Input: ati_remote - use msec instead of jiffies

By using milliseconds instead of jiffies to calculate acceleration
factor we make the code immune to changes in HZ.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/usb/input/ati_remote.c

@@ -157,9 +157,6 @@ MODULE_DEVICE_TABLE(usb, ati_remote_table);
 static char init1[] = { 0x01, 0x00, 0x20, 0x14 };
 static char init2[] = { 0x01, 0x00, 0x20, 0x14, 0x20, 0x20, 0x20 };
 
-/* Acceleration curve for directional control pad */
-static const char accel[] = { 1, 2, 4, 6, 9, 13, 20 };
-
 struct ati_remote {
 	struct input_dev *idev;
 	struct usb_device *udev;
@@ -416,6 +413,43 @@ static int ati_remote_event_lookup(int rem, unsigned char d1, unsigned char d2)
 	return -1;
 }
 
+/*
+ *	ati_remote_compute_accel
+ *
+ * Implements acceleration curve for directional control pad
+ * If elapsed time since last event is > 1/4 second, user "stopped",
+ * so reset acceleration. Otherwise, user is probably holding the control
+ * pad down, so we increase acceleration, ramping up over two seconds to
+ * a maximum speed.
+ */
+static int ati_remote_compute_accel(struct ati_remote *ati_remote)
+{
+	static const char accel[] = { 1, 2, 4, 6, 9, 13, 20 };
+	unsigned long now = jiffies;
+	int acc;
+
+	if (time_after(now, ati_remote->old_jiffies + msecs_to_jiffies(250))) {
+		acc = 1;
+		ati_remote->acc_jiffies = now;
+	}
+	else if (time_before(now, ati_remote->acc_jiffies + msecs_to_jiffies(125)))
+		acc = accel[0];
+	else if (time_before(now, ati_remote->acc_jiffies + msecs_to_jiffies(250)))
+		acc = accel[1];
+	else if (time_before(now, ati_remote->acc_jiffies + msecs_to_jiffies(500)))
+		acc = accel[2];
+	else if (time_before(now, ati_remote->acc_jiffies + msecs_to_jiffies(1000)))
+		acc = accel[3];
+	else if (time_before(now, ati_remote->acc_jiffies + msecs_to_jiffies(1500)))
+		acc = accel[4];
+	else if (time_before(now, ati_remote->acc_jiffies + msecs_to_jiffies(2000)))
+		acc = accel[5];
+	else
+		acc = accel[6];
+
+	return acc;
+}
+
 /*
  *	ati_remote_report_input
  */
@@ -494,30 +528,14 @@ static void ati_remote_input_report(struct urb *urb, struct pt_regs *regs)
 			ati_remote_tbl[index].code, 0);
 		input_sync(dev);
 
-		return;
-	}
+	} else {
 
 		/*
 		 * Other event kinds are from the directional control pad, and have an
 		 * acceleration factor applied to them.  Without this acceleration, the
 		 * control pad is mostly unusable.
-	 *
-	 * If elapsed time since last event is > 1/4 second, user "stopped",
-	 * so reset acceleration. Otherwise, user is probably holding the control
-	 * pad down, so we increase acceleration, ramping up over two seconds to
-	 * a maximum speed.  The acceleration curve is #defined above.
 		 */
-	if (time_after(jiffies, ati_remote->old_jiffies + (HZ >> 2))) {
-		acc = 1;
-		ati_remote->acc_jiffies = jiffies;
-	}
-	else if (time_before(jiffies, ati_remote->acc_jiffies + (HZ >> 3)))  acc = accel[0];
-	else if (time_before(jiffies, ati_remote->acc_jiffies + (HZ >> 2)))  acc = accel[1];
-	else if (time_before(jiffies, ati_remote->acc_jiffies + (HZ >> 1)))  acc = accel[2];
-	else if (time_before(jiffies, ati_remote->acc_jiffies + HZ))         acc = accel[3];
-	else if (time_before(jiffies, ati_remote->acc_jiffies + HZ+(HZ>>1))) acc = accel[4];
-	else if (time_before(jiffies, ati_remote->acc_jiffies + (HZ << 1)))  acc = accel[5];
-	else acc = accel[6];
+		acc = ati_remote_compute_accel(ati_remote);
 
 		input_regs(dev, regs);
 		switch (ati_remote_tbl[index].kind) {
@@ -551,6 +569,7 @@ static void ati_remote_input_report(struct urb *urb, struct pt_regs *regs)
 		ati_remote->old_jiffies = jiffies;
 		ati_remote->old_data[0] = data[1];
 		ati_remote->old_data[1] = data[2];
+	}
 }
 
 /*