cr50: Merge CCD device handling to rdd.c

The device_state module is used for debouncing GPIO inputs to
determine device sstate.  It was overkill for managing the CCD cable
(RDD) attach/detach state, and split that handling between 3 files
(board.c, rdd.c, device_state.c).  Move all of that logic into rdd.c
so it's easier to maintain.

BUG=none
BRANCH=cr50
TEST=manual
     plug in CCD cable (or ground DIOM1)
     ccd command reports cable connected and AP UART TX+RX
     unplug CCD cable (or un-ground DIOM1)
     ccd command reports cable disconnected and AP UART disabled

Change-Id: Id8fcd3a51605ae7a4843668ea18dd0ef84aceb2c
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/604499
Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>

3 files changed, 8 insertions, 38 deletions

diff --git a/board/cr50/board.c b/board/cr50/board.c
index eb78139438..00e612c16a 100644
--- a/board/cr50/board.c
+++ b/board/cr50/board.c
@@ -1086,11 +1086,6 @@ struct device_config device_states[] = {
 		.detect = GPIO_BATT_PRES_L,
 		.name = "BattPrsnt"
 	},
-	[DEVICE_CCD_MODE] = {
-		.deferred = NULL,
-		.detect = GPIO_CCD_MODE_L,
-		.name = "CCD Mode"
-	},
 };
 BUILD_ASSERT(ARRAY_SIZE(device_states) == DEVICE_COUNT);
 
@@ -1220,30 +1215,6 @@ void board_update_device_state(enum device_type device)
 		return;
 	}
 
-	if (device == DEVICE_CCD_MODE) {
-		/*
-		 * CCD mode pin does not have an interrupt handler, so this is
-		 * the only way the CCD MODE device state changes.
-		 *
-		 * This could potentially be moved to a HOOK_SECOND handler
-		 * in rdd.c, since nothing else cares.
-		 */
-
-		int pin_level = gpio_get_level(device_states[device].detect);
-		/* The CCD mode pin is active low. */
-		int changed = device_set_state(device,
-					       pin_level ?
-					       DEVICE_STATE_OFF :
-					       DEVICE_STATE_ON);
-
-		if (changed) {
-			CPRINTS("CCD MODE changed: %d", pin_level);
-			ccd_mode_pin_changed(pin_level);
-		}
-
-		return;
-	}
-
 	if (device == DEVICE_SERVO) {
 		/*
 		 * If we're driving the transmit line to the EC UART, then we
diff --git a/board/cr50/board.h b/board/cr50/board.h
index 665361b125..6909180e3d 100644
--- a/board/cr50/board.h
+++ b/board/cr50/board.h
@@ -175,7 +175,6 @@ enum device_type {
 	DEVICE_EC,
 	DEVICE_SERVO,
 	DEVICE_BATTERY_PRESENT,
-	DEVICE_CCD_MODE,
 
 	DEVICE_COUNT
 };
diff --git a/board/cr50/rdd.c b/board/cr50/rdd.c
index 74ea87eff0..be5bf3417d 100644
--- a/board/cr50/rdd.c
+++ b/board/cr50/rdd.c
@@ -144,8 +144,6 @@ void rdd_attached(void)
 	GWRITE(PINMUX, DIOM1_SEL, GC_PINMUX_GPIO0_GPIO5_SEL);
 	/* Indicate case-closed debug mode (active low) */
 	gpio_set_flags(GPIO_CCD_MODE_L, GPIO_OUT_LOW);
-
-	/* The device state module will handle the actual enabling of CCD. */
 }
 
 void rdd_detached(void)
@@ -161,21 +159,23 @@ void rdd_detached(void)
 	 */
 	if (!keep_ccd_enabled)
 		gpio_set_flags(GPIO_CCD_MODE_L, GPIO_INPUT);
-
-	/* The device state module will handle the disabling of CCD. */
 }
 
-void ccd_mode_pin_changed(int pin_level)
+static void rdd_check_pin(void)
 {
-	/* Inverted because active low. */
-	int enable = pin_level ? 0 : 1;
+	/* The CCD mode pin is active low. */
+	int enable = !gpio_get_level(GPIO_CCD_MODE_L);
 
 	/* Keep CCD enabled if it's being forced enabled. */
-	if (!enable && keep_ccd_enabled)
+	if (keep_ccd_enabled)
+		enable = 1;
+
+	if (enable == ccd_is_enabled())
 		return;
 
 	configure_ccd(enable);
 }
+DECLARE_HOOK(HOOK_SECOND, rdd_check_pin, HOOK_PRIO_DEFAULT);
 
 static void rdd_ccd_change_hook(void)
 {