On Tue, 1 Sep 2020 at 17:40, Christoph Hellwig <hch@xxxxxx> wrote: > > On Tue, Sep 01, 2020 at 05:36:17PM +0200, Ulf Hansson wrote: > > > I still don't think this makes sense, as the dma_mask should always > > > be non-NULL here. > > > > If that is the case, I wonder how the driver could even have worked without DMA. > > > > Because in the existing code, host->dma_dev gets assigned to > > spi->master->dev.parent->dma_mask - which seems to turn on the DMA > > usage in the driver. > > > > What am I missing? > > Do you know of other non-DMA users? For SH nommu it probably worked I don't know of other non-DMA users. As I said, I wish someone could step in and take better care of mmc_spi - as I know it's being used a lot. > because SH nommu used to provide a DMA implementation that worked > fine for streaming maps, but was completely broken for coherent > allocation. And this driver appears to only use the former. Alright, so you are saying the DMA support may potentially never have been optional to this driver. In any case, I can remove the check in $subject patch, as it shouldn't matter. Anyway, let's see what Rich thinks of this. I am curious to see if the patch works on his SH boards - as I haven't been able to test it. Kind regards Uffe
