ARM: OMAP3: PM: call pre/post transition per powerdomain

We only need to call the pre/post transtion methods when we know the
power state is changing.  First, split up the pre/post transition
calls to be per-powerdomain, and then make them conditional on whether
the power domain is actually changing states.
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NGrazvydas Ignotas <notasas@gmail.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

arch/arm/mach-omap2/pm34xx.c

@@ -273,16 +273,21 @@ void omap_sram_idle(void)
 	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
 	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
 
-	pwrdm_pre_transition(NULL);
+	if (mpu_next_state < PWRDM_POWER_ON) {
+		pwrdm_pre_transition(mpu_pwrdm);
+		pwrdm_pre_transition(neon_pwrdm);
+	}
 
 	/* PER */
 	if (per_next_state < PWRDM_POWER_ON) {
+		pwrdm_pre_transition(per_pwrdm);
 		per_going_off = (per_next_state == PWRDM_POWER_OFF) ? 1 : 0;
 		omap2_gpio_prepare_for_idle(per_going_off);
 	}
 
 	/* CORE */
 	if (core_next_state < PWRDM_POWER_ON) {
+		pwrdm_pre_transition(core_pwrdm);
 		if (core_next_state == PWRDM_POWER_OFF) {
 			omap3_core_save_context();
 			omap3_cm_save_context();
@@ -335,14 +340,20 @@ void omap_sram_idle(void)
 			omap2_prm_clear_mod_reg_bits(OMAP3430_AUTO_OFF_MASK,
 					       OMAP3430_GR_MOD,
 					       OMAP3_PRM_VOLTCTRL_OFFSET);
+		pwrdm_post_transition(core_pwrdm);
 	}
 	omap3_intc_resume_idle();
 
-	pwrdm_post_transition(NULL);
-
 	/* PER */
-	if (per_next_state < PWRDM_POWER_ON)
+	if (per_next_state < PWRDM_POWER_ON) {
 		omap2_gpio_resume_after_idle();
+		pwrdm_post_transition(per_pwrdm);
+	}
+
+	if (mpu_next_state < PWRDM_POWER_ON) {
+		pwrdm_post_transition(mpu_pwrdm);
+		pwrdm_post_transition(neon_pwrdm);
+	}
 
 	clkdm_allow_idle(mpu_pwrdm->pwrdm_clkdms[0]);
 }