Re: [RFC v02 00/15] dmaengine: New 'universal' API for requesting channel

Arnd Bergmann
2015-12-01T14:25:15Z

On Tuesday 01 December 2015 15:45:32 Peter Ujfalusi wrote:
> >> static struct dma_filter_map da830_edma_map[] = {
> >> DMA_FILTER_ENTRY("davinci-mcasp.0", "rx", EDMA_CTLR_CHAN(0, 0)),
> >> DMA_FILTER_ENTRY("davinci-mcasp.0", "tx", EDMA_CTLR_CHAN(0, 1)),
> >> DMA_FILTER_ENTRY("davinci-mcasp.1", "rx", EDMA_CTLR_CHAN(0, 2)),
> >> DMA_FILTER_ENTRY("davinci-mcasp.1", "tx", EDMA_CTLR_CHAN(0, 3)),
> >> DMA_FILTER_ENTRY("davinci-mcasp.2", "rx", EDMA_CTLR_CHAN(0, 4)),
> >> DMA_FILTER_ENTRY("davinci-mcasp.2", "tx", EDMA_CTLR_CHAN(0, 5)),
> >> DMA_FILTER_ENTRY("spi_davinci.0", "rx", EDMA_CTLR_CHAN(0, 14)),
> >> DMA_FILTER_ENTRY("spi_davinci.0", "tx", EDMA_CTLR_CHAN(0, 15)),
> >> DMA_FILTER_ENTRY("da830-mmc.0", "rx", EDMA_CTLR_CHAN(0, 16)),
> >> DMA_FILTER_ENTRY("da830-mmc.0", "tx", EDMA_CTLR_CHAN(0, 17)),
> >> DMA_FILTER_ENTRY("spi_davinci.1", "rx", EDMA_CTLR_CHAN(0, 18)),
> >> DMA_FILTER_ENTRY("spi_davinci.1", "tx", EDMA_CTLR_CHAN(0, 19)),
> >
> > Does this ".2" and so prevent driver to use auto ID for platform devices?
>
> Yes, as all the infra around the traditional board files with platform_device
> creation does. Ideally we could have 'phandle' pointing from this table to the
> device in question (or other way around), but I'm not aware of anything we can
> use.

I was thinking that we could use a pointer to the device structure, but
if you have that, you can also just read the name from it.

Arnd