From: linux-usb-owner@xxxxxxxxxxxxxxx [mailto:linux-usb-owner@xxxxxxxxxxxxxxx] On Behalf Of Felipe Balbi Sent: Thursday, September 25, 2014 7:51 AM > On Thu, Sep 25, 2014 at 03:21:46PM +0800, Huang Rui wrote: > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > > index 0fcc0a3..8277065 100644 > > --- a/drivers/usb/dwc3/gadget.c > > +++ b/drivers/usb/dwc3/gadget.c > > @@ -2635,6 +2635,7 @@ static irqreturn_t dwc3_interrupt(int irq, void *_dwc) > > */ > > int dwc3_gadget_init(struct dwc3 *dwc) > > { > > + u32 reg; > > int ret; > > > > dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req), > > @@ -2689,6 +2690,13 @@ int dwc3_gadget_init(struct dwc3 *dwc) > > if (ret) > > goto err4; > > > > + if (dwc->quirks & DWC3_AMD_NL_PLAT) { > > + reg = dwc3_readl(dwc->regs, DWC3_DCTL); > > + reg |= DWC3_DCTL_LPM_ERRATA(0xf); > > weird, why would Synopsys put this here ? It seems like this is only > useful when LPM Errata is enabled and that's, apparently, a host-side > thing. > > Paul, can you comment ? These bits contribute to how the device responds to an LPM transaction from the host. If DCFG.LPMCap=1, they set the BESL value above which the core will send a NYET. If DCFG.LPMCap=0, they have no effect. So it's definitely a device-side thing, but only if the core is configured with LPM Errata support enabled. -- Paul -- 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
