1 files changed, 411 insertions, 302 deletions

diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 75a847dd776a..de7896fd9b33 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -3,6 +3,12 @@
  *
  * OMAP Dual-Mode Timers
  *
+ * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
+ * Tarun Kanti DebBarma <tarun.kanti@ti.com>
+ * Thara Gopinath <thara@ti.com>
+ *
+ * dmtimer adaptation to platform_driver.
+ *
  * Copyright (C) 2005 Nokia Corporation
  * OMAP2 support by Juha Yrjola
  * API improvements and OMAP2 clock framework support by Timo Teras
@@ -29,168 +35,80 @@
  * 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/init.h>
-#include <linux/spinlock.h>
-#include <linux/errno.h>
-#include <linux/list.h>
-#include <linux/clk.h>
-#include <linux/delay.h>
 #include <linux/io.h>
-#include <linux/module.h>
-#include <mach/hardware.h>
-#include <plat/dmtimer.h>
-#include <mach/irqs.h>
-
-static int dm_timer_count;
-
-#ifdef CONFIG_ARCH_OMAP1
-static struct omap_dm_timer omap1_dm_timers[] = {
-	{ .phys_base = 0xfffb1400, .irq = INT_1610_GPTIMER1 },
-	{ .phys_base = 0xfffb1c00, .irq = INT_1610_GPTIMER2 },
-	{ .phys_base = 0xfffb2400, .irq = INT_1610_GPTIMER3 },
-	{ .phys_base = 0xfffb2c00, .irq = INT_1610_GPTIMER4 },
-	{ .phys_base = 0xfffb3400, .irq = INT_1610_GPTIMER5 },
-	{ .phys_base = 0xfffb3c00, .irq = INT_1610_GPTIMER6 },
-	{ .phys_base = 0xfffb7400, .irq = INT_1610_GPTIMER7 },
-	{ .phys_base = 0xfffbd400, .irq = INT_1610_GPTIMER8 },
-};
-
-static const int omap1_dm_timer_count = ARRAY_SIZE(omap1_dm_timers);
-
-#else
-#define omap1_dm_timers			NULL
-#define omap1_dm_timer_count		0
-#endif	/* CONFIG_ARCH_OMAP1 */
-
-#ifdef CONFIG_ARCH_OMAP2
-static struct omap_dm_timer omap2_dm_timers[] = {
-	{ .phys_base = 0x48028000, .irq = INT_24XX_GPTIMER1 },
-	{ .phys_base = 0x4802a000, .irq = INT_24XX_GPTIMER2 },
-	{ .phys_base = 0x48078000, .irq = INT_24XX_GPTIMER3 },
-	{ .phys_base = 0x4807a000, .irq = INT_24XX_GPTIMER4 },
-	{ .phys_base = 0x4807c000, .irq = INT_24XX_GPTIMER5 },
-	{ .phys_base = 0x4807e000, .irq = INT_24XX_GPTIMER6 },
-	{ .phys_base = 0x48080000, .irq = INT_24XX_GPTIMER7 },
-	{ .phys_base = 0x48082000, .irq = INT_24XX_GPTIMER8 },
-	{ .phys_base = 0x48084000, .irq = INT_24XX_GPTIMER9 },
-	{ .phys_base = 0x48086000, .irq = INT_24XX_GPTIMER10 },
-	{ .phys_base = 0x48088000, .irq = INT_24XX_GPTIMER11 },
-	{ .phys_base = 0x4808a000, .irq = INT_24XX_GPTIMER12 },
-};
-
-static const char *omap2_dm_source_names[] __initdata = {
-	"sys_ck",
-	"func_32k_ck",
-	"alt_ck",
-	NULL
-};
-
-static struct clk *omap2_dm_source_clocks[3];
-static const int omap2_dm_timer_count = ARRAY_SIZE(omap2_dm_timers);
-
-#else
-#define omap2_dm_timers			NULL
-#define omap2_dm_timer_count		0
-#define omap2_dm_source_names		NULL
-#define omap2_dm_source_clocks		NULL
-#endif	/* CONFIG_ARCH_OMAP2 */
-
-#ifdef CONFIG_ARCH_OMAP3
-static struct omap_dm_timer omap3_dm_timers[] = {
-	{ .phys_base = 0x48318000, .irq = INT_24XX_GPTIMER1 },
-	{ .phys_base = 0x49032000, .irq = INT_24XX_GPTIMER2 },
-	{ .phys_base = 0x49034000, .irq = INT_24XX_GPTIMER3 },
-	{ .phys_base = 0x49036000, .irq = INT_24XX_GPTIMER4 },
-	{ .phys_base = 0x49038000, .irq = INT_24XX_GPTIMER5 },
-	{ .phys_base = 0x4903A000, .irq = INT_24XX_GPTIMER6 },
-	{ .phys_base = 0x4903C000, .irq = INT_24XX_GPTIMER7 },
-	{ .phys_base = 0x4903E000, .irq = INT_24XX_GPTIMER8 },
-	{ .phys_base = 0x49040000, .irq = INT_24XX_GPTIMER9 },
-	{ .phys_base = 0x48086000, .irq = INT_24XX_GPTIMER10 },
-	{ .phys_base = 0x48088000, .irq = INT_24XX_GPTIMER11 },
-	{ .phys_base = 0x48304000, .irq = INT_34XX_GPT12_IRQ },
-};
-
-static const char *omap3_dm_source_names[] __initdata = {
-	"sys_ck",
-	"omap_32k_fck",
-	NULL
-};
-
-static struct clk *omap3_dm_source_clocks[2];
-static const int omap3_dm_timer_count = ARRAY_SIZE(omap3_dm_timers);
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/pm_runtime.h>
 
-#else
-#define omap3_dm_timers			NULL
-#define omap3_dm_timer_count		0
-#define omap3_dm_source_names		NULL
-#define omap3_dm_source_clocks		NULL
-#endif	/* CONFIG_ARCH_OMAP3 */
-
-#ifdef CONFIG_ARCH_OMAP4
-static struct omap_dm_timer omap4_dm_timers[] = {
-	{ .phys_base = 0x4a318000, .irq = OMAP44XX_IRQ_GPT1 },
-	{ .phys_base = 0x48032000, .irq = OMAP44XX_IRQ_GPT2 },
-	{ .phys_base = 0x48034000, .irq = OMAP44XX_IRQ_GPT3 },
-	{ .phys_base = 0x48036000, .irq = OMAP44XX_IRQ_GPT4 },
-	{ .phys_base = 0x40138000, .irq = OMAP44XX_IRQ_GPT5 },
-	{ .phys_base = 0x4013a000, .irq = OMAP44XX_IRQ_GPT6 },
-	{ .phys_base = 0x4013a000, .irq = OMAP44XX_IRQ_GPT7 },
-	{ .phys_base = 0x4013e000, .irq = OMAP44XX_IRQ_GPT8 },
-	{ .phys_base = 0x4803e000, .irq = OMAP44XX_IRQ_GPT9 },
-	{ .phys_base = 0x48086000, .irq = OMAP44XX_IRQ_GPT10 },
-	{ .phys_base = 0x48088000, .irq = OMAP44XX_IRQ_GPT11 },
-	{ .phys_base = 0x4a320000, .irq = OMAP44XX_IRQ_GPT12 },
-};
-static const char *omap4_dm_source_names[] __initdata = {
-	"sys_clkin_ck",
-	"sys_32k_ck",
-	NULL
-};
-static struct clk *omap4_dm_source_clocks[2];
-static const int omap4_dm_timer_count = ARRAY_SIZE(omap4_dm_timers);
-
-#else
-#define omap4_dm_timers			NULL
-#define omap4_dm_timer_count		0
-#define omap4_dm_source_names		NULL
-#define omap4_dm_source_clocks		NULL
-#endif	/* CONFIG_ARCH_OMAP4 */
-
-static struct omap_dm_timer *dm_timers;
-static const char **dm_source_names;
-static struct clk **dm_source_clocks;
+#include <plat/dmtimer.h>
 
-static spinlock_t dm_timer_lock;
+static LIST_HEAD(omap_timer_list);
+static DEFINE_SPINLOCK(dm_timer_lock);
 
-/*
- * Reads timer registers in posted and non-posted mode. The posted mode bit
- * is encoded in reg. Note that in posted mode write pending bit must be
- * checked. Otherwise a read of a non completed write will produce an error.
+/**
+ * omap_dm_timer_read_reg - read timer registers in posted and non-posted mode
+ * @timer:      timer pointer over which read operation to perform
+ * @reg:        lowest byte holds the register offset
+ *
+ * The posted mode bit is encoded in reg. Note that in posted mode write
+ * pending bit must be checked. Otherwise a read of a non completed write
+ * will produce an error.
  */
 static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
 {
-	return __omap_dm_timer_read(timer->io_base, reg, timer->posted);
+	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
+	return __omap_dm_timer_read(timer, reg, timer->posted);
 }
 
-/*
- * Writes timer registers in posted and non-posted mode. The posted mode bit
- * is encoded in reg. Note that in posted mode the write pending bit must be
- * checked. Otherwise a write on a register which has a pending write will be
- * lost.
+/**
+ * omap_dm_timer_write_reg - write timer registers in posted and non-posted mode
+ * @timer:      timer pointer over which write operation is to perform
+ * @reg:        lowest byte holds the register offset
+ * @value:      data to write into the register
+ *
+ * The posted mode bit is encoded in reg. Note that in posted mode the write
+ * pending bit must be checked. Otherwise a write on a register which has a
+ * pending write will be lost.
  */
 static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
 						u32 value)
 {
-	__omap_dm_timer_write(timer->io_base, reg, value, timer->posted);
+	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
+	__omap_dm_timer_write(timer, reg, value, timer->posted);
+}
+
+static void omap_timer_restore_context(struct omap_dm_timer *timer)
+{
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_OCP_CFG_OFFSET,
+				timer->context.tiocp_cfg);
+	if (timer->revision > 1)
+		__raw_writel(timer->context.tistat, timer->sys_stat);
+
+	__raw_writel(timer->context.tisr, timer->irq_stat);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
+				timer->context.twer);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
+				timer->context.tcrr);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG,
+				timer->context.tldr);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG,
+				timer->context.tmar);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG,
+				timer->context.tsicr);
+	__raw_writel(timer->context.tier, timer->irq_ena);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG,
+				timer->context.tclr);
 }
 
 static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
 {
 	int c;
 
+	if (!timer->sys_stat)
+		return;
+
 	c = 0;
-	while (!(omap_dm_timer_read_reg(timer, OMAP_TIMER_SYS_STAT_REG) & 1)) {
+	while (!(__raw_readl(timer->sys_stat) & 1)) {
 		c++;
 		if (c > 100000) {
 			printk(KERN_ERR "Timer failed to reset\n");
@@ -201,53 +119,65 @@ static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
 
 static void omap_dm_timer_reset(struct omap_dm_timer *timer)
 {
-	int autoidle = 0, wakeup = 0;
-
-	if (!cpu_class_is_omap2() || timer != &dm_timers[0]) {
+	omap_dm_timer_enable(timer);
+	if (timer->pdev->id != 1) {
 		omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
 		omap_dm_timer_wait_for_reset(timer);
 	}
-	omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
-
-	/* Enable autoidle on OMAP2+ */
-	if (cpu_class_is_omap2())
-		autoidle = 1;
-
-	/*
-	 * Enable wake-up on OMAP2 CPUs.
-	 */
-	if (cpu_class_is_omap2())
-		wakeup = 1;
 
-	__omap_dm_timer_reset(timer->io_base, autoidle, wakeup);
+	__omap_dm_timer_reset(timer, 0, 0);
+	omap_dm_timer_disable(timer);
 	timer->posted = 1;
 }
 
-void omap_dm_timer_prepare(struct omap_dm_timer *timer)
+int omap_dm_timer_prepare(struct omap_dm_timer *timer)
 {
-	omap_dm_timer_enable(timer);
-	omap_dm_timer_reset(timer);
+	struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
+	int ret;
+
+	timer->fclk = clk_get(&timer->pdev->dev, "fck");
+	if (WARN_ON_ONCE(IS_ERR_OR_NULL(timer->fclk))) {
+		timer->fclk = NULL;
+		dev_err(&timer->pdev->dev, ": No fclk handle.\n");
+		return -EINVAL;
+	}
+
+	if (pdata->needs_manual_reset)
+		omap_dm_timer_reset(timer);
+
+	ret = omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
+
+	timer->posted = 1;
+	return ret;
 }
 
 struct omap_dm_timer *omap_dm_timer_request(void)
 {
-	struct omap_dm_timer *timer = NULL;
+	struct omap_dm_timer *timer = NULL, *t;
 	unsigned long flags;
-	int i;
+	int ret = 0;
 
 	spin_lock_irqsave(&dm_timer_lock, flags);
-	for (i = 0; i < dm_timer_count; i++) {
-		if (dm_timers[i].reserved)
+	list_for_each_entry(t, &omap_timer_list, node) {
+		if (t->reserved)
 			continue;
 
-		timer = &dm_timers[i];
+		timer = t;
 		timer->reserved = 1;
 		break;
 	}
+
+	if (timer) {
+		ret = omap_dm_timer_prepare(timer);
+		if (ret) {
+			timer->reserved = 0;
+			timer = NULL;
+		}
+	}
 	spin_unlock_irqrestore(&dm_timer_lock, flags);
 
-	if (timer != NULL)
-		omap_dm_timer_prepare(timer);
+	if (!timer)
+		pr_debug("%s: timer request failed!\n", __func__);
 
 	return timer;
 }
@@ -255,74 +185,65 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_request);
 
 struct omap_dm_timer *omap_dm_timer_request_specific(int id)
 {
-	struct omap_dm_timer *timer;
+	struct omap_dm_timer *timer = NULL, *t;
 	unsigned long flags;
+	int ret = 0;
 
 	spin_lock_irqsave(&dm_timer_lock, flags);
-	if (id <= 0 || id > dm_timer_count || dm_timers[id-1].reserved) {
-		spin_unlock_irqrestore(&dm_timer_lock, flags);
-		printk("BUG: warning at %s:%d/%s(): unable to get timer %d\n",
-		       __FILE__, __LINE__, __func__, id);
-		dump_stack();
-		return NULL;
+	list_for_each_entry(t, &omap_timer_list, node) {
+		if (t->pdev->id == id && !t->reserved) {
+			timer = t;
+			timer->reserved = 1;
+			break;
+		}
 	}
 
-	timer = &dm_timers[id-1];
-	timer->reserved = 1;
+	if (timer) {
+		ret = omap_dm_timer_prepare(timer);
+		if (ret) {
+			timer->reserved = 0;
+			timer = NULL;
+		}
+	}
 	spin_unlock_irqrestore(&dm_timer_lock, flags);
 
-	omap_dm_timer_prepare(timer);
+	if (!timer)
+		pr_debug("%s: timer%d request failed!\n", __func__, id);
 
 	return timer;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific);
 
-void omap_dm_timer_free(struct omap_dm_timer *timer)
+int omap_dm_timer_free(struct omap_dm_timer *timer)
 {
-	omap_dm_timer_enable(timer);
-	omap_dm_timer_reset(timer);
-	omap_dm_timer_disable(timer);
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	clk_put(timer->fclk);
 
 	WARN_ON(!timer->reserved);
 	timer->reserved = 0;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_free);
 
 void omap_dm_timer_enable(struct omap_dm_timer *timer)
 {
-	if (timer->enabled)
-		return;
-
-#ifdef CONFIG_ARCH_OMAP2PLUS
-	if (cpu_class_is_omap2()) {
-		clk_enable(timer->fclk);
-		clk_enable(timer->iclk);
-	}
-#endif
-
-	timer->enabled = 1;
+	pm_runtime_get_sync(&timer->pdev->dev);
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_enable);
 
 void omap_dm_timer_disable(struct omap_dm_timer *timer)
 {
-	if (!timer->enabled)
-		return;
-
-#ifdef CONFIG_ARCH_OMAP2PLUS
-	if (cpu_class_is_omap2()) {
-		clk_disable(timer->iclk);
-		clk_disable(timer->fclk);
-	}
-#endif
-
-	timer->enabled = 0;
+	pm_runtime_put(&timer->pdev->dev);
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_disable);
 
 int omap_dm_timer_get_irq(struct omap_dm_timer *timer)
 {
-	return timer->irq;
+	if (timer)
+		return timer->irq;
+	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_get_irq);
 
@@ -334,24 +255,29 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_get_irq);
  */
 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
 {
-	int i;
+	int i = 0;
+	struct omap_dm_timer *timer = NULL;
+	unsigned long flags;
 
 	/* If ARMXOR cannot be idled this function call is unnecessary */
 	if (!(inputmask & (1 << 1)))
 		return inputmask;
 
 	/* If any active timer is using ARMXOR return modified mask */
-	for (i = 0; i < dm_timer_count; i++) {
+	spin_lock_irqsave(&dm_timer_lock, flags);
+	list_for_each_entry(timer, &omap_timer_list, node) {
 		u32 l;
 
-		l = omap_dm_timer_read_reg(&dm_timers[i], OMAP_TIMER_CTRL_REG);
+		l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 		if (l & OMAP_TIMER_CTRL_ST) {
 			if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
 				inputmask &= ~(1 << 1);
 			else
 				inputmask &= ~(1 << 2);
 		}
+		i++;
 	}
+	spin_unlock_irqrestore(&dm_timer_lock, flags);
 
 	return inputmask;
 }
@@ -361,7 +287,9 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);
 
 struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *timer)
 {
-	return timer->fclk;
+	if (timer)
+		return timer->fclk;
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_get_fclk);
 
@@ -375,70 +303,91 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);
 
 #endif
 
-void omap_dm_timer_trigger(struct omap_dm_timer *timer)
+int omap_dm_timer_trigger(struct omap_dm_timer *timer)
 {
+	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
+		pr_err("%s: timer not available or enabled.\n", __func__);
+		return -EINVAL;
+	}
+
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_trigger);
 
-void omap_dm_timer_start(struct omap_dm_timer *timer)
+int omap_dm_timer_start(struct omap_dm_timer *timer)
 {
 	u32 l;
 
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
+
+	if (timer->loses_context) {
+		u32 ctx_loss_cnt_after =
+			timer->get_context_loss_count(&timer->pdev->dev);
+		if (ctx_loss_cnt_after != timer->ctx_loss_count)
+			omap_timer_restore_context(timer);
+	}
+
 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 	if (!(l & OMAP_TIMER_CTRL_ST)) {
 		l |= OMAP_TIMER_CTRL_ST;
 		omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
 	}
+
+	/* Save the context */
+	timer->context.tclr = l;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_start);
 
-void omap_dm_timer_stop(struct omap_dm_timer *timer)
+int omap_dm_timer_stop(struct omap_dm_timer *timer)
 {
 	unsigned long rate = 0;
+	struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
 
-#ifdef CONFIG_ARCH_OMAP2PLUS
-	rate = clk_get_rate(timer->fclk);
-#endif
+	if (unlikely(!timer))
+		return -EINVAL;
 
-	__omap_dm_timer_stop(timer->io_base, timer->posted, rate);
+	if (!pdata->needs_manual_reset)
+		rate = clk_get_rate(timer->fclk);
+
+	__omap_dm_timer_stop(timer, timer->posted, rate);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_stop);
 
-#ifdef CONFIG_ARCH_OMAP1
-
 int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
 {
-	int n = (timer - dm_timers) << 1;
-	u32 l;
-
-	l = omap_readl(MOD_CONF_CTRL_1) & ~(0x03 << n);
-	l |= source << n;
-	omap_writel(l, MOD_CONF_CTRL_1);
+	int ret;
+	struct dmtimer_platform_data *pdata;
 
-	return 0;
-}
-EXPORT_SYMBOL_GPL(omap_dm_timer_set_source);
+	if (unlikely(!timer))
+		return -EINVAL;
 
-#else
+	pdata = timer->pdev->dev.platform_data;
 
-int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
-{
 	if (source < 0 || source >= 3)
 		return -EINVAL;
 
-	return __omap_dm_timer_set_source(timer->fclk,
-						dm_source_clocks[source]);
+	ret = pdata->set_timer_src(timer->pdev, source);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_source);
 
-#endif
-
-void omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
+int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
 			    unsigned int load)
 {
 	u32 l;
 
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 	if (autoreload)
 		l |= OMAP_TIMER_CTRL_AR;
@@ -448,15 +397,32 @@ void omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
 
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
+	/* Save the context */
+	timer->context.tclr = l;
+	timer->context.tldr = load;
+	omap_dm_timer_disable(timer);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_load);
 
 /* Optimized set_load which removes costly spin wait in timer_start */
-void omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
+int omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
                             unsigned int load)
 {
 	u32 l;
 
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
+
+	if (timer->loses_context) {
+		u32 ctx_loss_cnt_after =
+			timer->get_context_loss_count(&timer->pdev->dev);
+		if (ctx_loss_cnt_after != timer->ctx_loss_count)
+			omap_timer_restore_context(timer);
+	}
+
 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 	if (autoreload) {
 		l |= OMAP_TIMER_CTRL_AR;
@@ -466,15 +432,25 @@ void omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
 	}
 	l |= OMAP_TIMER_CTRL_ST;
 
-	__omap_dm_timer_load_start(timer->io_base, l, load, timer->posted);
+	__omap_dm_timer_load_start(timer, l, load, timer->posted);
+
+	/* Save the context */
+	timer->context.tclr = l;
+	timer->context.tldr = load;
+	timer->context.tcrr = load;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_load_start);
 
-void omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
+int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
 			     unsigned int match)
 {
 	u32 l;
 
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 	if (enable)
 		l |= OMAP_TIMER_CTRL_CE;
@@ -482,14 +458,24 @@ void omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
 		l &= ~OMAP_TIMER_CTRL_CE;
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);
+
+	/* Save the context */
+	timer->context.tclr = l;
+	timer->context.tmar = match;
+	omap_dm_timer_disable(timer);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_match);
 
-void omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
+int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
 			   int toggle, int trigger)
 {
 	u32 l;
 
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 	l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
 	       OMAP_TIMER_CTRL_PT | (0x03 << 10));
@@ -499,13 +485,22 @@ void omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
 		l |= OMAP_TIMER_CTRL_PT;
 	l |= trigger << 10;
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
+
+	/* Save the context */
+	timer->context.tclr = l;
+	omap_dm_timer_disable(timer);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm);
 
-void omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
+int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
 {
 	u32 l;
 
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
 	l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
 	if (prescaler >= 0x00 && prescaler <= 0x07) {
@@ -513,13 +508,28 @@ void omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
 		l |= prescaler << 2;
 	}
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
+
+	/* Save the context */
+	timer->context.tclr = l;
+	omap_dm_timer_disable(timer);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler);
 
-void omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
+int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
 				  unsigned int value)
 {
-	__omap_dm_timer_int_enable(timer->io_base, value);
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
+	__omap_dm_timer_int_enable(timer, value);
+
+	/* Save the context */
+	timer->context.tier = value;
+	timer->context.twer = value;
+	omap_dm_timer_disable(timer);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable);
 
@@ -527,40 +537,61 @@ unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
 {
 	unsigned int l;
 
-	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_STAT_REG);
+	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
+		pr_err("%s: timer not available or enabled.\n", __func__);
+		return 0;
+	}
+
+	l = __raw_readl(timer->irq_stat);
 
 	return l;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_read_status);
 
-void omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
+int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
 {
-	__omap_dm_timer_write_status(timer->io_base, value);
+	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev)))
+		return -EINVAL;
+
+	__omap_dm_timer_write_status(timer, value);
+	/* Save the context */
+	timer->context.tisr = value;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_write_status);
 
 unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
 {
-	return __omap_dm_timer_read_counter(timer->io_base, timer->posted);
+	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
+		pr_err("%s: timer not iavailable or enabled.\n", __func__);
+		return 0;
+	}
+
+	return __omap_dm_timer_read_counter(timer, timer->posted);
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_read_counter);
 
-void omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
+int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
 {
+	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
+		pr_err("%s: timer not available or enabled.\n", __func__);
+		return -EINVAL;
+	}
+
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG, value);
+
+	/* Save the context */
+	timer->context.tcrr = value;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_write_counter);
 
 int omap_dm_timers_active(void)
 {
-	int i;
-
-	for (i = 0; i < dm_timer_count; i++) {
-		struct omap_dm_timer *timer;
-
-		timer = &dm_timers[i];
+	struct omap_dm_timer *timer;
 
-		if (!timer->enabled)
+	list_for_each_entry(timer, &omap_timer_list, node) {
+		if (!timer->reserved)
 			continue;
 
 		if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
@@ -572,69 +603,147 @@ int omap_dm_timers_active(void)
 }
 EXPORT_SYMBOL_GPL(omap_dm_timers_active);
 
-static int __init omap_dm_timer_init(void)
+/**
+ * omap_dm_timer_probe - probe function called for every registered device
+ * @pdev:	pointer to current timer platform device
+ *
+ * Called by driver framework at the end of device registration for all
+ * timer devices.
+ */
+static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
 {
+	int ret;
+	unsigned long flags;
 	struct omap_dm_timer *timer;
-	int i, map_size = SZ_8K;	/* Module 4KB + L4 4KB except on omap1 */
+	struct resource *mem, *irq, *ioarea;
+	struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
 
-	if (!(cpu_is_omap16xx() || cpu_class_is_omap2()))
+	if (!pdata) {
+		dev_err(&pdev->dev, "%s: no platform data.\n", __func__);
 		return -ENODEV;
+	}
 
-	spin_lock_init(&dm_timer_lock);
-
-	if (cpu_class_is_omap1()) {
-		dm_timers = omap1_dm_timers;
-		dm_timer_count = omap1_dm_timer_count;
-		map_size = SZ_2K;
-	} else if (cpu_is_omap24xx()) {
-		dm_timers = omap2_dm_timers;
-		dm_timer_count = omap2_dm_timer_count;
-		dm_source_names = omap2_dm_source_names;
-		dm_source_clocks = omap2_dm_source_clocks;
-	} else if (cpu_is_omap34xx()) {
-		dm_timers = omap3_dm_timers;
-		dm_timer_count = omap3_dm_timer_count;
-		dm_source_names = omap3_dm_source_names;
-		dm_source_clocks = omap3_dm_source_clocks;
-	} else if (cpu_is_omap44xx()) {
-		dm_timers = omap4_dm_timers;
-		dm_timer_count = omap4_dm_timer_count;
-		dm_source_names = omap4_dm_source_names;
-		dm_source_clocks = omap4_dm_source_clocks;
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (unlikely(!irq)) {
+		dev_err(&pdev->dev, "%s: no IRQ resource.\n", __func__);
+		return -ENODEV;
 	}
 
-	if (cpu_class_is_omap2())
-		for (i = 0; dm_source_names[i] != NULL; i++)
-			dm_source_clocks[i] = clk_get(NULL, dm_source_names[i]);
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (unlikely(!mem)) {
+		dev_err(&pdev->dev, "%s: no memory resource.\n", __func__);
+		return -ENODEV;
+	}
 
-	if (cpu_is_omap243x())
-		dm_timers[0].phys_base = 0x49018000;
+	ioarea = request_mem_region(mem->start, resource_size(mem),
+			pdev->name);
+	if (!ioarea) {
+		dev_err(&pdev->dev, "%s: region already claimed.\n", __func__);
+		return -EBUSY;
+	}
 
-	for (i = 0; i < dm_timer_count; i++) {
-		timer = &dm_timers[i];
+	timer = kzalloc(sizeof(struct omap_dm_timer), GFP_KERNEL);
+	if (!timer) {
+		dev_err(&pdev->dev, "%s: no memory for omap_dm_timer.\n",
+			__func__);
+		ret = -ENOMEM;
+		goto err_free_ioregion;
+	}
 
-		/* Static mapping, never released */
-		timer->io_base = ioremap(timer->phys_base, map_size);
-		BUG_ON(!timer->io_base);
+	timer->io_base = ioremap(mem->start, resource_size(mem));
+	if (!timer->io_base) {
+		dev_err(&pdev->dev, "%s: ioremap failed.\n", __func__);
+		ret = -ENOMEM;
+		goto err_free_mem;
+	}
 
-#ifdef CONFIG_ARCH_OMAP2PLUS
-		if (cpu_class_is_omap2()) {
-			char clk_name[16];
-			sprintf(clk_name, "gpt%d_ick", i + 1);
-			timer->iclk = clk_get(NULL, clk_name);
-			sprintf(clk_name, "gpt%d_fck", i + 1);
-			timer->fclk = clk_get(NULL, clk_name);
-		}
+	timer->id = pdev->id;
+	timer->irq = irq->start;
+	timer->reserved = pdata->reserved;
+	timer->pdev = pdev;
+	timer->loses_context = pdata->loses_context;
+	timer->get_context_loss_count = pdata->get_context_loss_count;
+
+	/* Skip pm_runtime_enable for OMAP1 */
+	if (!pdata->needs_manual_reset) {
+		pm_runtime_enable(&pdev->dev);
+		pm_runtime_irq_safe(&pdev->dev);
+	}
 
-		/* One or two timers may be set up early for sys_timer */
-		if (sys_timer_reserved & (1  << i)) {
-			timer->reserved = 1;
-			timer->posted = 1;
-		}
-#endif
+	if (!timer->reserved) {
+		pm_runtime_get_sync(&pdev->dev);
+		__omap_dm_timer_init_regs(timer);
+		pm_runtime_put(&pdev->dev);
 	}
 
+	/* add the timer element to the list */
+	spin_lock_irqsave(&dm_timer_lock, flags);
+	list_add_tail(&timer->node, &omap_timer_list);
+	spin_unlock_irqrestore(&dm_timer_lock, flags);
+
+	dev_dbg(&pdev->dev, "Device Probed.\n");
+
 	return 0;
+
+err_free_mem:
+	kfree(timer);
+
+err_free_ioregion:
+	release_mem_region(mem->start, resource_size(mem));
+
+	return ret;
 }
 
-arch_initcall(omap_dm_timer_init);
+/**
+ * omap_dm_timer_remove - cleanup a registered timer device
+ * @pdev:	pointer to current timer platform device
+ *
+ * Called by driver framework whenever a timer device is unregistered.
+ * In addition to freeing platform resources it also deletes the timer
+ * entry from the local list.
+ */
+static int __devexit omap_dm_timer_remove(struct platform_device *pdev)
+{
+	struct omap_dm_timer *timer;
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	spin_lock_irqsave(&dm_timer_lock, flags);
+	list_for_each_entry(timer, &omap_timer_list, node)
+		if (timer->pdev->id == pdev->id) {
+			list_del(&timer->node);
+			kfree(timer);
+			ret = 0;
+			break;
+		}
+	spin_unlock_irqrestore(&dm_timer_lock, flags);
+
+	return ret;
+}
+
+static struct platform_driver omap_dm_timer_driver = {
+	.probe  = omap_dm_timer_probe,
+	.remove = omap_dm_timer_remove,
+	.driver = {
+		.name   = "omap_timer",
+	},
+};
+
+static int __init omap_dm_timer_driver_init(void)
+{
+	return platform_driver_register(&omap_dm_timer_driver);
+}
+
+static void __exit omap_dm_timer_driver_exit(void)
+{
+	platform_driver_unregister(&omap_dm_timer_driver);
+}
+
+early_platform_init("earlytimer", &omap_dm_timer_driver);
+module_init(omap_dm_timer_driver_init);
+module_exit(omap_dm_timer_driver_exit);
+
+MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_AUTHOR("Texas Instruments Inc");