[RESEND][PATCH v2] dmaengine: bcm2835: Add slave dma support

Vinod Koul vinod.koul at intel.com
Thu Dec 17 22:05:26 PST 2015


On Thu, Dec 17, 2015 at 07:11:48PM +0100, Martin Sperl wrote:

> +
> +			/* Setup addresses */
> +			if (d->dir == DMA_DEV_TO_MEM) {
> +				control_block->info = BCM2835_DMA_D_INC |
> +						      BCM2835_DMA_D_WIDTH |
> +						      BCM2835_DMA_S_DREQ;
> +				control_block->src = dev_addr;
> +				control_block->dst = addr + (dma_addr_t)j;
> +			} else {
> +				control_block->info = BCM2835_DMA_S_INC |
> +						      BCM2835_DMA_S_WIDTH |
> +						      BCM2835_DMA_D_DREQ;
> +				control_block->src = addr + (dma_addr_t)j;
> +				control_block->dst = dev_addr;
> +			}
> +
> +			/* Common part */
> +			control_block->info |=
> +				BCM2835_DMA_WAITS(BCM2835_DMA_WAIT_CYCLES);
> +			control_block->info |= BCM2835_DMA_WAIT_RESP;
> +
> +			/* Enable */
> +			if (i == sg_len - 1 && len - j <= max_size)
> +				control_block->info |= BCM2835_DMA_INT_EN;
> +
> +			/* Setup synchronization */
> +			if (sync_type)
> +				control_block->info |= sync_type;
> +
> +			/* Setup DREQ channel */
> +			if (c->dreq)
> +				control_block->info |=
> +					BCM2835_DMA_PER_MAP(c->dreq);
> +
> +			/* Length of a frame */
> +			control_block->length = min(len - j, max_size);
> +			d->size += control_block->length;
> +
> +			if (i < sg_len - 1 || len - j > max_size) {
> +				/* Next block is the next frame. */
> +				control_block->next =
> +					d->control_block_base_phys +
> +					sizeof(struct bcm2835_dma_cb) *
> +					(i + split_cnt + 1);
> +			} else {
> +				/* Next block is empty. */
> +				control_block->next = 0;
> +			}
> +
> +			if (len - j > max_size)
> +				split_cnt++;

Most of this part is common with the cyclic and seems copy paste. Can we
use common routine to do common work please

-- 
~Vinod



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