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On ACE2+ platforms the link DMA stream allocator must avoid two hardware errata in mlink-capable systems: - Concurrent (cross-direction) hazard: when SoundWire shares a physical link DMA stream index with HDaudio, iDisp or UAOL across the two directions, the LLP and timestamp values for the affected stream are wrong. SSP and DMIC are not affected because every DMA request from those links carries one sample block. - Sequential (playback only) hazard: once a HDaudio or iDisp link has used a playback stream index, that index cannot drive any non HDA/iDisp link in the same direction until the next controller reset (CRST#). Track the active link type per direction in two masks (one for SoundWire, one for HDA/iDisp/UAOL) and the persistent set of playback stream indices touched by HDA/iDisp in a third mask. The link DMA allocator skips streams that would violate either rule. Streams are released from the active masks when the stream is released; all masks are cleared in hda_dsp_ctrl_init_chip() because the CRST# performed there clears the hardware state as well. A new helper hda_bus_ml_link_get_type() returns the link type from the existing extended link descriptor so the SOF allocator can tell SoundWire, HDA/iDisp and UAOL apart without duplicating the parsing. The implementation is generic. On platforms older than ACE2 every link is reported as HDA, only the sequential mask is ever set and it has no effect because no other link types are present, so behavior is unchanged. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com> Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com> Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com> Link: https://patch.msgid.link/20260730125130.29887-5-peter.ujfalusi@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>