3 files changed, 18 insertions, 5 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index c2c798c08c2b..a202a4785104 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -1368,7 +1368,9 @@ static void _enable_sysc(struct omap_hwmod *oh)
         }
 
         if (sf & SYSC_HAS_MIDLEMODE) {
-                if (oh->flags & HWMOD_SWSUP_MSTANDBY) {
+                if (oh->flags & HWMOD_FORCE_MSTANDBY) {
+                        idlemode = HWMOD_IDLEMODE_FORCE;
+                } else if (oh->flags & HWMOD_SWSUP_MSTANDBY) {
                         idlemode = HWMOD_IDLEMODE_NO;
                 } else {
                         if (sf & SYSC_HAS_ENAWAKEUP)
@@ -1440,7 +1442,8 @@ static void _idle_sysc(struct omap_hwmod *oh)
         }
 
         if (sf & SYSC_HAS_MIDLEMODE) {
-                if (oh->flags & HWMOD_SWSUP_MSTANDBY) {
+                if ((oh->flags & HWMOD_SWSUP_MSTANDBY) ||
+                    (oh->flags & HWMOD_FORCE_MSTANDBY)) {
                         idlemode = HWMOD_IDLEMODE_FORCE;
                 } else {
                         if (sf & SYSC_HAS_ENAWAKEUP)
diff --git a/arch/arm/mach-omap2/omap_hwmod.h b/arch/arm/mach-omap2/omap_hwmod.h
index d43d9b608eda..d5dc935f6060 100644
--- a/arch/arm/mach-omap2/omap_hwmod.h
+++ b/arch/arm/mach-omap2/omap_hwmod.h
@@ -427,8 +427,8 @@ struct omap_hwmod_omap4_prcm {
  *
  * HWMOD_SWSUP_SIDLE: omap_hwmod code should manually bring module in and out
  *     of idle, rather than relying on module smart-idle
- * HWMOD_SWSUP_MSTDBY: omap_hwmod code should manually bring module in and out
- *     of standby, rather than relying on module smart-standby
+ * HWMOD_SWSUP_MSTANDBY: omap_hwmod code should manually bring module in and
+ *     out of standby, rather than relying on module smart-standby
  * HWMOD_INIT_NO_RESET: don't reset this module at boot - important for
  *     SDRAM controller, etc. XXX probably belongs outside the main hwmod file
  *     XXX Should be HWMOD_SETUP_NO_RESET
@@ -459,6 +459,10 @@ struct omap_hwmod_omap4_prcm {
  *     correctly, or this is being abused to deal with some PM latency
  *     issues -- but we're currently suffering from a shortage of
  *     folks who are able to track these issues down properly.
+ * HWMOD_FORCE_MSTANDBY: Always keep MIDLEMODE bits cleared so that device
+ *     is kept in force-standby mode. Failing to do so causes PM problems
+ *     with musb on OMAP3630 at least. Note that musb has a dedicated register
+ *     to control MSTANDBY signal when MIDLEMODE is set to force-standby.
  */
 #define HWMOD_SWSUP_SIDLE                       (1 << 0)
 #define HWMOD_SWSUP_MSTANDBY                    (1 << 1)
@@ -471,6 +475,7 @@ struct omap_hwmod_omap4_prcm {
 #define HWMOD_16BIT_REG                         (1 << 8)
 #define HWMOD_EXT_OPT_MAIN_CLK                  (1 << 9)
 #define HWMOD_BLOCK_WFI                         (1 << 10)
+#define HWMOD_FORCE_MSTANDBY                    (1 << 11)
 
 /*
  * omap_hwmod._int_flags definitions
diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index ac7e03ec952f..5112d04e7b79 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -1707,9 +1707,14 @@ static struct omap_hwmod omap3xxx_usbhsotg_hwmod = {
          * Erratum ID: i479  idle_req / idle_ack mechanism potentially
          * broken when autoidle is enabled
          * workaround is to disable the autoidle bit at module level.
+         *
+         * Enabling the device in any other MIDLEMODE setting but force-idle
+         * causes core_pwrdm not enter idle states at least on OMAP3630.
+         * Note that musb has OTG_FORCESTDBY register that controls MSTANDBY
+         * signal when MIDLEMODE is set to force-idle.
          */
         .flags          = HWMOD_NO_OCP_AUTOIDLE | HWMOD_SWSUP_SIDLE
-                                | HWMOD_SWSUP_MSTANDBY,
+                                | HWMOD_FORCE_MSTANDBY,
 };
 
 /* usb_otg_hs */