ASoC: SOF: Intel: hda-dai: reset dma_data and release stream

The sequences are missing a call to snd_soc_dai_set_dma_data() when
the stream is cleared, as well as a release of the stream, and tests
to avoid pointer dereferences.

This fixes an underflow issue in a corner case with two streams paused
before a suspend-resume cycle. After resume, the pause_release of the
last stream causes an underflow due to an invalid sequence.

This problem probably existed since the beginning and is only see with
prototypes of a 'deep-buffer' capability, which depends on additional
ASoC fixes, so there's is no Fixes: tag and no real requirement to
backport this patch.

BugLink: https://github.com/thesofproject/linux/issues/3151
Co-developed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220421203201.1550328-13-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/sof/intel/hda-dai.c b/sound/soc/sof/intel/hda-dai.c
index dbccd75..644f750 100644 (file)
--- a/sound/soc/sof/intel/hda-dai.c
+++ b/sound/soc/sof/intel/hda-dai.c
@@ -230,6 +230,9 @@ static int hda_link_dma_trigger(struct snd_pcm_substream *substream, int cmd)
                return -EINVAL;
 
        dev_dbg(cpu_dai->dev, "%s: cmd=%d\n", __func__, cmd);
+       if (!hext_stream)
+               return 0;
+
        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
@@ -243,8 +246,10 @@ static int hda_link_dma_trigger(struct snd_pcm_substream *substream, int cmd)
                        stream_tag = hdac_stream(hext_stream)->stream_tag;
                        snd_hdac_ext_link_clear_stream_id(link, stream_tag);
                }
-
+               snd_soc_dai_set_dma_data(cpu_dai, substream, NULL);
+               snd_hdac_ext_stream_release(hext_stream, HDAC_EXT_STREAM_TYPE_LINK);
                hext_stream->link_prepared = 0;
+
                break;
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                snd_hdac_ext_link_stream_clear(hext_stream);
@@ -370,7 +375,7 @@ static int ipc3_hda_dai_prepare(struct snd_pcm_substream *substream,
        int stream = substream->stream;
        int ret;
 
-       if (hext_stream->link_prepared)
+       if (hext_stream && hext_stream->link_prepared)
                return 0;
 
        dev_dbg(sdev->dev, "%s: prepare stream dir %d\n", __func__, substream->stream);
@@ -460,6 +465,8 @@ static int hda_dai_suspend(struct hdac_bus *bus)
 
        /* set internal flag for BE */
        list_for_each_entry(s, &bus->stream_list, list) {
+               struct sof_intel_hda_stream *hda_stream;
+
                hext_stream = stream_to_hdac_ext_stream(s);
 
                /*
@@ -489,13 +496,20 @@ static int hda_dai_suspend(struct hdac_bus *bus)
                                stream_tag = hdac_stream(hext_stream)->stream_tag;
                                snd_hdac_ext_link_clear_stream_id(link, stream_tag);
                        }
+                       snd_soc_dai_set_dma_data(cpu_dai, hext_stream->link_substream, NULL);
+                       snd_hdac_ext_stream_release(hext_stream, HDAC_EXT_STREAM_TYPE_LINK);
                        hext_stream->link_prepared = 0;
 
+                       /* free the host DMA channel reserved by hostless streams */
+                       hda_stream = hstream_to_sof_hda_stream(hext_stream);
+                       hda_stream->host_reserved = 0;
+
                        /* for consistency with TRIGGER_SUSPEND we free DAI resources */
                        ret = hda_dai_hw_free_ipc(hdac_stream(hext_stream)->direction, cpu_dai);
                        if (ret < 0)
                                return ret;
                }
+
        }
 
        return 0;