ASoC: SOF: sof-client: Add support for clients not managed by pm framework

Some SOF client can be of 'passive' type, meaning that they do not handle
PM framework callbacks by themselves but rely on the auxiliary driver's
suspend and resume callbacks to be notified about the core's suspend or
resume event.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20220210150525.30756-7-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/pm.c

@@ -167,6 +167,9 @@ static int sof_resume(struct device *dev, bool runtime_resume)
 		return ret;
 	}
 
+	/* Notify clients not managed by pm framework about core resume */
+	sof_resume_clients(sdev);
+
 	/* notify DSP of system resume */
 	ret = sof_send_pm_ctx_ipc(sdev, SOF_IPC_PM_CTX_RESTORE);
 	if (ret < 0)
@@ -180,6 +183,7 @@ static int sof_resume(struct device *dev, bool runtime_resume)
 static int sof_suspend(struct device *dev, bool runtime_suspend)
 {
 	struct snd_sof_dev *sdev = dev_get_drvdata(dev);
+	pm_message_t pm_state;
 	u32 target_state = 0;
 	int ret;
 
@@ -205,16 +209,23 @@ static int sof_suspend(struct device *dev, bool runtime_suspend)
 	}
 
 	target_state = snd_sof_dsp_power_target(sdev);
+	pm_state.event = target_state;
 
 	/* Skip to platform-specific suspend if DSP is entering D0 */
-	if (target_state == SOF_DSP_PM_D0)
+	if (target_state == SOF_DSP_PM_D0) {
+		/* Notify clients not managed by pm framework about core suspend */
+		sof_suspend_clients(sdev, pm_state);
 		goto suspend;
+	}
 
 	sof_tear_down_pipelines(sdev, false);
 
 	/* release trace */
 	snd_sof_release_trace(sdev);
 
+	/* Notify clients not managed by pm framework about core suspend */
+	sof_suspend_clients(sdev, pm_state);
+
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE)
 	/* cache debugfs contents during runtime suspend */
 	if (runtime_suspend)

sound/soc/sof/sof-client.c

@@ -169,6 +169,52 @@ int sof_client_ipc_tx_message(struct sof_client_dev *cdev, void *ipc_msg,
 }
 EXPORT_SYMBOL_NS_GPL(sof_client_ipc_tx_message, SND_SOC_SOF_CLIENT);
 
+int sof_suspend_clients(struct snd_sof_dev *sdev, pm_message_t state)
+{
+	struct auxiliary_driver *adrv;
+	struct sof_client_dev *cdev;
+
+	mutex_lock(&sdev->ipc_client_mutex);
+
+	list_for_each_entry(cdev, &sdev->ipc_client_list, list) {
+		/* Skip devices without loaded driver */
+		if (!cdev->auxdev.dev.driver)
+			continue;
+
+		adrv = to_auxiliary_drv(cdev->auxdev.dev.driver);
+		if (adrv->suspend)
+			adrv->suspend(&cdev->auxdev, state);
+	}
+
+	mutex_unlock(&sdev->ipc_client_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(sof_suspend_clients, SND_SOC_SOF_CLIENT);
+
+int sof_resume_clients(struct snd_sof_dev *sdev)
+{
+	struct auxiliary_driver *adrv;
+	struct sof_client_dev *cdev;
+
+	mutex_lock(&sdev->ipc_client_mutex);
+
+	list_for_each_entry(cdev, &sdev->ipc_client_list, list) {
+		/* Skip devices without loaded driver */
+		if (!cdev->auxdev.dev.driver)
+			continue;
+
+		adrv = to_auxiliary_drv(cdev->auxdev.dev.driver);
+		if (adrv->resume)
+			adrv->resume(&cdev->auxdev);
+	}
+
+	mutex_unlock(&sdev->ipc_client_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(sof_resume_clients, SND_SOC_SOF_CLIENT);
+
 struct dentry *sof_client_get_debugfs_root(struct sof_client_dev *cdev)
 {
 	return cdev->sdev->debugfs_root;

sound/soc/sof/sof-priv.h

@@ -653,6 +653,8 @@ int sof_register_clients(struct snd_sof_dev *sdev);
 void sof_unregister_clients(struct snd_sof_dev *sdev);
 void sof_client_ipc_rx_dispatcher(struct snd_sof_dev *sdev, void *msg_buf);
 void sof_client_fw_state_dispatcher(struct snd_sof_dev *sdev);
+int sof_suspend_clients(struct snd_sof_dev *sdev, pm_message_t state);
+int sof_resume_clients(struct snd_sof_dev *sdev);
 #else /* CONFIG_SND_SOC_SOF_CLIENT */
 static inline int sof_client_dev_register(struct snd_sof_dev *sdev, const char *name,
 					  u32 id, const void *data, size_t size)
@@ -681,6 +683,16 @@ static inline void sof_client_ipc_rx_dispatcher(struct snd_sof_dev *sdev, void *
 static inline void sof_client_fw_state_dispatcher(struct snd_sof_dev *sdev)
 {
 }
+
+static inline int sof_suspend_clients(struct snd_sof_dev *sdev, pm_message_t state)
+{
+	return 0;
+}
+
+static inline int sof_resume_clients(struct snd_sof_dev *sdev)
+{
+	return 0;
+}
 #endif /* CONFIG_SND_SOC_SOF_CLIENT */
 
 #endif