From 93c2a8ea2454b7b14eb378a58cad8a83c0ffc903 Mon Sep 17 00:00:00 2001 From: Richard Fitzgerald Date: Thu, 16 Jul 2026 14:20:44 +0100 Subject: [PATCH 1/2] ASoC: cs35l56: Fix potential probe() deadlock On I2C/SPI call cs35l56_init() before calling snd_soc_register_component() to prevent the potential for a deadlock on init_completion. For most buses all the hardware would be ready when probe() returns, but on SoundWire, probe() must return before the SoundWire bus driver will enumerate the device. All access to the registers must be deferred until the driver receives an ATTACHED notification. But anything that could return -EPROBE_DEFER must be called during probe, and that includes snd_soc_register_component(). Because of that, on SoundWire the ASoC component can be created before the registers are accssible, so cs35l56_component_probe() waits for init_completion to signal that the registers are accessible. On I2C/SPI this 2-stage startup isn't required so their probe() functions simply called cs35l56_common_probe() and then cs35l56_init(). The problem with this was that snd_soc_register_component() was still called early. If this triggered ASoC to create the card, ASoC would call cs35l56_component_probe() which waits on init_completion - but this would be running inside the cs35l56 driver probe() so blocking it from reaching the code that signals init_completion, causing a deadlock. Fixes: e496112529006 ("ASoC: cs35l56: Add driver for Cirrus Logic CS35L56") Reported-by: Salman S. Tahir Closes: https://lore.kernel.org/linux-sound/95c21574-97d5-4311-9263-9e174d22d22c@opensource.cirrus.com/T/#u Tested-by: Salman S. Tahir Signed-off-by: Richard Fitzgerald Link: https://patch.msgid.link/20260716132045.1469156-2-rf@opensource.cirrus.com Signed-off-by: Mark Brown --- sound/soc/codecs/cs35l56-i2c.c | 4 +--- sound/soc/codecs/cs35l56-spi.c | 4 +--- sound/soc/codecs/cs35l56.c | 15 +++++++++++++++ 3 files changed, 17 insertions(+), 6 deletions(-) diff --git a/sound/soc/codecs/cs35l56-i2c.c b/sound/soc/codecs/cs35l56-i2c.c index 0f64ab628b03..4f6ddf1c5a3f 100644 --- a/sound/soc/codecs/cs35l56-i2c.c +++ b/sound/soc/codecs/cs35l56-i2c.c @@ -55,9 +55,7 @@ static int cs35l56_i2c_probe(struct i2c_client *client) if (ret != 0) return ret; - ret = cs35l56_init(cs35l56); - if (ret == 0) - ret = cs35l56_irq_request(&cs35l56->base, client->irq); + ret = cs35l56_irq_request(&cs35l56->base, client->irq); if (ret < 0) cs35l56_remove(cs35l56); diff --git a/sound/soc/codecs/cs35l56-spi.c b/sound/soc/codecs/cs35l56-spi.c index 9bc9b7c98390..b1eb924a5b6c 100644 --- a/sound/soc/codecs/cs35l56-spi.c +++ b/sound/soc/codecs/cs35l56-spi.c @@ -44,9 +44,7 @@ static int cs35l56_spi_probe(struct spi_device *spi) if (ret != 0) return ret; - ret = cs35l56_init(cs35l56); - if (ret == 0) - ret = cs35l56_irq_request(&cs35l56->base, spi->irq); + ret = cs35l56_irq_request(&cs35l56->base, spi->irq); if (ret < 0) cs35l56_remove(cs35l56); diff --git a/sound/soc/codecs/cs35l56.c b/sound/soc/codecs/cs35l56.c index 570a68829ccd..fea4362e74cd 100644 --- a/sound/soc/codecs/cs35l56.c +++ b/sound/soc/codecs/cs35l56.c @@ -2008,6 +2008,16 @@ int cs35l56_common_probe(struct cs35l56_private *cs35l56) goto err; } + /* + * On SoundWire the cs35l56_init() cannot be run until after the + * device has been enumerated by the SoundWire core. + */ + if (!cs35l56->sdw_peripheral) { + ret = cs35l56_init(cs35l56); + if (ret) + goto err_remove_wm_adsp; + } + ret = snd_soc_register_component(cs35l56->base.dev, &soc_component_dev_cs35l56, cs35l56_dai, ARRAY_SIZE(cs35l56_dai)); @@ -2022,6 +2032,11 @@ err_remove_wm_adsp: wm_adsp2_remove(&cs35l56->dsp); err: + if (pm_runtime_enabled(cs35l56->base.dev)) { + pm_runtime_dont_use_autosuspend(cs35l56->base.dev); + pm_runtime_disable(cs35l56->base.dev); + } + gpiod_set_value_cansleep(cs35l56->base.reset_gpio, 0); regulator_bulk_disable(ARRAY_SIZE(cs35l56->supplies), cs35l56->supplies); From e0bffb63a2eda0af82ed7e6357ac67c2db990c21 Mon Sep 17 00:00:00 2001 From: Richard Fitzgerald Date: Thu, 16 Jul 2026 14:20:45 +0100 Subject: [PATCH 2/2] ASoC: cs35l56: Use complete_all() to signal init_completion In cs35l56_init() use complete_all() to signal init_completion instead of complete(). cs35l56_init() was signaling init_completion using the complete() function. This only releases ONE waiter. If cs35l56_component_probe() was called multiple times the first time would consume that one signal, then future calls would timeout waiting for the completion. This could happen if: - The component is probed, removed, then probed again without the cs35l56 module being removed. - A call to component_probe() returns an error and ASoC calls it again later. It should use complete_all() so that after it has been signaled it will allow any code that waits on it to continue immediately. The one case where the driver must wait for initialization to run again is when waiting for a reboot after firmware download, and here the code correctly calls reinit_completion() first. Fixes: e496112529006 ("ASoC: cs35l56: Add driver for Cirrus Logic CS35L56") Signed-off-by: Richard Fitzgerald Link: https://patch.msgid.link/20260716132045.1469156-3-rf@opensource.cirrus.com Signed-off-by: Mark Brown --- sound/soc/codecs/cs35l56.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/soc/codecs/cs35l56.c b/sound/soc/codecs/cs35l56.c index fea4362e74cd..063ef7a70de0 100644 --- a/sound/soc/codecs/cs35l56.c +++ b/sound/soc/codecs/cs35l56.c @@ -2123,7 +2123,7 @@ post_soft_reset: return dev_err_probe(cs35l56->base.dev, ret, "Failed to write ASP1_CONTROL3\n"); cs35l56->base.init_done = true; - complete(&cs35l56->init_completion); + complete_all(&cs35l56->init_completion); return 0; }