pd: Enable alternate mode support for DP.

Change effects:
1. samus_pd: Acts as initiator of SVDM discovery once its reaches source
             ready and upon identifying UFP with display port
	     alternate mode enters that mode.
2. hoho: Acts as responder for SVDM discovery providing its identity,
         svids and svid capabilities which are display port only.  If
	 asked to enter display port alternate mode it does.
3. fruitpie: Acts a initiator with mock display port mode.

BRANCH=none
BUG=chrome-os-partner:30645
TEST=manual,
Plug hoho into samus_pd
- see dpout
- from console
  > typec 0
  Port C0: CC1 451 mV  CC2 111 mV (polarity:CC1)
  Superspeed DP1

Change-Id: I1a76767353a69baeceffa3e79c37dcea77b8337d
Signed-off-by: Todd Broch <tbroch@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/221354
Reviewed-by: Alec Berg <alecaberg@chromium.org>
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/board/samus_pd/usb_pd_policy.c b/board/samus_pd/usb_pd_policy.c
index 7b7237059b..dce1407ec3 100644
--- a/board/samus_pd/usb_pd_policy.c
+++ b/board/samus_pd/usb_pd_policy.c
@@ -158,6 +158,12 @@ static void pd_send_host_event(void)
 }
 
 /* ----------------- Vendor Defined Messages ------------------ */
+const struct svdm_response svdm_rsp = {
+	.identity = NULL,
+	.svids = NULL,
+	.modes = NULL,
+};
+
 static int pd_custom_vdm(int port, int cnt, uint32_t *payload,
 			 uint32_t **rpayload)
 {
@@ -208,6 +214,41 @@ int pd_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
 		return pd_custom_vdm(port, cnt, payload, rpayload);
 }
 
+static void svdm_enter_dp_mode(int port, uint32_t mode_caps)
+{
+	board_set_usb_mux(port, TYPEC_MUX_DP, pd_get_polarity(port));
+}
+
+static void svdm_exit_dp_mode(int port)
+{
+	board_set_usb_mux(port, TYPEC_MUX_NONE, pd_get_polarity(port));
+}
+
+const struct svdm_amode_fx supported_modes[] = {
+	{
+		.svid = USB_SID_DISPLAYPORT,
+		.enter = &svdm_enter_dp_mode,
+		.exit = &svdm_exit_dp_mode,
+	},
+};
+
+void pd_dfp_choose_modes(struct pd_policy *pe)
+{
+	int i, j;
+	pe->amode_cnt = ARRAY_SIZE(supported_modes);
+	pe->amodes->fx = supported_modes;
+	for (i = 0; i < pe->amode_cnt; i++) {
+		for (j = 0; j < pe->svid_cnt; j++) {
+			if (pe->svids[j].svid == pe->amodes->fx[i].svid) {
+				/* TODO(tbroch) need more elaborate mode
+				   resolution */
+				pe->amodes[i].mode_caps = pe->svids[j].mode_vdo;
+				pe->amodes[i].amode = dfp_amode1;
+				break;
+			}
+		}
+	}
+}
 /****************************************************************************/
 /* Console commands */
 static int command_ec_int(int argc, char **argv)