This is a note to let you know that I've just added the patch titled dmaengine: Fix choppy sound because of unimplemented resume to the 4.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dmaengine-fix-choppy-sound-because-of-unimplemented-resume.patch and it can be found in the queue-4.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 88d04643c66052a1cf92a6fd5f92dff0f7757f61 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> Date: Wed, 10 Jun 2015 17:17:07 +0900 Subject: dmaengine: Fix choppy sound because of unimplemented resume From: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> commit 88d04643c66052a1cf92a6fd5f92dff0f7757f61 upstream. Some drivers implement only pause operation (no resuming). Example is pl330 where pause is needed for getting residuum. pl330 does not support resume operation, transfer must be stopped after pause. However for slaves this is exposed always as "pause and resume" which introduces subtle errors on Odroid U3 board (Exynos4412 with pl330). After adding pause function to pl330 driver the audio playback (utilizing DMA) gets choppy after some time (approximately 24 hours). Fix this by exposing "cmd_pause" if and only if pause and resume are implemented. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> Reported-by: gabriel@xxxxxxxxx Reported-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Fixes: 88987d2c7534 ("dmaengine: pl330: add DMA_PAUSE feature") Acked-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/dma/dmaengine.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -505,7 +505,11 @@ int dma_get_slave_caps(struct dma_chan * caps->directions = device->directions; caps->residue_granularity = device->residue_granularity; - caps->cmd_pause = !!device->device_pause; + /* + * Some devices implement only pause (e.g. to get residuum) but no + * resume. However cmd_pause is advertised as pause AND resume. + */ + caps->cmd_pause = !!(device->device_pause && device->device_resume); caps->cmd_terminate = !!device->device_terminate_all; return 0; Patches currently in stable-queue which might be from k.kozlowski@xxxxxxxxxxx are queue-4.0/dmaengine-fix-choppy-sound-because-of-unimplemented-resume.patch queue-4.0/dmaengine-pl330-fix-hang-on-dmaengine_terminate_all-on-certain-boards.patch queue-4.0/i2c-s3c2410-fix-oops-in-suspend-callback-for-non-dt.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in