macintosh/via-pmu: Clean up interrupt statistics

Replace an open-coded ffs() with the function call.
Simplify an if-else cascade using a switch statement.
Correct a typo and an indentation issue.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

drivers/macintosh/via-pmu.c

@@ -1355,7 +1355,8 @@ pmu_resume(void)
 static void
 pmu_handle_data(unsigned char *data, int len)
 {
-	unsigned char ints, pirq;
+	unsigned char ints;
+	int idx;
 	int i = 0;
 
 	asleep = 0;
@@ -1377,25 +1378,24 @@ pmu_handle_data(unsigned char *data, int len)
 		ints &= ~(PMU_INT_ADB_AUTO | PMU_INT_AUTO_SRQ_POLL);
 
 next:
-
 	if (ints == 0) {
 		if (i > pmu_irq_stats[10])
 			pmu_irq_stats[10] = i;
 		return;
 	}
-
-	for (pirq = 0; pirq < 8; pirq++)
-		if (ints & (1 << pirq))
-			break;
-	pmu_irq_stats[pirq]++;
 	i++;
-	ints &= ~(1 << pirq);
+
+	idx = ffs(ints) - 1;
+	ints &= ~BIT(idx);
+
+	pmu_irq_stats[idx]++;
 
 	/* Note: for some reason, we get an interrupt with len=1,
 	 * data[0]==0 after each normal ADB interrupt, at least
 	 * on the Pismo. Still investigating...  --BenH
 	 */
-	if ((1 << pirq) & PMU_INT_ADB) {
+	switch (BIT(idx)) {
+	case PMU_INT_ADB:
 		if ((data[0] & PMU_INT_ADB_AUTO) == 0) {
 			struct adb_request *req = req_awaiting_reply;
 			if (!req) {
@@ -1433,25 +1433,28 @@ next:
 				adb_input(data+1, len-1, 1);
 #endif /* CONFIG_ADB */		
 		}
-	}
+		break;
+
 	/* Sound/brightness button pressed */
-	else if ((1 << pirq) & PMU_INT_SNDBRT) {
+	case PMU_INT_SNDBRT:
 #ifdef CONFIG_PMAC_BACKLIGHT
 		if (len == 3)
 			pmac_backlight_set_legacy_brightness_pmu(data[1] >> 4);
 #endif
-	}
+		break;
+
 	/* Tick interrupt */
-	else if ((1 << pirq) & PMU_INT_TICK) {
-		/* Environement or tick interrupt, query batteries */
+	case PMU_INT_TICK:
+		/* Environment or tick interrupt, query batteries */
 		if (pmu_battery_count) {
 			if ((--query_batt_timer) == 0) {
 				query_battery_state();
 				query_batt_timer = BATTERY_POLLING_COUNT;
 			}
 		}
-        }
-	else if ((1 << pirq) & PMU_INT_ENVIRONMENT) {
+		break;
+
+	case PMU_INT_ENVIRONMENT:
 		if (pmu_battery_count)
 			query_battery_state();
 		pmu_pass_intr(data, len);
@@ -1461,7 +1464,9 @@ next:
 			via_pmu_event(PMU_EVT_POWER, !!(data[1]&8));
 			via_pmu_event(PMU_EVT_LID, data[1]&1);
 		}
-	} else {
+		break;
+
+	default:
 	       pmu_pass_intr(data, len);
 	}
 	goto next;