On Sat, Oct 30, 2021 at 12:49:37PM +0800, Walt Jr. Brake wrote: > This patch make USB 3.1 device cannot be detected, and I report the bug [1] > to archlinux three month ago. Yesterday I try to fix it myself, and after I > revert this patch, compile the kernel and test, it works. > > [1] https://bugs.archlinux.org/task/71660?project=1&pagenum=2 > > > diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h > index 22ea1f4f2d66..73f4482d833a 100644 > --- a/drivers/usb/core/hub.h > +++ b/drivers/usb/core/hub.h > @@ -148,10 +148,8 @@ static inline unsigned hub_power_on_good_delay(struct > usb_hub *hub) > { > unsigned delay = hub->descriptor->bPwrOn2PwrGood * 2; > > - if (!hub->hdev->parent) /* root hub */ > - return delay; > - else /* Wait at least 100 msec for power to become stable */ > - return max(delay, 100U); > + /* Wait at least 100 msec for power to become stable */ > + return max(delay, 100U); > } Mathias: It looks like the bPwrOn2PwrGood value in xhci-hcd's hub descriptor is too small for some USB 3.1 devices. Can you look into this? Alan Stern > On 10/4/2021 09:20, Chunfeng Yun wrote: > > Return the exactly delay time given by root hub descriptor, > > this helps to reduce resume time etc. > > > > Due to the root hub descriptor is usually provided by the host > > controller driver, if there is compatibility for a root hub, > > we can fix it easily without affect other root hub > > > > Acked-by: Alan Stern<stern@xxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Chunfeng Yun<chunfeng.yun@xxxxxxxxxxxx> > > --- > > v2: remove RFC tag, and add acked-by Alan > > --- > > drivers/usb/core/hub.h | 6 ++++-- > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h > > index 73f4482d833a..22ea1f4f2d66 100644 > > --- a/drivers/usb/core/hub.h > > +++ b/drivers/usb/core/hub.h > > @@ -148,8 +148,10 @@ static inline unsigned hub_power_on_good_delay(struct usb_hub *hub) > > { > > unsigned delay = hub->descriptor->bPwrOn2PwrGood * 2; > > - /* Wait at least 100 msec for power to become stable */ > > - return max(delay, 100U); > > + if (!hub->hdev->parent) /* root hub */ > > + return delay; > > + else /* Wait at least 100 msec for power to become stable */ > > + return max(delay, 100U); > > } > > static inline int hub_port_debounce_be_connected(struct usb_hub *hub,
