Commit 5a6187d7 authored Aug 29, 2018 by Daniel Silsby Committed by Vinod Koul Sep 11, 2018

dmaengine: dma-jz4780: Add missing residue DTC mask



The 'dtc' word in jz DMA descriptors contains two fields: The
lowest 24 bits are the transfer count, and upper 8 bits are the DOA
offset to next descriptor. The upper 8 bits are now correctly masked
off when computing residue in jz4780_dma_desc_residue(). Note that
reads of the DTCn hardware reg are automatically masked this way.

Signed-off-by: Daniel Silsby <dansilsby@gmail.com>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

parent 17a8e30e

drivers/dma/dma-jz4780.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -616,7 +616,8 @@ static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan,
		residue = 0;

		for (i = next_sg; i < desc->count; i++)
		residue += desc->desc[i].dtc << jzchan->transfer_shift;
		residue += (desc->desc[i].dtc & GENMASK(23, 0)) <<
		jzchan->transfer_shift;

		if (next_sg != 0) {
		count = jz4780_dma_chn_readl(jzdma, jzchan->id,

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