phy: qcom: qmp-combo: Select LFPS detect only when SS link is confirm…

drivers/phy/qualcomm/phy-qcom-qmp-combo.c

@@ -25,6 +25,7 @@
 #include <drm/bridge/aux-bridge.h>
 
 #include <dt-bindings/phy/phy-qcom-qmp.h>
+#include <linux/phy/phy-qcom-qmp-usb-ss.h>
 
 #include "phy-qcom-qmp-common.h"
 
@@ -2275,6 +2276,7 @@ struct qmp_combo {
 
 	struct phy *usb_phy;
 	enum phy_mode phy_mode;
+	enum qcom_usb_ss_state  ss_state;
 	unsigned int usb_init_count;
 
 	struct phy *dp_phy;
@@ -3929,6 +3931,16 @@ static int qmp_combo_usb_set_mode(struct phy *phy, enum phy_mode mode, int submo
 
 	qmp->phy_mode = mode;
 
+	switch (submode) {
+		case QCOM_USB_SS_PRESENT:
+		case QCOM_USB_SS_ABSENT:
+			qmp->ss_state = submode;
+			break;
+		default:
+			qmp->ss_state = QCOM_USB_SS_UNKNOWN;
+			break;
+	}
+
 	return 0;
 }
 
@@ -3957,11 +3969,20 @@ static void qmp_combo_enable_autonomous_mode(struct qmp_combo *qmp)
 	void __iomem *pcs_aon = qmp->pcs_aon;
 	u32 intr_mask;
 
-	if (qmp->phy_mode == PHY_MODE_USB_HOST_SS ||
-	    qmp->phy_mode == PHY_MODE_USB_DEVICE_SS)
-		intr_mask = ARCVR_DTCT_EN | ALFPS_DTCT_EN;
-	else
-		intr_mask = ARCVR_DTCT_EN | ARCVR_DTCT_EVENT_SEL;
+	/*
+	* Use LFPS detection only when a SuperSpeed device is known to be
+	* present. For absent or unknown state, use receiver detection.
+	*/
+	switch (qmp->ss_state) {
+		case QCOM_USB_SS_PRESENT:
+			intr_mask = ARCVR_DTCT_EN | ALFPS_DTCT_EN;
+			break;
+		case QCOM_USB_SS_ABSENT:
+		case QCOM_USB_SS_UNKNOWN:
+		default:
+			intr_mask = ARCVR_DTCT_EN | ARCVR_DTCT_EVENT_SEL;
+			break;
+	}
 
 	/* Clear any pending interrupts status */
 	qphy_setbits(pcs_usb, cfg->regs[QPHY_PCS_LFPS_RXTERM_IRQ_CLEAR], IRQ_CLEAR);

drivers/usb/dwc3/dwc3-qcom.c

@@ -20,6 +20,7 @@
 #include <linux/usb/hcd.h>
 #include <linux/pm_domain.h>
 #include <linux/usb.h>
+#include <linux/phy/phy-qcom-qmp-usb-ss.h>
 #include "core.h"
 #include "glue.h"
 
@@ -67,6 +68,7 @@ struct dwc3_qcom_port {
 	int			dm_hs_phy_irq;
 	int			ss_phy_irq;
 	enum usb_device_speed	usb2_speed;
+	enum qcom_usb_ss_state  ss_state;
 };
 
 struct dwc3_qcom {
@@ -252,6 +254,32 @@ static enum usb_device_speed dwc3_qcom_read_usb2_speed(struct dwc3_qcom *qcom, i
 	return udev->speed;
 }
 
+static enum qcom_usb_ss_state dwc3_qcom_read_ss_state(struct dwc3_qcom *qcom, int port_index)
+{
+       struct usb_device *udev;
+       struct usb_hcd __maybe_unused *hcd, *usb3_hcd;
+       struct dwc3 *dwc = &qcom->dwc;
+
+       /* FIXME: Fix this layering violation. */
+       hcd = platform_get_drvdata(dwc->xhci);
+       if (!hcd)
+                return QCOM_USB_SS_ABSENT;
+
+#ifdef CONFIG_USB
+       usb3_hcd = hcd->shared_hcd ? hcd->shared_hcd : hcd;
+       if (!usb3_hcd->self.root_hub)
+                return QCOM_USB_SS_ABSENT;
+
+       udev = usb_hub_find_child(usb3_hcd->self.root_hub, port_index + 1);
+#else
+       udev = NULL;
+#endif
+       if (!udev)
+               return QCOM_USB_SS_ABSENT;
+
+       return udev->speed >= USB_SPEED_SUPER ? QCOM_USB_SS_PRESENT : QCOM_USB_SS_ABSENT;
+}
+
 static void dwc3_qcom_enable_wakeup_irq(int irq, unsigned int polarity)
 {
 	if (!irq)
@@ -360,8 +388,13 @@ static int dwc3_qcom_suspend(struct dwc3_qcom *qcom, bool wakeup)
 	 * freezable workqueue.
 	 */
 	if (dwc3_qcom_is_host(qcom) && wakeup) {
-		for (i = 0; i < qcom->num_ports; i++)
+		for (i = 0; i < qcom->num_ports; i++){
 			qcom->ports[i].usb2_speed = dwc3_qcom_read_usb2_speed(qcom, i);
+			qcom->ports[i].ss_state = dwc3_qcom_read_ss_state(qcom, i);
+			phy_set_mode_ext(qcom->dwc.usb3_generic_phy[i], PHY_MODE_USB_HOST,
+                                       qcom->ports[i].ss_state);
+
+		}
 		dwc3_qcom_enable_interrupts(qcom);
 	} else {
 		dev_pm_genpd_synced_poweroff(qcom->dev);

include/linux/phy/phy-qcom-qmp-usb-ss.h

@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Shared submode contract between dwc3-qcom glue and the Qualcomm QMP
+ * USB3/combo PHY driver for communicating live SuperSpeed link presence
+ * at suspend-entry, via phy_set_mode_ext()'s submode argument.
+ */
+
+#ifndef _PHY_QCOM_QMP_USB_SS_H_
+#define _PHY_QCOM_QMP_USB_SS_H_
+
+enum qcom_usb_ss_state {
+	QCOM_USB_SS_UNKNOWN = 0,
+	QCOM_USB_SS_PRESENT,
+	QCOM_USB_SS_ABSENT,
+};
+
+#endif /* _PHY_QCOM_QMP_USB_SS_H_ */