HID: intel-ish-hid: ishtp: add helper function for client search

Add helper function ishtp_fw_cl_get_client() for client driver searching
client information to hide internal details from callers.

Signed-off-by: Even Xu <even.xu@intel.com>
Reviewed-by: Andriy Shevchenko <andriy.shevchenko@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/intel-ish-hid/ishtp/bus.c

@@ -148,6 +148,31 @@ int ishtp_fw_cl_by_uuid(struct ishtp_device *dev, const uuid_le *uuid)
 }
 EXPORT_SYMBOL(ishtp_fw_cl_by_uuid);
 
+/**
+ * ishtp_fw_cl_get_client() - return client information to client
+ * @dev: the ishtp device structure
+ * @uuid: uuid of the client to search
+ *
+ * Search firmware client using UUID and reture related client information.
+ *
+ * Return: pointer of client information on success, NULL on failure.
+ */
+struct ishtp_fw_client *ishtp_fw_cl_get_client(struct ishtp_device *dev,
+						const uuid_le *uuid)
+{
+	int i;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->fw_clients_lock, flags);
+	i = ishtp_fw_cl_by_uuid(dev, uuid);
+	spin_unlock_irqrestore(&dev->fw_clients_lock, flags);
+	if (i < 0 || dev->fw_clients[i].props.fixed_address)
+		return NULL;
+
+	return &dev->fw_clients[i];
+}
+EXPORT_SYMBOL(ishtp_fw_cl_get_client);
+
 /**
  * ishtp_fw_cl_by_id() - return index to fw_clients for client_id
  * @dev: the ishtp device structure

drivers/hid/intel-ish-hid/ishtp/bus.h

@@ -113,5 +113,7 @@ void	ishtp_cl_driver_unregister(struct ishtp_cl_driver *driver);
 int	ishtp_register_event_cb(struct ishtp_cl_device *device,
 				void (*read_cb)(struct ishtp_cl_device *));
 int	ishtp_fw_cl_by_uuid(struct ishtp_device *dev, const uuid_le *cuuid);
+struct	ishtp_fw_client *ishtp_fw_cl_get_client(struct ishtp_device *dev,
+						const uuid_le *uuid);
 
 #endif /* _LINUX_ISHTP_CL_BUS_H */