On Thu, 15 May 2014, Mark Brown wrote: > On Thu, May 15, 2014 at 04:17:44PM +0100, Liviu Dudau wrote: > > On Thu, May 15, 2014 at 03:11:48PM +0100, Alan Stern wrote: > > > On Wed, 14 May 2014, Mark Brown wrote: > > > > Did you folks tested this for all sorts of host controllers? I have no > > > way to verify that it works, and last I heard, many (or even most) > > > controllers don't work right with 64-bit DMA. > > > I have tested it with a host controller that is capable of 64-bit DMA and > > without this change it doesn't work. At the moment it is the only known > > USB host controller enabled for arm64. And 64-bit DMA works fine on arm64. > > We should probably conditionalise the device configuration on > dma_set_mask() succeeding - any device that can't handle 64 bit DMA > should be set up to constrain things appropriately. Last I heard, there were EHCI controllers that claimed to handle 64-bit DMA but got it wrong. I don't know to what extent this may still be true. Alan Stern -- 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
