From 5a71fa1a1025690adb47946f3f5b8f04319ed665 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Fri, 5 Nov 2021 18:00:36 +0200 Subject: [PATCH] xhci: Fix USB 3.1 enumeration issues by increasing roothub power-on-good delay commit e1959faf085b004e6c3afaaaa743381f00e7c015 upstream. Some USB 3.1 enumeration issues were reported after the hub driver removed the minimum 100ms limit for the power-on-good delay. Since commit 90d28fb53d4a ("usb: core: reduce power-on-good delay time of root hub") the hub driver sets the power-on-delay based on the bPwrOn2PwrGood value in the hub descriptor. xhci driver has a 20ms bPwrOn2PwrGood value for both roothubs based on xhci spec section 5.4.8, but it's clearly not enough for the USB 3.1 devices, causing enumeration issues. Tests indicate full 100ms delay is needed. Reported-by: Walt Jr. Brake Signed-off-by: Mathias Nyman Fixes: 90d28fb53d4a ("usb: core: reduce power-on-good delay time of root hub") Cc: stable Link: https://lore.kernel.org/r/20211105160036.549516-1-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index a3f875e..af946c4 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -257,7 +257,6 @@ static void xhci_common_hub_descriptor(struct xhci_hcd *xhci, { u16 temp; - desc->bPwrOn2PwrGood = 10; /* xhci section 5.4.9 says 20ms max */ desc->bHubContrCurrent = 0; desc->bNbrPorts = ports; @@ -292,6 +291,7 @@ static void xhci_usb2_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci, desc->bDescriptorType = USB_DT_HUB; temp = 1 + (ports / 8); desc->bDescLength = USB_DT_HUB_NONVAR_SIZE + 2 * temp; + desc->bPwrOn2PwrGood = 10; /* xhci section 5.4.8 says 20ms */ /* The Device Removable bits are reported on a byte granularity. * If the port doesn't exist within that byte, the bit is set to 0. @@ -344,6 +344,7 @@ static void xhci_usb3_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci, xhci_common_hub_descriptor(xhci, desc, ports); desc->bDescriptorType = USB_DT_SS_HUB; desc->bDescLength = USB_DT_SS_HUB_SIZE; + desc->bPwrOn2PwrGood = 50; /* usb 3.1 may fail if less than 100ms */ /* header decode latency should be zero for roothubs, * see section 4.23.5.2. -- 2.7.4