Hi, > -----Original Message----- > From: Cliff Cai [mailto:cliffcai.sh@xxxxxxxxx] > Sent: Tuesday, May 18, 2010 1:51 PM > To: Gupta, Ajay Kumar > Cc: Cai, Cliff; linux-usb@xxxxxxxxxxxxxxx; Mike Frysinger; Felipe Balbi; > uclinux-dist-devel@xxxxxxxxxxxxxxxxxxxx > Subject: Re: [Uclinux-dist-devel] [PATCH] USB: musb: set NAK limitation > for control transfers > > On Tue, May 18, 2010 at 2:00 PM, Gupta, Ajay Kumar <ajay.gupta@xxxxxx> > wrote: > > Hi, > >> > Dose this patch work for you? > >> > I tried several different values,and > >> > It seems that '8' work just fine. > >> Yes, it works for me. > >> > >> I was just thinking of setting limit values based on device speed > >> so that timeout value in terms of msec is same for all devices. > >> For HS devices = 8, and for FS/LS devices = 5 for timeout of 16msec. > >> > >> - interval = 8; > >> + interval = (USB_SPEED_HIGH == urb->dev->speed) ? 8 : 5; > > > > Another fix (I think a better one) is to disable PING on status phase > > only, which is allowed as per USB specification. > > > > -------------- > > diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c > > index 83f482e..f1a3ca7 100644 > > --- a/drivers/usb/musb/musb_host.c > > +++ b/drivers/usb/musb/musb_host.c > > @@ -1068,6 +1068,8 @@ irqreturn_t musb_h_ep0_irq(struct musb *musb) > > else > > csr = MUSB_CSR0_H_STATUSPKT > > | MUSB_CSR0_TXPKTRDY; > > + /* disable ping token in status phase */ > > + csr |= MUSB_CSR0_H_DIS_PING; > > > > /* flag status stage */ > > musb->ep0_stage = MUSB_EP0_STATUS; > > -------------- > > > I got endless massages: "musb_h_ep0_irq 1053: no URB for end 0" with this > patch. Then your device doesn't seem to have PING issue. I also noticed this error message two times with your fix. > also I think disabling PING for all devices doesn't make sense. It's only for control endpoint and in status phase alone. > > while "interval = (USB_SPEED_HIGH == urb->dev->speed) ? 8 : 5;" > works for me. I think this should be fine to go. > > Thanks > > Cliff > > >> > >> > >-----Original Message----- > >> > >From: Mike Frysinger [mailto:vapier.adi@xxxxxxxxx] > >> > >Sent: Sunday, May 16, 2010 8:47 AM > >> > >To: Gupta, Ajay Kumar > >> > >Cc: linux-usb@xxxxxxxxxxxxxxx; Felipe Balbi; > >> > >uclinux-dist-devel@xxxxxxxxxxxxxxxxxxxx; Cai, Cliff > >> > >Subject: Re: [Uclinux-dist-devel] [PATCH] USB: musb: set NAK > >> > >limitation for control transfers > >> > > > >> > >On Fri, May 14, 2010 at 01:42, Gupta, Ajay Kumar wrote: > >> > >>> Some bad-behaved peripherals (like cheap USB storage devices) > need > >> > >>> this in order to recover during configuration time. > >> > >>> > >> > >>> diff --git a/drivers/usb/musb/musb_host.c > >> > >>> b/drivers/usb/musb/musb_host.c index 877d20b..e2667dc 100644 > >> > >>> --- a/drivers/usb/musb/musb_host.c > >> > >>> +++ b/drivers/usb/musb/musb_host.c > >> > >>> @@ -1994,6 +1994,9 @@ static int musb_urb_enqueue( > >> > >>> /* ISO always uses logarithmic encoding */ > >> > >>> interval = min_t(u8, epd->bInterval, 16); > >> > >>> break; > >> > >>> + case USB_ENDPOINT_XFER_CONTROL: > >> > >>> + interval = 8; > >> > >> > >> > >> Why '8'? Device could be high speed or FS/LS so it comes out to, > HS > >> > >> device: 2^7 uf = 128uf = 16 msec FS/LS device: 2^7 f = 128msec > >> > > > >> > >it's a value that seems to work in our tests. i'm pretty sure > >> > >we arent tied to a specific value, so if you want to increase > >> > >it, that's fine. Cliff can certainly correct me though. > >> > > > >> > >> Also, I have seen high speed bad behaved devices not responding to > >> > >> PING tokens in status phase of control transfers. Are you > >> > >also getting > >> > >> this issue ? > >> > > > >> > >yes, we had PING problems, and we've posted other patches in > >> > >the past for that, but this seems to be the most correct > >> > >version so far. > >> > > > >> > >search for like blackfin+ping+musb on some lists if you're > >> > >interested in the history. > >> > >-mike > >> > > > >> -- > >> 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 > > -- > > 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 > > -- 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
