Index: kernel/genarch/src/drivers/ns16550/ns16550.c
===================================================================
--- kernel/genarch/src/drivers/ns16550/ns16550.c	(revision 38b0ae2913b97fd6187fb83fbd73a39c7517ae23)
+++ kernel/genarch/src/drivers/ns16550/ns16550.c	(revision f5e5f73a339f61a91c3b3d97e7798f71f126023a)
@@ -47,9 +47,12 @@
 #define LSR_TH_READY    0x20
 
-static inline uint8_t _read(ns16550_instance_t *inst, int reg) {
+static uint8_t ns16550_reg_read(ns16550_instance_t *inst, ns16550_reg_t reg)
+{
 	return pio_read_8(&inst->ns16550[reg << inst->reg_shift]);
 }
 
-static inline void _write(ns16550_instance_t *inst, int reg, uint8_t val) {
+static void ns16550_reg_write(ns16550_instance_t *inst, ns16550_reg_t reg,
+    uint8_t val)
+{
 	pio_write_8(&inst->ns16550[reg << inst->reg_shift], val);
 }
@@ -59,5 +62,5 @@
 	ns16550_instance_t *instance = irq->instance;
 
-	if (_read(instance, NS16550_REG_LSR) & LSR_DATA_READY)
+	if (ns16550_reg_read(instance, NS16550_REG_LSR) & LSR_DATA_READY)
 		return IRQ_ACCEPT;
 	else
@@ -69,6 +72,6 @@
 	ns16550_instance_t *instance = irq->instance;
 	
-	while (_read(instance, NS16550_REG_LSR) & LSR_DATA_READY) {
-		uint8_t data = _read(instance, NS16550_REG_RBR);
+	while (ns16550_reg_read(instance, NS16550_REG_LSR) & LSR_DATA_READY) {
+		uint8_t data = ns16550_reg_read(instance, NS16550_REG_RBR);
 		indev_push_character(instance->input, data);
 	}
@@ -78,13 +81,13 @@
 static void ns16550_clear_buffer(ns16550_instance_t *instance)
 {
-	while (_read(instance, NS16550_REG_LSR) & LSR_DATA_READY)
-		(void) _read(instance, NS16550_REG_RBR);
+	while (ns16550_reg_read(instance, NS16550_REG_LSR) & LSR_DATA_READY)
+		(void) ns16550_reg_read(instance, NS16550_REG_RBR);
 }
 
 static void ns16550_sendb(ns16550_instance_t *instance, uint8_t byte)
 {
-	while (!(_read(instance, NS16550_REG_LSR) & LSR_TH_READY))
+	while (!(ns16550_reg_read(instance, NS16550_REG_LSR) & LSR_TH_READY))
 		;
-	_write(instance, NS16550_REG_THR, byte);
+	ns16550_reg_write(instance, NS16550_REG_THR, byte);
 }
 
@@ -122,5 +125,5 @@
  *
  */
-ns16550_instance_t *ns16550_init(ioport8_t *dev, int reg_shift, inr_t inr,
+ns16550_instance_t *ns16550_init(ioport8_t *dev, unsigned reg_shift, inr_t inr,
     cir_t cir, void *cir_arg, outdev_t **output)
 {
@@ -176,6 +179,6 @@
 	
 	/* Enable interrupts */
-	_write(instance, NS16550_REG_IER, IER_ERBFI);
-	_write(instance, NS16550_REG_MCR, MCR_OUT2);
+	ns16550_reg_write(instance, NS16550_REG_IER, IER_ERBFI);
+	ns16550_reg_write(instance, NS16550_REG_MCR, MCR_OUT2);
 }