3 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c
index 4a91d38d7b1a..f9f0bca1926a 100644
--- a/arch/arm/mach-omap2/powerdomain.c
+++ b/arch/arm/mach-omap2/powerdomain.c
@@ -980,6 +980,34 @@ bool pwrdm_has_hdwr_sar(struct powerdomain *pwrdm)
 }
 
 /**
+ * pwrdm_set_lowpwrstchange - Request a low power state change
+ * @pwrdm: struct powerdomain *
+ *
+ * Allows a powerdomain to transtion to a lower power sleep state
+ * from an existing sleep state without waking up the powerdomain.
+ * Returns -EINVAL if the powerdomain pointer is null or if the
+ * powerdomain does not support LOWPOWERSTATECHANGE, or returns 0
+ * upon success.
+ */
+int pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
+{
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (!(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE))
+		return -EINVAL;
+
+	pr_debug("powerdomain: %s: setting LOWPOWERSTATECHANGE bit\n",
+		 pwrdm->name);
+
+	prm_rmw_mod_reg_bits(OMAP4430_LOWPOWERSTATECHANGE_MASK,
+			     (1 << OMAP4430_LOWPOWERSTATECHANGE_SHIFT),
+			     pwrdm->prcm_offs, pwrstctrl_reg_offs);
+
+	return 0;
+}
+
+/**
  * pwrdm_wait_transition - wait for powerdomain power transition to finish
  * @pwrdm: struct powerdomain * to wait for
  *
diff --git a/arch/arm/mach-omap2/powerdomains44xx.h b/arch/arm/mach-omap2/powerdomains44xx.h
index ad5a2655ad44..c7219513472a 100644
--- a/arch/arm/mach-omap2/powerdomains44xx.h
+++ b/arch/arm/mach-omap2/powerdomains44xx.h
@@ -54,6 +54,7 @@ static struct powerdomain core_44xx_pwrdm = {
 		[3] = PWRDM_POWER_ON,	/* ducati_l2ram */
 		[4] = PWRDM_POWER_ON,	/* ducati_unicache */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* gfx_44xx_pwrdm: 3D accelerator power domain */
@@ -69,6 +70,7 @@ static struct powerdomain gfx_44xx_pwrdm = {
 	.pwrsts_mem_on	= {
 		[0] = PWRDM_POWER_ON,	/* gfx_mem */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* abe_44xx_pwrdm: Audio back end power domain */
@@ -87,6 +89,7 @@ static struct powerdomain abe_44xx_pwrdm = {
 		[0] = PWRDM_POWER_ON,	/* aessmem */
 		[1] = PWRDM_POWER_ON,	/* periphmem */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* dss_44xx_pwrdm: Display subsystem power domain */
@@ -103,6 +106,7 @@ static struct powerdomain dss_44xx_pwrdm = {
 	.pwrsts_mem_on	= {
 		[0] = PWRDM_POWER_ON,	/* dss_mem */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* tesla_44xx_pwrdm: Tesla processor power domain */
@@ -123,6 +127,7 @@ static struct powerdomain tesla_44xx_pwrdm = {
 		[1] = PWRDM_POWER_ON,	/* tesla_l1 */
 		[2] = PWRDM_POWER_ON,	/* tesla_l2 */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* wkup_44xx_pwrdm: Wake-up power domain */
@@ -227,6 +232,7 @@ static struct powerdomain ivahd_44xx_pwrdm = {
 		[2] = PWRDM_POWER_ON,	/* tcm1_mem */
 		[3] = PWRDM_POWER_ON,	/* tcm2_mem */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* cam_44xx_pwrdm: Camera subsystem power domain */
@@ -242,6 +248,7 @@ static struct powerdomain cam_44xx_pwrdm = {
 	.pwrsts_mem_on	= {
 		[0] = PWRDM_POWER_ON,	/* cam_mem */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* l3init_44xx_pwrdm: L3 initators pheripherals power domain  */
@@ -258,6 +265,7 @@ static struct powerdomain l3init_44xx_pwrdm = {
 	.pwrsts_mem_on	= {
 		[0] = PWRDM_POWER_ON,	/* l3init_bank1 */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /* l4per_44xx_pwrdm: Target peripherals power domain */
@@ -276,6 +284,7 @@ static struct powerdomain l4per_44xx_pwrdm = {
 		[0] = PWRDM_POWER_ON,	/* nonretained_bank */
 		[1] = PWRDM_POWER_ON,	/* retained_bank */
 	},
+	.flags		= PWRDM_HAS_LOWPOWERSTATECHANGE,
 };
 
 /*
diff --git a/arch/arm/plat-omap/include/plat/powerdomain.h b/arch/arm/plat-omap/include/plat/powerdomain.h
index e7cc7e66e977..fb6ec74fe39e 100644
--- a/arch/arm/plat-omap/include/plat/powerdomain.h
+++ b/arch/arm/plat-omap/include/plat/powerdomain.h
@@ -50,6 +50,12 @@
 					  * in MEM bank 1 position. This is
 					  * true for OMAP3430
 					  */
+#define PWRDM_HAS_LOWPOWERSTATECHANGE	(1 << 2) /*
+						  * support to transition from a
+						  * sleep state to a lower sleep
+						  * state without waking up the
+						  * powerdomain
+						  */
 
 /*
  * Number of memory banks that are power-controllable.	On OMAP4430, the