Hi, On Wed, Aug 05, 2015 at 12:05:02AM +0200, Hans de Goede wrote: > Hi, > > On 08/04/2015 11:35 PM, Felipe Balbi wrote: > >On Tue, Aug 04, 2015 at 11:25:53PM +0200, Hans de Goede wrote: > >>For some unclear reason sometimes we get VBus errors in host-only mode, > >>even though we do not have any vbus-detection then. Ignore these. > >> > >>Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> > >>--- > >> drivers/usb/musb/sunxi.c | 4 ++++ > >> 1 file changed, 4 insertions(+) > >> > >>diff --git a/drivers/usb/musb/sunxi.c b/drivers/usb/musb/sunxi.c > >>index f9f6304..34ce5df 100644 > >>--- a/drivers/usb/musb/sunxi.c > >>+++ b/drivers/usb/musb/sunxi.c > >>@@ -194,6 +194,10 @@ static irqreturn_t sunxi_musb_interrupt(int irq, void *__hci) > >> musb_writeb(musb->mregs, MUSB_FADDR, 0); > >> } > >> > >>+ /* Ignore Vbus errors when in host only mode */ > >>+ if (musb->port_mode == MUSB_PORT_MODE_HOST) > >>+ musb->int_usb &= ~MUSB_INTR_VBUSERROR; > > > >check with a scope if VBUS is really dropping. Host does VBUS detection > >indeed, at a minimum, for overcurrent protection. You might have > >something causing VBUS to drop and that something needs to be found, > >rather than masked. > > The boards in question do not have any vbus detection, the usb-phy on > allwinner boards do not have a vbus sense pin, instead a gpio is used > in designs which use otg. Designs which use host-only mode typically > do not have any form of vbus detection at all. In this case we always > report vbus as being valid to the musb core, so I've no idea why > the musb core is still generating vbus errors. PHY must tell MUSB about VBUS level using either ULPI or UTMI+. I'd check to see if the PHY is at fault, at least. -- balbi
Attachment:
signature.asc
Description: Digital signature
