56xx-common: Add proper ref-counting of watchdog data watchdog: sch56xx: Remove unnecessary checks for register changes watchdog: sch56xx: Use watchdog core watchdog: Add support for dynamically allocated watchdog_device structs watchdog: Add Locking support watchdog: watchdog_dev: Rewrite wrapper code watchdog: use dev_ functions watchdog: create all the proper device files watchdog: Add a flag to indicate the watchdog doesn't reboot things watchdog: Add multiple device support watchdog: watchdog_core.h: make functions extern watchdog: correct the name of the watchdog_core inlude file watchdog: Add watchdog_active() routine watchdog: watchdog_dev: include private header to pickup global symbol prototypes
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/Kconfig13
-rw-r--r--drivers/watchdog/Makefile1
-rw-r--r--drivers/watchdog/da9052_wdt.c251
-rw-r--r--drivers/watchdog/iTCO_wdt.c6
-rw-r--r--drivers/watchdog/sp805_wdt.c249
-rw-r--r--drivers/watchdog/via_wdt.c2
-rw-r--r--drivers/watchdog/watchdog_core.c74
-rw-r--r--drivers/watchdog/watchdog_core.h (renamed from drivers/watchdog/watchdog_dev.h)8
-rw-r--r--drivers/watchdog/watchdog_dev.c375
9 files changed, 724 insertions, 255 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index d92d7488be1..fe819b76de5 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -64,6 +64,18 @@ config SOFT_WATCHDOG
To compile this driver as a module, choose M here: the
module will be called softdog.
+config DA9052_WATCHDOG
+ tristate "Dialog DA9052 Watchdog"
+ depends on PMIC_DA9052
+ select WATCHDOG_CORE
+ help
+ Support for the watchdog in the DA9052 PMIC. Watchdog trigger
+ cause system reset.
+
+ Say Y here to include support for the DA9052 watchdog.
+ Alternatively say M to compile the driver as a module,
+ which will be called da9052_wdt.
+
config WM831X_WATCHDOG
tristate "WM831x watchdog"
depends on MFD_WM831X
@@ -87,6 +99,7 @@ config WM8350_WATCHDOG
config ARM_SP805_WATCHDOG
tristate "ARM SP805 Watchdog"
depends on ARM_AMBA
+ select WATCHDOG_CORE
help
ARM Primecell SP805 Watchdog timer. This will reboot your system when
the timeout is reached.
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 442bfbe0882..572b39bed06 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -163,6 +163,7 @@ obj-$(CONFIG_WATCHDOG_CP1XXX) += cpwd.o
obj-$(CONFIG_XEN_WDT) += xen_wdt.o
# Architecture Independent
+obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o
diff --git a/drivers/watchdog/da9052_wdt.c b/drivers/watchdog/da9052_wdt.c
new file mode 100644
index 00000000000..3f75129eb0a
--- /dev/null
+++ b/drivers/watchdog/da9052_wdt.c
@@ -0,0 +1,251 @@
+/*
+ * System monitoring driver for DA9052 PMICs.
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: Anthony Olech <Anthony.Olech@diasemi.com>
+ *
+ * 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/module.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+#include <linux/time.h>
+#include <linux/watchdog.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/delay.h>
+
+#include <linux/mfd/da9052/reg.h>
+#include <linux/mfd/da9052/da9052.h>
+
+#define DA9052_DEF_TIMEOUT 4
+#define DA9052_TWDMIN 256
+
+struct da9052_wdt_data {
+ struct watchdog_device wdt;
+ struct da9052 *da9052;
+ struct kref kref;
+ unsigned long jpast;
+};
+
+static const struct {
+ u8 reg_val;
+ int time; /* Seconds */
+} da9052_wdt_maps[] = {
+ { 1, 2 },
+ { 2, 4 },
+ { 3, 8 },
+ { 4, 16 },
+ { 5, 32 },
+ { 5, 33 }, /* Actual time 32.768s so included both 32s and 33s */
+ { 6, 65 },
+ { 6, 66 }, /* Actual time 65.536s so include both, 65s and 66s */
+ { 7, 131 },
+};
+
+
+static void da9052_wdt_release_resources(struct kref *r)
+{
+ struct da9052_wdt_data *driver_data =
+ container_of(r, struct da9052_wdt_data, kref);
+
+ kfree(driver_data);
+}
+
+static int da9052_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int timeout)
+{
+ struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct da9052 *da9052 = driver_data->da9052;
+ int ret, i;
+
+ /*
+ * Disable the Watchdog timer before setting
+ * new time out.
+ */
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE, 0);
+ if (ret < 0) {
+ dev_err(da9052->dev, "Failed to disable watchdog bit, %d\n",
+ ret);
+ return ret;
+ }
+ if (timeout) {
+ /*
+ * To change the timeout, da9052 needs to
+ * be disabled for at least 150 us.
+ */
+ udelay(150);
+
+ /* Set the desired timeout */
+ for (i = 0; i < ARRAY_SIZE(da9052_wdt_maps); i++)
+ if (da9052_wdt_maps[i].time == timeout)
+ break;
+
+ if (i == ARRAY_SIZE(da9052_wdt_maps))
+ ret = -EINVAL;
+ else
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE,
+ da9052_wdt_maps[i].reg_val);
+ if (ret < 0) {
+ dev_err(da9052->dev,
+ "Failed to update timescale bit, %d\n", ret);
+ return ret;
+ }
+
+ wdt_dev->timeout = timeout;
+ driver_data->jpast = jiffies;
+ }
+
+ return 0;
+}
+
+static void da9052_wdt_ref(struct watchdog_device *wdt_dev)
+{
+ struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+
+ kref_get(&driver_data->kref);
+}
+
+static void da9052_wdt_unref(struct watchdog_device *wdt_dev)
+{
+ struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+
+ kref_put(&driver_data->kref, da9052_wdt_release_resources);
+}
+
+static int da9052_wdt_start(struct watchdog_device *wdt_dev)
+{
+ return da9052_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
+}
+
+static int da9052_wdt_stop(struct watchdog_device *wdt_dev)
+{
+ return da9052_wdt_set_timeout(wdt_dev, 0);
+}
+
+static int da9052_wdt_ping(struct watchdog_device *wdt_dev)
+{
+ struct da9052_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct da9052 *da9052 = driver_data->da9052;
+ unsigned long msec, jnow = jiffies;
+ int ret;
+
+ /*
+ * We have a minimum time for watchdog window called TWDMIN. A write
+ * to the watchdog before this elapsed time should cause an error.
+ */
+ msec = (jnow - driver_data->jpast) * 1000/HZ;
+ if (msec < DA9052_TWDMIN)
+ mdelay(msec);
+
+ /* Reset the watchdog timer */
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_WATCHDOG, 1 << 7);
+ if (ret < 0)
+ goto err_strobe;
+
+ /*
+ * FIXME: Reset the watchdog core, in general PMIC
+ * is supposed to do this
+ */
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_WATCHDOG, 0 << 7);
+err_strobe:
+ return ret;
+}
+
+static struct watchdog_info da9052_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = "DA9052 Watchdog",
+};
+
+static const struct watchdog_ops da9052_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = da9052_wdt_start,
+ .stop = da9052_wdt_stop,
+ .ping = da9052_wdt_ping,
+ .set_timeout = da9052_wdt_set_timeout,
+ .ref = da9052_wdt_ref,
+ .unref = da9052_wdt_unref,
+};
+
+
+static int __devinit da9052_wdt_probe(struct platform_device *pdev)
+{
+ struct da9052 *da9052 = dev_get_drvdata(pdev->dev.parent);
+ struct da9052_wdt_data *driver_data;
+ struct watchdog_device *da9052_wdt;
+ int ret;
+
+ driver_data = devm_kzalloc(&pdev->dev, sizeof(*driver_data),
+ GFP_KERNEL);
+ if (!driver_data) {
+ dev_err(da9052->dev, "Unable to alloacate watchdog device\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+ driver_data->da9052 = da9052;
+
+ da9052_wdt = &driver_data->wdt;
+
+ da9052_wdt->timeout = DA9052_DEF_TIMEOUT;
+ da9052_wdt->info = &da9052_wdt_info;
+ da9052_wdt->ops = &da9052_wdt_ops;
+ watchdog_set_drvdata(da9052_wdt, driver_data);
+
+ kref_init(&driver_data->kref);
+
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to disable watchdog bits, %d\n",
+ ret);
+ goto err;
+ }
+
+ ret = watchdog_register_device(&driver_data->wdt);
+ if (ret != 0) {
+ dev_err(da9052->dev, "watchdog_register_device() failed: %d\n",
+ ret);
+ goto err;
+ }
+
+ dev_set_drvdata(&pdev->dev, driver_data);
+err:
+ return ret;
+}
+
+static int __devexit da9052_wdt_remove(struct platform_device *pdev)
+{
+ struct da9052_wdt_data *driver_data = dev_get_drvdata(&pdev->dev);
+
+ watchdog_unregister_device(&driver_data->wdt);
+ kref_put(&driver_data->kref, da9052_wdt_release_resources);
+
+ return 0;
+}
+
+static struct platform_driver da9052_wdt_driver = {
+ .probe = da9052_wdt_probe,
+ .remove = __devexit_p(da9052_wdt_remove),
+ .driver = {
+ .name = "da9052-watchdog",
+ },
+};
+
+module_platform_driver(da9052_wdt_driver);
+
+MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
+MODULE_DESCRIPTION("DA9052 SM Device Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9052-watchdog");
diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index 741528b032e..bc47e9012f3 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -575,7 +575,7 @@ static int __devinit iTCO_wdt_probe(struct platform_device *dev)
if (!request_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res), dev->name)) {
pr_err("I/O address 0x%04llx already in use, device disabled\n",
- SMI_EN);
+ (u64)SMI_EN);
ret = -EBUSY;
goto unmap_gcs;
}
@@ -592,13 +592,13 @@ static int __devinit iTCO_wdt_probe(struct platform_device *dev)
if (!request_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res), dev->name)) {
pr_err("I/O address 0x%04llx already in use, device disabled\n",
- TCOBASE);
+ (u64)TCOBASE);
ret = -EBUSY;
goto unreg_smi;
}
pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
- ich_info->name, ich_info->iTCO_version, TCOBASE);
+ ich_info->name, ich_info->iTCO_version, (u64)TCOBASE);
/* Clear out the (probably old) status */
outw(0x0008, TCO1_STS); /* Clear the Time Out Status bit */
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
index bbb170e5005..afcd1367654 100644
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -16,20 +16,17 @@
#include <linux/amba/bus.h>
#include <linux/bitops.h>
#include <linux/clk.h>
-#include <linux/fs.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/math64.h>
-#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
-#include <linux/uaccess.h>
#include <linux/watchdog.h>
/* default timeout in seconds */
@@ -56,6 +53,7 @@
/**
* struct sp805_wdt: sp805 wdt device structure
+ * @wdd: instance of struct watchdog_device
* @lock: spin lock protecting dev structure and io access
* @base: base address of wdt
* @clk: clock structure of wdt
@@ -65,24 +63,24 @@
* @timeout: current programmed timeout
*/
struct sp805_wdt {
+ struct watchdog_device wdd;
spinlock_t lock;
void __iomem *base;
struct clk *clk;
struct amba_device *adev;
- unsigned long status;
- #define WDT_BUSY 0
- #define WDT_CAN_BE_CLOSED 1
unsigned int load_val;
unsigned int timeout;
};
-/* local variables */
-static struct sp805_wdt *wdt;
static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout,
+ "Set to 1 to keep watchdog running after device release");
/* This routine finds load value that will reset system in required timout */
-static void wdt_setload(unsigned int timeout)
+static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout)
{
+ struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
u64 load, rate;
rate = clk_get_rate(wdt->clk);
@@ -103,11 +101,14 @@ static void wdt_setload(unsigned int timeout)
/* roundup timeout to closest positive integer value */
wdt->timeout = div_u64((load + 1) * 2 + (rate / 2), rate);
spin_unlock(&wdt->lock);
+
+ return 0;
}
/* returns number of seconds left for reset to occur */
-static u32 wdt_timeleft(void)
+static unsigned int wdt_timeleft(struct watchdog_device *wdd)
{
+ struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
u64 load, rate;
rate = clk_get_rate(wdt->clk);
@@ -123,166 +124,96 @@ static u32 wdt_timeleft(void)
return div_u64(load, rate);
}
-/* enables watchdog timers reset */
-static void wdt_enable(void)
+static int wdt_config(struct watchdog_device *wdd, bool ping)
{
- spin_lock(&wdt->lock);
+ struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
+ int ret;
- writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
- writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
- writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
- writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
- writel_relaxed(LOCK, wdt->base + WDTLOCK);
+ if (!ping) {
+ ret = clk_prepare(wdt->clk);
+ if (ret) {
+ dev_err(&wdt->adev->dev, "clock prepare fail");
+ return ret;
+ }
- /* Flush posted writes. */
- readl_relaxed(wdt->base + WDTLOCK);
- spin_unlock(&wdt->lock);
-}
+ ret = clk_enable(wdt->clk);
+ if (ret) {
+ dev_err(&wdt->adev->dev, "clock enable fail");
+ clk_unprepare(wdt->clk);
+ return ret;
+ }
+ }
-/* disables watchdog timers reset */
-static void wdt_disable(void)
-{
spin_lock(&wdt->lock);
writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
- writel_relaxed(0, wdt->base + WDTCONTROL);
+ writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
+
+ if (!ping) {
+ writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
+ writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
+ WDTCONTROL);
+ }
+
writel_relaxed(LOCK, wdt->base + WDTLOCK);
/* Flush posted writes. */
readl_relaxed(wdt->base + WDTLOCK);
spin_unlock(&wdt->lock);
+
+ return 0;
}
-static ssize_t sp805_wdt_write(struct file *file, const char *data,
- size_t len, loff_t *ppos)
+static int wdt_ping(struct watchdog_device *wdd)
{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- clear_bit(WDT_CAN_BE_CLOSED, &wdt->status);
-
- for (i = 0; i != len; i++) {
- char c;
-
- if (get_user(c, data + i))
- return -EFAULT;
- /* Check for Magic Close character */
- if (c == 'V') {
- set_bit(WDT_CAN_BE_CLOSED,
- &wdt->status);
- break;
- }
- }
- }
- wdt_enable();
- }
- return len;
+ return wdt_config(wdd, true);
}
-static const struct watchdog_info ident = {
- .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
- .identity = MODULE_NAME,
-};
-
-static long sp805_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
+/* enables watchdog timers reset */
+static int wdt_enable(struct watchdog_device *wdd)
{
- int ret = -ENOTTY;
- unsigned int timeout;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- ret = copy_to_user((struct watchdog_info *)arg, &ident,
- sizeof(ident)) ? -EFAULT : 0;
- break;
-
- case WDIOC_GETSTATUS:
- ret = put_user(0, (int *)arg);
- break;
-
- case WDIOC_KEEPALIVE:
- wdt_enable();
- ret = 0;
- break;
-
- case WDIOC_SETTIMEOUT:
- ret = get_user(timeout, (unsigned int *)arg);
- if (ret)
- break;
-
- wdt_setload(timeout);
-
- wdt_enable();
- /* Fall through */
-
- case WDIOC_GETTIMEOUT:
- ret = put_user(wdt->timeout, (unsigned int *)arg);
- break;
- case WDIOC_GETTIMELEFT:
- ret = put_user(wdt_timeleft(), (unsigned int *)arg);
- break;
- }
- return ret;
+ return wdt_config(wdd, false);
}
-static int sp805_wdt_open(struct inode *inode, struct file *file)
+/* disables watchdog timers reset */
+static int wdt_disable(struct watchdog_device *wdd)
{
- int ret = 0;
-
- if (test_and_set_bit(WDT_BUSY, &wdt->status))
- return -EBUSY;
-
- ret = clk_enable(wdt->clk);
- if (ret) {
- dev_err(&wdt->adev->dev, "clock enable fail");
- goto err;
- }
-
- wdt_enable();
+ struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
- /* can not be closed, once enabled */
- clear_bit(WDT_CAN_BE_CLOSED, &wdt->status);
- return nonseekable_open(inode, file);
+ spin_lock(&wdt->lock);
-err:
- clear_bit(WDT_BUSY, &wdt->status);
- return ret;
-}
+ writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
+ writel_relaxed(0, wdt->base + WDTCONTROL);
+ writel_relaxed(LOCK, wdt->base + WDTLOCK);
-static int sp805_wdt_release(struct inode *inode, struct file *file)
-{
- if (!test_bit(WDT_CAN_BE_CLOSED, &wdt->status)) {
- clear_bit(WDT_BUSY, &wdt->status);
- dev_warn(&wdt->adev->dev, "Device closed unexpectedly\n");
- return 0;
- }
+ /* Flush posted writes. */
+ readl_relaxed(wdt->base + WDTLOCK);
+ spin_unlock(&wdt->lock);
- wdt_disable();
clk_disable(wdt->clk);
- clear_bit(WDT_BUSY, &wdt->status);
+ clk_unprepare(wdt->clk);
return 0;
}
-static const struct file_operations sp805_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = sp805_wdt_write,
- .unlocked_ioctl = sp805_wdt_ioctl,
- .open = sp805_wdt_open,
- .release = sp805_wdt_release,
+static const struct watchdog_info wdt_info = {
+ .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = MODULE_NAME,
};
-static struct miscdevice sp805_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &sp805_wdt_fops,
+static const struct watchdog_ops wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = wdt_enable,
+ .stop = wdt_disable,
+ .ping = wdt_ping,
+ .set_timeout = wdt_setload,
+ .get_timeleft = wdt_timeleft,
};
static int __devinit
sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
{
+ struct sp805_wdt *wdt;
int ret = 0;
if (!devm_request_mem_region(&adev->dev, adev->res.start,
@@ -315,19 +246,26 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
}
wdt->adev = adev;
+ wdt->wdd.info = &wdt_info;
+ wdt->wdd.ops = &wdt_ops;
+
spin_lock_init(&wdt->lock);
- wdt_setload(DEFAULT_TIMEOUT);
+ watchdog_set_nowayout(&wdt->wdd, nowayout);
+ watchdog_set_drvdata(&wdt->wdd, wdt);
+ wdt_setload(&wdt->wdd, DEFAULT_TIMEOUT);
- ret = misc_register(&sp805_wdt_miscdev);
- if (ret < 0) {
- dev_warn(&adev->dev, "cannot register misc device\n");
- goto err_misc_register;
+ ret = watchdog_register_device(&wdt->wdd);
+ if (ret) {
+ dev_err(&adev->dev, "watchdog_register_device() failed: %d\n",
+ ret);
+ goto err_register;
}
+ amba_set_drvdata(adev, wdt);
dev_info(&adev->dev, "registration successful\n");
return 0;
-err_misc_register:
+err_register:
clk_put(wdt->clk);
err:
dev_err(&adev->dev, "Probe Failed!!!\n");
@@ -336,7 +274,11 @@ err:
static int __devexit sp805_wdt_remove(struct amba_device *adev)
{
- misc_deregister(&sp805_wdt_miscdev);
+ struct sp805_wdt *wdt = amba_get_drvdata(adev);
+
+ watchdog_unregister_device(&wdt->wdd);
+ amba_set_drvdata(adev, NULL);
+ watchdog_set_drvdata(&wdt->wdd, NULL);
clk_put(wdt->clk);
return 0;
@@ -345,28 +287,22 @@ static int __devexit sp805_wdt_remove(struct amba_device *adev)
#ifdef CONFIG_PM
static int sp805_wdt_suspend(struct device *dev)
{
- if (test_bit(WDT_BUSY, &wdt->status)) {
- wdt_disable();
- clk_disable(wdt->clk);
- }
+ struct sp805_wdt *wdt = dev_get_drvdata(dev);
+
+ if (watchdog_active(&wdt->wdd))
+ return wdt_disable(&wdt->wdd);
return 0;
}
static int sp805_wdt_resume(struct device *dev)
{
- int ret = 0;
+ struct sp805_wdt *wdt = dev_get_drvdata(dev);
- if (test_bit(WDT_BUSY, &wdt->status)) {
- ret = clk_enable(wdt->clk);
- if (ret) {
- dev_err(dev, "clock enable fail");
- return ret;
- }
- wdt_enable();
- }
+ if (watchdog_active(&wdt->wdd))
+ return wdt_enable(&wdt->wdd);
- return ret;
+ return 0;
}
#endif /* CONFIG_PM */
@@ -395,11 +331,6 @@ static struct amba_driver sp805_wdt_driver = {
module_amba_driver(sp805_wdt_driver);
-module_param(nowayout, bool, 0);
-MODULE_PARM_DESC(nowayout,
- "Set to 1 to keep watchdog running after device release");
-
MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>");
MODULE_DESCRIPTION("ARM SP805 Watchdog Driver");
MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
diff --git a/drivers/watchdog/via_wdt.c b/drivers/watchdog/via_wdt.c
index 5603e31afda..aa50da3ccfe 100644
--- a/drivers/watchdog/via_wdt.c
+++ b/drivers/watchdog/via_wdt.c
@@ -91,7 +91,7 @@ static inline void wdt_reset(void)
static void wdt_timer_tick(unsigned long data)
{
if (time_before(jiffies, next_heartbeat) ||
- (!test_bit(WDOG_ACTIVE, &wdt_dev.status))) {
+ (!watchdog_active(&wdt_dev))) {
wdt_reset();
mod_timer(&timer, jiffies + WDT_HEARTBEAT);
} else
diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c
index 14d768bfa26..6aa46a90ff0 100644
--- a/drivers/watchdog/watchdog_core.c
+++ b/drivers/watchdog/watchdog_core.c
@@ -34,8 +34,13 @@
#include <linux/kernel.h> /* For printk/panic/... */
#include <linux/watchdog.h> /* For watchdog specific items */
#include <linux/init.h> /* For __init/__exit/... */
+#include <linux/idr.h> /* For ida_* macros */
+#include <linux/err.h> /* For IS_ERR macros */
-#include "watchdog_dev.h" /* For watchdog_dev_register/... */
+#include "watchdog_core.h" /* For watchdog_dev_register/... */
+
+static DEFINE_IDA(watchdog_ida);
+static struct class *watchdog_class;
/**
* watchdog_register_device() - register a watchdog device
@@ -49,7 +54,7 @@
*/
int watchdog_register_device(struct watchdog_device *wdd)
{
- int ret;
+ int ret, id, devno;
if (wdd == NULL || wdd->info == NULL || wdd->ops == NULL)
return -EINVAL;
@@ -74,10 +79,38 @@ int watchdog_register_device(struct watchdog_device *wdd)
* corrupted in a later stage then we expect a kernel panic!
*/
- /* We only support 1 watchdog device via the /dev/watchdog interface */
+ mutex_init(&wdd->lock);
+ id = ida_simple_get(&watchdog_ida, 0, MAX_DOGS, GFP_KERNEL);
+ if (id < 0)
+ return id;
+ wdd->id = id;
+
ret = watchdog_dev_register(wdd);
if (ret) {
- pr_err("error registering /dev/watchdog (err=%d)\n", ret);
+ ida_simple_remove(&watchdog_ida, id);
+ if (!(id == 0 && ret == -EBUSY))
+ return ret;
+
+ /* Retry in case a legacy watchdog module exists */
+ id = ida_simple_get(&watchdog_ida, 1, MAX_DOGS, GFP_KERNEL);
+ if (id < 0)
+ return id;
+ wdd->id = id;
+
+ ret = watchdog_dev_register(wdd);
+ if (ret) {
+ ida_simple_remove(&watchdog_ida, id);
+ return ret;
+ }
+ }
+
+ devno = wdd->cdev.dev;
+ wdd->dev = device_create(watchdog_class, wdd->parent, devno,
+ NULL, "watchdog%d", wdd->id);
+ if (IS_ERR(wdd->dev)) {
+ watchdog_dev_unregister(wdd);
+ ida_simple_remove(&watchdog_ida, id);
+ ret = PTR_ERR(wdd->dev);
return ret;
}
@@ -95,6 +128,7 @@ EXPORT_SYMBOL_GPL(watchdog_register_device);
void watchdog_unregister_device(struct watchdog_device *wdd)
{
int ret;
+ int devno = wdd->cdev.dev;
if (wdd == NULL)
return;
@@ -102,9 +136,41 @@ void watchdog_unregister_device(struct watchdog_device *wdd)
ret = watchdog_dev_unregister(wdd);
if (ret)
pr_err("error unregistering /dev/watchdog (err=%d)\n", ret);
+ device_destroy(watchdog_class, devno);
+ ida_simple_remove(&watchdog_ida, wdd->id);
+ wdd->dev = NULL;
}
EXPORT_SYMBOL_GPL(watchdog_unregister_device);
+static int __init watchdog_init(void)
+{
+ int err;
+
+ watchdog_class = class_create(THIS_MODULE, "watchdog");
+ if (IS_ERR(watchdog_class)) {
+ pr_err("couldn't create class\n");
+ return PTR_ERR(watchdog_class);
+ }
+
+ err = watchdog_dev_init();
+ if (err < 0) {
+ class_destroy(watchdog_class);
+ return err;
+ }
+
+ return 0;
+}
+
+static void __exit watchdog_exit(void)
+{
+ watchdog_dev_exit();
+ class_destroy(watchdog_class);
+ ida_destroy(&watchdog_ida);
+}
+
+subsys_initcall(watchdog_init);
+module_exit(watchdog_exit);
+
MODULE_AUTHOR("Alan Cox <alan@lxorguk.ukuu.org.uk>");
MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
MODULE_DESCRIPTION("WatchDog Timer Driver Core");
diff --git a/drivers/watchdog/watchdog_dev.h b/drivers/watchdog/watchdog_core.h
index bc7612be25c..6c951418fca 100644
--- a/drivers/watchdog/watchdog_dev.h
+++ b/drivers/watchdog/watchdog_core.h
@@ -26,8 +26,12 @@
* This material is provided "AS-IS" and at no charge.
*/
+#define MAX_DOGS 32 /* Maximum number of watchdog devices */
+
/*
* Functions/procedures to be called by the core
*/
-int watchdog_dev_register(struct watchdog_device *);
-int watchdog_dev_unregister(struct watchdog_device *);
+extern int watchdog_dev_register(struct watchdog_device *);
+extern int watchdog_dev_unregister(struct watchdog_device *);
+extern int __init watchdog_dev_init(void);
+extern void __exit watchdog_dev_exit(void);
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 8558da912c4..672d169bf1d 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -42,10 +42,12 @@
#include <linux/init.h> /* For __init/__exit/... */
#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
-/* make sure we only register one /dev/watchdog device */
-static unsigned long watchdog_dev_busy;
+#include "watchdog_core.h"
+
+/* the dev_t structure to store the dynamically allocated watchdog devices */
+static dev_t watchdog_devt;
/* the watchdog device behind /dev/watchdog */
-static struct watchdog_device *wdd;
+static struct watchdog_device *old_wdd;
/*
* watchdog_ping: ping the watchdog.
@@ -59,13 +61,26 @@ static struct watchdog_device *wdd;
static int watchdog_ping(struct watchdog_device *wddev)
{
- if (test_bit(WDOG_ACTIVE, &wddev->status)) {
- if (wddev->ops->ping)
- return wddev->ops->ping(wddev); /* ping the watchdog */
- else
- return wddev->ops->start(wddev); /* restart watchdog */
+ int err = 0;
+
+ mutex_lock(&wddev->lock);
+
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_ping;
}
- return 0;
+
+ if (!watchdog_active(wddev))
+ goto out_ping;
+
+ if (wddev->ops->ping)
+ err = wddev->ops->ping(wddev); /* ping the watchdog */
+ else
+ err = wddev->ops->start(wddev); /* restart watchdog */
+
+out_ping:
+ mutex_unlock(&wddev->lock);
+ return err;
}
/*
@@ -79,16 +94,25 @@ static int watchdog_ping(struct watchdog_device *wddev)
static int watchdog_start(struct watchdog_device *wddev)
{
- int err;
+ int err = 0;
- if (!test_bit(WDOG_ACTIVE, &wddev->status)) {
- err = wddev->ops->start(wddev);
- if (err < 0)
- return err;
+ mutex_lock(&wddev->lock);
- set_bit(WDOG_ACTIVE, &wddev->status);
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_start;
}
- return 0;
+
+ if (watchdog_active(wddev))
+ goto out_start;
+
+ err = wddev->ops->start(wddev);
+ if (err == 0)
+ set_bit(WDOG_ACTIVE, &wddev->status);
+
+out_start:
+ mutex_unlock(&wddev->lock);
+ return err;
}
/*
@@ -103,22 +127,155 @@ static int watchdog_start(struct watchdog_device *wddev)
static int watchdog_stop(struct watchdog_device *wddev)
{
- int err = -EBUSY;
+ int err = 0;
- if (test_bit(WDOG_NO_WAY_OUT, &wddev->status)) {
- pr_info("%s: nowayout prevents watchdog to be stopped!\n",
- wddev->info->identity);
- return err;
+ mutex_lock(&wddev->lock);
+
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_stop;
}
- if (test_bit(WDOG_ACTIVE, &wddev->status)) {
- err = wddev->ops->stop(wddev);
- if (err < 0)
- return err;
+ if (!watchdog_active(wddev))
+ goto out_stop;
+ if (test_bit(WDOG_NO_WAY_OUT, &wddev->status)) {
+ dev_info(wddev->dev, "nowayout prevents watchdog being stopped!\n");
+ err = -EBUSY;
+ goto out_stop;
+ }
+
+ err = wddev->ops->stop(wddev);
+ if (err == 0)
clear_bit(WDOG_ACTIVE, &wddev->status);
+
+out_stop:
+ mutex_unlock(&wddev->lock);
+ return err;
+}
+
+/*
+ * watchdog_get_status: wrapper to get the watchdog status
+ * @wddev: the watchdog device to get the status from
+ * @status: the status of the watchdog device
+ *
+ * Get the watchdog's status flags.
+ */
+
+static int watchdog_get_status(struct watchdog_device *wddev,
+ unsigned int *status)
+{
+ int err = 0;
+
+ *status = 0;
+ if (!wddev->ops->status)
+ return -EOPNOTSUPP;
+
+ mutex_lock(&wddev->lock);
+
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_status;
}
- return 0;
+
+ *status = wddev->ops->status(wddev);
+
+out_status:
+ mutex_unlock(&wddev->lock);
+ return err;
+}
+
+/*
+ * watchdog_set_timeout: set the watchdog timer timeout
+ * @wddev: the watchdog device to set the timeout for
+ * @timeout: timeout to set in seconds
+ */
+
+static int watchdog_set_timeout(struct watchdog_device *wddev,
+ unsigned int timeout)
+{
+ int err;
+
+ if ((wddev->ops->set_timeout == NULL) ||
+ !(wddev->info->options & WDIOF_SETTIMEOUT))
+ return -EOPNOTSUPP;
+
+ if ((wddev->max_timeout != 0) &&
+ (timeout < wddev->min_timeout || timeout > wddev->max_timeout))
+ return -EINVAL;
+
+ mutex_lock(&wddev->lock);
+
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_timeout;
+ }
+
+ err = wddev->ops->set_timeout(wddev, timeout);
+
+out_timeout:
+ mutex_unlock(&wddev->lock);
+ return err;
+}
+
+/*
+ * watchdog_get_timeleft: wrapper to get the time left before a reboot
+ * @wddev: the watchdog device to get the remaining time from
+ * @timeleft: the time that's left
+ *
+ * Get the time before a watchdog will reboot (if not pinged).
+ */
+
+static int watchdog_get_timeleft(struct watchdog_device *wddev,
+ unsigned int *timeleft)
+{
+ int err = 0;
+
+ *timeleft = 0;
+ if (!wddev->ops->get_timeleft)
+ return -EOPNOTSUPP;
+
+ mutex_lock(&wddev->lock);
+
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_timeleft;
+ }
+
+ *timeleft = wddev->ops->get_timeleft(wddev);
+
+out_timeleft:
+ mutex_unlock(&wddev->lock);
+ return err;
+}
+
+/*
+ * watchdog_ioctl_op: call the watchdog drivers ioctl op if defined
+ * @wddev: the watchdog device to do the ioctl on
+ * @cmd: watchdog command
+ * @arg: argument pointer
+ */
+
+static int watchdog_ioctl_op(struct watchdog_device *wddev, unsigned int cmd,
+ unsigned long arg)
+{
+ int err;
+
+ if (!wddev->ops->ioctl)
+ return -ENOIOCTLCMD;
+
+ mutex_lock(&wddev->lock);
+
+ if (test_bit(WDOG_UNREGISTERED, &wddev->status)) {
+ err = -ENODEV;
+ goto out_ioctl;
+ }
+
+ err = wddev->ops->ioctl(wddev, cmd, arg);
+
+out_ioctl:
+ mutex_unlock(&wddev->lock);
+ return err;
}
/*
@@ -136,6 +293,7 @@ static int watchdog_stop(struct watchdog_device *wddev)
static ssize_t watchdog_write(struct file *file, const char __user *data,
size_t len, loff_t *ppos)
{
+ struct watchdog_device *wdd = file->private_data;
size_t i;
char c;
@@ -175,23 +333,24 @@ static ssize_t watchdog_write(struct file *file, const char __user *data,
static long watchdog_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
+ struct watchdog_device *wdd = file->private_data;
void __user *argp = (void __user *)arg;
int __user *p = argp;
unsigned int val;
int err;
- if (wdd->ops->ioctl) {
- err = wdd->ops->ioctl(wdd, cmd, arg);
- if (err != -ENOIOCTLCMD)
- return err;
- }
+ err = watchdog_ioctl_op(wdd, cmd, arg);
+ if (err != -ENOIOCTLCMD)
+ return err;
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, wdd->info,
sizeof(struct watchdog_info)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
- val = wdd->ops->status ? wdd->ops->status(wdd) : 0;
+ err = watchdog_get_status(wdd, &val);
+ if (err)
+ return err;
return put_user(val, p);
case WDIOC_GETBOOTSTATUS:
return put_user(wdd->bootstatus, p);
@@ -215,15 +374,9 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
watchdog_ping(wdd);
return 0;
case WDIOC_SETTIMEOUT:
- if ((wdd->ops->set_timeout == NULL) ||
- !(wdd->info->options & WDIOF_SETTIMEOUT))
- return -EOPNOTSUPP;
if (get_user(val, p))
return -EFAULT;
- if ((wdd->max_timeout != 0) &&
- (val < wdd->min_timeout || val > wdd->max_timeout))
- return -EINVAL;
- err = wdd->ops->set_timeout(wdd, val);
+ err = watchdog_set_timeout(wdd, val);
if (err < 0)
return err;
/* If the watchdog is active then we send a keepalive ping
@@ -237,21 +390,21 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
return -EOPNOTSUPP;
return put_user(wdd->timeout, p);
case WDIOC_GETTIMELEFT:
- if (!wdd->ops->get_timeleft)
- return -EOPNOTSUPP;
-
- return put_user(wdd->ops->get_timeleft(wdd), p);
+ err = watchdog_get_timeleft(wdd, &val);
+ if (err)
+ return err;
+ return put_user(val, p);
default:
return -ENOTTY;
}
}
/*
- * watchdog_open: open the /dev/watchdog device.
+ * watchdog_open: open the /dev/watchdog* devices.
* @inode: inode of device
* @file: file handle to device
*
- * When the /dev/watchdog device gets opened, we start the watchdog.
+ * When the /dev/watchdog* device gets opened, we start the watchdog.
* Watch out: the /dev/watchdog device is single open, so we make sure
* it can only be opened once.
*/
@@ -259,6 +412,13 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
static int watchdog_open(struct inode *inode, struct file *file)
{
int err = -EBUSY;
+ struct watchdog_device *wdd;
+
+ /* Get the corresponding watchdog device */
+ if (imajor(inode) == MISC_MAJOR)
+ wdd = old_wdd;
+ else
+ wdd = container_of(inode->i_cdev, struct watchdog_device, cdev);
/* the watchdog is single open! */
if (test_and_set_bit(WDOG_DEV_OPEN, &wdd->status))
@@ -275,6 +435,11 @@ static int watchdog_open(struct inode *inode, struct file *file)
if (err < 0)
goto out_mod;
+ file->private_data = wdd;
+
+ if (wdd->ops->ref)
+ wdd->ops->ref(wdd);
+
/* dev/watchdog is a virtual (and thus non-seekable) filesystem */
return nonseekable_open(inode, file);
@@ -286,9 +451,9 @@ out:
}
/*
- * watchdog_release: release the /dev/watchdog device.
- * @inode: inode of device
- * @file: file handle to device
+ * watchdog_release: release the watchdog device.
+ * @inode: inode of device
+ * @file: file handle to device
*
* This is the code for when /dev/watchdog gets closed. We will only
* stop the watchdog when we have received the magic char (and nowayout
@@ -297,6 +462,7 @@ out:
static int watchdog_release(struct inode *inode, struct file *file)
{
+ struct watchdog_device *wdd = file->private_data;
int err = -EBUSY;
/*
@@ -310,7 +476,10 @@ static int watchdog_release(struct inode *inode, struct file *file)
/* If the watchdog was not stopped, send a keepalive ping */
if (err < 0) {
- pr_crit("%s: watchdog did not stop!\n", wdd->info->identity);
+ mutex_lock(&wdd->lock);
+ if (!test_bit(WDOG_UNREGISTERED, &wdd->status))
+ dev_crit(wdd->dev, "watchdog did not stop!\n");
+ mutex_unlock(&wdd->lock);
watchdog_ping(wdd);
}
@@ -320,6 +489,10 @@ static int watchdog_release(struct inode *inode, struct file *file)
/* make sure that /dev/watchdog can be re-opened */
clear_bit(WDOG_DEV_OPEN, &wdd->status);
+ /* Note wdd may be gone after this, do not use after this! */
+ if (wdd->ops->unref)
+ wdd->ops->unref(wdd);
+
return 0;
}
@@ -338,62 +511,92 @@ static struct miscdevice watchdog_miscdev = {
};
/*
- * watchdog_dev_register:
+ * watchdog_dev_register: register a watchdog device
* @watchdog: watchdog device
*
- * Register a watchdog device as /dev/watchdog. /dev/watchdog
- * is actually a miscdevice and thus we set it up like that.
+ * Register a watchdog device including handling the legacy
+ * /dev/watchdog node. /dev/watchdog is actually a miscdevice and
+ * thus we set it up like that.
*/
int watchdog_dev_register(struct watchdog_device *watchdog)
{
- int err;
-
- /* Only one device can register for /dev/watchdog */
- if (test_and_set_bit(0, &watchdog_dev_busy)) {
- pr_err("only one watchdog can use /dev/watchdog\n");
- return -EBUSY;
+ int err, devno;
+
+ if (watchdog->id == 0) {
+ watchdog_miscdev.parent = watchdog->parent;
+ err = misc_register(&watchdog_miscdev);
+ if (err != 0) {
+ pr_err("%s: cannot register miscdev on minor=%d (err=%d).\n",
+ watchdog->info->identity, WATCHDOG_MINOR, err);
+ if (err == -EBUSY)
+ pr_err("%s: a legacy watchdog module is probably present.\n",
+ watchdog->info->identity);
+ return err;
+ }
+ old_wdd = watchdog;
}
- wdd = watchdog;
-
- err = misc_register(&watchdog_miscdev);
- if (err != 0) {
- pr_err("%s: cannot register miscdev on minor=%d (err=%d)\n",
- watchdog->info->identity, WATCHDOG_MINOR, err);
- goto out;
+ /* Fill in the data structures */
+ devno = MKDEV(MAJOR(watchdog_devt), watchdog->id);
+ cdev_init(&watchdog->cdev, &watchdog_fops);
+ watchdog->cdev.owner = watchdog->ops->owner;
+
+ /* Add the device */
+ err = cdev_add(&watchdog->cdev, devno, 1);
+ if (err) {
+ pr_err("watchdog%d unable to add device %d:%d\n",
+ watchdog->id, MAJOR(watchdog_devt), watchdog->id);
+ if (watchdog->id == 0) {
+ misc_deregister(&watchdog_miscdev);
+ old_wdd = NULL;
+ }
}
-
- return 0;
-
-out:
- wdd = NULL;
- clear_bit(0, &watchdog_dev_busy);
return err;
}
/*
- * watchdog_dev_unregister:
+ * watchdog_dev_unregister: unregister a watchdog device
* @watchdog: watchdog device
*
- * Deregister the /dev/watchdog device.
+ * Unregister the watchdog and if needed the legacy /dev/watchdog device.
*/
int watchdog_dev_unregister(struct watchdog_device *watchdog)
{
- /* Check that a watchdog device was registered in the past */
- if (!test_bit(0, &watchdog_dev_busy) || !wdd)
- return -ENODEV;
-
- /* We can only unregister the watchdog device that was registered */
- if (watchdog != wdd) {
- pr_err("%s: watchdog was not registered as /dev/watchdog\n",
- watchdog->info->identity);
- return -ENODEV;
+ mutex_lock(&watchdog->lock);
+ set_bit(WDOG_UNREGISTERED, &watchdog->status);
+ mutex_unlock(&watchdog->lock);
+
+ cdev_del(&watchdog->cdev);
+ if (watchdog->id == 0) {
+ misc_deregister(&watchdog_miscdev);
+ old_wdd = NULL;
}
-
- misc_deregister(&watchdog_miscdev);
- wdd = NULL;
- clear_bit(0, &watchdog_dev_busy);
return 0;
}
+
+/*
+ * watchdog_dev_init: init dev part of watchdog core
+ *
+ * Allocate a range of chardev nodes to use for watchdog devices
+ */
+
+int __init watchdog_dev_init(void)
+{
+ int err = alloc_chrdev_region(&watchdog_devt, 0, MAX_DOGS, "watchdog");
+ if (err < 0)
+ pr_err("watchdog: unable to allocate char dev region\n");
+ return err;
+}
+
+/*
+ * watchdog_dev_exit: exit dev part of watchdog core
+ *
+ * Release the range of chardev nodes used for watchdog devices
+ */
+
+void __exit watchdog_dev_exit(void)
+{
+ unregister_chrdev_region(watchdog_devt, MAX_DOGS);
+}