pd: VDM Alternate mode support.

Successfully communicate SVDM for discovery (identity, svids, modes)
and enter mode.

Still need to:
- Add same functionality on when power role is sink too.
- determine what connected events would require exit mode.
- do proper cleanup on disconnect.
- implement real display port 'enter' mode for samus_pd
- test & cleanup

Additionally the USB Billboard class functionality needs to be added
but will likely do that in a separate CL.

BRANCH=none
BUG=chrome-os-partner:28342
TEST=manual,

From fruitpie,
    [Image: RO, fruitpie_v1.1.2263-d79140d-dirty 2014-09-29 17:44:15 tbroch@brisket.mtv.corp.google.com]
    [0.000383 Inits done]
    C0 st2
    Console is enabled; type HELP for help.
    > [0.250551 USB PD initialized]
    pd dualrole source
    C0 st8
    > [8.366335 PD TMOUT RX 1/1]
    RX ERR (-1)
    [8.478308 PD TMOUT RX 1/1]
    RX ERR (-1)
    [8.590280 PD TMOUT RX 1/1]
    RX ERR (-1)
    C0 st9
    Switch to 5000 V 3000 mA (for 3000/3000 mA)
    C0 st10
    C0 st11
    C0 st12
    8.867593] SVDM/4 [1] ff008081 340018d1 00000000 17000008
    8.867906] DONE
    8.871006] SVDM/2 [2] ff008082 ff010000
    8.871224] DONE
    8.875092] SVDM/7 [3] ff018083 00100081 00000000 00000000 00000000 00000000 00000000
    Entering mode w/ vdo = 00100081
    8.875492] DONE
    8.878435] SVDM/1 [4] ff018144
    8.878612] DONE

    > pe 0 dump
    SVID[0]: ff01 [0] 00100081 [1] 00000000 [2] 00000000 [3] 00000000 [4] 00000000 [5] 00000000
    MODE[0]: svid:ff01 mode:1 caps:00100081

From hoho,
    [Image: RO, hoho_v1.1.2263-d79140d-dirty 2014-09-29 17:54:59 tbroch@brisket.mtv.corp.google.com]
    [0.000375 Inits done]
    C0 st2
    Console is enabled; type HELP for help.
    > [0.250542 USB PD initialized]
    C0 st3
    [0.264637 PD TMOUT RX 1/1]
    RX ERR (-1)
    Request [1] 5V 3000mA
    C0 st4
    C0 st5
    C0 st6
    0.487451] SVDM/1 [1] ff008001
    0.487628] DONE
    0.491190] SVDM/1 [2] ff008002
    0.491346] DONE
    0.494510] SVDM/1 [3] ff018003
    0.494667] DONE
    0.498777] SVDM/1 [4] ff018104
    0.498934] DONE

Change-Id: I5e2b7802c66b8aaad97e5120dca7a02820086bc1
Signed-off-by: Todd Broch <tbroch@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/219513
Reviewed-by: Alec Berg <alecaberg@chromium.org>

1 files changed, 28 insertions, 27 deletions

diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index a5a272ab2d..1e7641ed56 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -151,6 +151,7 @@ static const uint8_t dec4b5b[] = {
 #define CC_RA(cc)  (cc < PD_SRC_RD_THRESHOLD)
 #define CC_RD(cc) ((cc > PD_SRC_RD_THRESHOLD) && (cc < PD_SRC_VNC))
 #define GET_POLARITY(cc1, cc2) (CC_RD(cc2) || CC_RA(cc1))
+#define IS_CABLE(cc1, cc2)     (CC_RD(cc1) || CC_RD(cc2))
 
 /* PD counter definitions */
 #define PD_MESSAGE_ID_COUNT 7
@@ -619,29 +620,23 @@ static void bist_mode_2_rx(int port)
 
 static void handle_vdm_request(int port, int cnt, uint32_t *payload)
 {
-	uint16_t vid = PD_VDO_VID(payload[0]);
-#ifdef CONFIG_USB_PD_CUSTOM_VDM
-	int rlen;
+	int rlen = 0;
 	uint32_t *rdata;
-#endif
 
-	if (vid == USB_VID_GOOGLE) {
-		if (pd[port].vdm_state == VDM_STATE_BUSY)
-			pd[port].vdm_state = VDM_STATE_DONE;
-#ifdef CONFIG_USB_PD_CUSTOM_VDM
-		rlen = pd_custom_vdm(port, cnt, payload, &rdata);
-		if (rlen > 0) {
-			uint16_t header = PD_HEADER(PD_DATA_VENDOR_DEF,
-						pd[port].role, pd[port].msg_id,
-						rlen);
-			send_validate_message(port, header, rlen, rdata);
-		}
-#endif
+	if (pd[port].vdm_state == VDM_STATE_BUSY)
+		pd[port].vdm_state = VDM_STATE_DONE;
+
+	rlen = pd_vdm(port, cnt, payload, &rdata);
+	if (rlen > 0) {
+		uint16_t header = PD_HEADER(PD_DATA_VENDOR_DEF,
+					    pd[port].role, pd[port].msg_id,
+					    rlen);
+		send_validate_message(port, header, rlen, rdata);
 		return;
 	}
 	if (debug_level >= 1)
 		CPRINTF("Unhandled VDM VID %04x CMD %04x\n",
-			vid, payload[0] & 0xFFFF);
+			PD_VDO_VID(payload[0]), payload[0] & 0xFFFF);
 }
 
 static void execute_hard_reset(int port)
@@ -1027,7 +1022,7 @@ void pd_send_vdm(int port, uint32_t vid, int cmd, const uint32_t *data,
 		return;
 	}
 
-	pd[port].vdo_data[0] = VDO(vid, cmd);
+	pd[port].vdo_data[0] = VDO(vid, (vid == USB_SID_PD) ? 1 : 0, cmd);
 	pd[port].vdo_count = count + 1;
 	for (i = 1; i < count + 1; i++)
 		pd[port].vdo_data[i] = data[i-1];
@@ -1319,20 +1314,23 @@ void pd_task(void)
 			}
 			break;
 		case PD_STATE_SRC_READY:
-#ifdef CONFIG_USB_PD_SIMPLE_DFP
-			/*
-			 * For simple devices that don't support alternate
-			 * mode and are only sources (ie power adapters),
-			 * send custom VDM with info about this device
-			 * once power contract has been negotiated.
-			 */
 			if (pd[port].last_state != pd[port].task_state) {
-				/* Send google VDM to read info */
+#ifdef CONFIG_USB_PD_SIMPLE_DFP
+				/*
+				 * For simple devices that don't support
+				 * alternate mode and are only sources (ie power
+				 * adapters), send custom VDM with info about
+				 * this device once power contract has been
+				 * negotiated.
+				 */
 				pd_send_vdm(port, USB_VID_GOOGLE,
 					    VDO_CMD_SEND_INFO,
 					    pd_get_info(), 6);
-			}
+#else
+				pd_send_vdm(port, USB_SID_PD,
+					    CMD_DISCOVER_IDENT, NULL, 0);
 #endif
+			}
 
 			if (!pd[port].ping_enabled) {
 				timeout = PD_T_SOURCE_ACTIVITY;
@@ -1443,6 +1441,7 @@ void pd_task(void)
 					PD_STATE_HARD_RESET);
 			break;
 		case PD_STATE_HARD_RESET:
+			pd_exit_modes(port, payload);
 			send_hard_reset(port);
 			/* reset our own state machine */
 			execute_hard_reset(port);
@@ -1797,8 +1796,10 @@ static int command_pd(int argc, char **argv)
 	} else if (!strncasecmp(argv[2], "state", 5)) {
 		const char * const state_names[] = {
 			"DISABLED", "SUSPENDED",
+#ifdef CONFIG_USB_PD_DUAL_ROLE
 			"SNK_DISCONNECTED", "SNK_DISCOVERY", "SNK_REQUESTED",
 			"SNK_TRANSITION", "SNK_READY",
+#endif /* CONFIG_USB_PD_DUAL_ROLE */
 			"SRC_DISCONNECTED", "SRC_DISCOVERY", "SRC_NEGOCIATE",
 			"SRC_ACCEPTED", "SRC_TRANSITION", "SRC_READY",
 			"SOFT_RESET", "HARD_RESET", "BIST",