drivers/clocksource/em_sti.c - kernel/msm-4.9 - Gitiles

 /*
  * Emma Mobile Timer Support - STI
  *
  *  Copyright (C) 2012 Magnus Damm
  *
  * 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
  *
  * 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.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */

 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/ioport.h>
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/irq.h>
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
 #include <linux/slab.h>
 #include <linux/module.h>

 enum { USER_CLOCKSOURCE, USER_CLOCKEVENT, USER_NR };

 struct em_sti_priv {
 	void __iomem *base;
 	struct clk *clk;
 	struct platform_device *pdev;
 	unsigned int active[USER_NR];
 	unsigned long rate;
 	raw_spinlock_t lock;
 	struct clock_event_device ced;
 	struct clocksource cs;
 };

 #define STI_CONTROL 0x00
 #define STI_COMPA_H 0x10
 #define STI_COMPA_L 0x14
 #define STI_COMPB_H 0x18
 #define STI_COMPB_L 0x1c
 #define STI_COUNT_H 0x20
 #define STI_COUNT_L 0x24
 #define STI_COUNT_RAW_H 0x28
 #define STI_COUNT_RAW_L 0x2c
 #define STI_SET_H 0x30
 #define STI_SET_L 0x34
 #define STI_INTSTATUS 0x40
 #define STI_INTRAWSTATUS 0x44
 #define STI_INTENSET 0x48
 #define STI_INTENCLR 0x4c
 #define STI_INTFFCLR 0x50

 static inline unsigned long em_sti_read(struct em_sti_priv *p, int offs)
 {
 	return ioread32(p->base + offs);
 }

 static inline void em_sti_write(struct em_sti_priv *p, int offs,
 				unsigned long value)
 {
 	iowrite32(value, p->base + offs);
 }

 static int em_sti_enable(struct em_sti_priv *p)
 {
 	int ret;

 	/* enable clock */
 	ret = clk_enable(p->clk);
 	if (ret) {
 		dev_err(&p->pdev->dev, "cannot enable clock\n");
 		return ret;
 	}

 	/* configure channel, periodic mode and maximum timeout */
 	p->rate = clk_get_rate(p->clk);

 	/* reset the counter */
 	em_sti_write(p, STI_SET_H, 0x40000000);
 	em_sti_write(p, STI_SET_L, 0x00000000);

 	/* mask and clear pending interrupts */
 	em_sti_write(p, STI_INTENCLR, 3);
 	em_sti_write(p, STI_INTFFCLR, 3);

 	/* enable updates of counter registers */
 	em_sti_write(p, STI_CONTROL, 1);

 	return 0;
 }

 static void em_sti_disable(struct em_sti_priv *p)
 {
 	/* mask interrupts */
 	em_sti_write(p, STI_INTENCLR, 3);

 	/* stop clock */
 	clk_disable(p->clk);
 }

 static cycle_t em_sti_count(struct em_sti_priv *p)
 {
 	cycle_t ticks;
 	unsigned long flags;

 	/* the STI hardware buffers the 48-bit count, but to
 	 * break it out into two 32-bit access the registers
 	 * must be accessed in a certain order.
 	 * Always read STI_COUNT_H before STI_COUNT_L.
 	 */
 	raw_spin_lock_irqsave(&p->lock, flags);
 	ticks = (cycle_t)(em_sti_read(p, STI_COUNT_H) & 0xffff) << 32;
 	ticks |= em_sti_read(p, STI_COUNT_L);
 	raw_spin_unlock_irqrestore(&p->lock, flags);

 	return ticks;
 }

 static cycle_t em_sti_set_next(struct em_sti_priv *p, cycle_t next)
 {
 	unsigned long flags;

 	raw_spin_lock_irqsave(&p->lock, flags);

 	/* mask compare A interrupt */
 	em_sti_write(p, STI_INTENCLR, 1);

 	/* update compare A value */
 	em_sti_write(p, STI_COMPA_H, next >> 32);
 	em_sti_write(p, STI_COMPA_L, next & 0xffffffff);

 	/* clear compare A interrupt source */
 	em_sti_write(p, STI_INTFFCLR, 1);

 	/* unmask compare A interrupt */
 	em_sti_write(p, STI_INTENSET, 1);

 	raw_spin_unlock_irqrestore(&p->lock, flags);

 	return next;
 }

 static irqreturn_t em_sti_interrupt(int irq, void *dev_id)
 {
 	struct em_sti_priv *p = dev_id;

 	p->ced.event_handler(&p->ced);
 	return IRQ_HANDLED;
 }

 static int em_sti_start(struct em_sti_priv *p, unsigned int user)
 {
 	unsigned long flags;
 	int used_before;
 	int ret = 0;

 	raw_spin_lock_irqsave(&p->lock, flags);
 	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
 	if (!used_before)
 		ret = em_sti_enable(p);

 	if (!ret)
 		p->active[user] = 1;
 	raw_spin_unlock_irqrestore(&p->lock, flags);

 	return ret;
 }

 static void em_sti_stop(struct em_sti_priv *p, unsigned int user)
 {
 	unsigned long flags;
 	int used_before, used_after;

 	raw_spin_lock_irqsave(&p->lock, flags);
 	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
 	p->active[user] = 0;
 	used_after = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];

 	if (used_before && !used_after)
 		em_sti_disable(p);
 	raw_spin_unlock_irqrestore(&p->lock, flags);
 }

 static struct em_sti_priv *cs_to_em_sti(struct clocksource *cs)
 {
 	return container_of(cs, struct em_sti_priv, cs);
 }

 static cycle_t em_sti_clocksource_read(struct clocksource *cs)
 {
 	return em_sti_count(cs_to_em_sti(cs));
 }

 static int em_sti_clocksource_enable(struct clocksource *cs)
 {
 	int ret;
 	struct em_sti_priv *p = cs_to_em_sti(cs);

 	ret = em_sti_start(p, USER_CLOCKSOURCE);
 	if (!ret)
 		__clocksource_updatefreq_hz(cs, p->rate);
 	return ret;
 }

 static void em_sti_clocksource_disable(struct clocksource *cs)
 {
 	em_sti_stop(cs_to_em_sti(cs), USER_CLOCKSOURCE);
 }

 static void em_sti_clocksource_resume(struct clocksource *cs)
 {
 	em_sti_clocksource_enable(cs);
 }

 static int em_sti_register_clocksource(struct em_sti_priv *p)
 {
 	struct clocksource *cs = &p->cs;

 	memset(cs, 0, sizeof(*cs));
 	cs->name = dev_name(&p->pdev->dev);
 	cs->rating = 200;
 	cs->read = em_sti_clocksource_read;
 	cs->enable = em_sti_clocksource_enable;
 	cs->disable = em_sti_clocksource_disable;
 	cs->suspend = em_sti_clocksource_disable;
 	cs->resume = em_sti_clocksource_resume;
 	cs->mask = CLOCKSOURCE_MASK(48);
 	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;

 	dev_info(&p->pdev->dev, "used as clock source\n");

 	/* Register with dummy 1 Hz value, gets updated in ->enable() */
 	clocksource_register_hz(cs, 1);
 	return 0;
 }

 static struct em_sti_priv *ced_to_em_sti(struct clock_event_device *ced)
 {
 	return container_of(ced, struct em_sti_priv, ced);
 }

 static void em_sti_clock_event_mode(enum clock_event_mode mode,
 				    struct clock_event_device *ced)
 {
 	struct em_sti_priv *p = ced_to_em_sti(ced);

 	/* deal with old setting first */
 	switch (ced->mode) {
 	case CLOCK_EVT_MODE_ONESHOT:
 		em_sti_stop(p, USER_CLOCKEVENT);
 		break;
 	default:
 		break;
 	}

 	switch (mode) {
 	case CLOCK_EVT_MODE_ONESHOT:
 		dev_info(&p->pdev->dev, "used for oneshot clock events\n");
 		em_sti_start(p, USER_CLOCKEVENT);
 		clockevents_config(&p->ced, p->rate);
 		break;
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	case CLOCK_EVT_MODE_UNUSED:
 		em_sti_stop(p, USER_CLOCKEVENT);
 		break;
 	default:
 		break;
 	}
 }

 static int em_sti_clock_event_next(unsigned long delta,
 				   struct clock_event_device *ced)
 {
 	struct em_sti_priv *p = ced_to_em_sti(ced);
 	cycle_t next;
 	int safe;

 	next = em_sti_set_next(p, em_sti_count(p) + delta);
 	safe = em_sti_count(p) < (next - 1);

 	return !safe;
 }

 static void em_sti_register_clockevent(struct em_sti_priv *p)
 {
 	struct clock_event_device *ced = &p->ced;

 	memset(ced, 0, sizeof(*ced));
 	ced->name = dev_name(&p->pdev->dev);
 	ced->features = CLOCK_EVT_FEAT_ONESHOT;
 	ced->rating = 200;
 	ced->cpumask = cpumask_of(0);
 	ced->set_next_event = em_sti_clock_event_next;
 	ced->set_mode = em_sti_clock_event_mode;

 	dev_info(&p->pdev->dev, "used for clock events\n");

 	/* Register with dummy 1 Hz value, gets updated in ->set_mode() */
 	clockevents_config_and_register(ced, 1, 2, 0xffffffff);
 }

 static int em_sti_probe(struct platform_device *pdev)
 {
 	struct em_sti_priv *p;
 	struct resource *res;
 	int irq;

 	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
 	if (p == NULL) {
 		dev_err(&pdev->dev, "failed to allocate driver data\n");
 		return -ENOMEM;
 	}

 	p->pdev = pdev;
 	platform_set_drvdata(pdev, p);

 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
 		dev_err(&pdev->dev, "failed to get irq\n");
 		return -EINVAL;
 	}

 	/* map memory, let base point to the STI instance */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	p->base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(p->base))
 		return PTR_ERR(p->base);

 	/* get hold of clock */
 	p->clk = devm_clk_get(&pdev->dev, "sclk");
 	if (IS_ERR(p->clk)) {
 		dev_err(&pdev->dev, "cannot get clock\n");
 		return PTR_ERR(p->clk);
 	}

 	if (devm_request_irq(&pdev->dev, irq, em_sti_interrupt,
 			     IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
 			     dev_name(&pdev->dev), p)) {
 		dev_err(&pdev->dev, "failed to request low IRQ\n");
 		return -ENOENT;
 	}

 	raw_spin_lock_init(&p->lock);
 	em_sti_register_clockevent(p);
 	em_sti_register_clocksource(p);
 	return 0;
 }

 static int em_sti_remove(struct platform_device *pdev)
 {
 	return -EBUSY; /* cannot unregister clockevent and clocksource */
 }

 static const struct of_device_id em_sti_dt_ids[] = {
 	{ .compatible = "renesas,em-sti", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, em_sti_dt_ids);

 static struct platform_driver em_sti_device_driver = {
 	.probe		= em_sti_probe,
 	.remove		= em_sti_remove,
 	.driver		= {
 		.name	= "em_sti",
 		.of_match_table = em_sti_dt_ids,
 	}
 };

 static int __init em_sti_init(void)
 {
 	return platform_driver_register(&em_sti_device_driver);
 }

 static void __exit em_sti_exit(void)
 {
 	platform_driver_unregister(&em_sti_device_driver);
 }

 subsys_initcall(em_sti_init);
 module_exit(em_sti_exit);

 MODULE_AUTHOR("Magnus Damm");
 MODULE_DESCRIPTION("Renesas Emma Mobile STI Timer Driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Emma Mobile Timer Support - STI
	*
	* Copyright (C) 2012 Magnus Damm
	*
	* 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
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/spinlock.h>
	#include <linux/interrupt.h>
	#include <linux/ioport.h>
	#include <linux/io.h>
	#include <linux/clk.h>
	#include <linux/irq.h>
	#include <linux/err.h>
	#include <linux/delay.h>
	#include <linux/clocksource.h>
	#include <linux/clockchips.h>
	#include <linux/slab.h>
	#include <linux/module.h>

	enum { USER_CLOCKSOURCE, USER_CLOCKEVENT, USER_NR };

	struct em_sti_priv {
	void __iomem *base;
	struct clk *clk;
	struct platform_device *pdev;
	unsigned int active[USER_NR];
	unsigned long rate;
	raw_spinlock_t lock;
	struct clock_event_device ced;
	struct clocksource cs;
	};

	#define STI_CONTROL 0x00
	#define STI_COMPA_H 0x10
	#define STI_COMPA_L 0x14
	#define STI_COMPB_H 0x18
	#define STI_COMPB_L 0x1c
	#define STI_COUNT_H 0x20
	#define STI_COUNT_L 0x24
	#define STI_COUNT_RAW_H 0x28
	#define STI_COUNT_RAW_L 0x2c
	#define STI_SET_H 0x30
	#define STI_SET_L 0x34
	#define STI_INTSTATUS 0x40
	#define STI_INTRAWSTATUS 0x44
	#define STI_INTENSET 0x48
	#define STI_INTENCLR 0x4c
	#define STI_INTFFCLR 0x50

	static inline unsigned long em_sti_read(struct em_sti_priv *p, int offs)
	{
	return ioread32(p->base + offs);
	}

	static inline void em_sti_write(struct em_sti_priv *p, int offs,
	unsigned long value)
	{
	iowrite32(value, p->base + offs);
	}

	static int em_sti_enable(struct em_sti_priv *p)
	{
	int ret;

	/* enable clock */
	ret = clk_enable(p->clk);
	if (ret) {
	dev_err(&p->pdev->dev, "cannot enable clock\n");
	return ret;
	}

	/* configure channel, periodic mode and maximum timeout */
	p->rate = clk_get_rate(p->clk);

	/* reset the counter */
	em_sti_write(p, STI_SET_H, 0x40000000);
	em_sti_write(p, STI_SET_L, 0x00000000);

	/* mask and clear pending interrupts */
	em_sti_write(p, STI_INTENCLR, 3);
	em_sti_write(p, STI_INTFFCLR, 3);

	/* enable updates of counter registers */
	em_sti_write(p, STI_CONTROL, 1);

	return 0;
	}

	static void em_sti_disable(struct em_sti_priv *p)
	{
	/* mask interrupts */
	em_sti_write(p, STI_INTENCLR, 3);

	/* stop clock */
	clk_disable(p->clk);
	}

	static cycle_t em_sti_count(struct em_sti_priv *p)
	{
	cycle_t ticks;
	unsigned long flags;

	/* the STI hardware buffers the 48-bit count, but to
	* break it out into two 32-bit access the registers
	* must be accessed in a certain order.
	* Always read STI_COUNT_H before STI_COUNT_L.
	*/
	raw_spin_lock_irqsave(&p->lock, flags);
	ticks = (cycle_t)(em_sti_read(p, STI_COUNT_H) & 0xffff) << 32;
	ticks \|= em_sti_read(p, STI_COUNT_L);
	raw_spin_unlock_irqrestore(&p->lock, flags);

	return ticks;
	}

	static cycle_t em_sti_set_next(struct em_sti_priv *p, cycle_t next)
	{
	unsigned long flags;

	raw_spin_lock_irqsave(&p->lock, flags);

	/* mask compare A interrupt */
	em_sti_write(p, STI_INTENCLR, 1);

	/* update compare A value */
	em_sti_write(p, STI_COMPA_H, next >> 32);
	em_sti_write(p, STI_COMPA_L, next & 0xffffffff);

	/* clear compare A interrupt source */
	em_sti_write(p, STI_INTFFCLR, 1);

	/* unmask compare A interrupt */
	em_sti_write(p, STI_INTENSET, 1);

	raw_spin_unlock_irqrestore(&p->lock, flags);

	return next;
	}

	static irqreturn_t em_sti_interrupt(int irq, void *dev_id)
	{
	struct em_sti_priv *p = dev_id;

	p->ced.event_handler(&p->ced);
	return IRQ_HANDLED;
	}

	static int em_sti_start(struct em_sti_priv *p, unsigned int user)
	{
	unsigned long flags;
	int used_before;
	int ret = 0;

	raw_spin_lock_irqsave(&p->lock, flags);
	used_before = p->active[USER_CLOCKSOURCE] \| p->active[USER_CLOCKEVENT];
	if (!used_before)
	ret = em_sti_enable(p);

	if (!ret)
	p->active[user] = 1;
	raw_spin_unlock_irqrestore(&p->lock, flags);

	return ret;
	}

	static void em_sti_stop(struct em_sti_priv *p, unsigned int user)
	{
	unsigned long flags;
	int used_before, used_after;

	raw_spin_lock_irqsave(&p->lock, flags);
	used_before = p->active[USER_CLOCKSOURCE] \| p->active[USER_CLOCKEVENT];
	p->active[user] = 0;
	used_after = p->active[USER_CLOCKSOURCE] \| p->active[USER_CLOCKEVENT];

	if (used_before && !used_after)
	em_sti_disable(p);
	raw_spin_unlock_irqrestore(&p->lock, flags);
	}

	static struct em_sti_priv cs_to_em_sti(struct clocksource cs)
	{
	return container_of(cs, struct em_sti_priv, cs);
	}

	static cycle_t em_sti_clocksource_read(struct clocksource *cs)
	{
	return em_sti_count(cs_to_em_sti(cs));
	}

	static int em_sti_clocksource_enable(struct clocksource *cs)
	{
	int ret;
	struct em_sti_priv *p = cs_to_em_sti(cs);

	ret = em_sti_start(p, USER_CLOCKSOURCE);
	if (!ret)
	__clocksource_updatefreq_hz(cs, p->rate);
	return ret;
	}

	static void em_sti_clocksource_disable(struct clocksource *cs)
	{
	em_sti_stop(cs_to_em_sti(cs), USER_CLOCKSOURCE);
	}

	static void em_sti_clocksource_resume(struct clocksource *cs)
	{
	em_sti_clocksource_enable(cs);
	}

	static int em_sti_register_clocksource(struct em_sti_priv *p)
	{
	struct clocksource *cs = &p->cs;

	memset(cs, 0, sizeof(*cs));
	cs->name = dev_name(&p->pdev->dev);
	cs->rating = 200;
	cs->read = em_sti_clocksource_read;
	cs->enable = em_sti_clocksource_enable;
	cs->disable = em_sti_clocksource_disable;
	cs->suspend = em_sti_clocksource_disable;
	cs->resume = em_sti_clocksource_resume;
	cs->mask = CLOCKSOURCE_MASK(48);
	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;

	dev_info(&p->pdev->dev, "used as clock source\n");

	/* Register with dummy 1 Hz value, gets updated in ->enable() */
	clocksource_register_hz(cs, 1);
	return 0;
	}

	static struct em_sti_priv ced_to_em_sti(struct clock_event_device ced)
	{
	return container_of(ced, struct em_sti_priv, ced);
	}

	static void em_sti_clock_event_mode(enum clock_event_mode mode,
	struct clock_event_device *ced)
	{
	struct em_sti_priv *p = ced_to_em_sti(ced);

	/* deal with old setting first */
	switch (ced->mode) {
	case CLOCK_EVT_MODE_ONESHOT:
	em_sti_stop(p, USER_CLOCKEVENT);
	break;
	default:
	break;
	}

	switch (mode) {
	case CLOCK_EVT_MODE_ONESHOT:
	dev_info(&p->pdev->dev, "used for oneshot clock events\n");
	em_sti_start(p, USER_CLOCKEVENT);
	clockevents_config(&p->ced, p->rate);
	break;
	case CLOCK_EVT_MODE_SHUTDOWN:
	case CLOCK_EVT_MODE_UNUSED:
	em_sti_stop(p, USER_CLOCKEVENT);
	break;
	default:
	break;
	}
	}

	static int em_sti_clock_event_next(unsigned long delta,
	struct clock_event_device *ced)
	{
	struct em_sti_priv *p = ced_to_em_sti(ced);
	cycle_t next;
	int safe;

	next = em_sti_set_next(p, em_sti_count(p) + delta);
	safe = em_sti_count(p) < (next - 1);

	return !safe;
	}

	static void em_sti_register_clockevent(struct em_sti_priv *p)
	{
	struct clock_event_device *ced = &p->ced;

	memset(ced, 0, sizeof(*ced));
	ced->name = dev_name(&p->pdev->dev);
	ced->features = CLOCK_EVT_FEAT_ONESHOT;
	ced->rating = 200;
	ced->cpumask = cpumask_of(0);
	ced->set_next_event = em_sti_clock_event_next;
	ced->set_mode = em_sti_clock_event_mode;

	dev_info(&p->pdev->dev, "used for clock events\n");

	/* Register with dummy 1 Hz value, gets updated in ->set_mode() */
	clockevents_config_and_register(ced, 1, 2, 0xffffffff);
	}

	static int em_sti_probe(struct platform_device *pdev)
	{
	struct em_sti_priv *p;
	struct resource *res;
	int irq;

	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
	if (p == NULL) {
	dev_err(&pdev->dev, "failed to allocate driver data\n");
	return -ENOMEM;
	}

	p->pdev = pdev;
	platform_set_drvdata(pdev, p);

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
	dev_err(&pdev->dev, "failed to get irq\n");
	return -EINVAL;
	}

	/* map memory, let base point to the STI instance */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	p->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(p->base))
	return PTR_ERR(p->base);

	/* get hold of clock */
	p->clk = devm_clk_get(&pdev->dev, "sclk");
	if (IS_ERR(p->clk)) {
	dev_err(&pdev->dev, "cannot get clock\n");
	return PTR_ERR(p->clk);
	}

	if (devm_request_irq(&pdev->dev, irq, em_sti_interrupt,
	IRQF_TIMER \| IRQF_IRQPOLL \| IRQF_NOBALANCING,
	dev_name(&pdev->dev), p)) {
	dev_err(&pdev->dev, "failed to request low IRQ\n");
	return -ENOENT;
	}

	raw_spin_lock_init(&p->lock);
	em_sti_register_clockevent(p);
	em_sti_register_clocksource(p);
	return 0;
	}

	static int em_sti_remove(struct platform_device *pdev)
	{
	return -EBUSY; /* cannot unregister clockevent and clocksource */
	}

	static const struct of_device_id em_sti_dt_ids[] = {
	{ .compatible = "renesas,em-sti", },
	{},
	};
	MODULE_DEVICE_TABLE(of, em_sti_dt_ids);

	static struct platform_driver em_sti_device_driver = {
	.probe = em_sti_probe,
	.remove = em_sti_remove,
	.driver = {
	.name = "em_sti",
	.of_match_table = em_sti_dt_ids,
	}
	};

	static int __init em_sti_init(void)
	{
	return platform_driver_register(&em_sti_device_driver);
	}

	static void __exit em_sti_exit(void)
	{
	platform_driver_unregister(&em_sti_device_driver);
	}

	subsys_initcall(em_sti_init);
	module_exit(em_sti_exit);

	MODULE_AUTHOR("Magnus Damm");
	MODULE_DESCRIPTION("Renesas Emma Mobile STI Timer Driver");
	MODULE_LICENSE("GPL v2");