From 3f261e5838c9c5def6aae5f2a08a82ec8b4150b0 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Fri, 13 Aug 2021 13:33:57 -0500 Subject: [PATCH 1/9] ASoC: soc-pcm: protect BE dailink state changes in trigger When more than one FE is connected to a BE, e.g. in a mixing use case, the BE can be triggered multiple times when the FE are opened/started concurrently. This race condition is problematic in the case of SoundWire BE dailinks, and this is not desirable in a general case. The code carefully checks when the BE can be stopped or hw_free'ed, but the trigger code does not use any mutual exclusion. Fix by using the same spinlock already used to check FE states, and set the state before the trigger. In case of errors, the initial state will be restored. This patch does not change how the triggers are handled, it only makes sure the states are handled in critical sections. Signed-off-by: Pierre-Louis Bossart --- sound/soc/soc-pcm.c | 103 ++++++++++++++++++++++++++++++++++++-------- 1 file changed, 85 insertions(+), 18 deletions(-) diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index fc1854e3e43fd8..86c13b784a403a 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -1998,6 +1998,8 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, { struct snd_soc_pcm_runtime *be; struct snd_soc_dpcm *dpcm; + enum snd_soc_dpcm_state state; + unsigned long flags; int ret = 0; for_each_dpcm_be(fe, stream, dpcm) { @@ -2015,76 +2017,141 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, switch (cmd) { case SNDRV_PCM_TRIGGER_START: + spin_lock_irqsave(&fe->card->dpcm_lock, flags); if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_PREPARE) && (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) && - (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED)) + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED)) { + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; + } + state = be->dpcm[stream].state; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); ret = soc_pcm_trigger(be_substream, cmd); - if (ret) + if (ret) { + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + be->dpcm[stream].state = state; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; + } - be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; break; case SNDRV_PCM_TRIGGER_RESUME: - if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND)) + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND) { + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; + } + + state = be->dpcm[stream].state; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); ret = soc_pcm_trigger(be_substream, cmd); - if (ret) + if (ret) { + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + be->dpcm[stream].state = state; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; + } - be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; break; case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: - if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED)) + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED) { + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; + } + + state = be->dpcm[stream].state; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); ret = soc_pcm_trigger(be_substream, cmd); - if (ret) + if (ret) { + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + be->dpcm[stream].state = state; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; + } - be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; break; case SNDRV_PCM_TRIGGER_STOP: + spin_lock_irqsave(&fe->card->dpcm_lock, flags); if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_START) && - (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED)) + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED)) { + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; + } + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream)) continue; + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + state = be->dpcm[stream].state; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_STOP; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); + ret = soc_pcm_trigger(be_substream, cmd); - if (ret) + if (ret) { + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + be->dpcm[stream].state = state; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; + } - be->dpcm[stream].state = SND_SOC_DPCM_STATE_STOP; break; case SNDRV_PCM_TRIGGER_SUSPEND: - if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START) + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START) { + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; + } + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream)) continue; + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + state = be->dpcm[stream].state; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_STOP; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); + ret = soc_pcm_trigger(be_substream, cmd); - if (ret) + if (ret) { + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + be->dpcm[stream].state = state; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; + } - be->dpcm[stream].state = SND_SOC_DPCM_STATE_SUSPEND; break; case SNDRV_PCM_TRIGGER_PAUSE_PUSH: - if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START) + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START) { + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; + } + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream)) continue; + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + state = be->dpcm[stream].state; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_PAUSED; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); + ret = soc_pcm_trigger(be_substream, cmd); - if (ret) + if (ret) { + spin_lock_irqsave(&fe->card->dpcm_lock, flags); + be->dpcm[stream].state = state; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; + } - be->dpcm[stream].state = SND_SOC_DPCM_STATE_PAUSED; break; } } From d1ed4e693b20ab45086471d73eb3e65dee5d45d0 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 16 Aug 2021 16:40:18 -0500 Subject: [PATCH 2/9] ASoC: soc-pcm: test refcount before triggering On start/pause_release/resume, when more than one FE is connected to the same BE, it's possible that the trigger is sent more than once. This is not desirable, we only want to trigger a BE once, which is straightforward to implement with a refcount. For stop/pause/suspend, the problem is more complicated: the check implemented in snd_soc_dpcm_can_be_free_stop() may fail due to a conceptual deadlock when we trigger the BE before the FE. In this case, the FE states have not yet changed, so there are corner cases where the TRIGGER_STOP is never sent - the dual case of start where multiple triggers might be sent. This patch suggests an unconditional trigger in all cases, without checking the FE states, using a refcount protected by a spinlock. Signed-off-by: Pierre-Louis Bossart --- include/sound/soc-dpcm.h | 2 ++ sound/soc/soc-pcm.c | 56 ++++++++++++++++++++++++++++++++++++---- 2 files changed, 53 insertions(+), 5 deletions(-) diff --git a/include/sound/soc-dpcm.h b/include/sound/soc-dpcm.h index bc7af90099a8d5..2fec5d91f0d091 100644 --- a/include/sound/soc-dpcm.h +++ b/include/sound/soc-dpcm.h @@ -101,6 +101,8 @@ struct snd_soc_dpcm_runtime { enum snd_soc_dpcm_state state; int trigger_pending; /* trigger cmd + 1 if pending, 0 if not */ + + int be_start; /* refcount protected by dpcm_lock */ }; #define for_each_dpcm_fe(be, stream, _dpcm) \ diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 86c13b784a403a..616489d985475f 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -1534,7 +1534,7 @@ int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream) be->dpcm[stream].state = SND_SOC_DPCM_STATE_CLOSE; goto unwind; } - + be->dpcm[stream].be_start = 0; be->dpcm[stream].state = SND_SOC_DPCM_STATE_OPEN; count++; } @@ -2000,6 +2000,7 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, struct snd_soc_dpcm *dpcm; enum snd_soc_dpcm_state state; unsigned long flags; + bool do_trigger; int ret = 0; for_each_dpcm_be(fe, stream, dpcm) { @@ -2015,23 +2016,33 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, dev_dbg(be->dev, "ASoC: trigger BE %s cmd %d\n", be->dai_link->name, cmd); + do_trigger = false; switch (cmd) { case SNDRV_PCM_TRIGGER_START: spin_lock_irqsave(&fe->card->dpcm_lock, flags); - if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_PREPARE) && + if (!be->dpcm[stream].be_start && + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PREPARE) && (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) && (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED)) { spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; } state = be->dpcm[stream].state; + be->dpcm[stream].be_start++; + if (be->dpcm[stream].be_start == 1) + do_trigger = true; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); + if (!do_trigger) + continue; + ret = soc_pcm_trigger(be_substream, cmd); if (ret) { spin_lock_irqsave(&fe->card->dpcm_lock, flags); be->dpcm[stream].state = state; + be->dpcm[stream].be_start--; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; } @@ -2045,13 +2056,21 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, } state = be->dpcm[stream].state; + be->dpcm[stream].be_start++; + if (be->dpcm[stream].be_start == 1) + do_trigger = true; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); + if (!do_trigger) + continue; + ret = soc_pcm_trigger(be_substream, cmd); if (ret) { spin_lock_irqsave(&fe->card->dpcm_lock, flags); be->dpcm[stream].state = state; + be->dpcm[stream].be_start--; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; } @@ -2065,13 +2084,21 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, } state = be->dpcm[stream].state; + be->dpcm[stream].be_start++; + if (be->dpcm[stream].be_start == 1) + do_trigger = true; + be->dpcm[stream].state = SND_SOC_DPCM_STATE_START; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); + if (!do_trigger) + continue; + ret = soc_pcm_trigger(be_substream, cmd); if (ret) { spin_lock_irqsave(&fe->card->dpcm_lock, flags); be->dpcm[stream].state = state; + be->dpcm[stream].be_start--; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; } @@ -2084,9 +2111,15 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; } + if (be->dpcm[stream].state == SND_SOC_DPCM_STATE_START) + be->dpcm[stream].be_start--; + + if (be->dpcm[stream].be_start == 0) + do_trigger = true; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); - if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream)) + if (!do_trigger) continue; spin_lock_irqsave(&fe->card->dpcm_lock, flags); @@ -2098,6 +2131,8 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, if (ret) { spin_lock_irqsave(&fe->card->dpcm_lock, flags); be->dpcm[stream].state = state; + if (be->dpcm[stream].state == SND_SOC_DPCM_STATE_START) + be->dpcm[stream].be_start++; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; } @@ -2109,9 +2144,14 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; } + + be->dpcm[stream].be_start--; + if (be->dpcm[stream].be_start == 0) + do_trigger = true; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); - if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream)) + if (!do_trigger) continue; spin_lock_irqsave(&fe->card->dpcm_lock, flags); @@ -2123,6 +2163,7 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, if (ret) { spin_lock_irqsave(&fe->card->dpcm_lock, flags); be->dpcm[stream].state = state; + be->dpcm[stream].be_start++; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; } @@ -2134,9 +2175,13 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; } + be->dpcm[stream].be_start--; + if (be->dpcm[stream].be_start == 0) + do_trigger = true; + spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); - if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream)) + if (!do_trigger) continue; spin_lock_irqsave(&fe->card->dpcm_lock, flags); @@ -2148,6 +2193,7 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, if (ret) { spin_lock_irqsave(&fe->card->dpcm_lock, flags); be->dpcm[stream].state = state; + be->dpcm[stream].be_start++; spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); goto end; } From 5ebc10c87a6dbc4264fe3096ee64b32255cb3609 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Tue, 24 Aug 2021 10:21:55 -0500 Subject: [PATCH 3/9] ASoC: soc-pcm: fix BE handling of PAUSE_RELEASE A BE connected to more than one FE, e.g. in a mixer case, can go through the following transitions. play FE1 -> BE state is START pause FE1 -> BE state is PAUSED play FE2 -> BE state is START stop FE2 -> BE state is STOP release FE1 -> BE state is START stop FE1 -> BE state is STOP play FE1 -> BE state is START pause FE1 -> BE state is PAUSED play FE2 -> BE state is START release FE1 -> BE state is START stop FE2 -> BE state is START stop FE1 -> BE state is STOP The existing code for PAUSE_RELEASE only allows for the case where the BE is paused, which clearly would not work in the sequences above. Extend the allowed states to restart the BE when PAUSE_RELEASE is received. Reported-by: Bard Liao Signed-off-by: Pierre-Louis Bossart --- sound/soc/soc-pcm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 616489d985475f..d736e8cfa5c1a9 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -2078,7 +2078,9 @@ int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream, break; case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: spin_lock_irqsave(&fe->card->dpcm_lock, flags); - if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED) { + if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START && + be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP && + be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED) { spin_unlock_irqrestore(&fe->card->dpcm_lock, flags); continue; } From 60b8b69807928ce2b1640ff0a72a58b844b5ec2f Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Tue, 17 Aug 2021 18:02:14 -0500 Subject: [PATCH 4/9] ASoC: SOF: sof-audio: flag errors on pipeline teardown Before suspending, walk through all the widgets to make sure all refcounts are zero. If not, the resume will not work and random errors will be reported. Adding this paranoia check will help identify leaks and broken sequences. Signed-off-by: Pierre-Louis Bossart --- sound/soc/sof/sof-audio.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/sound/soc/sof/sof-audio.c b/sound/soc/sof/sof-audio.c index fb7b5f9b9a9eea..c364689c38d02f 100644 --- a/sound/soc/sof/sof-audio.c +++ b/sound/soc/sof/sof-audio.c @@ -816,6 +816,18 @@ int sof_tear_down_pipelines(struct snd_sof_dev *sdev, bool verify) list_for_each_entry(sroute, &sdev->route_list, list) sroute->setup = false; + /* + * before suspending, make sure the refcounts are all zeroed out. There's no way + * to recover at this point but this will help root cause bad sequences leading to + * more issues on resume + */ + list_for_each_entry(swidget, &sdev->widget_list, list) { + if (swidget->use_count != 0) { + dev_err(sdev->dev, "%s: widget %s is still in use: count %d\n", + __func__, swidget->widget->name, swidget->use_count); + } + } + return 0; } From 4e755533e0c11d60db42642eb184611cd44077ab Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Thu, 26 Aug 2021 13:48:42 -0500 Subject: [PATCH 5/9] Revert "soundwire: intel: trap TRIGGER_SUSPEND in .trigger callback" This reverts commit 048ecd7251508b51a27c54a298a16f3b6cbdff99. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/intel.c | 53 ++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 29 deletions(-) diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index f95c3cc231e2e9..78037ffdb09ba9 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1008,6 +1008,29 @@ static void intel_shutdown(struct snd_pcm_substream *substream, pm_runtime_put_autosuspend(cdns->dev); } +static int intel_component_dais_suspend(struct snd_soc_component *component) +{ + struct sdw_cdns_dma_data *dma; + struct snd_soc_dai *dai; + + for_each_component_dais(component, dai) { + /* + * we don't have a .suspend dai_ops, and we don't have access + * to the substream, so let's mark both capture and playback + * DMA contexts as suspended + */ + dma = dai->playback_dma_data; + if (dma) + dma->suspended = true; + + dma = dai->capture_dma_data; + if (dma) + dma->suspended = true; + } + + return 0; +} + static int intel_pcm_set_sdw_stream(struct snd_soc_dai *dai, void *stream, int direction) { @@ -1036,39 +1059,11 @@ static void *intel_get_sdw_stream(struct snd_soc_dai *dai, return dma->stream; } -static int intel_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai) -{ - struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai); - struct sdw_intel *sdw = cdns_to_intel(cdns); - struct sdw_cdns_dma_data *dma; - - /* - * The .prepare callback is used to deal with xruns and resume operations. In the case - * of xruns, the DMAs and SHIM registers cannot be touched, but for resume operations the - * DMAs and SHIM registers need to be initialized. - * the .trigger callback is used to track the suspend case only. - */ - if (cmd != SNDRV_PCM_TRIGGER_SUSPEND) - return 0; - - dma = snd_soc_dai_get_dma_data(dai, substream); - if (!dma) { - dev_err(dai->dev, "failed to get dma data in %s\n", - __func__); - return -EIO; - } - - dma->suspended = true; - - return intel_free_stream(sdw, substream, dai, sdw->instance); -} - static const struct snd_soc_dai_ops intel_pcm_dai_ops = { .startup = intel_startup, .hw_params = intel_hw_params, .prepare = intel_prepare, .hw_free = intel_hw_free, - .trigger = intel_trigger, .shutdown = intel_shutdown, .set_sdw_stream = intel_pcm_set_sdw_stream, .get_sdw_stream = intel_get_sdw_stream, @@ -1079,7 +1074,6 @@ static const struct snd_soc_dai_ops intel_pdm_dai_ops = { .hw_params = intel_hw_params, .prepare = intel_prepare, .hw_free = intel_hw_free, - .trigger = intel_trigger, .shutdown = intel_shutdown, .set_sdw_stream = intel_pdm_set_sdw_stream, .get_sdw_stream = intel_get_sdw_stream, @@ -1087,6 +1081,7 @@ static const struct snd_soc_dai_ops intel_pdm_dai_ops = { static const struct snd_soc_component_driver dai_component = { .name = "soundwire", + .suspend = intel_component_dais_suspend }; static int intel_create_dai(struct sdw_cdns *cdns, From d0da8ff1ab2dc7db22ad23dfebf2bd057ef513cb Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Fri, 13 Aug 2021 12:03:59 -0500 Subject: [PATCH 6/9] soundwire: stream: make enable/disable/deprepare idempotent The stream management currently flags an 'inconsistent state' error when a change is requested multiple times. This was added on purpose to identify programming mistakes. In hindsight, there was no real reason to fail if the logic at the ASoC-DPCM level invokes the same callback multiple times. It's perfectly acceptable to just return and not flag an error when there is nothing to do. The main concern with the state management is to trap errors such as trying to enable a stream that was not prepared first. This patch suggests allowing the stream functions to be idempotent, i.e. they can be called multiple times. Note that the prepare case was already handling multiple calls, this was added in commit c32464c9393d ("soundwire: stream: only prepare stream when it is configured.") Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/stream.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c index 5d4f6b308ef731..901683a78dad2e 100644 --- a/drivers/soundwire/stream.c +++ b/drivers/soundwire/stream.c @@ -1679,6 +1679,11 @@ int sdw_enable_stream(struct sdw_stream_runtime *stream) sdw_acquire_bus_lock(stream); + if (stream->state == SDW_STREAM_ENABLED) { + ret = 0; + goto state_err; + } + if (stream->state != SDW_STREAM_PREPARED && stream->state != SDW_STREAM_DISABLED) { pr_err("%s: %s: inconsistent state state %d\n", @@ -1762,6 +1767,11 @@ int sdw_disable_stream(struct sdw_stream_runtime *stream) sdw_acquire_bus_lock(stream); + if (stream->state == SDW_STREAM_DISABLED) { + ret = 0; + goto state_err; + } + if (stream->state != SDW_STREAM_ENABLED) { pr_err("%s: %s: inconsistent state state %d\n", __func__, stream->name, stream->state); @@ -1837,6 +1847,11 @@ int sdw_deprepare_stream(struct sdw_stream_runtime *stream) sdw_acquire_bus_lock(stream); + if (stream->state == SDW_STREAM_DEPREPARED) { + ret = 0; + goto state_err; + } + if (stream->state != SDW_STREAM_PREPARED && stream->state != SDW_STREAM_DISABLED) { pr_err("%s: %s: inconsistent state state %d\n", From 06a145bd7209b4f8e5e3ab5a6f6f51c789240f66 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Thu, 19 Aug 2021 16:59:00 -0500 Subject: [PATCH 7/9] soundwire: intel: filter hw_params It's not unusual for ALSA/ASoC hw_params callbacks to be invoked multiple times. This can happen when the application sets different configurations, but also in the case of multiple FEs connected to a single BE, the ASoC-DPCM framework will propagate hw_params on the BE dailink for each FE configuration. Unfortunately this is not supported by the SoundWire 'stream' API today, since it mixes allocation and configurations. In current implementations the SoundWire configurations are fixed, so we can just filter additional calls. If/when the configurations start varying, we will need a complete overhaul of the stream API to split allocation and configurations in two completely separate steps. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/intel.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 78037ffdb09ba9..22784e2129e498 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -846,6 +846,12 @@ static int intel_hw_params(struct snd_pcm_substream *substream, if (!dma) return -EIO; + if (dma->hw_params) { + /* reconfiguration is currently not supported */ + ret = 0; + goto error; + } + ch = params_channels(params); if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) dir = SDW_DATA_DIR_RX; From da72cae6a6accb1e2968ca635116667322c59011 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Wed, 25 Aug 2021 14:23:24 -0500 Subject: [PATCH 8/9] ASoC/soundwire: intel: simplify callbacks for params/hw_free We don't really need to pass a substream to the callback, we only need the direction. No functionality change, only simplification to enable improve suspend with paused streams. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/intel.c | 14 +++++++------- include/linux/soundwire/sdw_intel.h | 4 ++-- sound/soc/sof/intel/hda.c | 6 ++---- 3 files changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 22784e2129e498..d40299e14e4dcf 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -711,7 +711,7 @@ intel_pdi_alh_configure(struct sdw_intel *sdw, struct sdw_cdns_pdi *pdi) } static int intel_params_stream(struct sdw_intel *sdw, - struct snd_pcm_substream *substream, + int stream, struct snd_soc_dai *dai, struct snd_pcm_hw_params *hw_params, int link_id, int alh_stream_id) @@ -719,7 +719,7 @@ static int intel_params_stream(struct sdw_intel *sdw, struct sdw_intel_link_res *res = sdw->link_res; struct sdw_intel_stream_params_data params_data; - params_data.substream = substream; + params_data.stream = stream; /* direction */ params_data.dai = dai; params_data.hw_params = hw_params; params_data.link_id = link_id; @@ -732,14 +732,14 @@ static int intel_params_stream(struct sdw_intel *sdw, } static int intel_free_stream(struct sdw_intel *sdw, - struct snd_pcm_substream *substream, + int stream, struct snd_soc_dai *dai, int link_id) { struct sdw_intel_link_res *res = sdw->link_res; struct sdw_intel_stream_free_data free_data; - free_data.substream = substream; + free_data.stream = stream; /* direction */ free_data.dai = dai; free_data.link_id = link_id; @@ -882,7 +882,7 @@ static int intel_hw_params(struct snd_pcm_substream *substream, dma->hw_params = params; /* Inform DSP about PDI stream number */ - ret = intel_params_stream(sdw, substream, dai, params, + ret = intel_params_stream(sdw, substream->stream, dai, params, sdw->instance, pdi->intel_alh_id); if (ret) @@ -959,7 +959,7 @@ static int intel_prepare(struct snd_pcm_substream *substream, sdw_cdns_config_stream(cdns, ch, dir, dma->pdi); /* Inform DSP about PDI stream number */ - ret = intel_params_stream(sdw, substream, dai, + ret = intel_params_stream(sdw, substream->stream, dai, dma->hw_params, sdw->instance, dma->pdi->intel_alh_id); @@ -993,7 +993,7 @@ intel_hw_free(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) return ret; } - ret = intel_free_stream(sdw, substream, dai, sdw->instance); + ret = intel_free_stream(sdw, substream->stream, dai, sdw->instance); if (ret < 0) { dev_err(dai->dev, "intel_free_stream: failed %d\n", ret); return ret; diff --git a/include/linux/soundwire/sdw_intel.h b/include/linux/soundwire/sdw_intel.h index 8a463b8fc12ad9..67e0d3e750b5c9 100644 --- a/include/linux/soundwire/sdw_intel.h +++ b/include/linux/soundwire/sdw_intel.h @@ -92,7 +92,7 @@ * firmware. */ struct sdw_intel_stream_params_data { - struct snd_pcm_substream *substream; + int stream; struct snd_soc_dai *dai; struct snd_pcm_hw_params *hw_params; int link_id; @@ -105,7 +105,7 @@ struct sdw_intel_stream_params_data { * firmware. */ struct sdw_intel_stream_free_data { - struct snd_pcm_substream *substream; + int stream; struct snd_soc_dai *dai; int link_id; }; diff --git a/sound/soc/sof/intel/hda.c b/sound/soc/sof/intel/hda.c index fe656d29f772a1..1ef433137861cb 100644 --- a/sound/soc/sof/intel/hda.c +++ b/sound/soc/sof/intel/hda.c @@ -181,12 +181,11 @@ static int sdw_dai_config_ipc(struct snd_sof_dev *sdev, static int sdw_params_stream(struct device *dev, struct sdw_intel_stream_params_data *params_data) { - struct snd_pcm_substream *substream = params_data->substream; struct snd_sof_dev *sdev = dev_get_drvdata(dev); struct snd_soc_dai *d = params_data->dai; struct snd_soc_dapm_widget *w; - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + if (params_data->stream == SNDRV_PCM_STREAM_PLAYBACK) w = d->playback_widget; else w = d->capture_widget; @@ -198,12 +197,11 @@ static int sdw_params_stream(struct device *dev, static int sdw_free_stream(struct device *dev, struct sdw_intel_stream_free_data *free_data) { - struct snd_pcm_substream *substream = free_data->substream; struct snd_sof_dev *sdev = dev_get_drvdata(dev); struct snd_soc_dai *d = free_data->dai; struct snd_soc_dapm_widget *w; - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + if (free_data->stream == SNDRV_PCM_STREAM_PLAYBACK) w = d->playback_widget; else w = d->capture_widget; From 0559ef6a73968d48cca0c0abc3bbad68cb72a4fd Mon Sep 17 00:00:00 2001 From: Ranjani Sridharan Date: Tue, 29 Jun 2021 22:13:04 -0700 Subject: [PATCH 9/9] soundwire: intel: improve suspend flows This patch provides both a simplification of the suspend flows and a better balanced operation during suspend/resume transition, as part of the transition of Sound Open Firmware (SOF) to dynamic pipelines: the DSP resources are only enabled when required instead of enabled on startup. The exiting code relies on a convoluted way of dealing with suspend signals. Since there is no .suspend DAI callback, we used the component .suspend and marked all the component DAI dmas as 'suspended'. The information was used in the .prepare stage to differentiate resume operations from xrun handling, and only reinitialize SHIM registers and DMA in the former case. While this solution has been working reliably for about 2 years, there is a much better solution consisting in trapping the TRIGGER_SUSPEND in the .trigger DAI ops. The DMA is still marked in the same way for the .prepare op to run, but in addition the callbacks sent to DSP firmware are now balanced. Normal operation: hw_params -> intel_params_stream hw_free -> intel_free_stream suspend -> intel_free_stream prepare -> intel_params_stream This balanced operation was not required with existing SOF firmware relying on static pipelines instantiated at every boot. With the on-going transition to dynamic pipelines, it's however a requirement to keep the use count for the DAI widget balanced across all transitions. The component suspend is not removed but instead modified to deal with a corner case: when a substream is PAUSED, the ALSA core does not throw the TRIGGER_SUSPEND. This is problematic since the refcount for all pipelines and widgets is not balanced, leading to issues on resume. The trigger callback keeps track of the 'paused' state with a new flag, which is tested during the component suspend called later to release the remaining DSP resources. These resources will be re-enabled in the .prepare step. The IPC used in the TRIGGER_SUSPEND to release DSP resources is not a problem since the BE dailink is already marked as non-atomic. Co-developed-by: Pierre-Louis Bossart Signed-off-by: Pierre-Louis Bossart Signed-off-by: Ranjani Sridharan --- drivers/soundwire/cadence_master.h | 2 + drivers/soundwire/intel.c | 113 +++++++++++++++++++++++------ 2 files changed, 91 insertions(+), 24 deletions(-) diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index e587aede63bf05..aa4b9b0eb2a893 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -86,6 +86,7 @@ struct sdw_cdns_stream_config { * @link_id: Master link id * @hw_params: hw_params to be applied in .prepare step * @suspended: status set when suspended, to be used in .prepare + * @paused: status set in .trigger, to be used in suspend */ struct sdw_cdns_dma_data { char *name; @@ -96,6 +97,7 @@ struct sdw_cdns_dma_data { int link_id; struct snd_pcm_hw_params *hw_params; bool suspended; + bool paused; }; /** diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index d40299e14e4dcf..61e2d3c5611320 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -877,6 +877,7 @@ static int intel_hw_params(struct snd_pcm_substream *substream, sdw_cdns_config_stream(cdns, ch, dir, pdi); /* store pdi and hw_params, may be needed in prepare step */ + dma->paused = false; dma->suspended = false; dma->pdi = pdi; dma->hw_params = params; @@ -1014,29 +1015,6 @@ static void intel_shutdown(struct snd_pcm_substream *substream, pm_runtime_put_autosuspend(cdns->dev); } -static int intel_component_dais_suspend(struct snd_soc_component *component) -{ - struct sdw_cdns_dma_data *dma; - struct snd_soc_dai *dai; - - for_each_component_dais(component, dai) { - /* - * we don't have a .suspend dai_ops, and we don't have access - * to the substream, so let's mark both capture and playback - * DMA contexts as suspended - */ - dma = dai->playback_dma_data; - if (dma) - dma->suspended = true; - - dma = dai->capture_dma_data; - if (dma) - dma->suspended = true; - } - - return 0; -} - static int intel_pcm_set_sdw_stream(struct snd_soc_dai *dai, void *stream, int direction) { @@ -1065,11 +1043,97 @@ static void *intel_get_sdw_stream(struct snd_soc_dai *dai, return dma->stream; } +static int intel_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai) +{ + struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai); + struct sdw_intel *sdw = cdns_to_intel(cdns); + struct sdw_cdns_dma_data *dma; + int ret; + + dma = snd_soc_dai_get_dma_data(dai, substream); + if (!dma) { + dev_err(dai->dev, "failed to get dma data in %s\n", + __func__); + return -EIO; + } + + switch (cmd) { + case SNDRV_PCM_TRIGGER_SUSPEND: + + /* + * The .prepare callback is used to deal with xruns and resume operations. + * In the case of xruns, the DMAs and SHIM registers cannot be touched, + * but for resume operations the DMAs and SHIM registers need to be initialized. + * the .trigger callback is used to track the suspend case only. + */ + + dma->suspended = true; + + ret = intel_free_stream(sdw, substream->stream, dai, sdw->instance); + break; + + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + dma->paused = true; + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + dma->paused = false; + break; + default: + break; + } + + return ret; +} + +static int intel_component_dais_suspend(struct snd_soc_component *component) +{ + struct snd_soc_dai *dai; + + /* + * In the corner case where a SUSPEND happens during a PAUSE, the ALSA core + * does not throw the TRIGGER_SUSPEND. This leaves the DAIs in an unbalanced state. + * Since the component suspend is called last, we can trap this corner case + * and force the DAIs to release their resources. + */ + for_each_component_dais(component, dai) { + struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai); + struct sdw_intel *sdw = cdns_to_intel(cdns); + struct sdw_cdns_dma_data *dma; + int stream; + int ret; + + dma = dai->playback_dma_data; + stream = SNDRV_PCM_STREAM_PLAYBACK; + if (!dma) { + dma = dai->capture_dma_data; + stream = SNDRV_PCM_STREAM_CAPTURE; + } + + if (!dma) + continue; + + if (dma->suspended) + continue; + + if (dma->paused) { + dma->suspended = true; + + ret = intel_free_stream(sdw, stream, dai, sdw->instance); + if (ret < 0) + return ret; + } + } + + return 0; +} + static const struct snd_soc_dai_ops intel_pcm_dai_ops = { .startup = intel_startup, .hw_params = intel_hw_params, .prepare = intel_prepare, .hw_free = intel_hw_free, + .trigger = intel_trigger, .shutdown = intel_shutdown, .set_sdw_stream = intel_pcm_set_sdw_stream, .get_sdw_stream = intel_get_sdw_stream, @@ -1080,6 +1144,7 @@ static const struct snd_soc_dai_ops intel_pdm_dai_ops = { .hw_params = intel_hw_params, .prepare = intel_prepare, .hw_free = intel_hw_free, + .trigger = intel_trigger, .shutdown = intel_shutdown, .set_sdw_stream = intel_pdm_set_sdw_stream, .get_sdw_stream = intel_get_sdw_stream, @@ -1087,7 +1152,7 @@ static const struct snd_soc_dai_ops intel_pdm_dai_ops = { static const struct snd_soc_component_driver dai_component = { .name = "soundwire", - .suspend = intel_component_dais_suspend + .suspend = intel_component_dais_suspend, }; static int intel_create_dai(struct sdw_cdns *cdns,