On Fri, May 10, 2019 at 05:02:16PM +0800, Jim Lin wrote: > The Clear_TT_Buffer request sent to the hub includes the address of > the LS/FS child device in wValue field. usb_hub_clear_tt_buffer() > uses udev->devnum to set the address wValue. This won't work for > devices connected to xHC. > > For other host controllers udev->devnum is the same as the address of > the usb device, chosen and set by usb core. With xHC the controller > hardware assigns the address, and won't be the same as devnum. > > Here we add devaddr in "struct usb_device" for > usb_hub_clear_tt_buffer() to use. > > Signed-off-by: Jim Lin <jilin@xxxxxxxxxx> > --- > v2: xhci_clear_tt_buffer_complete: add static, shorter indentation > , remove its claiming in xhci.h > v3: Add description for clearing_tt (xhci.h) > v4: Remove clearing_tt flag because hub_tt_work has hub->tt.lock > to protect for Clear_TT_Buffer to be run serially. > Remove xhci_clear_tt_buffer_complete as it's not necessary. > Same reason as the above. > Extend usb_hub_clear_tt_buffer parameter > v5: Not extending usb_hub_clear_tt_buffer parameter > Add description. > v6: Remove unused parameter slot_id from xhci_clear_hub_tt_buffer > v7: Add devaddr field in "struct usb_device" > v8: split as two patches, change type from int to u8 for devaddr. > > drivers/usb/core/hub.c | 4 +++- > include/linux/usb.h | 2 ++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c > index 15a2934dc29d..078894023797 100644 > --- a/drivers/usb/core/hub.c > +++ b/drivers/usb/core/hub.c > @@ -873,7 +873,7 @@ int usb_hub_clear_tt_buffer(struct urb *urb) > /* info that CLEAR_TT_BUFFER needs */ > clear->tt = tt->multi ? udev->ttport : 1; > clear->devinfo = usb_pipeendpoint (pipe); > - clear->devinfo |= udev->devnum << 4; > + clear->devinfo |= (u16) (udev->devaddr << 4); > clear->devinfo |= usb_pipecontrol(pipe) > ? (USB_ENDPOINT_XFER_CONTROL << 11) > : (USB_ENDPOINT_XFER_BULK << 11); > @@ -2125,6 +2125,8 @@ static void update_devnum(struct usb_device *udev, int devnum) > /* The address for a WUSB device is managed by wusbcore. */ > if (!udev->wusb) > udev->devnum = devnum; > + if (!udev->devaddr) > + udev->devaddr = (u8) devnum; Checkpatch did not complain here? Or above? Please don't put a space before the ) when casting. > } > > static void hub_free_dev(struct usb_device *udev) > diff --git a/include/linux/usb.h b/include/linux/usb.h > index 4229eb74bd2c..db38c13a6b1d 100644 > --- a/include/linux/usb.h > +++ b/include/linux/usb.h > @@ -565,6 +565,7 @@ struct usb3_lpm_parameters { > * @tx_lanes: number of tx lanes in use, USB 3.2 adds dual-lane support > * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub > * @ttport: device port on that tt hub > + * @devaddr: device address, XHCI: assigned by HW, others: same as devnum > * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints > * @parent: our hub, unless we're the root > * @bus: bus we're part of > @@ -641,6 +642,7 @@ struct usb_device { > > struct usb_tt *tt; > int ttport; > + u8 devaddr; That's some horrible variable alignment :( Please use pahole to find a better place to put it. thanks, greg k-h