[PATCH v2 1/1] usb: cdns3: host: fix endless superspeed hub port reset

[Frank Li <Frank.Li@nxp.com>]

From: Li Jun <jun.li@nxp.com>

When usb 3.0 hub connect with one USB 2.0 device and NO USB 3.0 device,
some usb hub reports endless port reset message.

[  190.324169] usb 2-1: new SuperSpeed USB device number 88 using xhci-hcd
[  190.352834] hub 2-1:1.0: USB hub found
[  190.356995] hub 2-1:1.0: 4 ports detected
[  190.700056] usb 2-1: USB disconnect, device number 88
[  192.472139] usb 2-1: new SuperSpeed USB device number 89 using xhci-hcd
[  192.500820] hub 2-1:1.0: USB hub found
[  192.504977] hub 2-1:1.0: 4 ports detected
[  192.852066] usb 2-1: USB disconnect, device number 89

The reason is the runtime pm state of USB2.0 port is active and
USB 3.0 port is suspend, so parent device is active state.

 cat /sys/bus/platform/devices/5b110000.usb/5b130000.usb/xhci-hcd.1.auto/usb2/power/runtime_status

 suspended

 cat /sys/bus/platform/devices/5b110000.usb/5b130000.usb/xhci-hcd.1.auto/usb1/power/runtime_status

 active

 cat /sys/bus/platform/devices/5b110000.usb/5b130000.usb/xhci-hcd.1.auto/power/runtime_status

 active

 cat /sys/bus/platform/devices/5b110000.usb/5b130000.usb/power/runtime_status

 active

So xhci_cdns3_suspend_quirk() have not called. U3 configure is not applied.

move U3 configure into host start. Reinit again in resume function in case
controller power lost during suspend.

Cc: stable@vger.kernel.org 5.10
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---

Change from V1 to V2. 
 - call xhci_cdns3_plat_start() in xhci_cdns3_resume_quirk
in case power lost during suspend

 drivers/usb/cdns3/host.c | 56 ++++++++++++++++++++--------------------
 1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c
index 9643b905e2d8..6164fc4c96a4 100644
--- a/drivers/usb/cdns3/host.c
+++ b/drivers/usb/cdns3/host.c
@@ -24,11 +24,37 @@
 #define CFG_RXDET_P3_EN		BIT(15)
 #define LPM_2_STB_SWITCH_EN	BIT(25)
 
-static int xhci_cdns3_suspend_quirk(struct usb_hcd *hcd);
+static void xhci_cdns3_plat_start(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	u32 value;
+
+	/* set usbcmd.EU3S */
+	value = readl(&xhci->op_regs->command);
+	value |= CMD_PM_INDEX;
+	writel(value, &xhci->op_regs->command);
+
+	if (hcd->regs) {
+		value = readl(hcd->regs + XECP_AUX_CTRL_REG1);
+		value |= CFG_RXDET_P3_EN;
+		writel(value, hcd->regs + XECP_AUX_CTRL_REG1);
+
+		value = readl(hcd->regs + XECP_PORT_CAP_REG);
+		value |= LPM_2_STB_SWITCH_EN;
+		writel(value, hcd->regs + XECP_PORT_CAP_REG);
+	}
+}
+
+static int xhci_cdns3_resume_quirk(struct usb_hcd *hcd)
+{
+	xhci_cdns3_plat_start(hcd);
+	return 0;
+}
 
 static const struct xhci_plat_priv xhci_plat_cdns3_xhci = {
 	.quirks = XHCI_SKIP_PHY_INIT | XHCI_AVOID_BEI,
-	.suspend_quirk = xhci_cdns3_suspend_quirk,
+	.plat_start = xhci_cdns3_plat_start,
+	.resume_quirk = xhci_cdns3_resume_quirk,
 };
 
 static int __cdns_host_init(struct cdns *cdns)
@@ -90,32 +116,6 @@ static int __cdns_host_init(struct cdns *cdns)
 	return ret;
 }
 
-static int xhci_cdns3_suspend_quirk(struct usb_hcd *hcd)
-{
-	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
-	u32 value;
-
-	if (pm_runtime_status_suspended(hcd->self.controller))
-		return 0;
-
-	/* set usbcmd.EU3S */
-	value = readl(&xhci->op_regs->command);
-	value |= CMD_PM_INDEX;
-	writel(value, &xhci->op_regs->command);
-
-	if (hcd->regs) {
-		value = readl(hcd->regs + XECP_AUX_CTRL_REG1);
-		value |= CFG_RXDET_P3_EN;
-		writel(value, hcd->regs + XECP_AUX_CTRL_REG1);
-
-		value = readl(hcd->regs + XECP_PORT_CAP_REG);
-		value |= LPM_2_STB_SWITCH_EN;
-		writel(value, hcd->regs + XECP_PORT_CAP_REG);
-	}
-
-	return 0;
-}
-
 static void cdns_host_exit(struct cdns *cdns)
 {
 	kfree(cdns->xhci_plat_data);
-- 
2.34.1