[3/3] OMAP: PM: DMA: Enable runtime pm
diff mbox

Message ID 1298542475-1460-4-git-send-email-manjugk@ti.com
State Changes Requested
Delegated to: Kevin Hilman
Headers show

Commit Message

manjugk manjugk Feb. 24, 2011, 10:14 a.m. UTC
None

Patch
diff mbox

diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index 84879eb..92e18e3 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -35,6 +35,7 @@ 
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
+#include <linux/pm_runtime.h>
 
 #include <asm/system.h>
 #include <mach/hardware.h>
@@ -60,6 +61,7 @@  enum { DMA_CHAIN_STARTED, DMA_CHAIN_NOTSTARTED };
 
 static struct omap_system_dma_plat_info *p;
 static struct omap_dma_dev_attr *d;
+static struct device *dev;
 
 static int enable_1510_mode;
 static u32 errata;
@@ -172,6 +174,7 @@  void omap_set_dma_priority(int lch, int dst_port, int priority)
 	unsigned long reg;
 	u32 l;
 
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap1()) {
 		switch (dst_port) {
 		case OMAP_DMA_PORT_OCP_T1:	/* FFFECC00 */
@@ -188,6 +191,7 @@  void omap_set_dma_priority(int lch, int dst_port, int priority)
 			break;
 		default:
 			BUG();
+			pm_runtime_put_autosuspend(dev);
 			return;
 		}
 		l = omap_readl(reg);
@@ -206,6 +210,7 @@  void omap_set_dma_priority(int lch, int dst_port, int priority)
 			ccr &= ~(1 << 6);
 		p->dma_write(ccr, CCR, lch);
 	}
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_priority);
 
@@ -215,6 +220,8 @@  void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
 {
 	u32 l;
 
+	pm_runtime_get_sync(dev);
+
 	l = p->dma_read(CSDP, lch);
 	l &= ~0x03;
 	l |= data_type;
@@ -269,6 +276,7 @@  void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
 
 	p->dma_write(elem_count, CEN, lch);
 	p->dma_write(frame_count, CFN, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_transfer_params);
 
@@ -276,6 +284,7 @@  void omap_set_dma_color_mode(int lch, enum omap_dma_color_mode mode, u32 color)
 {
 	BUG_ON(omap_dma_in_1510_mode());
 
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap1()) {
 		u16 w;
 
@@ -329,11 +338,13 @@  void omap_set_dma_color_mode(int lch, enum omap_dma_color_mode mode, u32 color)
 		color &= 0xffffff;
 		p->dma_write(color, COLOR, lch);
 	}
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_color_mode);
 
 void omap_set_dma_write_mode(int lch, enum omap_dma_write_mode mode)
 {
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap2()) {
 		u32 csdp;
 
@@ -342,11 +353,13 @@  void omap_set_dma_write_mode(int lch, enum omap_dma_write_mode mode)
 		csdp |= (mode << 16);
 		p->dma_write(csdp, CSDP, lch);
 	}
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_write_mode);
 
 void omap_set_dma_channel_mode(int lch, enum omap_dma_channel_mode mode)
 {
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap1() && !cpu_is_omap15xx()) {
 		u32 l;
 
@@ -355,6 +368,7 @@  void omap_set_dma_channel_mode(int lch, enum omap_dma_channel_mode mode)
 		l |= mode;
 		p->dma_write(l, LCH_CTRL, lch);
 	}
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_channel_mode);
 
@@ -365,6 +379,8 @@  void omap_set_dma_src_params(int lch, int src_port, int src_amode,
 {
 	u32 l;
 
+	pm_runtime_get_sync(dev);
+
 	if (cpu_class_is_omap1()) {
 		u16 w;
 
@@ -383,11 +399,13 @@  void omap_set_dma_src_params(int lch, int src_port, int src_amode,
 
 	p->dma_write(src_ei, CSEI, lch);
 	p->dma_write(src_fi, CSFI, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_src_params);
 
 void omap_set_dma_params(int lch, struct omap_dma_channel_params *params)
 {
+	pm_runtime_get_sync(dev);
 	omap_set_dma_transfer_params(lch, params->data_type,
 				     params->elem_count, params->frame_count,
 				     params->sync_mode, params->trigger,
@@ -402,6 +420,7 @@  void omap_set_dma_params(int lch, struct omap_dma_channel_params *params)
 	if (params->read_prio || params->write_prio)
 		omap_dma_set_prio_lch(lch, params->read_prio,
 				      params->write_prio);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_params);
 
@@ -410,8 +429,10 @@  void omap_set_dma_src_index(int lch, int eidx, int fidx)
 	if (cpu_class_is_omap2())
 		return;
 
+	pm_runtime_get_sync(dev);
 	p->dma_write(eidx, CSEI, lch);
 	p->dma_write(fidx, CSFI, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_src_index);
 
@@ -419,11 +440,13 @@  void omap_set_dma_src_data_pack(int lch, int enable)
 {
 	u32 l;
 
+	pm_runtime_get_sync(dev);
 	l = p->dma_read(CSDP, lch);
 	l &= ~(1 << 6);
 	if (enable)
 		l |= (1 << 6);
 	p->dma_write(l, CSDP, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_src_data_pack);
 
@@ -432,6 +455,7 @@  void omap_set_dma_src_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
 	unsigned int burst = 0;
 	u32 l;
 
+	pm_runtime_get_sync(dev);
 	l = p->dma_read(CSDP, lch);
 	l &= ~(0x03 << 7);
 
@@ -469,6 +493,7 @@  void omap_set_dma_src_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
 
 	l |= (burst << 7);
 	p->dma_write(l, CSDP, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_src_burst_mode);
 
@@ -478,6 +503,7 @@  void omap_set_dma_dest_params(int lch, int dest_port, int dest_amode,
 			      int dst_ei, int dst_fi)
 {
 	u32 l;
+	pm_runtime_get_sync(dev);
 
 	if (cpu_class_is_omap1()) {
 		l = p->dma_read(CSDP, lch);
@@ -495,6 +521,7 @@  void omap_set_dma_dest_params(int lch, int dest_port, int dest_amode,
 
 	p->dma_write(dst_ei, CDEI, lch);
 	p->dma_write(dst_fi, CDFI, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_dest_params);
 
@@ -502,21 +529,25 @@  void omap_set_dma_dest_index(int lch, int eidx, int fidx)
 {
 	if (cpu_class_is_omap2())
 		return;
+	pm_runtime_get_sync(dev);
 
 	p->dma_write(eidx, CDEI, lch);
 	p->dma_write(fidx, CDFI, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_dest_index);
 
 void omap_set_dma_dest_data_pack(int lch, int enable)
 {
 	u32 l;
+	pm_runtime_get_sync(dev);
 
 	l = p->dma_read(CSDP, lch);
 	l &= ~(1 << 13);
 	if (enable)
 		l |= 1 << 13;
 	p->dma_write(l, CSDP, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_dest_data_pack);
 
@@ -524,6 +555,7 @@  void omap_set_dma_dest_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
 {
 	unsigned int burst = 0;
 	u32 l;
+	pm_runtime_get_sync(dev);
 
 	l = p->dma_read(CSDP, lch);
 	l &= ~(0x03 << 14);
@@ -555,10 +587,12 @@  void omap_set_dma_dest_burst_mode(int lch, enum omap_dma_burst_mode burst_mode)
 	default:
 		printk(KERN_ERR "Invalid DMA burst mode\n");
 		BUG();
+		pm_runtime_put_autosuspend(dev);
 		return;
 	}
 	l |= (burst << 14);
 	p->dma_write(l, CSDP, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_set_dma_dest_burst_mode);
 
@@ -566,6 +600,7 @@  static inline void omap_enable_channel_irq(int lch)
 {
 	u32 status;
 
+	pm_runtime_get_sync(dev);
 	/* Clear CSR */
 	if (cpu_class_is_omap1())
 		status = p->dma_read(CSR, lch);
@@ -574,12 +609,15 @@  static inline void omap_enable_channel_irq(int lch)
 
 	/* Enable some nice interrupts. */
 	p->dma_write(dma_chan[lch].enabled_irqs, CICR, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 
 static void omap_disable_channel_irq(int lch)
 {
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap2())
 		p->dma_write(0, CICR, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 
 void omap_enable_dma_irq(int lch, u16 bits)
@@ -597,6 +635,7 @@  EXPORT_SYMBOL(omap_disable_dma_irq);
 static inline void enable_lnk(int lch)
 {
 	u32 l;
+	pm_runtime_get_sync(dev);
 
 	l = p->dma_read(CLNK_CTRL, lch);
 
@@ -614,12 +653,14 @@  static inline void enable_lnk(int lch)
 #endif
 
 	p->dma_write(l, CLNK_CTRL, lch);
+	pm_runtime_put_autosuspend(dev);
 }
 
 static inline void disable_lnk(int lch)
 {
 	u32 l;
 
+	pm_runtime_get_sync(dev);
 	l = p->dma_read(CLNK_CTRL, lch);
 
 	/* Disable interrupts */
@@ -637,6 +678,7 @@  static inline void disable_lnk(int lch)
 
 	p->dma_write(l, CLNK_CTRL, lch);
 	dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
+	pm_runtime_put_autosuspend(dev);
 }
 
 static inline void omap2_enable_irq_lch(int lch)
@@ -647,11 +689,13 @@  static inline void omap2_enable_irq_lch(int lch)
 	if (!cpu_class_is_omap2())
 		return;
 
+	pm_runtime_get_sync(dev);
 	spin_lock_irqsave(&dma_chan_lock, flags);
 	val = p->dma_read(IRQENABLE_L0, lch);
 	val |= 1 << lch;
 	p->dma_write(val, IRQENABLE_L0, lch);
 	spin_unlock_irqrestore(&dma_chan_lock, flags);
+	pm_runtime_put_autosuspend(dev);
 }
 
 static inline void omap2_disable_irq_lch(int lch)
@@ -662,11 +706,13 @@  static inline void omap2_disable_irq_lch(int lch)
 	if (!cpu_class_is_omap2())
 		return;
 
+	pm_runtime_get_sync(dev);
 	spin_lock_irqsave(&dma_chan_lock, flags);
 	val = p->dma_read(IRQENABLE_L0, lch);
 	val &= ~(1 << lch);
 	p->dma_write(val, IRQENABLE_L0, lch);
 	spin_unlock_irqrestore(&dma_chan_lock, flags);
+	pm_runtime_put_autosuspend(dev);
 }
 
 int omap_request_dma(int dev_id, const char *dev_name,
@@ -677,6 +723,7 @@  int omap_request_dma(int dev_id, const char *dev_name,
 	unsigned long flags;
 	struct omap_dma_lch *chan;
 
+	pm_runtime_get_sync(dev);
 	spin_lock_irqsave(&dma_chan_lock, flags);
 	for (ch = 0; ch < dma_chan_count; ch++) {
 		if (free_ch == -1 && dma_chan[ch].dev_id == -1) {
@@ -687,6 +734,7 @@  int omap_request_dma(int dev_id, const char *dev_name,
 	}
 	if (free_ch == -1) {
 		spin_unlock_irqrestore(&dma_chan_lock, flags);
+		pm_runtime_put_autosuspend(dev);
 		return -EBUSY;
 	}
 	chan = dma_chan + free_ch;
@@ -744,6 +792,7 @@  int omap_request_dma(int dev_id, const char *dev_name,
 	}
 
 	*dma_ch_out = free_ch;
+	pm_runtime_put_autosuspend(dev);
 
 	return 0;
 }
@@ -758,7 +807,7 @@  void omap_free_dma(int lch)
 		       lch);
 		return;
 	}
-
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap1()) {
 		/* Disable all DMA interrupts for the channel. */
 		p->dma_write(0, CICR, lch);
@@ -780,7 +829,7 @@  void omap_free_dma(int lch)
 		p->dma_write(0, CCR, lch);
 		omap_clear_dma(lch);
 	}
-
+	pm_runtime_put_autosuspend(dev);
 	spin_lock_irqsave(&dma_chan_lock, flags);
 	dma_chan[lch].dev_id = -1;
 	dma_chan[lch].next_lch = -1;
@@ -818,7 +867,9 @@  omap_dma_set_global_params(int arb_rate, int max_fifo_depth, int tparams)
 	reg |= (0x3 & tparams) << 12;
 	reg |= (arb_rate & 0xff) << 16;
 
+	pm_runtime_get_sync(dev);
 	p->dma_write(reg, GCR, 0);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_dma_set_global_params);
 
@@ -841,6 +892,7 @@  omap_dma_set_prio_lch(int lch, unsigned char read_prio,
 		printk(KERN_ERR "Invalid channel id\n");
 		return -EINVAL;
 	}
+	pm_runtime_get_sync(dev);
 	l = p->dma_read(CCR, lch);
 	l &= ~((1 << 6) | (1 << 26));
 	if (cpu_is_omap2430() || cpu_is_omap34xx() ||  cpu_is_omap44xx())
@@ -849,6 +901,7 @@  omap_dma_set_prio_lch(int lch, unsigned char read_prio,
 		l |= ((read_prio & 0x1) << 6);
 
 	p->dma_write(l, CCR, lch);
+	pm_runtime_put_autosuspend(dev);
 
 	return 0;
 }
@@ -862,9 +915,11 @@  void omap_clear_dma(int lch)
 {
 	unsigned long flags;
 
+	pm_runtime_get_sync(dev);
 	local_irq_save(flags);
 	p->clear_dma(lch);
 	local_irq_restore(flags);
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_clear_dma);
 
@@ -872,6 +927,8 @@  void omap_start_dma(int lch)
 {
 	u32 l;
 
+	pm_runtime_get_sync(dev);
+
 	/*
 	 * The CPC/CDAC register needs to be initialized to zero
 	 * before starting dma transfer.
@@ -927,6 +984,7 @@  void omap_stop_dma(int lch)
 	u32 l;
 	unsigned long flags;
 
+	pm_runtime_get_sync(dev);
 	/* Disable all interrupts on the channel */
 	if (cpu_class_is_omap1())
 		p->dma_write(0, CICR, lch);
@@ -989,6 +1047,7 @@  void omap_stop_dma(int lch)
 	}
 
 	dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_stop_dma);
 
@@ -1031,6 +1090,7 @@  dma_addr_t omap_get_dma_src_pos(int lch)
 {
 	dma_addr_t offset = 0;
 
+	pm_runtime_get_sync(dev);
 	if (cpu_is_omap15xx())
 		offset = p->dma_read(CPC, lch);
 	else
@@ -1042,6 +1102,7 @@  dma_addr_t omap_get_dma_src_pos(int lch)
 	if (cpu_class_is_omap1())
 		offset |= (p->dma_read(CSSA, lch) & 0xFFFF0000);
 
+	pm_runtime_put_autosuspend(dev);
 	return offset;
 }
 EXPORT_SYMBOL(omap_get_dma_src_pos);
@@ -1058,6 +1119,7 @@  dma_addr_t omap_get_dma_dst_pos(int lch)
 {
 	dma_addr_t offset = 0;
 
+	pm_runtime_get_sync(dev);
 	if (cpu_is_omap15xx())
 		offset = p->dma_read(CPC, lch);
 	else
@@ -1073,13 +1135,20 @@  dma_addr_t omap_get_dma_dst_pos(int lch)
 	if (cpu_class_is_omap1())
 		offset |= (p->dma_read(CDSA, lch) & 0xFFFF0000);
 
+	pm_runtime_put_autosuspend(dev);
 	return offset;
 }
 EXPORT_SYMBOL(omap_get_dma_dst_pos);
 
 int omap_get_dma_active_status(int lch)
 {
-	return (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN) != 0;
+	u32 reg_data;
+
+	pm_runtime_get_sync(dev);
+	reg_data = p->dma_read(CCR, lch);
+	pm_runtime_put_autosuspend(dev);
+	reg_data &= reg_data & OMAP_DMA_CCR_EN;
+	return ((reg_data != 0) ? 1 : 0);
 }
 EXPORT_SYMBOL(omap_get_dma_active_status);
 
@@ -1087,14 +1156,20 @@  int omap_dma_running(void)
 {
 	int lch;
 
+	pm_runtime_get_sync(dev);
 	if (cpu_class_is_omap1())
-		if (omap_lcd_dma_running())
+		if (omap_lcd_dma_running()) {
+			pm_runtime_put_autosuspend(dev);
 			return 1;
+		}
 
 	for (lch = 0; lch < dma_chan_count; lch++)
-		if (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN)
+		if (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN) {
+			pm_runtime_put_autosuspend(dev);
 			return 1;
+		}
 
+	pm_runtime_put_autosuspend(dev);
 	return 0;
 }
 
@@ -1105,12 +1180,15 @@  int omap_dma_running(void)
  */
 void omap_dma_link_lch(int lch_head, int lch_queue)
 {
+	pm_runtime_get_sync(dev);
 	if (omap_dma_in_1510_mode()) {
 		if (lch_head == lch_queue) {
 			p->dma_write(p->dma_read(CCR, lch_head) | (3 << 8),
 								CCR, lch_head);
+			pm_runtime_put_autosuspend(dev);
 			return;
 		}
+		pm_runtime_put_autosuspend(dev);
 		printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
 		BUG();
 		return;
@@ -1124,6 +1202,7 @@  void omap_dma_link_lch(int lch_head, int lch_queue)
 	}
 
 	dma_chan[lch_head].next_lch = lch_queue;
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_dma_link_lch);
 
@@ -1132,12 +1211,15 @@  EXPORT_SYMBOL(omap_dma_link_lch);
  */
 void omap_dma_unlink_lch(int lch_head, int lch_queue)
 {
+	pm_runtime_get_sync(dev);
 	if (omap_dma_in_1510_mode()) {
 		if (lch_head == lch_queue) {
 			p->dma_write(p->dma_read(CCR, lch_head) & ~(3 << 8),
 								CCR, lch_head);
+			pm_runtime_put_autosuspend(dev);
 			return;
 		}
+		pm_runtime_put_autosuspend(dev);
 		printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
 		BUG();
 		return;
@@ -1158,6 +1240,7 @@  void omap_dma_unlink_lch(int lch_head, int lch_queue)
 	}
 
 	dma_chan[lch_head].next_lch = -1;
+	pm_runtime_put_autosuspend(dev);
 }
 EXPORT_SYMBOL(omap_dma_unlink_lch);
 
@@ -1167,6 +1250,7 @@  static void create_dma_lch_chain(int lch_head, int lch_queue)
 {
 	u32 l;
 
+	pm_runtime_get_sync(dev);
 	/* Check if this is the first link in chain */
 	if (dma_chan[lch_head].next_linked_ch == -1) {
 		dma_chan[lch_head].next_linked_ch = lch_queue;
@@ -1194,6 +1278,7 @@  static void create_dma_lch_chain(int lch_head, int lch_queue)
 	l &= ~(0x1f);
 	l |= (dma_chan[lch_queue].next_linked_ch);
 	p->dma_write(l, CLNK_CTRL, lch_queue);
+	pm_runtime_put_autosuspend(dev);
 }
 
 /**
@@ -1467,6 +1552,7 @@  int omap_dma_chain_a_transfer(int chain_id, int src_start, int dest_start,
 	/* Increment the q_tail */
 	OMAP_DMA_CHAIN_INCQTAIL(chain_id);
 
+	pm_runtime_get_sync(dev);
 	/* Set the params to the free channel */
 	if (src_start != 0)
 		p->dma_write(src_start, CSSA, lch);
@@ -1546,6 +1632,7 @@  int omap_dma_chain_a_transfer(int chain_id, int src_start, int dest_start,
 			dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
 		}
 	}
+	pm_runtime_put_autosuspend(dev);
 
 	return 0;
 }
@@ -1586,6 +1673,7 @@  int omap_start_dma_chain_transfers(int chain_id)
 		omap_enable_channel_irq(channels[0]);
 	}
 
+	pm_runtime_get_sync(dev);
 	l = p->dma_read(CCR, channels[0]);
 	l |= (1 << 7);
 	dma_linked_lch[chain_id].chain_state = DMA_CHAIN_STARTED;
@@ -1599,6 +1687,7 @@  int omap_start_dma_chain_transfers(int chain_id)
 
 	dma_chan[channels[0]].flags |= OMAP_DMA_ACTIVE;
 
+	pm_runtime_put_autosuspend(dev);
 	return 0;
 }
 EXPORT_SYMBOL(omap_start_dma_chain_transfers);
@@ -1630,6 +1719,7 @@  int omap_stop_dma_chain_transfers(int chain_id)
 	}
 	channels = dma_linked_lch[chain_id].linked_dmach_q;
 
+	pm_runtime_get_sync(dev);
 	if (IS_DMA_ERRATA(DMA_ERRATA_i88) && p->midlemode) {
 		spin_lock_irqsave(&dma_chan_lock, flags);
 		p->midlemode(true);
@@ -1658,6 +1748,7 @@  int omap_stop_dma_chain_transfers(int chain_id)
 		p->midlemode(false);
 		spin_unlock_irqrestore(&dma_chan_lock, flags);
 	}
+	pm_runtime_put_autosuspend(dev);
 
 	return 0;
 }
@@ -1691,16 +1782,19 @@  int omap_get_dma_chain_index(int chain_id, int *ei, int *fi)
 		printk(KERN_ERR "Chain doesn't exists\n");
 		return -EINVAL;
 	}
-	if ((!ei) || (!fi))
+	if ((!ei) || (!fi)) {
 		return -EINVAL;
+	}
 
 	channels = dma_linked_lch[chain_id].linked_dmach_q;
 
 	/* Get the current channel */
 	lch = channels[dma_linked_lch[chain_id].q_head];
 
+	pm_runtime_get_sync(dev);
 	*ei = p->dma_read(CCEN, lch);
 	*fi = p->dma_read(CCFN, lch);
+	pm_runtime_put_autosuspend(dev);
 
 	return 0;
 }
@@ -1719,6 +1813,7 @@  int omap_get_dma_chain_dst_pos(int chain_id)
 {
 	int lch;
 	int *channels;
+	int reg_data;
 
 	/* Check for input params */
 	if (unlikely((chain_id < 0 || chain_id >= dma_lch_count))) {
@@ -1737,7 +1832,10 @@  int omap_get_dma_chain_dst_pos(int chain_id)
 	/* Get the current channel */
 	lch = channels[dma_linked_lch[chain_id].q_head];
 
-	return p->dma_read(CDAC, lch);
+	pm_runtime_get_sync(dev);
+	reg_data = p->dma_read(CDAC, lch);
+	pm_runtime_put_autosuspend(dev);
+	return reg_data;
 }
 EXPORT_SYMBOL(omap_get_dma_chain_dst_pos);
 
@@ -1753,6 +1851,7 @@  int omap_get_dma_chain_src_pos(int chain_id)
 {
 	int lch;
 	int *channels;
+	int reg_data;
 
 	/* Check for input params */
 	if (unlikely((chain_id < 0 || chain_id >= dma_lch_count))) {
@@ -1771,7 +1870,10 @@  int omap_get_dma_chain_src_pos(int chain_id)
 	/* Get the current channel */
 	lch = channels[dma_linked_lch[chain_id].q_head];
 
-	return p->dma_read(CSAC, lch);
+	pm_runtime_get_sync(dev);
+	reg_data = p->dma_read(CSAC, lch);
+	pm_runtime_put_autosuspend(dev);
+	return reg_data;
 }
 EXPORT_SYMBOL(omap_get_dma_chain_src_pos);
 #endif	/* ifndef CONFIG_ARCH_OMAP1 */
@@ -1811,6 +1913,8 @@  static int omap1_dma_handle_ch(int ch)
 	if (likely(dma_chan[ch].callback != NULL))
 		dma_chan[ch].callback(ch, csr, dma_chan[ch].data);
 
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
 	return 1;
 }
 
@@ -1895,8 +1999,11 @@  static int omap2_dma_handle_ch(int ch)
 						OMAP_DMA_DYNAMIC_CHAIN)
 			disable_lnk(ch);
 
-		if (!OMAP_DMA_CHAIN_QEMPTY(chain_id))
+		if (!OMAP_DMA_CHAIN_QEMPTY(chain_id)) {
 			OMAP_DMA_CHAIN_INCQHEAD(chain_id);
+			pm_runtime_get_sync(dev);
+		}
+
 
 		status = p->dma_read(CSR, ch);
 		p->dma_write(status, CSR, ch);
@@ -1905,6 +2012,8 @@  static int omap2_dma_handle_ch(int ch)
 	if (likely(dma_chan[ch].callback != NULL))
 		dma_chan[ch].callback(ch, status, dma_chan[ch].data);
 
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
 	return 0;
 }
 
@@ -1945,17 +2054,20 @@  static struct irqaction omap24xx_dma_irq;
 
 void omap_dma_global_context_save(void)
 {
+	pm_runtime_get_sync(dev);
 	omap_dma_global_context.dma_irqenable_l0 =
 		p->dma_read(IRQENABLE_L0, 0);
 	omap_dma_global_context.dma_ocp_sysconfig =
 		p->dma_read(OCP_SYSCONFIG, 0);
 	omap_dma_global_context.dma_gcr = p->dma_read(GCR, 0);
+	pm_runtime_put_autosuspend(dev);
 }
 
 void omap_dma_global_context_restore(void)
 {
 	int ch;
 
+	pm_runtime_get_sync(dev);
 	p->dma_write(omap_dma_global_context.dma_gcr, GCR, 0);
 	p->dma_write(omap_dma_global_context.dma_ocp_sysconfig,
 		OCP_SYSCONFIG, 0);
@@ -1968,6 +2080,7 @@  void omap_dma_global_context_restore(void)
 	for (ch = 0; ch < dma_chan_count; ch++)
 		if (dma_chan[ch].dev_id != -1)
 			omap_clear_dma(ch);
+	pm_runtime_put_autosuspend(dev);
 }
 
 static int __devinit omap_system_dma_probe(struct platform_device *pdev)
@@ -1984,6 +2097,7 @@  static int __devinit omap_system_dma_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
+	dev			= &pdev->dev;
 	d			= p->dma_attr;
 	errata			= p->errata;
 
@@ -2005,6 +2119,11 @@  static int __devinit omap_system_dma_probe(struct platform_device *pdev)
 		}
 	}
 
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_set_autosuspend_delay(dev, 1000);
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+
 	spin_lock_init(&dma_chan_lock);
 	for (ch = 0; ch < dma_chan_count; ch++) {
 		omap_clear_dma(ch);
@@ -2070,6 +2189,16 @@  static int __devinit omap_system_dma_probe(struct platform_device *pdev)
 		dma_chan[1].dev_id = 1;
 	}
 	p->show_dma_caps();
+
+	/*
+	 * Note: If dma channels are reserved through boot paramters,
+	 * then dma device is always enabled.
+	 */
+	if (omap_dma_reserve_channels)
+		pm_runtime_get(dev);
+
+	pm_runtime_put_autosuspend(dev);
+
 	return 0;
 
 exit_dma_irq_fail:
@@ -2091,6 +2220,9 @@  static int __devexit omap_system_dma_remove(struct platform_device *pdev)
 {
 	int dma_irq;
 
+	if (omap_dma_reserve_channels)
+		pm_runtime_put_autosuspend(dev);
+
 	if (cpu_class_is_omap2()) {
 		char irq_name[4];
 		strcpy(irq_name, "0");