[PATCH v8 2/6] usb: host: xhci: plat: Add suspend quirk for dwc3 controller

[Sandeep Maheswaram]

During suspend read the status of all port and make sure the PHYs
are in the correct mode based on current speed.
Phy interrupt masks are set based on this mode. Keep track of the mode
of the HS PHY to be able to configure wakeup properly.

Also check during suspend if any wakeup capable devices are
connected to the controller (directly or through hubs), if there
are none set a flag to indicate that the PHY should be powered
down during suspend.

Signed-off-by: Sandeep Maheswaram <sanm@xxxxxxxxxxxxxx>
---
 drivers/usb/host/xhci-plat.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index c1edcc9..ee87923 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -24,6 +24,7 @@
 #include "xhci-plat.h"
 #include "xhci-mvebu.h"
 #include "xhci-rcar.h"
+#include "../dwc3/core.h"
 
 static struct hc_driver __read_mostly xhci_plat_hc_driver;
 
@@ -430,6 +431,39 @@ static int xhci_plat_remove(struct platform_device *dev)
 
 	return 0;
 }
+static void xhci_dwc3_suspend_quirk(struct usb_hcd *hcd)
+{
+	int i, num_ports;
+	u32 reg;
+	unsigned int ss_phy_mode = 0;
+	struct dwc3 *dwc = dev_get_drvdata(hcd->self.controller->parent);
+	struct xhci_hcd	*xhci_hcd = hcd_to_xhci(hcd);
+
+	dwc->hs_phy_mode = 0;
+
+	reg = readl(&xhci_hcd->cap_regs->hcs_params1);
+	num_ports = HCS_MAX_PORTS(reg);
+
+	for (i = 0; i < num_ports; i++) {
+		reg = readl(&xhci_hcd->op_regs->port_status_base + i * 0x04);
+		if (reg & PORT_PE) {
+			if (DEV_HIGHSPEED(reg) || DEV_FULLSPEED(reg))
+				dwc->hs_phy_mode |= PHY_MODE_USB_HOST_HS;
+			else if (DEV_LOWSPEED(reg))
+				dwc->hs_phy_mode |= PHY_MODE_USB_HOST_LS;
+
+			if (DEV_SUPERSPEED(reg))
+				ss_phy_mode |= PHY_MODE_USB_HOST_SS;
+		}
+	}
+	phy_set_mode(dwc->usb2_generic_phy, dwc->hs_phy_mode);
+	phy_set_mode(dwc->usb3_generic_phy, ss_phy_mode);
+
+	if (usb_wakeup_enabled_descendants(hcd->self.root_hub))
+		dwc->phy_power_off = false;
+	else
+		dwc->phy_power_off = true;
+}
 
 static int __maybe_unused xhci_plat_suspend(struct device *dev)
 {
@@ -440,6 +474,10 @@ static int __maybe_unused xhci_plat_suspend(struct device *dev)
 	ret = xhci_priv_suspend_quirk(hcd);
 	if (ret)
 		return ret;
+
+	if (of_device_is_compatible(dev->parent->of_node, "snps,dwc3"))
+		xhci_dwc3_suspend_quirk(hcd);
+
 	/*
 	 * xhci_suspend() needs `do_wakeup` to know whether host is allowed
 	 * to do wakeup during suspend.
-- 
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