Re: [PATCH 1/4] usb: dwc3: dwc3-omap: set dma_mask for dwc3 inorderfor host mode to work

[kishon]

Hi,

On Tuesday 05 March 2013 08:24 PM, Felipe Balbi wrote:
> On Tue, Mar 05, 2013 at 07:51:57PM +0530, Kishon Vijay Abraham I wrote:
> > While creating the child devices, *of_platform_populate* sets only
> > coherent_dma_mask but USBHCD sets *uses_dma* (determines whether the
> > controller is DMA'able) based on dma_mask. So If we haven't explicitly set
> > dma_mask, the HCD thinks the controller is not DMA'able and the
> > controller will fail. So explicity set dma_mask for dwc3 after
> > *of_platform_populate*.
> >
> > Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> > ---
> >   drivers/usb/dwc3/dwc3-omap.c |   10 ++++++++++
> >   1 file changed, 10 insertions(+)
> >
> > diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
> > index 35b9673..19c6e72 100644
> > --- a/drivers/usb/dwc3/dwc3-omap.c
> > +++ b/drivers/usb/dwc3/dwc3-omap.c
> > @@ -277,6 +277,14 @@ static void dwc3_omap_disable_irqs(struct dwc3_omap *omap)
> >   	dwc3_omap_writel(omap->base, USBOTGSS_IRQENABLE_SET_0, 0x00);
> >   }
> >
> > +static u64 dwc3_omap_dma_mask = DMA_BIT_MASK(32);
> > +
> > +static int dwc3_omap_set_dmamask(struct device *dev, void *c)
> > +{
> > +	dev->dma_mask = &dwc3_omap_dma_mask;
> > +	return 0;
> > +}
> > +
> >   static int dwc3_omap_probe(struct platform_device *pdev)
> >   {
> >   	struct device_node	*node = pdev->dev.of_node;
> > @@ -381,6 +389,8 @@ static int dwc3_omap_probe(struct platform_device *pdev)
> >   		return ret;
> >   	}
> >
> > +	device_for_each_child(&pdev->dev, NULL, dwc3_omap_set_dmamask);
>
> I don't think this is correct. Child should be setting its own by
> copying from parent. In summary I think we should add this to dwc3 core:
>
> dma_set_coherent_mask(&pdev->dev, pdev->dev.parent->coherent_dma_mask);
> pdev->dev.dma_mask = pdev->dev.parent->dma_mask;
> pdev->dev.dma_parms = pdev->dev.parent->dma_parms;
>
> And add the same thing to xhci-plat.c btw.

hmm.. ok.

Thanks
Kishon
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