ASoC: SOF: Intel: Read the LLP via the associated Link DMA channel #5539
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ranj063
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Sep 18, 2025
| { | ||
| struct hdac_stream *hstream = substream->runtime->private_data; | ||
| struct hdac_ext_stream *hext_stream = stream_to_hdac_ext_stream(hstream); | ||
| struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream); |
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@ujfalusi this makes perfect sense. You just have a minor typo in the commit message, otherwise good to go: "fro"
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It is allowed to mix Link and Host DMA channels in a way that their index is different. In this case we would read the LLP from a channel which is not used or used for other operation. Such case can be reproduced on cAVS2.5 or ACE1 platforms with soundwire configuration: playback to SDW would take Host channel 0 (stream_tag 1) and no Link DMA used Second playback to HDMI (HDA) would use Host channel 1 (stream_tag 2) and Link channel 0 (stream_tag 1). In this case reading the LLP from channel 2 is incorrect as that is not the Link channel used for the HDMI playback. To correct this, we should look up the BE and get the channel used on the Link side. Fixes: 67b182b ("ASoC: SOF: Intel: hda: Implement get_stream_position (Linear Link Position)") Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
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kv2019i
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Sep 19, 2025
ranj063
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Sep 19, 2025
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It is allowed to mix Link and Host DMA channels in a way that their index is different. In this case we would read the LLP from a channel which is not used or used for other operation.
Such case can be reproduced on cAVS2.5 or ACE1 platforms with soundwire configuration:
playback to SDW would take Host channel 0 (stream_tag 1) and no Link DMA used
Second playback to HDMI (HDA) would use Host channel 1 (stream_tag 2) and Link channel 0 (stream_tag 1).
In this case reading the LLP from channel 2 is incorrect as that is not the Link channel used fro the HDMI playback.
To correct this, we should look up the BE and get the channel used on the Link side.
Fixes: 67b182b ("ASoC: SOF: Intel: hda: Implement get_stream_position (Linear Link Position)")