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

From: Frank Li
Date: Wed Oct 26 2022 - 15:10:53 EST


From: Li Jun <jun.li@xxxxxxx>

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@xxxxxxxxxxxxxxx 5.10
Signed-off-by: Li Jun <jun.li@xxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---

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