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>

1 files changed, 77 insertions, 58 deletions

diff --git a/drivers/usb/input/ati_remote.c b/drivers/usb/input/ati_remote.c
index 5a56f6c..3719fcb 100644
--- a/drivers/usb/input/ati_remote.c
+++ b/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;
@@ -417,6 +414,43 @@ static int ati_remote_event_lookup(int rem, unsigned char d1, unsigned char d2)
 }
 
 /*
+ *	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
  */
 static void ati_remote_input_report(struct urb *urb, struct pt_regs *regs)
@@ -494,63 +528,48 @@ 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];
-
-	input_regs(dev, regs);
-	switch (ati_remote_tbl[index].kind) {
-	case KIND_ACCEL:
-		input_event(dev, ati_remote_tbl[index].type,
-			ati_remote_tbl[index].code,
-			ati_remote_tbl[index].value * acc);
-		break;
-	case KIND_LU:
-		input_report_rel(dev, REL_X, -acc);
-		input_report_rel(dev, REL_Y, -acc);
-		break;
-	case KIND_RU:
-		input_report_rel(dev, REL_X, acc);
-		input_report_rel(dev, REL_Y, -acc);
-		break;
-	case KIND_LD:
-		input_report_rel(dev, REL_X, -acc);
-		input_report_rel(dev, REL_Y, acc);
-		break;
-	case KIND_RD:
-		input_report_rel(dev, REL_X, acc);
-		input_report_rel(dev, REL_Y, acc);
-		break;
-	default:
-		dev_dbg(&ati_remote->interface->dev, "ati_remote kind=%d\n",
-			ati_remote_tbl[index].kind);
-	}
-	input_sync(dev);
+		/*
+		 * 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.
+		 */
+		acc = ati_remote_compute_accel(ati_remote);
 
-	ati_remote->old_jiffies = jiffies;
-	ati_remote->old_data[0] = data[1];
-	ati_remote->old_data[1] = data[2];
+		input_regs(dev, regs);
+		switch (ati_remote_tbl[index].kind) {
+		case KIND_ACCEL:
+			input_event(dev, ati_remote_tbl[index].type,
+				ati_remote_tbl[index].code,
+				ati_remote_tbl[index].value * acc);
+			break;
+		case KIND_LU:
+			input_report_rel(dev, REL_X, -acc);
+			input_report_rel(dev, REL_Y, -acc);
+			break;
+		case KIND_RU:
+			input_report_rel(dev, REL_X, acc);
+			input_report_rel(dev, REL_Y, -acc);
+			break;
+		case KIND_LD:
+			input_report_rel(dev, REL_X, -acc);
+			input_report_rel(dev, REL_Y, acc);
+			break;
+		case KIND_RD:
+			input_report_rel(dev, REL_X, acc);
+			input_report_rel(dev, REL_Y, acc);
+			break;
+		default:
+			dev_dbg(&ati_remote->interface->dev, "ati_remote kind=%d\n",
+				ati_remote_tbl[index].kind);
+		}
+		input_sync(dev);
+
+		ati_remote->old_jiffies = jiffies;
+		ati_remote->old_data[0] = data[1];
+		ati_remote->old_data[1] = data[2];
+	}
 }
 
 /*