disp: msm: dp: reset combo phy if peer_usb_comm is disabled

Some Type-C multi-port adapters which do not support usb connection
are advertising the multi-functionality in DP alt mode. If
multi-functionality is preferred, the DP driver assumes the adapter
supports usb connection and USB phy driver will program the PHY mode
to DP+USB.

In source mode, usb PD driver checks for the peer_usb_connection
of the adapter. If it does not support usb then it will stop usb stack
and update the PHY MODE to USB only mode from phy_suspend path.
The result is, usb may program the combo PHY to usb only mode when DP
is already connected. This is causing AUX read/write timeouts when DP
is trying to access the phy registers.

To fix this issue, a flag in SVID connect handler in usbpd driver to
notify peer_usb_comm support to the DP driver. DP driver will read this
flag and program the phy mode.

Change-Id: I0164b239bf2832d480795d90f5e9fc221bcc12ba
Signed-off-by: Sankeerth Billakanti <[email protected]>

msm/dp/dp_catalog.c

@@ -1349,6 +1349,7 @@ static void dp_catalog_ctrl_usb_reset(struct dp_catalog_ctrl *ctrl, bool flip)
 
 	io_data = catalog->io.usb3_dp_com;
 
+	DP_DEBUG("Program PHYMODE to DP only\n");
 	dp_write(USB3_DP_COM_RESET_OVRD_CTRL, 0x0a);
 	dp_write(USB3_DP_COM_PHY_MODE_CTRL, 0x02);
 	dp_write(USB3_DP_COM_SW_RESET, 0x01);

msm/dp/dp_display.c

@@ -781,7 +781,8 @@ static void dp_display_host_init(struct dp_display_private *dp)
 	if (dp->hpd->orientation == ORIENTATION_CC2)
 		flip = true;
 
-	reset = dp->debug->sim_mode ? false : !dp->hpd->multi_func;
+	reset = dp->debug->sim_mode ? false :
+		(!dp->hpd->multi_func || !dp->hpd->peer_usb_comm);
 
 	dp->power->init(dp->power, flip);
 	dp->hpd->host_init(dp->hpd, &dp->catalog->hpd);

msm/dp/dp_hpd.h

@@ -63,6 +63,7 @@ struct dp_hpd {
 	bool hpd_irq;
 	bool alt_mode_cfg_done;
 	bool multi_func;
+	bool peer_usb_comm;
 
 	void (*isr)(struct dp_hpd *dp_hpd);
 	int (*register_hpd)(struct dp_hpd *dp_hpd);

msm/dp/dp_usbpd.c

@@ -235,7 +235,8 @@ static void dp_usbpd_send_event(struct dp_usbpd_private *pd,
 	}
 }
 
-static void dp_usbpd_connect_cb(struct usbpd_svid_handler *hdlr)
+static void dp_usbpd_connect_cb(struct usbpd_svid_handler *hdlr,
+		bool peer_usb_comm)
 {
 	struct dp_usbpd_private *pd;
 
@@ -245,7 +246,8 @@ static void dp_usbpd_connect_cb(struct usbpd_svid_handler *hdlr)
 		return;
 	}
 
-	DP_DEBUG("\n");
+	DP_DEBUG("peer_usb_comm: %d\n");
+	pd->dp_usbpd.base.peer_usb_comm = peer_usb_comm;
 	dp_usbpd_send_event(pd, DP_USBPD_EVT_DISCOVER);
 }