Add support for calling deferred functions

This is a cleaner way of deferring work from interrupt-time to
task-time without requiring a task for each module which needs this.

Replaces/supersedes delayed hook notification, which didn't scale well
(since every function would have needed to be its own hook type).

BUG=chrome-os-partner:18473
BRANCH=none
TEST=boot system.  plug/unplug AC power; notifies the host properly

Change-Id: I50263fe1ce37e74c1ef8db3671379098997102ed
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/46953
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

1 files changed, 7 insertions, 4 deletions

diff --git a/common/extpower_gpio.c b/common/extpower_gpio.c
index 218905f91d..4643b245de 100644
--- a/common/extpower_gpio.c
+++ b/common/extpower_gpio.c
@@ -17,19 +17,22 @@ int extpower_is_present(void)
 }
 
 /**
- * Handle notification of external power change; forward it to host.
+ * Deferred function to handle external power change
  */
-static void extpower_changed(void)
+static void extpower_deferred(void)
 {
+	hook_notify(HOOK_AC_CHANGE);
+
+	/* Forward notification to host */
 	if (extpower_is_present())
 		host_set_single_event(EC_HOST_EVENT_AC_CONNECTED);
 	else
 		host_set_single_event(EC_HOST_EVENT_AC_DISCONNECTED);
 }
-DECLARE_HOOK(HOOK_AC_CHANGE, extpower_changed, HOOK_PRIO_DEFAULT);
+DECLARE_DEFERRED(extpower_deferred);
 
 void extpower_interrupt(enum gpio_signal signal)
 {
 	/* Trigger deferred notification of external power change */
-	hook_notify(HOOK_AC_CHANGE);
+	hook_call_deferred(extpower_deferred, 0);
 }