The patch
ASoC: Intel: Skylake: Use DPIB to update position for Playback stream
has been applied to the asoc tree at
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying to this mail.
Thanks, Mark
From 9a58725ba533b46db31d10a6dcc5ab7f9fa370ed Mon Sep 17 00:00:00 2001
From: Dharageswari R dharageswari.r@intel.com Date: Thu, 6 Oct 2016 08:51:21 +0530 Subject: [PATCH] ASoC: Intel: Skylake: Use DPIB to update position for Playback stream
DPIB is read currently from a buffer position in memory (indicated by the registers DPIB[U|L]BASE).Driver reads the position buffer on BDL completion interrupts to report the DMA position. But the BDL completion interrupt only indicates the last DMA transfer of the buffer is completed at the Intel HD Audio subsystem boundary. The periodic DMA Position-in-Buffer writes may be scheduled at the same time or later than the MSI and does not guarantee to reflect the position of the last buffer that was transferred.
Whereas DPIB register in HDA space(vendor specific register indicated by SDxDPIB) reflects the actual data that is transferred. Hence update the position based on DPIB for playback.
Signed-off-by: Dharageswari R dharageswari.r@intel.com Signed-off-by: Jeeja KP jeeja.kp@intel.com Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/intel/skylake/skl-pcm.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-)
diff --git a/sound/soc/intel/skylake/skl-pcm.c b/sound/soc/intel/skylake/skl-pcm.c index 58c728662600..c966b40da180 100644 --- a/sound/soc/intel/skylake/skl-pcm.c +++ b/sound/soc/intel/skylake/skl-pcm.c @@ -1031,10 +1031,24 @@ static snd_pcm_uframes_t skl_platform_pcm_pointer (struct snd_pcm_substream *substream) { struct hdac_ext_stream *hstream = get_hdac_ext_stream(substream); + struct hdac_ext_bus *ebus = get_bus_ctx(substream); unsigned int pos;
- /* use the position buffer as default */ - pos = snd_hdac_stream_get_pos_posbuf(hdac_stream(hstream)); + /* + * Use DPIB for Playback stream as the periodic DMA Position-in- + * Buffer Writes may be scheduled at the same time or later than + * the MSI and does not guarantee to reflect the Position of the + * last buffer that was transferred. Whereas DPIB register in + * HAD space reflects the actual data that is transferred. + * Use the position buffer for capture, as DPIB write gets + * completed earlier than the actual data written to the DDR. + */ + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + pos = readl(ebus->bus.remap_addr + AZX_REG_VS_SDXDPIB_XBASE + + (AZX_REG_VS_SDXDPIB_XINTERVAL * + hdac_stream(hstream)->index)); + else + pos = snd_hdac_stream_get_pos_posbuf(hdac_stream(hstream));
if (pos >= hdac_stream(hstream)->bufsize) pos = 0;