Merge git://www.linux-watchdog.org/linux-watchdog

Pull watchdog updates from Wim Van Sebroeck:
 "This contains:

   - new driver for ST's LPC Watchdog
   - new driver for Conexant Digicolor CX92755 SoC
   - new driver for DA9062 watchdog
   - Addition of the watchdog registration deferral mechanism
   - several improvements on omap_wdt
   - several improvements and reboot-support for imgpdc_wdt
   - max63xx_wdt improvements
   - imx2_wdt improvements
   - dw_wdt improvements
   - and other small improvements and fixes"

* git://www.linux-watchdog.org/linux-watchdog: (37 commits)
  watchdog: omap_wdt: early_enable module parameter
  watchdog: gpio_wdt: Add option for early registration
  watchdog: watchdog_core: Add watchdog registration deferral mechanism
  watchdog: max63xx: dynamically allocate device
  watchdog: imx2_wdt: Disable previously acquired clock on error path
  watchdog: imx2_wdt: Check for clk_prepare_enable() error
  watchdog: hpwdt: Add support for WDIOC_SETOPTIONS
  watchdog: docs: omap_wdt also understands nowayout
  watchdog: omap_wdt: implement get_timeleft
  watchdog: da9062: DA9062 watchdog driver
  watchdog: imx2_wdt: set watchdog parent device
  watchdog: mena21_wdt: Fix possible NULL pointer dereference
  watchdog: dw_wdt: keepalive the watchdog at write time
  watchdog: dw_wdt: No need for a spinlock
  watchdog: imx2_wdt: also set wdog->timeout to new_timeout
  watchdog: Allow compile test of GPIO consumers if !GPIOLIB
  watchdog: cadence: Add dependency on HAS_IOMEM
  watchdog: max63xx_wdt: Constify platform_device_id
  watchdog: MAX63XX_WATCHDOG does not depend on ARM
  watchdog: imgpdc: Add some documentation about the timeout
  ...

21 files changed, 913 insertions, 159 deletions

diff --git a/Documentation/devicetree/bindings/watchdog/digicolor-wdt.txt b/Documentation/devicetree/bindings/watchdog/digicolor-wdt.txt
new file mode 100644
index 000000000000..a882967e17d4
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/digicolor-wdt.txt
@@ -0,0 +1,25 @@
+Conexant Digicolor SoCs Watchdog timer
+
+The watchdog functionality in Conexant Digicolor SoCs relies on the so called
+"Agent Communication" block. This block includes the eight programmable system
+timer counters. The first timer (called "Timer A") is the only one that can be
+used as watchdog.
+
+Required properties:
+
+- compatible : Should be "cnxt,cx92755-wdt"
+- reg : Specifies base physical address and size of the registers
+- clocks : phandle; specifies the clock that drives the timer
+
+Optional properties:
+
+- timeout-sec : Contains the watchdog timeout in seconds
+
+Example:
+
+	watchdog@f0000fc0 {
+		compatible = "cnxt,cx92755-wdt";
+		reg = <0xf0000fc0 0x8>;
+		clocks = <&main_clk>;
+		timeout-sec = <15>;
+	};
diff --git a/Documentation/devicetree/bindings/watchdog/omap-wdt.txt b/Documentation/devicetree/bindings/watchdog/omap-wdt.txt
index c227970671ea..1fa20e453a2d 100644
--- a/Documentation/devicetree/bindings/watchdog/omap-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/omap-wdt.txt
@@ -1,10 +1,11 @@
 TI Watchdog Timer (WDT) Controller for OMAP
 
 Required properties:
-compatible:
-- "ti,omap3-wdt" for OMAP3
-- "ti,omap4-wdt" for OMAP4
-- ti,hwmods: Name of the hwmod associated to the WDT
+- compatible : "ti,omap3-wdt" for OMAP3 or "ti,omap4-wdt" for OMAP4
+- ti,hwmods : Name of the hwmod associated to the WDT
+
+Optional properties:
+- timeout-sec : default watchdog timeout in seconds
 
 Examples:
 
diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt
index a0438f3957ca..d8b0d3367706 100644
--- a/Documentation/watchdog/watchdog-kernel-api.txt
+++ b/Documentation/watchdog/watchdog-kernel-api.txt
@@ -36,6 +36,10 @@ The watchdog_unregister_device routine deregisters a registered watchdog timer
 device. The parameter of this routine is the pointer to the registered
 watchdog_device structure.
 
+The watchdog subsystem includes an registration deferral mechanism,
+which allows you to register an watchdog as early as you wish during
+the boot process.
+
 The watchdog device structure looks like this:
 
 struct watchdog_device {
@@ -52,6 +56,7 @@ struct watchdog_device {
 	void *driver_data;
 	struct mutex lock;
 	unsigned long status;
+	struct list_head deferred;
 };
 
 It contains following fields:
@@ -80,6 +85,8 @@ It contains following fields:
   information about the status of the device (Like: is the watchdog timer
   running/active, is the nowayout bit set, is the device opened via
   the /dev/watchdog interface or not, ...).
+* deferred: entry in wtd_deferred_reg_list which is used to
+  register early initialized watchdogs.
 
 The list of watchdog operations is defined as:
 
diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt
index 692791cc674c..9f9ec9f76039 100644
--- a/Documentation/watchdog/watchdog-parameters.txt
+++ b/Documentation/watchdog/watchdog-parameters.txt
@@ -208,6 +208,9 @@ nowayout: Watchdog cannot be stopped once started
 -------------------------------------------------
 omap_wdt:
 timer_margin: initial watchdog timeout (in seconds)
+early_enable: Watchdog is started on module insertion (default=0
+nowayout: Watchdog cannot be stopped once started
+	(default=kernel config parameter)
 -------------------------------------------------
 orion_wdt:
 heartbeat: Initial watchdog heartbeat in seconds
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 262647bbc614..241fafde42cb 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1,3 +1,4 @@
+
 #
 # Watchdog device configuration
 #
@@ -96,6 +97,15 @@ config DA9063_WATCHDOG
 
 	  This driver can be built as a module. The module name is da9063_wdt.
 
+config DA9062_WATCHDOG
+	tristate "Dialog DA9062 Watchdog"
+	depends on MFD_DA9062
+	select WATCHDOG_CORE
+	help
+	  Support for the watchdog in the DA9062 PMIC.
+
+	  This driver can be built as a module. The module name is da9062_wdt.
+
 config GPIO_WATCHDOG
 	tristate "Watchdog device controlled through GPIO-line"
 	depends on OF_GPIO
@@ -104,6 +114,17 @@ config GPIO_WATCHDOG
 	  If you say yes here you get support for watchdog device
 	  controlled through GPIO-line.
 
+config GPIO_WATCHDOG_ARCH_INITCALL
+	bool "Register the watchdog as early as possible"
+	depends on GPIO_WATCHDOG=y
+	help
+	  In some situations, the default initcall level (module_init)
+	  in not early enough in the boot process to avoid the watchdog
+	  to be triggered.
+	  If you say yes here, the initcall level would be raised to
+	  arch_initcall.
+	  If in doubt, say N.
+
 config MENF21BMC_WATCHDOG
 	tristate "MEN 14F021P00 BMC Watchdog"
 	depends on MFD_MENF21BMC
@@ -169,6 +190,7 @@ config AT91SAM9X_WATCHDOG
 
 config CADENCE_WATCHDOG
 	tristate "Cadence Watchdog Timer"
+	depends on HAS_IOMEM
 	select WATCHDOG_CORE
 	help
 	  Say Y here if you want to include support for the watchdog
@@ -408,7 +430,7 @@ config TS72XX_WATCHDOG
 
 config MAX63XX_WATCHDOG
 	tristate "Max63xx watchdog"
-	depends on ARM && HAS_IOMEM
+	depends on HAS_IOMEM
 	select WATCHDOG_CORE
 	help
 	  Support for memory mapped max63{69,70,71,72,73,74} watchdog timer.
@@ -526,6 +548,16 @@ config MEDIATEK_WATCHDOG
 	  To compile this driver as a module, choose M here: the
 	  module will be called mtk_wdt.
 
+config DIGICOLOR_WATCHDOG
+	tristate "Conexant Digicolor SoCs watchdog support"
+	depends on ARCH_DIGICOLOR
+	select WATCHDOG_CORE
+	help
+	  Say Y here to include support for the watchdog timer
+	  in Conexant Digicolor SoCs.
+	  To compile this driver as a module, choose M here: the
+	  module will be called digicolor_wdt.
+
 # AVR32 Architecture
 
 config AT32AP700X_WDT
@@ -1355,7 +1387,7 @@ config BOOKE_WDT_DEFAULT_TIMEOUT
 config MEN_A21_WDT
        tristate "MEN A21 VME CPU Carrier Board Watchdog Timer"
        select WATCHDOG_CORE
-       depends on GPIOLIB
+       depends on GPIOLIB || COMPILE_TEST
        help
         Watchdog driver for MEN A21 VMEbus CPU Carrier Boards.
 
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index d98768c7d928..59ea9a1b8e76 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -65,6 +65,7 @@ obj-$(CONFIG_BCM_KONA_WDT) += bcm_kona_wdt.o
 obj-$(CONFIG_TEGRA_WATCHDOG) += tegra_wdt.o
 obj-$(CONFIG_MESON_WATCHDOG) += meson_wdt.o
 obj-$(CONFIG_MEDIATEK_WATCHDOG) += mtk_wdt.o
+obj-$(CONFIG_DIGICOLOR_WATCHDOG) += digicolor_wdt.o
 
 # AVR32 Architecture
 obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
@@ -180,6 +181,7 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
 # Architecture Independent
 obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
 obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
+obj-$(CONFIG_DA9062_WATCHDOG) += da9062_wdt.o
 obj-$(CONFIG_DA9063_WATCHDOG) += da9063_wdt.o
 obj-$(CONFIG_GPIO_WATCHDOG)	+= gpio_wdt.o
 obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
index 1443b3c391de..e4698f7c5f93 100644
--- a/drivers/watchdog/at91sam9_wdt.c
+++ b/drivers/watchdog/at91sam9_wdt.c
@@ -40,9 +40,9 @@
 #define DRV_NAME "AT91SAM9 Watchdog"
 
 #define wdt_read(wdt, field) \
-	__raw_readl((wdt)->base + (field))
+	readl_relaxed((wdt)->base + (field))
 #define wdt_write(wtd, field, val) \
-	__raw_writel((val), (wdt)->base + (field))
+	writel_relaxed((val), (wdt)->base + (field))
 
 /* AT91SAM9 watchdog runs a 12bit counter @ 256Hz,
  * use this to convert a watchdog
diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c
new file mode 100644
index 000000000000..b3a870ce85be
--- /dev/null
+++ b/drivers/watchdog/da9062_wdt.c
@@ -0,0 +1,253 @@
+/*
+ * da9062_wdt.c - WDT device driver for DA9062
+ * Copyright (C) 2015  Dialog Semiconductor 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/jiffies.h>
+#include <linux/mfd/da9062/registers.h>
+#include <linux/mfd/da9062/core.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+
+static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
+#define DA9062_TWDSCALE_DISABLE		0
+#define DA9062_TWDSCALE_MIN		1
+#define DA9062_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
+#define DA9062_WDT_MIN_TIMEOUT		wdt_timeout[DA9062_TWDSCALE_MIN]
+#define DA9062_WDT_MAX_TIMEOUT		wdt_timeout[DA9062_TWDSCALE_MAX]
+#define DA9062_WDG_DEFAULT_TIMEOUT	wdt_timeout[DA9062_TWDSCALE_MAX-1]
+#define DA9062_RESET_PROTECTION_MS	300
+
+struct da9062_watchdog {
+	struct da9062 *hw;
+	struct watchdog_device wdtdev;
+	unsigned long j_time_stamp;
+};
+
+static void da9062_set_window_start(struct da9062_watchdog *wdt)
+{
+	wdt->j_time_stamp = jiffies;
+}
+
+static void da9062_apply_window_protection(struct da9062_watchdog *wdt)
+{
+	unsigned long delay = msecs_to_jiffies(DA9062_RESET_PROTECTION_MS);
+	unsigned long timeout = wdt->j_time_stamp + delay;
+	unsigned long now = jiffies;
+	unsigned int diff_ms;
+
+	/* if time-limit has not elapsed then wait for remainder */
+	if (time_before(now, timeout)) {
+		diff_ms = jiffies_to_msecs(timeout-now);
+		dev_dbg(wdt->hw->dev,
+			"Kicked too quickly. Delaying %u msecs\n", diff_ms);
+		msleep(diff_ms);
+	}
+}
+
+static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
+{
+	unsigned int i;
+
+	for (i = DA9062_TWDSCALE_MIN; i <= DA9062_TWDSCALE_MAX; i++) {
+		if (wdt_timeout[i] >= secs)
+			return i;
+	}
+
+	return DA9062_TWDSCALE_MAX;
+}
+
+static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt)
+{
+	int ret;
+
+	da9062_apply_window_protection(wdt);
+
+	ret = regmap_update_bits(wdt->hw->regmap,
+			   DA9062AA_CONTROL_F,
+			   DA9062AA_WATCHDOG_MASK,
+			   DA9062AA_WATCHDOG_MASK);
+
+	da9062_set_window_start(wdt);
+
+	return ret;
+}
+
+static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt,
+					      unsigned int regval)
+{
+	struct da9062 *chip = wdt->hw;
+	int ret;
+
+	ret = da9062_reset_watchdog_timer(wdt);
+	if (ret)
+		return ret;
+
+	return regmap_update_bits(chip->regmap,
+				  DA9062AA_CONTROL_D,
+				  DA9062AA_TWDSCALE_MASK,
+				  regval);
+}
+
+static int da9062_wdt_start(struct watchdog_device *wdd)
+{
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+	unsigned int selector;
+	int ret;
+
+	selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
+	ret = da9062_wdt_update_timeout_register(wdt, selector);
+	if (ret)
+		dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n",
+			ret);
+
+	return ret;
+}
+
+static int da9062_wdt_stop(struct watchdog_device *wdd)
+{
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+	int ret;
+
+	ret = da9062_reset_watchdog_timer(wdt);
+	if (ret) {
+		dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
+			ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(wdt->hw->regmap,
+				 DA9062AA_CONTROL_D,
+				 DA9062AA_TWDSCALE_MASK,
+				 DA9062_TWDSCALE_DISABLE);
+	if (ret)
+		dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n",
+			ret);
+
+	return ret;
+}
+
+static int da9062_wdt_ping(struct watchdog_device *wdd)
+{
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+	int ret;
+
+	ret = da9062_reset_watchdog_timer(wdt);
+	if (ret)
+		dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
+			ret);
+
+	return ret;
+}
+
+static int da9062_wdt_set_timeout(struct watchdog_device *wdd,
+				  unsigned int timeout)
+{
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+	unsigned int selector;
+	int ret;
+
+	selector = da9062_wdt_timeout_to_sel(timeout);
+	ret = da9062_wdt_update_timeout_register(wdt, selector);
+	if (ret)
+		dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n",
+			ret);
+	else
+		wdd->timeout = wdt_timeout[selector];
+
+	return ret;
+}
+
+static const struct watchdog_info da9062_watchdog_info = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+	.identity = "DA9062 WDT",
+};
+
+static const struct watchdog_ops da9062_watchdog_ops = {
+	.owner = THIS_MODULE,
+	.start = da9062_wdt_start,
+	.stop = da9062_wdt_stop,
+	.ping = da9062_wdt_ping,
+	.set_timeout = da9062_wdt_set_timeout,
+};
+
+static int da9062_wdt_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct da9062 *chip;
+	struct da9062_watchdog *wdt;
+
+	chip = dev_get_drvdata(pdev->dev.parent);
+	if (!chip)
+		return -EINVAL;
+
+	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	wdt->hw = chip;
+
+	wdt->wdtdev.info = &da9062_watchdog_info;
+	wdt->wdtdev.ops = &da9062_watchdog_ops;
+	wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT;
+	wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT;
+	wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
+	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
+
+	watchdog_set_drvdata(&wdt->wdtdev, wdt);
+	dev_set_drvdata(&pdev->dev, wdt);
+
+	ret = watchdog_register_device(&wdt->wdtdev);
+	if (ret < 0) {
+		dev_err(wdt->hw->dev,
+			"watchdog registration failed (%d)\n", ret);
+		return ret;
+	}
+
+	da9062_set_window_start(wdt);
+
+	ret = da9062_wdt_ping(&wdt->wdtdev);
+	if (ret < 0)
+		watchdog_unregister_device(&wdt->wdtdev);
+
+	return ret;
+}
+
+static int da9062_wdt_remove(struct platform_device *pdev)
+{
+	struct da9062_watchdog *wdt = dev_get_drvdata(&pdev->dev);
+
+	watchdog_unregister_device(&wdt->wdtdev);
+	return 0;
+}
+
+static struct platform_driver da9062_wdt_driver = {
+	.probe = da9062_wdt_probe,
+	.remove = da9062_wdt_remove,
+	.driver = {
+		.name = "da9062-watchdog",
+	},
+};
+module_platform_driver(da9062_wdt_driver);
+
+MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
+MODULE_DESCRIPTION("WDT device driver for Dialog DA9062");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9062-watchdog");
diff --git a/drivers/watchdog/digicolor_wdt.c b/drivers/watchdog/digicolor_wdt.c
new file mode 100644
index 000000000000..31d8e4936611
--- /dev/null
+++ b/drivers/watchdog/digicolor_wdt.c
@@ -0,0 +1,205 @@
+/*
+ * Watchdog driver for Conexant Digicolor
+ *
+ * Copyright (C) 2015 Paradox Innovation 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/types.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/watchdog.h>
+#include <linux/reboot.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+
+#define TIMER_A_CONTROL		0
+#define TIMER_A_COUNT		4
+
+#define TIMER_A_ENABLE_COUNT	BIT(0)
+#define TIMER_A_ENABLE_WATCHDOG	BIT(1)
+
+struct dc_wdt {
+	void __iomem		*base;
+	struct clk		*clk;
+	struct notifier_block	restart_handler;
+	spinlock_t		lock;
+};
+
+static unsigned timeout;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
+
+static void dc_wdt_set(struct dc_wdt *wdt, u32 ticks)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&wdt->lock, flags);
+
+	writel_relaxed(0, wdt->base + TIMER_A_CONTROL);
+	writel_relaxed(ticks, wdt->base + TIMER_A_COUNT);
+	writel_relaxed(TIMER_A_ENABLE_COUNT | TIMER_A_ENABLE_WATCHDOG,
+		       wdt->base + TIMER_A_CONTROL);
+
+	spin_unlock_irqrestore(&wdt->lock, flags);
+}
+
+static int dc_restart_handler(struct notifier_block *this, unsigned long mode,
+			      void *cmd)
+{
+	struct dc_wdt *wdt = container_of(this, struct dc_wdt, restart_handler);
+
+	dc_wdt_set(wdt, 1);
+	/* wait for reset to assert... */
+	mdelay(500);
+
+	return NOTIFY_DONE;
+}
+
+static int dc_wdt_start(struct watchdog_device *wdog)
+{
+	struct dc_wdt *wdt = watchdog_get_drvdata(wdog);
+
+	dc_wdt_set(wdt, wdog->timeout * clk_get_rate(wdt->clk));
+
+	return 0;
+}
+
+static int dc_wdt_stop(struct watchdog_device *wdog)
+{
+	struct dc_wdt *wdt = watchdog_get_drvdata(wdog);
+
+	writel_relaxed(0, wdt->base + TIMER_A_CONTROL);
+
+	return 0;
+}
+
+static int dc_wdt_set_timeout(struct watchdog_device *wdog, unsigned int t)
+{
+	struct dc_wdt *wdt = watchdog_get_drvdata(wdog);
+
+	dc_wdt_set(wdt, t * clk_get_rate(wdt->clk));
+	wdog->timeout = t;
+
+	return 0;
+}
+
+static unsigned int dc_wdt_get_timeleft(struct watchdog_device *wdog)
+{
+	struct dc_wdt *wdt = watchdog_get_drvdata(wdog);
+	uint32_t count = readl_relaxed(wdt->base + TIMER_A_COUNT);
+
+	return count / clk_get_rate(wdt->clk);
+}
+
+static struct watchdog_ops dc_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= dc_wdt_start,
+	.stop		= dc_wdt_stop,
+	.set_timeout	= dc_wdt_set_timeout,
+	.get_timeleft	= dc_wdt_get_timeleft,
+};
+
+static struct watchdog_info dc_wdt_info = {
+	.options	= WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE
+			| WDIOF_KEEPALIVEPING,
+	.identity	= "Conexant Digicolor Watchdog",
+};
+
+static struct watchdog_device dc_wdt_wdd = {
+	.info		= &dc_wdt_info,
+	.ops		= &dc_wdt_ops,
+	.min_timeout	= 1,
+};
+
+static int dc_wdt_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct dc_wdt *wdt;
+	int ret;
+
+	wdt = devm_kzalloc(dev, sizeof(struct dc_wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, wdt);
+
+	wdt->base = of_iomap(np, 0);
+	if (!wdt->base) {
+		dev_err(dev, "Failed to remap watchdog regs");
+		return -ENODEV;
+	}
+
+	wdt->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(wdt->clk)) {
+		ret = PTR_ERR(wdt->clk);
+		goto err_iounmap;
+	}
+	dc_wdt_wdd.max_timeout = U32_MAX / clk_get_rate(wdt->clk);
+	dc_wdt_wdd.timeout = dc_wdt_wdd.max_timeout;
+
+	spin_lock_init(&wdt->lock);
+
+	watchdog_set_drvdata(&dc_wdt_wdd, wdt);
+	watchdog_init_timeout(&dc_wdt_wdd, timeout, dev);
+	ret = watchdog_register_device(&dc_wdt_wdd);
+	if (ret) {
+		dev_err(dev, "Failed to register watchdog device");
+		goto err_iounmap;
+	}
+
+	wdt->restart_handler.notifier_call = dc_restart_handler;
+	wdt->restart_handler.priority = 128;
+	ret = register_restart_handler(&wdt->restart_handler);
+	if (ret)
+		dev_warn(&pdev->dev, "cannot register restart handler\n");
+
+	return 0;
+
+err_iounmap:
+	iounmap(wdt->base);
+	return ret;
+}
+
+static int dc_wdt_remove(struct platform_device *pdev)
+{
+	struct dc_wdt *wdt = platform_get_drvdata(pdev);
+
+	unregister_restart_handler(&wdt->restart_handler);
+	watchdog_unregister_device(&dc_wdt_wdd);
+	iounmap(wdt->base);
+
+	return 0;
+}
+
+static void dc_wdt_shutdown(struct platform_device *pdev)
+{
+	dc_wdt_stop(&dc_wdt_wdd);
+}
+
+static const struct of_device_id dc_wdt_of_match[] = {
+	{ .compatible = "cnxt,cx92755-wdt", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, dc_wdt_of_match);
+
+static struct platform_driver dc_wdt_driver = {
+	.probe		= dc_wdt_probe,
+	.remove		= dc_wdt_remove,
+	.shutdown	= dc_wdt_shutdown,
+	.driver = {
+		.name =		"digicolor-wdt",
+		.of_match_table = dc_wdt_of_match,
+	},
+};
+module_platform_driver(dc_wdt_driver);
+
+MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
+MODULE_DESCRIPTION("Driver for Conexant Digicolor watchdog timer");
+MODULE_LICENSE("GPL");
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index d0bb9499d12c..6ea0634345e9 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -35,7 +35,6 @@
 #include <linux/pm.h>
 #include <linux/platform_device.h>
 #include <linux/reboot.h>
-#include <linux/spinlock.h>
 #include <linux/timer.h>
 #include <linux/uaccess.h>
 #include <linux/watchdog.h>
@@ -61,7 +60,6 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
 #define WDT_TIMEOUT		(HZ / 2)
 
 static struct {
-	spinlock_t		lock;
 	void __iomem		*regs;
 	struct clk		*clk;
 	unsigned long		in_use;
@@ -177,7 +175,6 @@ static int dw_wdt_open(struct inode *inode, struct file *filp)
 	/* Make sure we don't get unloaded. */
 	__module_get(THIS_MODULE);
 
-	spin_lock(&dw_wdt.lock);
 	if (!dw_wdt_is_enabled()) {
 		/*
 		 * The watchdog is not currently enabled. Set the timeout to
@@ -190,8 +187,6 @@ static int dw_wdt_open(struct inode *inode, struct file *filp)
 
 	dw_wdt_set_next_heartbeat();
 
-	spin_unlock(&dw_wdt.lock);
-
 	return nonseekable_open(inode, filp);
 }
 
@@ -220,6 +215,7 @@ static ssize_t dw_wdt_write(struct file *filp, const char __user *buf,
 	}
 
 	dw_wdt_set_next_heartbeat();
+	dw_wdt_keepalive();
 	mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT);
 
 	return len;
@@ -348,8 +344,6 @@ static int dw_wdt_drv_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	spin_lock_init(&dw_wdt.lock);
-
 	ret = misc_register(&dw_wdt_miscdev);
 	if (ret)
 		goto out_disable_clk;
diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c
index cbc313d37c59..1687cc2d7122 100644
--- a/drivers/watchdog/gpio_wdt.c
+++ b/drivers/watchdog/gpio_wdt.c
@@ -267,7 +267,16 @@ static struct platform_driver gpio_wdt_driver = {
 	.probe	= gpio_wdt_probe,
 	.remove	= gpio_wdt_remove,
 };
+
+#ifdef CONFIG_GPIO_WATCHDOG_ARCH_INITCALL
+static int __init gpio_wdt_init(void)
+{
+	return platform_driver_register(&gpio_wdt_driver);
+}
+arch_initcall(gpio_wdt_init);
+#else
 module_platform_driver(gpio_wdt_driver);
+#endif
 
 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
 MODULE_DESCRIPTION("GPIO Watchdog");
diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index ada3e44f9932..286369d4f0f5 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -588,7 +588,7 @@ static long hpwdt_ioctl(struct file *file, unsigned int cmd,
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
-	int new_margin;
+	int new_margin, options;
 	int ret = -ENOTTY;
 
 	switch (cmd) {
@@ -608,6 +608,20 @@ static long hpwdt_ioctl(struct file *file, unsigned int cmd,
 		ret = 0;
 		break;
 
+	case WDIOC_SETOPTIONS:
+		ret = get_user(options, p);
+		if (ret)
+			break;
+
+		if (options & WDIOS_DISABLECARD)
+			hpwdt_stop();
+
+		if (options & WDIOS_ENABLECARD) {
+			hpwdt_start();
+			hpwdt_ping();
+		}
+		break;
+
 	case WDIOC_SETTIMEOUT:
 		ret = get_user(new_margin, p);
 		if (ret)
diff --git a/drivers/watchdog/imgpdc_wdt.c b/drivers/watchdog/imgpdc_wdt.c
index 0deaa4f971f5..0f73621827ab 100644
--- a/drivers/watchdog/imgpdc_wdt.c
+++ b/drivers/watchdog/imgpdc_wdt.c
@@ -9,6 +9,35 @@
  *
  * Based on drivers/watchdog/sunxi_wdt.c Copyright (c) 2013 Carlo Caione
  *                                                     2012 Henrik Nordstrom
+ *
+ * Notes
+ * -----
+ * The timeout value is rounded to the next power of two clock cycles.
+ * This is configured using the PDC_WDT_CONFIG register, according to this
+ * formula:
+ *
+ *     timeout = 2^(delay + 1) clock cycles
+ *
+ * Where 'delay' is the value written in PDC_WDT_CONFIG register.
+ *
+ * Therefore, the hardware only allows to program watchdog timeouts, expressed
+ * as a power of two number of watchdog clock cycles. The current implementation
+ * guarantees that the actual watchdog timeout will be _at least_ the value
+ * programmed in the imgpdg_wdt driver.
+ *
+ * The following table shows how the user-configured timeout relates
+ * to the actual hardware timeout (watchdog clock @ 40000 Hz):
+ *
+ * input timeout | WD_DELAY | actual timeout
+ * -----------------------------------
+ *      10       |   18     |  13 seconds
+ *      20       |   19     |  26 seconds
+ *      30       |   20     |  52 seconds
+ *      60       |   21     |  104 seconds
+ *
+ * Albeit coarse, this granularity would suffice most watchdog uses.
+ * If the platform allows it, the user should be able to change the watchdog
+ * clock rate and achieve a finer timeout granularity.
  */
 
 #include <linux/clk.h>
@@ -16,6 +45,7 @@
 #include <linux/log2.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/reboot.h>
 #include <linux/slab.h>
 #include <linux/watchdog.h>
 
@@ -42,7 +72,7 @@
 #define PDC_WDT_MIN_TIMEOUT		1
 #define PDC_WDT_DEF_TIMEOUT		64
 
-static int heartbeat = PDC_WDT_DEF_TIMEOUT;
+static int heartbeat;
 module_param(heartbeat, int, 0);
 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeats in seconds "
 	"(default=" __MODULE_STRING(PDC_WDT_DEF_TIMEOUT) ")");
@@ -57,6 +87,7 @@ struct pdc_wdt_dev {
 	struct clk *wdt_clk;
 	struct clk *sys_clk;
 	void __iomem *base;
+	struct notifier_block restart_handler;
 };
 
 static int pdc_wdt_keepalive(struct watchdog_device *wdt_dev)
@@ -84,18 +115,24 @@ static int pdc_wdt_stop(struct watchdog_device *wdt_dev)
 	return 0;
 }
 
+static void __pdc_wdt_set_timeout(struct pdc_wdt_dev *wdt)
+{
+	unsigned long clk_rate = clk_get_rate(wdt->wdt_clk);
+	unsigned int val;
+
+	val = readl(wdt->base + PDC_WDT_CONFIG) & ~PDC_WDT_CONFIG_DELAY_MASK;
+	val |= order_base_2(wdt->wdt_dev.timeout * clk_rate) - 1;
+	writel(val, wdt->base + PDC_WDT_CONFIG);
+}
+
 static int pdc_wdt_set_timeout(struct watchdog_device *wdt_dev,
 			       unsigned int new_timeout)
 {
-	unsigned int val;
 	struct pdc_wdt_dev *wdt = watchdog_get_drvdata(wdt_dev);
-	unsigned long clk_rate = clk_get_rate(wdt->wdt_clk);
 
 	wdt->wdt_dev.timeout = new_timeout;
 
-	val = readl(wdt->base + PDC_WDT_CONFIG) & ~PDC_WDT_CONFIG_DELAY_MASK;
-	val |= order_base_2(new_timeout * clk_rate) - 1;
-	writel(val, wdt->base + PDC_WDT_CONFIG);
+	__pdc_wdt_set_timeout(wdt);
 
 	return 0;
 }
@@ -106,6 +143,8 @@ static int pdc_wdt_start(struct watchdog_device *wdt_dev)
 	unsigned int val;
 	struct pdc_wdt_dev *wdt = watchdog_get_drvdata(wdt_dev);
 
+	__pdc_wdt_set_timeout(wdt);
+
 	val = readl(wdt->base + PDC_WDT_CONFIG);
 	val |= PDC_WDT_CONFIG_ENABLE;
 	writel(val, wdt->base + PDC_WDT_CONFIG);
@@ -128,8 +167,21 @@ static const struct watchdog_ops pdc_wdt_ops = {
 	.set_timeout	= pdc_wdt_set_timeout,
 };
 
+static int pdc_wdt_restart(struct notifier_block *this, unsigned long mode,
+			   void *cmd)
+{
+	struct pdc_wdt_dev *wdt = container_of(this, struct pdc_wdt_dev,
+					       restart_handler);
+
+	/* Assert SOFT_RESET */
+	writel(0x1, wdt->base + PDC_WDT_SOFT_RESET);
+