OMAP2+: hwmod: allow custom pre-shutdown functions

Some OMAP IP blocks, such as the watchdog timers, cannot be completely
shut down via the standard hwmod shutdown mechanism.  This patch
enables the hwmod data files to supply a pointer to a custom
pre-shutdown function via the struct omap_hwmod_class.pre_shutdown
function pointer.  If the struct omap_hwmod_class.pre_shutdown
function pointer is non-null, the function will be executed before the
existing hwmod shutdown code runs.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Benoît Cousson <b-cousson@ti.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 5a30658444d0..c051fa493594 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -1261,6 +1261,9 @@ int _omap_hwmod_idle(struct omap_hwmod *oh)
  */
 static int _shutdown(struct omap_hwmod *oh)
 {
+        int ret;
+        u8 prev_state;
+
         if (oh->_state != _HWMOD_STATE_IDLE &&
             oh->_state != _HWMOD_STATE_ENABLED) {
                 WARN(1, "omap_hwmod: %s: disabled state can only be entered "
@@ -1270,6 +1273,18 @@ static int _shutdown(struct omap_hwmod *oh)
 
         pr_debug("omap_hwmod: %s: disabling\n", oh->name);
 
+        if (oh->class->pre_shutdown) {
+                prev_state = oh->_state;
+                if (oh->_state == _HWMOD_STATE_IDLE)
+                        _omap_hwmod_enable(oh);
+                ret = oh->class->pre_shutdown(oh);
+                if (ret) {
+                        if (prev_state == _HWMOD_STATE_IDLE)
+                                _omap_hwmod_idle(oh);
+                        return ret;
+                }
+        }
+
         if (oh->class->sysc)
                 _shutdown_sysc(oh);