Hi Russell, ---- On Wed, 28 Jun 2023 19:02:47 +0800 Russell King (Oracle) wrote --- > On Wed, Jun 28, 2023 at 06:57:35PM +0800, Li Chen wrote: > > Hi all, > > > > I recently encountered an issue where the dma_mask was set in the DMA controller's driver, but the consumer peripheral driver didn't set its own dma_mask. > > It should always take the device that is *actually* performing the DMA, > since that is the device that has restrictions on what addresses can be > accessed, etc. > > Devices that "consume" the data from a DMA controller don't access > memory - they are merely the targets, and they can't on their own access > host memory. Therefore, their dma mask _should_ be irrelevant. Thanks for your quick response. Therefore, I just need to use chan->device->dev in my dma_map_single and there is no need to configure the dma_mask for my consumer peripherals. Regards, Li
