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, 118 insertions, 1 deletions

diff --git a/board/hoho/usb_pd_policy.c b/board/hoho/usb_pd_policy.c
index 57099a960d..5523b2a95c 100644
--- a/board/hoho/usb_pd_policy.c
+++ b/board/hoho/usb_pd_policy.c
@@ -14,6 +14,7 @@
 #include "timer.h"
 #include "util.h"
 #include "usb_pd.h"
+#include "version.h"
 
 #define CPRINTS(format, args...) cprints(CC_USBPD, format, ## args)
 
@@ -23,7 +24,7 @@ const int pd_src_pdo_cnt = ARRAY_SIZE(pd_src_pdo);
 
 /* Fake PDOs : we just want our pre-defined voltages */
 const uint32_t pd_snk_pdo[] = {
-		PDO_FIXED(5000,   500, 0),
+		PDO_FIXED(5000, 500, 0),
 };
 const int pd_snk_pdo_cnt = ARRAY_SIZE(pd_snk_pdo);
 
@@ -88,3 +89,119 @@ int pd_board_checks(void)
 	return EC_SUCCESS;
 }
 
+/* ----------------- Vendor Defined Messages ------------------ */
+const uint32_t vdo_idh = VDO_IDH(0, /* data caps as USB host */
+				 0, /* data caps as USB device */
+				 IDH_PTYPE_AMA, /* Alternate mode */
+				 1, /* supports alt modes */
+				 USB_VID_GOOGLE);
+
+const uint32_t vdo_ama = VDO_AMA(CONFIG_USB_PD_IDENTITY_HW_VERS,
+				 CONFIG_USB_PD_IDENTITY_SW_VERS,
+				 0, 0, 0, 0, /* SS[TR][12] */
+				 0, /* Vconn power */
+				 0, /* Vconn power required */
+				 1, /* Vbus power required */
+				 0	 /* USB SS support */);
+
+static int svdm_response_identity(int port, uint32_t *payload)
+{
+	payload[VDO_I(IDH)] = vdo_idh;
+	/* TODO(tbroch): Do we plan to obtain TID (test ID) for hoho */
+	payload[VDO_I(CSTAT)] = VDO_CSTAT(0);
+	payload[VDO_I(AMA)] = vdo_ama;
+	return 4;
+}
+
+static int svdm_response_svids(int port, uint32_t *payload)
+{
+	payload[1] = VDO_SVID(USB_SID_DISPLAYPORT, 0);
+	return 2;
+}
+
+const uint32_t vdo_dp_mode[1] =  {
+	VDO_MODE_DP(MODE_DP_PIN_E, /* sink pin cfg */
+		    0,		   /* no src pin cfg */
+		    1,		   /* no usb2.0	signalling in AMode */
+		    CABLE_PLUG,	   /* its a plug */
+		    0,		   /* no GEN2 usb */
+		    0,		   /* no dp 1.3 support */
+		    MODE_DP_SNK)   /* Its a sink only */
+};
+
+static int svdm_response_modes(int port, uint32_t *payload)
+{
+	if (PD_VDO_VID(payload[0]) != USB_SID_DISPLAYPORT) {
+		/* TODO(tbroch) USB billboard enabled here then */
+		return 1; /* will generate a NAK */
+	}
+	memset(payload + 1, 0, sizeof(uint32_t) * PDO_MODES);
+	payload[1] = vdo_dp_mode[0];
+	/* TODO(tbroch) does spec have mechanism for identifying valid modes
+	 * returned for svid? */
+	return PDO_MAX_OBJECTS;
+}
+
+static int svdm_enter_mode(int port, uint32_t *payload)
+{
+	/* SID & mode request is valid */
+	if ((PD_VDO_VID(payload[0]) != USB_SID_DISPLAYPORT) ||
+	    (PD_VDO_OPOS(payload[0]) != 1))
+		return 1; /* will generate a NAK */
+
+	gpio_set_level(GPIO_PD_SBU_ENABLE, 1);
+	payload[1] = 0;
+	return 1;
+}
+
+static int svdm_exit_mode(int port, uint32_t *payload)
+{
+	/* SID & mode request is valid */
+	if ((PD_VDO_VID(payload[0]) != USB_SID_DISPLAYPORT) ||
+	    (PD_VDO_OPOS(payload[0]) != 1))
+		return 1; /* will generate a NAK */
+
+	gpio_set_level(GPIO_PD_SBU_ENABLE, 0);
+	payload[1] = 0;
+	return 1;
+}
+
+const struct svdm_response svdm_rsp = {
+	.identity = &svdm_response_identity,
+	.svids = &svdm_response_svids,
+	.modes = &svdm_response_modes,
+	.enter_mode = &svdm_enter_mode,
+	.exit_mode = &svdm_exit_mode,
+};
+
+static int pd_custom_vdm(int port, int cnt, uint32_t *payload,
+			 uint32_t **rpayload)
+{
+	int cmd = PD_VDO_CMD(payload[0]);
+	int rsize = 1;
+	ccprintf("%T] VDM/%d [%d] %08x\n", cnt, cmd, payload[0]);
+
+	*rpayload = payload;
+	switch (cmd) {
+	case VDO_CMD_VERSION:
+		memcpy(payload + 1, &version_data.version, 24);
+		rsize = 7;
+		break;
+	default:
+		/* Unknown : do not answer */
+		return 0;
+	}
+	ccprintf("%T] DONE\n");
+	/* respond (positively) to the request */
+	payload[0] |= VDO_SRC_RESPONDER;
+
+	return rsize;
+}
+
+int pd_vdm(int port, int cnt, uint32_t *payload, uint32_t **rpayload)
+{
+	if (PD_VDO_SVDM(payload[0]))
+		return pd_svdm(port, cnt, payload, rpayload);
+	else
+		return pd_custom_vdm(port, cnt, payload, rpayload);
+}