mkbp_event,include/config.h: Clarify MKBP delivery method.

Now we have two MKBP delivery methods:
1. define CONFIG_MKBP_USE_HOST_EVENT to notify via host event
2. undef CONFIG_MKBP_USE_HOST_EVENT to notify via GPIO interrupt

It may become more complicated if new notification methods introduced.
e.g.: mt_scp uses IPI, rather than host event and GPIO interrupt.
This CL does:
1. add CONFIG_MKBP_USE_GPIO to explicilty declare that MKBP event are
   sent via GPIO interrupt.
2. CONFIG_MKBP_USE_CUSTOM for boards which have custmized methods.
3. Remove weak attribute in mkbp_set_host_active (which can be done
   with CONFIG_MKBP_USE_CUSTOM now.
4. Removes mkbp_set_host_active function in board Nocturne.  It only
   deliver MKBP events through GPIO interrupt now.

BRANCH=None
BUG=b:120808999
TEST=grep -rn "CONFIG_MKBP_USE_GPIO\|EC_INT_L" board/ baseboard/ and
     see the result is reasonable:
     1. EC_INT_L must be 1-to-1 mapped to define CONFIG_MKBP_USE_GPIO in
        every board, except that meep, yorp, ampton which are defined in
        baseboard octopus.
     2. undef CONFIG_MKBP_USE_GPIO in bip and casta, which use host
        event, but also have baseboard octopus.

Change-Id: I4af6110e4fd3c009968075c3623ef2d91cbd770b
Signed-off-by: Yilun Lin <yllin@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1490794
Commit-Ready: Jett Rink <jettrink@chromium.org>
Tested-by: Yilun Lin <yllin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-by: Jett Rink <jettrink@chromium.org>

1 files changed, 8 insertions, 4 deletions

diff --git a/common/mkbp_event.c b/common/mkbp_event.c
index 9dddcab519..b4b163121d 100644
--- a/common/mkbp_event.c
+++ b/common/mkbp_event.c
@@ -33,24 +33,28 @@ static int event_is_set(uint8_t event_type)
 	return events & (1 << event_type);
 }
 
-#ifndef CONFIG_MKBP_USE_HOST_EVENT
+#ifdef CONFIG_MKBP_USE_GPIO
 void mkbp_set_host_active_via_gpio(int active)
 {
 	gpio_set_level(GPIO_EC_INT_L, !active);
 }
 #endif
 
+#ifdef CONFIG_MKBP_USE_HOST_EVENT
 void mkbp_set_host_active_via_event(int active)
 {
 	if (active)
 		host_set_single_event(EC_HOST_EVENT_MKBP);
 }
+#endif
 
-__attribute__((weak)) void mkbp_set_host_active(int active)
+void mkbp_set_host_active(int active)
 {
-#ifdef CONFIG_MKBP_USE_HOST_EVENT
+#if defined(CONFIG_MKBP_USE_CUSTOM)
+	mkbp_set_host_active_via_custom(active);
+#elif defined(CONFIG_MKBP_USE_HOST_EVENT)
 	mkbp_set_host_active_via_event(active);
-#else
+#elif defined(CONFIG_MKBP_USE_GPIO)
 	mkbp_set_host_active_via_gpio(active);
 #endif
 }