Re: [PATCH] dma-mapping: move dma configuration to bus infrastructure

From: hch@xxxxxx
Date: Tue Mar 13 2018 - 03:27:36 EST


On Tue, Mar 13, 2018 at 04:22:53AM +0000, Nipun Gupta wrote:
> > Isn't this one or the other one but not both?
> >
> > Something like:
> >
> > if (dev->of_node)
> > of_dma_deconfigure(dev);
> > else
> > acpi_dma_deconfigure(dev);
> >
> > should work.
>
> I understand your point. Seems reasonable as we should not expect
> the 'of/acpi DMA deconfigure' API to not fail when they are not configured.
>
> But, here we would also need to get dma_device (just as we get in
> 'pci_dma_configure') and need a check on it as for PCI there 'of_node'
> is present in the dma_dev.

Both of_dma_deconfigure and acpi_dma_deconfigure just end up calling
arch_teardown_dma_ops. So my preference would be to just remove
of_dma_deconfigure and acpi_dma_deconfigure and call arch_teardown_dma_ops
as a prep patch before this one.