servo_v4: Support to enable Type C DTS mode

- Defined the config option CONFIG_USB_PD_DTS to board.h.
- Added ccd_set_mode function in board.c
- Removed ccd attach/detach functions from board.c as that function is
- now integrated in the the usb_pd state machine.
- Removed the fixed polarity that was being used in usb_pd_config.h so
  that the DUT port could connect as a SNK device.
- Defined PD_ROLE_DEFAULT to override the value in usb_Pd.h so that
  CHG is SNK and DUT is SRC

This set of changes allows servo_v4 to act like a suzyq. Hoever, PD
messaging is still not supported. The CHG port can still connect as a
SNK device, but VBUS on the DUT is only being provided by the host and
not the CHG port.

BUG=chrome-os-partner:61878
BRANCH=None
TEST=Manual Connected zinger to CHG port and verifed via servo_v4
console that it reached SNK_READY. Connected DUT port to Reef and
verified that it reached SRC_ACCESSORY state and that the correct SBU
polarity was selected and that lsusb shows H1 as a USB device.
Bus 003 Device 042: ID 18d1:5014 Google Inc.

Change-Id: I4a0ab2468f383a3ba4db3a3236bb18df6a2c405a
Signed-off-by: Scott <scollyer@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/428309
Commit-Ready: Scott Collyer <scollyer@chromium.org>
Tested-by: Scott Collyer <scollyer@chromium.org>
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

1 files changed, 19 insertions, 8 deletions

diff --git a/board/servo_v4/usb_pd_policy.c b/board/servo_v4/usb_pd_policy.c
index e26562794b..48cce3519b 100644
--- a/board/servo_v4/usb_pd_policy.c
+++ b/board/servo_v4/usb_pd_policy.c
@@ -59,21 +59,32 @@ void pd_transition_voltage(int idx)
 
 int pd_set_power_supply_ready(int port)
 {
+	/* Port 0 can never provide vbus. */
+	if (!port)
+		return EC_ERROR_INVAL;
+
+	/*
+	 * TODO(crosbug.com/p/60794): For now always assume VBUS is supplied by
+	 * host. No support yet for using CHG VBUS passthru mode.
+	 */
+
 	/*
-	 * TODO(crosbug.com/p/60794): Will likely need to set the GPIOs
-	 * DUT_CHG_EN and HOST_OR_CHG_CTL which control whether DUT port
-	 * provides VBUS from Host or CHG port.
+	 * Select Host as source for VBUS.
+	 * To select host, set GPIO_HOST_OR_CHG_CTL low. To select CHG as VBUS
+	 * source, then set GPIO_HOST_OR_CHG_CTL high.
 	 */
+	gpio_set_level(GPIO_HOST_OR_CHG_CTL, 0);
+
+	/* Enable VBUS from the source selected above. */
+	gpio_set_level(GPIO_DUT_CHG_EN, 1);
+
 	return EC_SUCCESS; /* we are ready */
 }
 
 void pd_power_supply_reset(int port)
 {
-	/*
-	 * TODO(crosbug.com/p/60794): Will need to set the GPIOs
-	 * DUT_CHG_EN and HOST_OR_CHG_CTL which control whether DUT port
-	 * provides VBUS from Host or CHG port.
-	 */
+	/* Disable VBUS */
+	gpio_set_level(GPIO_DUT_CHG_EN, 0);
 }
 
 void pd_set_input_current_limit(int port, uint32_t max_ma,