On Sun, Oct 11, 2020 at 09:50:08PM +0100, Sudip Mukherjee wrote: > Add a comment explaining why find_tt() will not return error even though > find_tt() is checking for NULL and other errors. > > Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx> > --- > drivers/usb/host/ehci-sched.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c > index 6dfb242f9a4b..0f85aa9b2fb1 100644 > --- a/drivers/usb/host/ehci-sched.c > +++ b/drivers/usb/host/ehci-sched.c > @@ -244,6 +244,12 @@ static void reserve_release_intr_bandwidth(struct ehci_hcd *ehci, > > /* FS/LS bus bandwidth */ > if (tt_usecs) { > + /* > + * find_tt() will not return any error here as we have > + * already called find_tt() before calling this function > + * and checked for any error return. The previous call > + * would have created the data structure. > + */ > tt = find_tt(qh->ps.udev); > if (sign > 0) > list_add_tail(&qh->ps.ps_list, &tt->ps_list); > @@ -1337,6 +1343,12 @@ static void reserve_release_iso_bandwidth(struct ehci_hcd *ehci, > } > } > > + /* > + * find_tt() will not return any error here as we have > + * already called find_tt() before calling this function > + * and checked for any error return. The previous call > + * would have created the data structure. > + */ > tt = find_tt(stream->ps.udev); > if (sign > 0) > list_add_tail(&stream->ps.ps_list, &tt->ps_list); Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>