From 73942a6ea26bd7e02b7c260b8b7aa942397be894 Mon Sep 17 00:00:00 2001 From: Stefan Binding Date: Tue, 24 Feb 2026 16:18:05 +0000 Subject: [PATCH 1/4] firmware: cs_dsp: Add API to hibernate the DSP For some parts, the DSP is kept running when in low power mode (hibernation), leaving the firmware ALSA controls enabled, but the registers are inaccessible. Attempts to access volatile firmware controls whilst in this state would produce errors in the kernel log due to a regmap_raw_read() into DSP registers whilst the regmap is in cache_only. To remove this error log, add a hibernating flag to indicate that the controls are inaccessible, so we no longer try to read or write to the registers whilst the regmap is in cache_only. This would still produce an error when trying to read or write to these controls, but this would be a different error (-EPERM instead of -EBUSY), and would not produce a spurious error log in the kernel. Upon wake from hibernation, the control caches are re-synced to the hardware, if the DSP is running. Signed-off-by: Stefan Binding Link: https://patch.msgid.link/20260224161821.93365-2-sbinding@opensource.cirrus.com Reviewed-by: Richard Fitzgerald Signed-off-by: Mark Brown --- drivers/firmware/cirrus/cs_dsp.c | 49 +++++++++++++++++++++++--- include/linux/firmware/cirrus/cs_dsp.h | 3 ++ 2 files changed, 48 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/cirrus/cs_dsp.c b/drivers/firmware/cirrus/cs_dsp.c index b4f1c01e3b5b..f9d8a883900d 100644 --- a/drivers/firmware/cirrus/cs_dsp.c +++ b/drivers/firmware/cirrus/cs_dsp.c @@ -515,6 +515,7 @@ void cs_dsp_init_debugfs(struct cs_dsp *dsp, struct dentry *debugfs_root) debugfs_create_bool("booted", 0444, root, &dsp->booted); debugfs_create_bool("running", 0444, root, &dsp->running); + debugfs_create_bool("hibernating", 0444, root, &dsp->hibernating); debugfs_create_x32("fw_id", 0444, root, &dsp->fw_id); debugfs_create_x32("fw_version", 0444, root, &dsp->fw_id_version); @@ -703,7 +704,7 @@ int cs_dsp_coeff_write_acked_control(struct cs_dsp_coeff_ctl *ctl, unsigned int lockdep_assert_held(&dsp->pwr_lock); - if (!dsp->running) + if (!dsp->running || dsp->hibernating) return -EPERM; ret = cs_dsp_coeff_base_reg(ctl, ®, 0); @@ -827,7 +828,7 @@ int cs_dsp_coeff_write_ctrl(struct cs_dsp_coeff_ctl *ctl, } ctl->set = 1; - if (ctl->enabled && ctl->dsp->running) + if (ctl->enabled && ctl->dsp->running && !ctl->dsp->hibernating) ret = cs_dsp_coeff_write_ctrl_raw(ctl, off, buf, len); if (ret < 0) @@ -920,12 +921,12 @@ int cs_dsp_coeff_read_ctrl(struct cs_dsp_coeff_ctl *ctl, return -EINVAL; if (ctl->flags & WMFW_CTL_FLAG_VOLATILE) { - if (ctl->enabled && ctl->dsp->running) + if (ctl->enabled && ctl->dsp->running && !ctl->dsp->hibernating) return cs_dsp_coeff_read_ctrl_raw(ctl, off, buf, len); else return -EPERM; } else { - if (!ctl->flags && ctl->enabled && ctl->dsp->running) + if (!ctl->flags && ctl->enabled && ctl->dsp->running && !ctl->dsp->hibernating) ret = cs_dsp_coeff_read_ctrl_raw(ctl, 0, ctl->cache, ctl->len); if (buf != ctl->cache) @@ -1108,6 +1109,44 @@ static int cs_dsp_create_control(struct cs_dsp *dsp, return ret; } + +/** + * cs_dsp_hibernate() - Disable or enable all controls for a DSP + * @dsp: pointer to DSP structure + * @hibernate: whether to set controls to cache only mode + * + * When @hibernate is true, the DSP is entering hibernation mode where the + * regmap is inaccessible, and all controls become cache only. + * When @hibernate is false, the DSP has exited hibernation mode. If the DSP + * is running, all controls are re-synced to the DSP. + * + */ +void cs_dsp_hibernate(struct cs_dsp *dsp, bool hibernate) +{ + mutex_lock(&dsp->pwr_lock); + + if (!dsp->running) { + cs_dsp_dbg(dsp, "Cannot hibernate, DSP not running\n"); + goto out; + } + + if (dsp->hibernating == hibernate) + goto out; + + cs_dsp_dbg(dsp, "Set hibernating to %d\n", hibernate); + dsp->hibernating = hibernate; + + if (!dsp->hibernating && dsp->running) { + int ret = cs_dsp_coeff_sync_controls(dsp); + + if (ret) + cs_dsp_err(dsp, "Error syncing controls: %d\n", ret); + } +out: + mutex_unlock(&dsp->pwr_lock); +} +EXPORT_SYMBOL_NS_GPL(cs_dsp_hibernate, "FW_CS_DSP"); + struct cs_dsp_coeff_parsed_alg { int id; const u8 *name; @@ -2498,6 +2537,7 @@ int cs_dsp_adsp1_power_up(struct cs_dsp *dsp, goto err_ena; dsp->booted = true; + dsp->hibernating = false; /* Start the core running */ regmap_update_bits(dsp->regmap, dsp->base + ADSP1_CONTROL_30, @@ -2776,6 +2816,7 @@ int cs_dsp_power_up(struct cs_dsp *dsp, dsp->ops->disable_core(dsp); dsp->booted = true; + dsp->hibernating = false; mutex_unlock(&dsp->pwr_lock); diff --git a/include/linux/firmware/cirrus/cs_dsp.h b/include/linux/firmware/cirrus/cs_dsp.h index 0ec1cdc5585d..4e3baa557068 100644 --- a/include/linux/firmware/cirrus/cs_dsp.h +++ b/include/linux/firmware/cirrus/cs_dsp.h @@ -179,6 +179,7 @@ struct cs_dsp { bool booted; bool running; + bool hibernating; struct list_head ctl_list; @@ -354,4 +355,6 @@ int cs_dsp_chunk_write(struct cs_dsp_chunk *ch, int nbits, u32 val); int cs_dsp_chunk_flush(struct cs_dsp_chunk *ch); int cs_dsp_chunk_read(struct cs_dsp_chunk *ch, int nbits); +void cs_dsp_hibernate(struct cs_dsp *dsp, bool hibernating); + #endif From 6394a52c90c4abd10c8265983ec1f53207cd283e Mon Sep 17 00:00:00 2001 From: Stefan Binding Date: Tue, 24 Feb 2026 16:18:06 +0000 Subject: [PATCH 2/4] ASoC: codecs: wm_adsp: Allow wm_adsp to hibernate without stopping DSP Some parts do not stop the DSP core before runtime suspend, however, this leaves the DSP controls enabled and accessible whilst the part is suspended and the regmap is cache_only. Add new APIs to allow for the DSP to hibernate when the part is suspended, and the DSP is not shut down. Signed-off-by: Stefan Binding Reviewed-by: Richard Fitzgerald Link: https://patch.msgid.link/20260224161821.93365-3-sbinding@opensource.cirrus.com Signed-off-by: Mark Brown --- sound/soc/codecs/wm_adsp.c | 6 ++++++ sound/soc/codecs/wm_adsp.h | 1 + 2 files changed, 7 insertions(+) diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c index 2e23848e1dce..d95b54275b5e 100644 --- a/sound/soc/codecs/wm_adsp.c +++ b/sound/soc/codecs/wm_adsp.c @@ -1100,6 +1100,12 @@ void wm_adsp_stop(struct wm_adsp *dsp) } EXPORT_SYMBOL_GPL(wm_adsp_stop); +void wm_adsp_hibernate(struct wm_adsp *dsp, bool hibernate) +{ + cs_dsp_hibernate(&dsp->cs_dsp, hibernate); +} +EXPORT_SYMBOL_GPL(wm_adsp_hibernate); + int wm_adsp_event(struct snd_soc_dapm_widget *w, struct snd_kcontrol *kcontrol, int event) { diff --git a/sound/soc/codecs/wm_adsp.h b/sound/soc/codecs/wm_adsp.h index 8035fda71f8d..a9118be793d7 100644 --- a/sound/soc/codecs/wm_adsp.h +++ b/sound/soc/codecs/wm_adsp.h @@ -103,6 +103,7 @@ irqreturn_t wm_halo_wdt_expire(int irq, void *data); int wm_adsp_run(struct wm_adsp *dsp); void wm_adsp_stop(struct wm_adsp *dsp); +void wm_adsp_hibernate(struct wm_adsp *dsp, bool hibernate); int wm_adsp_event(struct snd_soc_dapm_widget *w, struct snd_kcontrol *kcontrol, int event); From 4d80c0dbcda551b8b86ff14c6ae93026993970b2 Mon Sep 17 00:00:00 2001 From: Stefan Binding Date: Tue, 24 Feb 2026 16:18:07 +0000 Subject: [PATCH 3/4] ASoC: cs35l41: Hibernate wm_adsp on runtime suspend When the CS35L41 driver suspends, it is put into hibernation, and the regmap goes into cache_only, but the firmware is still running, and wm_adsp is not stopped. If userspace attempts to read a firmware control, it will perform a regmap_raw_read() and this will produce an error in the kernel log. To prevent spurious errors, put the DSP into hibernation which prevents access to the hardware for the ALSA controls. Signed-off-by: Stefan Binding Link: https://patch.msgid.link/20260224161821.93365-4-sbinding@opensource.cirrus.com Signed-off-by: Mark Brown --- sound/soc/codecs/cs35l41.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/sound/soc/codecs/cs35l41.c b/sound/soc/codecs/cs35l41.c index ee56dfceedeb..b2a076706c79 100644 --- a/sound/soc/codecs/cs35l41.c +++ b/sound/soc/codecs/cs35l41.c @@ -1404,6 +1404,7 @@ static int cs35l41_runtime_suspend(struct device *dev) if (!cs35l41->dsp.preloaded || !cs35l41->dsp.cs_dsp.running) return 0; + wm_adsp_hibernate(&cs35l41->dsp, true); cs35l41_enter_hibernate(dev, cs35l41->regmap, cs35l41->hw_cfg.bst_type); regcache_cache_only(cs35l41->regmap, true); @@ -1432,10 +1433,14 @@ static int cs35l41_runtime_resume(struct device *dev) cs35l41_test_key_unlock(cs35l41->dev, cs35l41->regmap); ret = regcache_sync(cs35l41->regmap); cs35l41_test_key_lock(cs35l41->dev, cs35l41->regmap); + + wm_adsp_hibernate(&cs35l41->dsp, false); + if (ret) { dev_err(cs35l41->dev, "Failed to restore register cache: %d\n", ret); return ret; } + cs35l41_init_boost(cs35l41->dev, cs35l41->regmap, &cs35l41->hw_cfg); return 0; From 17c6bf433742e0c1ff5ce175145877c0194e4a7a Mon Sep 17 00:00:00 2001 From: Ricardo Rivera-Matos Date: Tue, 24 Feb 2026 16:18:08 +0000 Subject: [PATCH 4/4] ASoC: cs35l45: Hibernate wm_adsp on runtime suspend When the CS35L45 driver suspends, it is put into hibernation, and the regmap goes into cache_only, but the firmware is still running, and wm_adsp is not stopped. If userspace attempts to read a firmware control, it will perform a regmap_raw_read() and this will produce an error in the kernel log. To prevent spurious errors, put the DSP into hibernation which prevents access to the hardware for the ALSA controls. Signed-off-by: Ricardo Rivera-Matos Signed-off-by: Stefan Binding Link: https://patch.msgid.link/20260224161821.93365-5-sbinding@opensource.cirrus.com Signed-off-by: Mark Brown --- sound/soc/codecs/cs35l45.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/sound/soc/codecs/cs35l45.c b/sound/soc/codecs/cs35l45.c index 7aa558d6362f..a032bb23b4ac 100644 --- a/sound/soc/codecs/cs35l45.c +++ b/sound/soc/codecs/cs35l45.c @@ -984,6 +984,7 @@ static int cs35l45_runtime_suspend(struct device *dev) if (!cs35l45->dsp.preloaded || !cs35l45->dsp.cs_dsp.running) return 0; + wm_adsp_hibernate(&cs35l45->dsp, true); cs35l45_enter_hibernate(cs35l45); regcache_cache_only(cs35l45->regmap, true); @@ -1014,6 +1015,8 @@ static int cs35l45_runtime_resume(struct device *dev) if (ret != 0) dev_warn(cs35l45->dev, "regcache_sync failed: %d\n", ret); + wm_adsp_hibernate(&cs35l45->dsp, false); + /* Clear global error status */ regmap_clear_bits(cs35l45->regmap, CS35L45_ERROR_RELEASE, CS35L45_GLOBAL_ERR_RLS_MASK); regmap_set_bits(cs35l45->regmap, CS35L45_ERROR_RELEASE, CS35L45_GLOBAL_ERR_RLS_MASK);