From: Tero Kristo <tero.kri...@nokia.com>

Smartreflex for the corresponding powerdomain (MPU/CORE) must be disabled
before the domain enters retention, otherwise the device may hang. This is
caused by overlapping smartreflex / auto retention command on the voltage
channel resulting in incorrect voltage.

This fix has been confirmed from TI.

Signed-off-by: Tero Kristo <tero.kri...@nokia.com>
---
 arch/arm/mach-omap2/pm34xx.c |   23 ++++++++++++++++++-----
 1 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 3e5ae14..5854fa7 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -531,11 +531,17 @@ void omap_sram_idle(void)
        if (pwrdm_read_pwrst(cam_pwrdm) == PWRDM_POWER_ON)
                omap2_clkdm_deny_idle(mpu_pwrdm->pwrdm_clkdms[0]);
 
-       /* CORE */
-       if (core_next_state < PWRDM_POWER_ON) {
-               /* Disable smartreflex before entering WFI */
+       /*
+        * Disable smartreflex before entering WFI.
+        * Only needed if we are going to enter retention or off.
+        */
+       if (mpu_next_state <= PWRDM_POWER_RET)
                disable_smartreflex(SR1);
+       if (core_next_state <= PWRDM_POWER_RET)
                disable_smartreflex(SR2);
+
+       /* CORE */
+       if (core_next_state < PWRDM_POWER_ON) {
                omap_uart_prepare_idle(0);
                omap_uart_prepare_idle(1);
                if (core_next_state == PWRDM_POWER_OFF) {
@@ -608,10 +614,17 @@ void omap_sram_idle(void)
                        prm_clear_mod_reg_bits(OMAP3430_AUTO_RET,
                                                OMAP3430_GR_MOD,
                                                OMAP3_PRM_VOLTCTRL_OFFSET);
-               /* Enable smartreflex after WFI */
+       }
+
+       /*
+        * Enable smartreflex after WFI. Only needed if we
+        * entered retention or off.
+        */
+       if (mpu_next_state <= PWRDM_POWER_RET)
                enable_smartreflex(SR1);
+       if (core_next_state <= PWRDM_POWER_RET)
                enable_smartreflex(SR2);
-       }
+
        if (core_saved_state != core_next_state)
                pwrdm_set_next_pwrst(core_pwrdm, core_saved_state);
 
-- 
1.5.4.3

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