Merge tag 'at91-cleanup3' into at91-4.1-multiplatform

Third batch of cleanup for 4.1:
- System Timer (ST) for at91rm9200 re-work (syscon/regmap):
  - watchdog
  - restart handler
  - timer as a proper clocksource
  => remove mach dependency + cleanup

13 files changed, 164 insertions, 166 deletions

diff --git a/Documentation/devicetree/bindings/arm/atmel-at91.txt b/Documentation/devicetree/bindings/arm/atmel-at91.txt
index ad319f84f560..2e99b5b57350 100644
--- a/Documentation/devicetree/bindings/arm/atmel-at91.txt
+++ b/Documentation/devicetree/bindings/arm/atmel-at91.txt
@@ -46,10 +46,12 @@ PIT Timer required properties:
   shared across all System Controller members.
 
 System Timer (ST) required properties:
-- compatible: Should be "atmel,at91rm9200-st"
+- compatible: Should be "atmel,at91rm9200-st", "syscon", "simple-mfd"
 - reg: Should contain registers location and length
 - interrupts: Should contain interrupt for the ST which is the IRQ line
   shared across all System Controller members.
+Its subnodes can be:
+- watchdog: compatible should be "atmel,at91rm9200-wdt"
 
 TC/TCLIB Timer required properties:
 - compatible: Should be "atmel,<chip>-tcb".
diff --git a/arch/arm/boot/dts/at91rm9200.dtsi b/arch/arm/boot/dts/at91rm9200.dtsi
index c515e4b160be..4fb333bd1f85 100644
--- a/arch/arm/boot/dts/at91rm9200.dtsi
+++ b/arch/arm/boot/dts/at91rm9200.dtsi
@@ -356,9 +356,13 @@
 			};
 
 			st: timer@fffffd00 {
-				compatible = "atmel,at91rm9200-st";
+				compatible = "atmel,at91rm9200-st", "syscon", "simple-mfd";
 				reg = <0xfffffd00 0x100>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+
+				watchdog {
+					compatible = "atmel,at91rm9200-wdt";
+				};
 			};
 
 			rtc: rtc@fffffe00 {
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 4da6bae047f3..24b59c75f6af 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -77,6 +77,7 @@ if SOC_SAM_V4_V5
 config SOC_AT91RM9200
 	bool "AT91RM9200"
 	select ATMEL_AIC_IRQ
+	select ATMEL_ST
 	select COMMON_CLK_AT91
 	select CPU_ARM920T
 	select GENERIC_CLOCKEVENTS
diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index ea54c9824d89..38aaef7b994e 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -7,7 +7,7 @@ obj-y		:= soc.o
 obj-$(CONFIG_SOC_AT91SAM9)	+= sam9_smc.o
 
 # CPU-specific support
-obj-$(CONFIG_SOC_AT91RM9200)	+= at91rm9200.o at91rm9200_time.o
+obj-$(CONFIG_SOC_AT91RM9200)	+= at91rm9200.o
 obj-$(CONFIG_SOC_AT91SAM9)	+= at91sam9.o
 obj-$(CONFIG_SOC_SAMA5)		+= sama5.o
 
diff --git a/arch/arm/mach-at91/at91rm9200.c b/arch/arm/mach-at91/at91rm9200.c
index bfc9aed90b91..eaf58f88ef5d 100644
--- a/arch/arm/mach-at91/at91rm9200.c
+++ b/arch/arm/mach-at91/at91rm9200.c
@@ -15,8 +15,6 @@
 #include <asm/mach/arch.h>
 #include <asm/system_misc.h>
 
-#include <mach/at91_st.h>
-
 #include "generic.h"
 #include "soc.h"
 
@@ -25,21 +23,6 @@ static const struct at91_soc rm9200_socs[] = {
 	{ /* sentinel */ },
 };
 
-static void at91rm9200_restart(enum reboot_mode reboot_mode, const char *cmd)
-{
-	/*
-	 * Perform a hardware reset with the use of the Watchdog timer.
-	 */
-	at91_st_write(AT91_ST_WDMR, AT91_ST_RSTEN | AT91_ST_EXTEN | 1);
-	at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
-}
-
-static void __init at91rm9200_dt_timer_init(void)
-{
-	of_clk_init(NULL);
-	at91rm9200_timer_init();
-}
-
 static void __init at91rm9200_dt_device_init(void)
 {
 	struct soc_device *soc;
@@ -52,7 +35,6 @@ static void __init at91rm9200_dt_device_init(void)
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, soc_dev);
 
 	arm_pm_idle = at91rm9200_idle;
-	arm_pm_restart = at91rm9200_restart;
 	at91rm9200_pm_init();
 }
 
@@ -62,7 +44,6 @@ static const char *at91rm9200_dt_board_compat[] __initconst = {
 };
 
 DT_MACHINE_START(at91rm9200_dt, "Atmel AT91RM9200")
-	.init_time      = at91rm9200_dt_timer_init,
 	.init_machine	= at91rm9200_dt_device_init,
 	.dt_compat	= at91rm9200_dt_board_compat,
 MACHINE_END
diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h
index 2b396c4e1fc1..b0fa7dc7286d 100644
--- a/arch/arm/mach-at91/generic.h
+++ b/arch/arm/mach-at91/generic.h
@@ -18,9 +18,6 @@
 extern void __init at91_map_io(void);
 extern void __init at91_alt_map_io(void);
 
- /* Timer */
-extern void at91rm9200_timer_init(void);
-
 /* idle */
 extern void at91rm9200_idle(void);
 extern void at91sam9_idle(void);
diff --git a/arch/arm/mach-at91/include/mach/at91_st.h b/arch/arm/mach-at91/include/mach/at91_st.h
deleted file mode 100644
index 67fdbd13c3ed..000000000000
--- a/arch/arm/mach-at91/include/mach/at91_st.h
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * arch/arm/mach-at91/include/mach/at91_st.h
- *
- * Copyright (C) 2005 Ivan Kokshaysky
- * Copyright (C) SAN People
- *
- * System Timer (ST) - System peripherals registers.
- * Based on AT91RM9200 datasheet revision E.
- *
- * 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.
- */
-
-#ifndef AT91_ST_H
-#define AT91_ST_H
-
-#ifndef __ASSEMBLY__
-extern void __iomem *at91_st_base;
-
-#define at91_st_read(field) \
-	__raw_readl(at91_st_base + field)
-
-#define at91_st_write(field, value) \
-	__raw_writel(value, at91_st_base + field)
-#else
-.extern at91_st_base
-#endif
-
-#define	AT91_ST_CR		0x00			/* Control Register */
-#define 	AT91_ST_WDRST		(1 << 0)		/* Watchdog Timer Restart */
-
-#define	AT91_ST_PIMR		0x04			/* Period Interval Mode Register */
-#define		AT91_ST_PIV		(0xffff <<  0)		/* Period Interval Value */
-
-#define	AT91_ST_WDMR		0x08			/* Watchdog Mode Register */
-#define		AT91_ST_WDV		(0xffff <<  0)		/* Watchdog Counter Value */
-#define		AT91_ST_RSTEN		(1	<< 16)		/* Reset Enable */
-#define		AT91_ST_EXTEN		(1	<< 17)		/* External Signal Assertion Enable */
-
-#define	AT91_ST_RTMR		0x0c			/* Real-time Mode Register */
-#define		AT91_ST_RTPRES		(0xffff <<  0)		/* Real-time Prescalar Value */
-
-#define	AT91_ST_SR		0x10			/* Status Register */
-#define		AT91_ST_PITS		(1 << 0)		/* Period Interval Timer Status */
-#define		AT91_ST_WDOVF		(1 << 1) 		/* Watchdog Overflow */
-#define		AT91_ST_RTTINC		(1 << 2) 		/* Real-time Timer Increment */
-#define		AT91_ST_ALMS		(1 << 3) 		/* Alarm Status */
-
-#define	AT91_ST_IER		0x14			/* Interrupt Enable Register */
-#define	AT91_ST_IDR		0x18			/* Interrupt Disable Register */
-#define	AT91_ST_IMR		0x1c			/* Interrupt Mask Register */
-
-#define	AT91_ST_RTAR		0x20			/* Real-time Alarm Register */
-#define		AT91_ST_ALMV		(0xfffff << 0)		/* Alarm Value */
-
-#define	AT91_ST_CRTR		0x24			/* Current Real-time Register */
-#define		AT91_ST_CRTV		(0xfffff << 0)		/* Current Real-Time Value */
-
-#endif
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 68161f7a07d6..168035883afa 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -143,6 +143,10 @@ config ATMEL_PIT
 	select CLKSRC_OF if OF
 	def_bool SOC_AT91SAM9 || SOC_SAMA5
 
+config ATMEL_ST
+	bool
+	select CLKSRC_OF
+
 config CLKSRC_METAG_GENERIC
 	def_bool y if METAG
 	help
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 752d5c70b0ef..5b85f6adb258 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -1,5 +1,6 @@
 obj-$(CONFIG_CLKSRC_OF)	+= clksrc-of.o
 obj-$(CONFIG_ATMEL_PIT)		+= timer-atmel-pit.o
+obj-$(CONFIG_ATMEL_ST)		+= timer-atmel-st.o
 obj-$(CONFIG_ATMEL_TCB_CLKSRC)	+= tcb_clksrc.o
 obj-$(CONFIG_X86_PM_TIMER)	+= acpi_pm.o
 obj-$(CONFIG_SCx200HR_TIMER)	+= scx200_hrt.o
diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/drivers/clocksource/timer-atmel-st.c
index b00d09555f2b..1692e17e096b 100644
--- a/arch/arm/mach-at91/at91rm9200_time.c
+++ b/drivers/clocksource/timer-atmel-st.c
@@ -24,19 +24,17 @@
 #include <linux/irq.h>
 #include <linux/clockchips.h>
 #include <linux/export.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/atmel-st.h>
 #include <linux/of_irq.h>
-
-#include <asm/mach/time.h>
-
-#include <mach/at91_st.h>
-#include <mach/hardware.h>
+#include <linux/regmap.h>
 
 static unsigned long last_crtr;
 static u32 irqmask;
 static struct clock_event_device clkevt;
+static struct regmap *regmap_st;
 
+#define AT91_SLOW_CLOCK		32768
 #define RM9200_TIMER_LATCH	((AT91_SLOW_CLOCK + HZ/2) / HZ)
 
 /*
@@ -46,11 +44,11 @@ static struct clock_event_device clkevt;
  */
 static inline unsigned long read_CRTR(void)
 {
-	unsigned long x1, x2;
+	unsigned int x1, x2;
 
-	x1 = at91_st_read(AT91_ST_CRTR);
+	regmap_read(regmap_st, AT91_ST_CRTR, &x1);
 	do {
-		x2 = at91_st_read(AT91_ST_CRTR);
+		regmap_read(regmap_st, AT91_ST_CRTR, &x2);
 		if (x1 == x2)
 			break;
 		x1 = x2;
@@ -63,7 +61,10 @@ static inline unsigned long read_CRTR(void)
  */
 static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id)
 {
-	u32	sr = at91_st_read(AT91_ST_SR) & irqmask;
+	u32 sr;
+
+	regmap_read(regmap_st, AT91_ST_SR, &sr);
+	sr &= irqmask;
 
 	/*
 	 * irqs should be disabled here, but as the irq is shared they are only
@@ -92,13 +93,6 @@ static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id)
 	return IRQ_NONE;
 }
 
-static struct irqaction at91rm9200_timer_irq = {
-	.name		= "at91_tick",
-	.flags		= IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
-	.handler	= at91rm9200_timer_interrupt,
-	.irq		= NR_IRQS_LEGACY + AT91_ID_SYS,
-};
-
 static cycle_t read_clk32k(struct clocksource *cs)
 {
 	return read_CRTR();
@@ -115,23 +109,25 @@ static struct clocksource clk32k = {
 static void
 clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 {
+	unsigned int val;
+
 	/* Disable and flush pending timer interrupts */
-	at91_st_write(AT91_ST_IDR, AT91_ST_PITS | AT91_ST_ALMS);
-	at91_st_read(AT91_ST_SR);
+	regmap_write(regmap_st, AT91_ST_IDR, AT91_ST_PITS | AT91_ST_ALMS);
+	regmap_read(regmap_st, AT91_ST_SR, &val);
 
 	last_crtr = read_CRTR();
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
 		/* PIT for periodic irqs; fixed rate of 1/HZ */
 		irqmask = AT91_ST_PITS;
-		at91_st_write(AT91_ST_PIMR, RM9200_TIMER_LATCH);
+		regmap_write(regmap_st, AT91_ST_PIMR, RM9200_TIMER_LATCH);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		/* ALM for oneshot irqs, set by next_event()
 		 * before 32 seconds have passed
 		 */
 		irqmask = AT91_ST_ALMS;
-		at91_st_write(AT91_ST_RTAR, last_crtr);
+		regmap_write(regmap_st, AT91_ST_RTAR, last_crtr);
 		break;
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	case CLOCK_EVT_MODE_UNUSED:
@@ -139,7 +135,7 @@ clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 		irqmask = 0;
 		break;
 	}
-	at91_st_write(AT91_ST_IER, irqmask);
+	regmap_write(regmap_st, AT91_ST_IER, irqmask);
 }
 
 static int
@@ -147,6 +143,7 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
 {
 	u32		alm;
 	int		status = 0;
+	unsigned int	val;
 
 	BUG_ON(delta < 2);
 
@@ -162,12 +159,12 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
 	alm = read_CRTR();
 
 	/* Cancel any pending alarm; flush any pending IRQ */
-	at91_st_write(AT91_ST_RTAR, alm);
-	at91_st_read(AT91_ST_SR);
+	regmap_write(regmap_st, AT91_ST_RTAR, alm);
+	regmap_read(regmap_st, AT91_ST_SR, &val);
 
 	/* Schedule alarm by writing RTAR. */
 	alm += delta;
-	at91_st_write(AT91_ST_RTAR, alm);
+	regmap_write(regmap_st, AT91_ST_RTAR, alm);
 
 	return status;
 }
@@ -180,66 +177,40 @@ static struct clock_event_device clkevt = {
 	.set_mode	= clkevt32k_mode,
 };
 
-void __iomem *at91_st_base;
-EXPORT_SYMBOL_GPL(at91_st_base);
-
-static const struct of_device_id at91rm9200_st_timer_ids[] = {
-	{ .compatible = "atmel,at91rm9200-st" },
-	{ /* sentinel */ }
-};
-
-static int __init of_at91rm9200_st_init(void)
-{
-	struct device_node *np;
-	int ret;
-
-	np = of_find_matching_node(NULL, at91rm9200_st_timer_ids);
-	if (!np)
-		goto err;
-
-	at91_st_base = of_iomap(np, 0);
-	if (!at91_st_base)
-		goto node_err;
-
-	/* Get the interrupts property */
-	ret = irq_of_parse_and_map(np, 0);
-	if (!ret)
-		goto ioremap_err;
-	at91rm9200_timer_irq.irq = ret;
-
-	of_node_put(np);
-
-	return 0;
-
-ioremap_err:
-	iounmap(at91_st_base);
-node_err:
-	of_node_put(np);
-err:
-	return -EINVAL;
-}
-
 /*
  * ST (system timer) module supports both clockevents and clocksource.
  */
-void __init at91rm9200_timer_init(void)
+static void __init atmel_st_timer_init(struct device_node *node)
 {
-	/* For device tree enabled device: initialize here */
-	of_at91rm9200_st_init();
+	unsigned int val;
+	int irq, ret;
+
+	regmap_st = syscon_node_to_regmap(node);
+	if (IS_ERR(regmap_st))
+		panic(pr_fmt("Unable to get regmap\n"));
 
 	/* Disable all timer interrupts, and clear any pending ones */
-	at91_st_write(AT91_ST_IDR,
+	regmap_write(regmap_st, AT91_ST_IDR,
 		AT91_ST_PITS | AT91_ST_WDOVF | AT91_ST_RTTINC | AT91_ST_ALMS);
-	at91_st_read(AT91_ST_SR);
+	regmap_read(regmap_st, AT91_ST_SR, &val);
+
+	/* Get the interrupts property */
+	irq  = irq_of_parse_and_map(node, 0);
+	if (!irq)
+		panic(pr_fmt("Unable to get IRQ from DT\n"));
 
 	/* Make IRQs happen for the system timer */
-	setup_irq(at91rm9200_timer_irq.irq, &at91rm9200_timer_irq);
+	ret = request_irq(irq, at91rm9200_timer_interrupt,
+			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+			  "at91_tick", regmap_st);
+	if (ret)
+		panic(pr_fmt("Unable to setup IRQ\n"));
 
 	/* The 32KiHz "Slow Clock" (tick every 30517.58 nanoseconds) is used
 	 * directly for the clocksource and all clockevents, after adjusting
 	 * its prescaler from the 1 Hz default.
 	 */
-	at91_st_write(AT91_ST_RTMR, 1);
+	regmap_write(regmap_st, AT91_ST_RTMR, 1);
 
 	/* Setup timer clockevent, with minimum of two ticks (important!!) */
 	clkevt.cpumask = cpumask_of(0);
@@ -249,3 +220,5 @@ void __init at91rm9200_timer_init(void)
 	/* register clocksource */
 	clocksource_register_hz(&clk32k, AT91_SLOW_CLOCK);
 }
+CLOCKSOURCE_OF_DECLARE(atmel_st_timer, "atmel,at91rm9200-st",
+		       atmel_st_timer_init);
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 16f202350997..ce4f3a7f95fd 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -154,7 +154,7 @@ config ARM_SP805_WATCHDOG
 
 config AT91RM9200_WATCHDOG
 	tristate "AT91RM9200 watchdog"
-	depends on SOC_AT91RM9200
+	depends on SOC_AT91RM9200 && MFD_SYSCON
 	help
 	  Watchdog timer embedded into AT91RM9200 chips. This will reboot your
 	  system when the timeout is reached.
diff --git a/drivers/watchdog/at91rm9200_wdt.c b/drivers/watchdog/at91rm9200_wdt.c
index d244112d5b6f..41cecb55766c 100644
--- a/drivers/watchdog/at91rm9200_wdt.c
+++ b/drivers/watchdog/at91rm9200_wdt.c
@@ -12,27 +12,32 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/bitops.h>
+#include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/atmel-st.h>
 #include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
 #include <linux/types.h>
 #include <linux/watchdog.h>
 #include <linux/uaccess.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
-#include <mach/at91_st.h>
 
 #define WDT_DEFAULT_TIME	5	/* seconds */
 #define WDT_MAX_TIME		256	/* seconds */
 
 static int wdt_time = WDT_DEFAULT_TIME;
 static bool nowayout = WATCHDOG_NOWAYOUT;
+static struct regmap *regmap_st;
 
 module_param(wdt_time, int, 0);
 MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="
@@ -50,12 +55,33 @@ static unsigned long at91wdt_busy;
 
 /* ......................................................................... */
 
+static int at91rm9200_restart(struct notifier_block *this,
+					unsigned long mode, void *cmd)
+{
+	/*
+	 * Perform a hardware reset with the use of the Watchdog timer.
+	 */
+	regmap_write(regmap_st, AT91_ST_WDMR,
+		     AT91_ST_RSTEN | AT91_ST_EXTEN | 1);
+	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
+
+	mdelay(2000);
+
+	pr_emerg("Unable to restart system\n");
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block at91rm9200_restart_nb = {
+	.notifier_call = at91rm9200_restart,
+	.priority = 192,
+};
+
 /*
  * Disable the watchdog.
  */
 static inline void at91_wdt_stop(void)
 {
-	at91_st_write(AT91_ST_WDMR, AT91_ST_EXTEN);
+	regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN);
 }
 
 /*
@@ -63,9 +89,9 @@ static inline void at91_wdt_stop(void)
  */
 static inline void at91_wdt_start(void)
 {
-	at91_st_write(AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
+	regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
 				(((65536 * wdt_time) >> 8) & AT91_ST_WDV));
-	at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
+	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
 }
 
 /*
@@ -73,7 +99,7 @@ static inline void at91_wdt_start(void)
  */
 static inline void at91_wdt_reload(void)
 {
-	at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
+	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
 }
 
 /* ......................................................................... */
@@ -203,16 +229,32 @@ static struct miscdevice at91wdt_miscdev = {
 
 static int at91wdt_probe(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
+	struct device *parent;
 	int res;
 
 	if (at91wdt_miscdev.parent)
 		return -EBUSY;
 	at91wdt_miscdev.parent = &pdev->dev;
 
+	parent = dev->parent;
+	if (!parent) {
+		dev_err(dev, "no parent\n");
+		return -ENODEV;
+	}
+
+	regmap_st = syscon_node_to_regmap(parent->of_node);
+	if (!regmap_st)
+		return -ENODEV;
+
 	res = misc_register(&at91wdt_miscdev);
 	if (res)
 		return res;
 
+	res = register_restart_handler(&at91rm9200_restart_nb);
+	if (res)
+		dev_warn(dev, "failed to register restart handler\n");
+
 	pr_info("AT91 Watchdog Timer enabled (%d seconds%s)\n",
 		wdt_time, nowayout ? ", nowayout" : "");
 	return 0;
@@ -220,8 +262,13 @@ static int at91wdt_probe(struct platform_device *pdev)
 
 static int at91wdt_remove(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
 	int res;
 
+	res = unregister_restart_handler(&at91rm9200_restart_nb);
+	if (res)
+		dev_warn(dev, "failed to unregister restart handler\n");
+
 	res = misc_deregister(&at91wdt_miscdev);
 	if (!res)
 		at91wdt_miscdev.parent = NULL;
@@ -267,7 +314,7 @@ static struct platform_driver at91wdt_driver = {
 	.suspend	= at91wdt_suspend,
 	.resume		= at91wdt_resume,
 	.driver		= {
-		.name	= "at91_wdt",
+		.name	= "atmel_st_watchdog",
 		.of_match_table = at91_wdt_dt_ids,
 	},
 };
@@ -296,4 +343,4 @@ module_exit(at91_wdt_exit);
 MODULE_AUTHOR("Andrew Victor");
 MODULE_DESCRIPTION("Watchdog driver for Atmel AT91RM9200");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:at91_wdt");
+MODULE_ALIAS("platform:atmel_st_watchdog");
diff --git a/include/linux/mfd/syscon/atmel-st.h b/include/linux/mfd/syscon/atmel-st.h
new file mode 100644
index 000000000000..8acf1ec1fa32
--- /dev/null
+++ b/include/linux/mfd/syscon/atmel-st.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2005 Ivan Kokshaysky
+ * Copyright (C) SAN People
+ *
+ * System Timer (ST) - System peripherals registers.
+ * Based on AT91RM9200 datasheet revision E.
+ *
+ * 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.
+ */
+
+#ifndef _LINUX_MFD_SYSCON_ATMEL_ST_H
+#define _LINUX_MFD_SYSCON_ATMEL_ST_H
+
+#include <linux/bitops.h>
+
+#define AT91_ST_CR	0x00	/* Control Register */
+#define		AT91_ST_WDRST	BIT(0)	/* Watchdog Timer Restart */
+
+#define AT91_ST_PIMR	0x04	/* Period Interval Mode Register */
+#define		AT91_ST_PIV	0xffff	/* Period Interval Value */
+
+#define AT91_ST_WDMR	0x08	/* Watchdog Mode Register */
+#define		AT91_ST_WDV	0xffff	/* Watchdog Counter Value */
+#define		AT91_ST_RSTEN	BIT(16)	/* Reset Enable */
+#define		AT91_ST_EXTEN	BIT(17)	/* External Signal Assertion Enable */
+
+#define AT91_ST_RTMR	0x0c	/* Real-time Mode Register */
+#define		AT91_ST_RTPRES	0xffff	/* Real-time Prescalar Value */
+
+#define AT91_ST_SR	0x10	/* Status Register */
+#define		AT91_ST_PITS	BIT(0)	/* Period Interval Timer Status */
+#define		AT91_ST_WDOVF	BIT(1)	/* Watchdog Overflow */
+#define		AT91_ST_RTTINC	BIT(2)	/* Real-time Timer Increment */
+#define		AT91_ST_ALMS	BIT(3)	/* Alarm Status */
+
+#define AT91_ST_IER	0x14	/* Interrupt Enable Register */
+#define AT91_ST_IDR	0x18	/* Interrupt Disable Register */
+#define AT91_ST_IMR	0x1c	/* Interrupt Mask Register */
+
+#define AT91_ST_RTAR	0x20	/* Real-time Alarm Register */
+#define		AT91_ST_ALMV	0xfffff	/* Alarm Value */
+
+#define AT91_ST_CRTR	0x24	/* Current Real-time Register */
+#define		AT91_ST_CRTV	0xfffff	/* Current Real-Time Value */
+
+#endif /* _LINUX_MFD_SYSCON_ATMEL_ST_H */