On Thursday 17 July 2014 19:19:15 Peter Chen wrote: > > Currently, we are designing a generic driver, we don't know what's the > hardware architecture, we are trying to find a solution how to set > dma mask for all possible devices which will use this driver, Antoine's > this patch is trying to cover this feature. > > For example, > > Marvell Berlin doesn't need to set dma mask specific. > http://marc.info/?l=linux-arm-kernel&m=140205228507045&w=2 > http://www.spinics.net/lists/linux-usb/msg110598.html > > Xilinx zynq needs to set dma mask as 0xFFFFFFF0 > http://marc.info/?l=linux-usb&m=140384129921706&w=2 > > FSL i.mx needs to set dma mask as DMA_BIT_MASK(32) > https://git.kernel.org/cgit/linux/kernel/git/gregkh/usb.git/tree/drivers/usb/chipidea/ci_hdrc_imx.c?h=usb-next Ok, I see now. I think we can safely drop it completely then: - Berlin was only recently added and doesn't need to set the mask because the common code handles it just fine now. - i.mx was added earlier, at a time where it was still necessary - zynq just made a mistake, 0xFFFFFFF0 was never a valid mask and just happened to work by accident. In summary, the 32-bit default mask will work on all of them, and we need no special code or DT properties for it. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
