net: hamradio: use time_is_after_jiffies() instead of open coding it

Use the helper function time_is_{before,after}_jiffies() to improve
code readability.
Signed-off-by: NWang Qing <wangqing@vivo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/hamradio/dmascc.c

@@ -28,6 +28,7 @@
 #include <asm/io.h>
 #include <asm/irq.h>
 #include <linux/uaccess.h>
+#include <linux/jiffies.h>
 #include <net/ax25.h>
 #include "z8530.h"
 
@@ -377,7 +378,7 @@ static int __init dmascc_init(void)
 		udelay(2000000 / TMR_0_HZ);
 
 		/* Timing loop */
-		while (jiffies - time < 13) {
+		while (time_is_after_jiffies(time + 13)) {
 			for (i = 0; i < hw[h].num_devs; i++)
 				if (base[i] && counting[i]) {
 					/* Read back Timer 1: latch; read LSB; read MSB */
@@ -525,7 +526,7 @@ static int __init setup_adapter(int card_base, int type, int n)
 
 	/* Wait and detect IRQ */
 	time = jiffies;
-	while (jiffies - time < 2 + HZ / TMR_0_HZ);
+	while (time_is_after_jiffies(time + 2 + HZ / TMR_0_HZ));
 	irq = probe_irq_off(irqs);
 
 	/* Clear pending interrupt, disable interrupts */
@@ -1353,7 +1354,7 @@ static void es_isr(struct scc_priv *priv)
 		/* Switch state */
 		write_scc(priv, R15, 0);
 		if (priv->tx_count &&
-		    (jiffies - priv->tx_start) < priv->param.txtimeout) {
+		    time_is_after_jiffies(priv->tx_start + priv->param.txtimeout) {
 			priv->state = TX_PAUSE;
 			start_timer(priv, priv->param.txpause, 0);
 		} else {