Commit 087809fc authored Jan 21, 2011 by Jamie Iles Committed by Dan Williams Jan 29, 2011

dmaengine/dw_dmac: don't scan descriptors if no xfers in progress



Some hardware (picoChip picoXCell in particular) sometimes has
the block transfer complete bit being set for a channel after the
whole transfer has completed. If we don't have any transfers in the
active list then don't bother to scan the descriptors. This often
happens in normal operation and doesn't require the channel to be
reset.

v2: cleanup whitespace

Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

parent e8a7e48b

drivers/dma/dw_dmac.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -291,6 +291,9 @@ static void dwc_scan_descriptors(struct dw_dma dw, struct dw_dma_chan dwc)
		return;
		}

		if (list_empty(&dwc->active_list))
		return;

		dev_vdbg(chan2dev(&dwc->chan), "scan_descriptors: llp=0x%x\n", llp);

		list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {

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