ARM: OMAP2xxx: PM: clean up some crufty powerstate programming code

Don't attempt to put clockdomains to sleep; this should be handled by the
clock framework.  It should be enough to program the next-power-state,
and then let the code in omap_pm_clkdms_setup() deal with the rest.

Start out by programming the MPU and CORE powerdomains to stay ON.
Then control the MPU and CORE powerdomain states directly in
omap2_enter_full_retention() and omap2_enter_mpu_retention().  Not the
most optimal way to do it, but certainly is the most conservative until
OMAP2xxx PM is working again.

Get rid of the open-coded PM_PWSTCTRL_MPU writes in
omap2_enter_mpu_retention(); use the powerdomain code instead.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-omap2/pm24xx.c

@@ -90,11 +90,7 @@ static int omap2_enter_full_retention(void)
 	omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 	omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 
-	/*
-	 * Set MPU powerdomain's next power state to RETENTION;
-	 * preserve logic state during retention
-	 */
-	pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
+	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
 	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 
 	/* Workaround to kill USB */
@@ -137,6 +133,9 @@ static int omap2_enter_full_retention(void)
 	/* Mask future PRCM-to-MPU interrupts */
 	omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 
+	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
+	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
+
 	return 0;
 }
 
@@ -186,17 +185,16 @@ static void omap2_enter_mpu_retention(void)
 		omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 
 		/* Try to enter MPU retention */
-		omap2_prm_write_mod_reg((0x01 << OMAP_POWERSTATE_SHIFT) |
-				  OMAP_LOGICRETSTATE_MASK,
-				  MPU_MOD, OMAP2_PM_PWSTCTRL);
+		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
+
 	} else {
 		/* Block MPU retention */
-
-		omap2_prm_write_mod_reg(OMAP_LOGICRETSTATE_MASK, MPU_MOD,
-						 OMAP2_PM_PWSTCTRL);
+		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 	}
 
 	omap2_sram_idle();
+
+	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 }
 
 static int omap2_can_sleep(void)
@@ -251,25 +249,17 @@ static void __init prcm_setup_regs(void)
 	for (i = 0; i < num_mem_banks; i++)
 		pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 
-	/* Set CORE powerdomain's next power state to RETENTION */
-	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
+	pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
 
-	/*
-	 * Set MPU powerdomain's next power state to RETENTION;
-	 * preserve logic state during retention
-	 */
 	pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
-	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 
 	/* Force-power down DSP, GFX powerdomains */
 
 	pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
-	clkdm_sleep(dsp_clkdm);
 
 	pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
-	clkdm_sleep(gfx_clkdm);
 
 	/* Enable hardware-supervised idle for all clkdms */
 	clkdm_for_each(omap_pm_clkdms_setup, NULL);