diff --git a/drivers/input/serio/ams_delta_serio.c b/drivers/input/serio/ams_delta_serio.c
index a1c3148979511a23865b5d817ed52d7dc9a2ff7b..1c0be299f17904b2cc23ebd18b7068b0854b2c9a 100644
--- a/drivers/input/serio/ams_delta_serio.c
+++ b/drivers/input/serio/ams_delta_serio.c
@@ -89,11 +89,6 @@ static irqreturn_t ams_delta_serio_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static int ams_delta_serio_write(struct serio *serio, u8 data)
-{
-	return -EINVAL;
-}
-
 static int ams_delta_serio_open(struct serio *serio)
 {
 	struct ams_delta_serio *priv = serio->port_data;
@@ -162,7 +157,6 @@ static int ams_delta_serio_init(struct platform_device *pdev)
 	priv->serio = serio;
 
 	serio->id.type = SERIO_8042;
-	serio->write = ams_delta_serio_write;
 	serio->open = ams_delta_serio_open;
 	serio->close = ams_delta_serio_close;
 	strlcpy(serio->name, "AMS DELTA keyboard adapter", sizeof(serio->name));
diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
index 8d229a11bb6bfb8f25257e82c350fc140adb4f34..29f491082926a3e317e601f2fe2c3f966b8b0126 100644
--- a/drivers/input/serio/serio.c
+++ b/drivers/input/serio/serio.c
@@ -694,11 +694,6 @@ EXPORT_SYMBOL(serio_reconnect);
  */
 void __serio_register_port(struct serio *serio, struct module *owner)
 {
-	if (!serio->write) {
-		pr_err("%s: refusing to register %s without write method\n",
-		       __func__, serio->name);
-		return;
-	}
 	serio_init_port(serio);
 	serio_queue_event(serio, owner, SERIO_REGISTER_PORT);
 }
diff --git a/include/linux/serio.h b/include/linux/serio.h
index 075f1b8d76faf94aa9e7d69b0d31b2b6dd4416cd..6c27d413da921dadcdbad2c0d60f34a654f36c98 100644
--- a/include/linux/serio.h
+++ b/include/linux/serio.h
@@ -121,7 +121,10 @@ void serio_unregister_driver(struct serio_driver *drv);
 
 static inline int serio_write(struct serio *serio, unsigned char data)
 {
-	return serio->write(serio, data);
+	if (serio->write)
+		return serio->write(serio, data);
+	else
+		return -1;
 }
 
 static inline void serio_drv_write_wakeup(struct serio *serio)