[PATCH 1/9 v2] ARM: at91: usb ohci add dt support

Jean-Christophe PLAGNIOL-VILLARD plagnioj at jcrosoft.com
Wed Mar 7 11:45:13 EST 2012


On 11:33 Wed 07 Mar     , Jean-Christophe PLAGNIOL-VILLARD wrote:
> On 09:34 Wed 07 Mar     , Russell King - ARM Linux wrote:
> > On Wed, Mar 07, 2012 at 10:15:38AM +0100, Jean-Christophe PLAGNIOL-VILLARD wrote:
> > > +static u64 at91_ohci_dma_mask = DMA_BIT_MASK(32);
> > > +
> > > +static int __devinit ohci_at91_of_init(struct platform_device *pdev)
> > > +{
> > > +	struct device_node *np = pdev->dev.of_node;
> > > +	int i, ret, gpio;
> > > +	enum of_gpio_flags flags;
> > > +	struct at91_usbh_data	*pdata;
> > > +	u32 ports;
> > > +
> > > +	if (!np)
> > > +		return 0;
> > > +
> > > +	/* Right now device-tree probed devices don't get dma_mask set.
> > > +	 * Since shared usb code relies on it, set it here for now.
> > > +	 * Once we have dma capability bindings this can go away.
> > > +	 */
> > > +	if (!pdev->dev.dma_mask)
> > > +		pdev->dev.dma_mask = &at91_ohci_dma_mask;
> > 
> > That sounds like a rather big omission from DT - what's happening to
> > address this (before we end up with lots of drivers with this).  Pretty
> > much any device which does DMA needs both this and the coherent DMA mask
> > set properly.
> > 
> > We really don't want this kind of workaround scattered in every driver
> > which has been converted to DT.
> Tegra do it also
> I do yet found a good generic way in DT
> 
> Today only usb need I do plan to drop it for 3.5 can we have for 3.4
I send a patch to propose a binding for both dma-mask and coherent dma mask

If it does not got for 3.4 can this temporary fix up go?

Best Regards,
J.



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