diff --git a/drivers/delay_timer/delay_timer.c b/drivers/delay_timer/delay_timer.c
index 587724e..feac357 100644
--- a/drivers/delay_timer/delay_timer.c
+++ b/drivers/delay_timer/delay_timer.c
@@ -20,20 +20,21 @@
  ***********************************************************/
 void udelay(uint32_t usec)
 {
-	assert(timer_ops != NULL &&
-		(timer_ops->clk_mult != 0) &&
-		(timer_ops->clk_div != 0) &&
+	assert((timer_ops != NULL) &&
+		(timer_ops->clk_mult != 0U) &&
+		(timer_ops->clk_div != 0U) &&
 		(timer_ops->get_timer_value != NULL));
 
 	uint32_t start, delta, total_delta;
 
-	assert(usec < UINT32_MAX / timer_ops->clk_div);
+	assert(usec < (UINT32_MAX / timer_ops->clk_div));
 
 	start = timer_ops->get_timer_value();
 
 	/* Add an extra tick to avoid delaying less than requested. */
 	total_delta =
-		div_round_up(usec * timer_ops->clk_div, timer_ops->clk_mult) + 1;
+		div_round_up(usec * timer_ops->clk_div,
+						timer_ops->clk_mult) + 1U;
 
 	do {
 		/*
@@ -51,7 +52,7 @@
  ***********************************************************/
 void mdelay(uint32_t msec)
 {
-	udelay(msec*1000);
+	udelay(msec * 1000U);
 }
 
 /***********************************************************
@@ -60,9 +61,9 @@
  ***********************************************************/
 void timer_init(const timer_ops_t *ops_ptr)
 {
-	assert(ops_ptr != NULL  &&
-		(ops_ptr->clk_mult != 0) &&
-		(ops_ptr->clk_div != 0) &&
+	assert((ops_ptr != NULL)  &&
+		(ops_ptr->clk_mult != 0U) &&
+		(ops_ptr->clk_div != 0U) &&
 		(ops_ptr->get_timer_value != NULL));
 
 	timer_ops = ops_ptr;
diff --git a/drivers/delay_timer/generic_delay_timer.c b/drivers/delay_timer/generic_delay_timer.c
index 8a36c8a..03ca532 100644
--- a/drivers/delay_timer/generic_delay_timer.c
+++ b/drivers/delay_timer/generic_delay_timer.c
@@ -49,9 +49,9 @@
 	unsigned int div  = plat_get_syscnt_freq2();
 
 	/* Reduce multiplier and divider by dividing them repeatedly by 10 */
-	while ((mult % 10 == 0) && (div % 10 == 0)) {
-		mult /= 10;
-		div /= 10;
+	while (((mult % 10U) == 0U) && ((div % 10U) == 0U)) {
+		mult /= 10U;
+		div /= 10U;
 	}
 
 	generic_delay_timer_init_args(mult, div);
diff --git a/include/lib/utils_def.h b/include/lib/utils_def.h
index 5b4fd78..1dd57cb 100644
--- a/include/lib/utils_def.h
+++ b/include/lib/utils_def.h
@@ -50,7 +50,7 @@
 
 #define div_round_up(val, div) __extension__ ({	\
 	__typeof__(div) _div = (div);		\
-	((val) + _div - 1) / _div;		\
+	((val) + _div - (__typeof__(div)) 1) / _div;		\
 })
 
 #define MIN(x, y) __extension__ ({	\