Sometimes the hub driver does not recognize the USB device connected to the external USB2.0 hub when the system resumes from S4.

After the SetPortFeature(PORT_RESET) request is completed, the hub driver calls the HCD reset_device callback, which will issue a Reset Device command and free all structures associated with endpoints that were disabled.

This happens when the xHCI driver issue a Reset Device command to inform the Etron xHCI host that the USB device associated with a device slot has been reset. Seems that the Etron xHCI host can not perform this command correctly, affecting the USB device.

To work around this, the xHCI driver should obtain a new device slot with reference to commit 651aaf36a7d7 ("usb: xhci: Handle USB transaction error on address command"), which is another way to inform the Etron xHCI host that the USB device has been reset.

Add a new XHCI_ETRON_HOST quirk flag to invoke the workaround in xhci_discover_or_reset_device().

Fixes: 2a8f82c4ceaf ("USB: xhci: Notify the xHC when a device is reset.") Cc: stable@vger.kernel.org Signed-off-by: Kuangyi Chiang ki.chiang65@gmail.com --- drivers/usb/host/xhci-pci.c | 1 + drivers/usb/host/xhci.c | 19 +++++++++++++++++++ drivers/usb/host/xhci.h | 1 + 3 files changed, 21 insertions(+)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 33a6d99afc10..ddc9a82cceec 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -397,6 +397,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) if (pdev->vendor == PCI_VENDOR_ID_ETRON && (pdev->device == PCI_DEVICE_ID_EJ168 || pdev->device == PCI_DEVICE_ID_EJ188)) { + xhci->quirks |= XHCI_ETRON_HOST; xhci->quirks |= XHCI_RESET_ON_RESUME; xhci->quirks |= XHCI_BROKEN_STREAMS; } diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 899c0effb5d3..ef7ead6393d4 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3692,6 +3692,8 @@ void xhci_free_device_endpoint_resources(struct xhci_hcd *xhci, xhci->num_active_eps); }

+static void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev); + /* * This submits a Reset Device Command, which will set the device state to 0, * set the device address to 0, and disable all the endpoints except the default @@ -3762,6 +3764,23 @@ static int xhci_discover_or_reset_device(struct usb_hcd *hcd, SLOT_STATE_DISABLED) return 0;

+ if (xhci->quirks & XHCI_ETRON_HOST) { + /* + * Obtaining a new device slot to inform the xHCI host that + * the USB device has been reset. + */ + ret = xhci_disable_slot(xhci, udev->slot_id); + xhci_free_virt_device(xhci, udev->slot_id); + if (!ret) { + ret = xhci_alloc_dev(hcd, udev); + if (ret == 1) + ret = 0; + else + ret = -EINVAL; + } + return ret; + } + trace_xhci_discover_or_reset_device(slot_ctx);

xhci_dbg(xhci, "Resetting device with slot ID %u\n", slot_id); diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index f0fb696d5619..4f5b732e8944 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1624,6 +1624,7 @@ struct xhci_hcd { #define XHCI_ZHAOXIN_HOST BIT_ULL(46) #define XHCI_WRITE_64_HI_LO BIT_ULL(47) #define XHCI_CDNS_SCTX_QUIRK BIT_ULL(48) +#define XHCI_ETRON_HOST BIT_ULL(49)

unsigned int num_active_eps; unsigned int limit_active_eps;