usb: dwc3: add rx_detect to polling lfps quirk

This patch adds RX_DETECT to Polling.LFPS control quirk, and some special
platforms can configure that if it is needed.

[ balbi@ti.com : added DeviceTree binding documentation ]

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 29a7da0..b440b2b 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -389,6 +389,9 @@
 	if (dwc->lfps_filter_quirk)
 		reg |= DWC3_GUSB3PIPECTL_LFPSFILT;
 
+	if (dwc->rx_detect_poll_quirk)
+		reg |= DWC3_GUSB3PIPECTL_RX_DETOPOLL;
+
 	dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
 
 	mdelay(100);
@@ -776,6 +779,8 @@
 				"snps,del_phy_power_chg_quirk");
 		dwc->lfps_filter_quirk = of_property_read_bool(node,
 				"snps,lfps_filter_quirk");
+		dwc->rx_detect_poll_quirk = of_property_read_bool(node,
+				"snps,rx_detect_poll_quirk");
 	} else if (pdata) {
 		dwc->maximum_speed = pdata->maximum_speed;
 		dwc->has_lpm_erratum = pdata->has_lpm_erratum;
@@ -792,6 +797,7 @@
 		dwc->del_p1p2p3_quirk = pdata->del_p1p2p3_quirk;
 		dwc->del_phy_power_chg_quirk = pdata->del_phy_power_chg_quirk;
 		dwc->lfps_filter_quirk = pdata->lfps_filter_quirk;
+		dwc->rx_detect_poll_quirk = pdata->rx_detect_poll_quirk;
 	}
 
 	/* default to superspeed if no maximum_speed passed */