ASoC: SOF: clients: Add API to manage the module refcount of SOF core

The SOF core module (the device driver of the DSP) needs to be protected
against removal when a client is active and needs the core to be present
during it's active operation.

sof_client_core_moduleget/put can be use by client drivers to manage the
refcount on the core's module to prevent such a case.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

Author: ujfalusi

sound/soc/sof/sof-client.c

@@ -231,6 +231,26 @@ const struct sof_ipc_fw_version *sof_client_get_fw_version(struct sof_client_dev
 }
 EXPORT_SYMBOL_NS_GPL(sof_client_get_fw_version, SND_SOC_SOF_CLIENT);
 
+/* module refcount management of SOF core */
+int sof_client_core_module_get(struct sof_client_dev *cdev)
+{
+	struct snd_sof_dev *sdev = sof_client_dev_to_sof_dev(cdev);
+
+	if (!try_module_get(sdev->dev->driver->owner))
+		return -ENODEV;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(sof_client_core_module_get, SND_SOC_SOF_CLIENT);
+
+void sof_client_core_module_put(struct sof_client_dev *cdev)
+{
+	struct snd_sof_dev *sdev = sof_client_dev_to_sof_dev(cdev);
+
+	module_put(sdev->dev->driver->owner);
+}
+EXPORT_SYMBOL_NS_GPL(sof_client_core_module_put, SND_SOC_SOF_CLIENT);
+
 /* IPC event handling */
 void sof_client_ipc_rx_dispatcher(struct snd_sof_dev *sdev, void *full_msg)
 {

sound/soc/sof/sof-client.h

@@ -42,6 +42,10 @@ struct dentry *sof_client_get_debugfs_root(struct sof_client_dev *cdev);
 struct device *sof_client_get_dma_dev(struct sof_client_dev *cdev);
 const struct sof_ipc_fw_version *sof_client_get_fw_version(struct sof_client_dev *cdev);
 
+/* module refcount management of SOF core */
+int sof_client_core_module_get(struct sof_client_dev *cdev);
+void sof_client_core_module_put(struct sof_client_dev *cdev);
+
 /* IPC notification */
 typedef void (*sof_client_event_callback)(struct sof_client_dev *cdev,
 					  void *full_msg);