On Fri, 2 Feb 2018, Peter Chen wrote: > On Thu, Feb 01, 2018 at 02:24:29PM -0500, Alan Stern wrote: > > On Thu, 1 Feb 2018, Peter Chen wrote: > > > > > At former code, the SETUP stage does not enable interrupt > > > for qtd completion, it relies on IAA watchdog to complete > > > interrupt, then the transcation would be considered timeout > > > if the flag need_io_watchdog is cleared by platform code. > > > > > > In this commit, we always add enable interrupt for qtd completion, > > > then the qtd completion can be notified by hardware interrupt. > > > > > > Signed-off-by: Peter Chen <peter.chen@xxxxxxx> > > > --- > > > drivers/usb/host/ehci-q.c | 6 +++--- > > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c > > > index 8815832..4cc2609 100644 > > > --- a/drivers/usb/host/ehci-q.c > > > +++ b/drivers/usb/host/ehci-q.c > > > @@ -1192,6 +1192,8 @@ static int submit_single_step_set_feature( > > > qtd_fill(ehci, qtd, urb->setup_dma, > > > sizeof(struct usb_ctrlrequest), > > > token | (2 /* "setup" */ << 8), 8); > > > + /* Always enable interrupt on qtd completion */ > > > + qtd->hw_token |= cpu_to_hc32(ehci, QTD_IOC); > > > > This would be cleaner if you didn't make it a separate statement. > > Before the call to qtd_fill(), you can do: > > > > token |= QTD_IOC; /* Interrupt after SETUP completion */ > > Since the variable "token" is used for every qtd, but I do not want > interrupt for DATA stage, how about adding QTD_IOC directly at > qtd_fill for both SETUP and STATUS stage? > > qtd_fill(ehci, qtd, urb->setup_dma, > sizeof(struct usb_ctrlrequest), > QTD_IOC | token | (2 /* "setup" */ << 8), 8); That would be okay. You might want to include a comment line as well. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
