input: Exclude tasklet changes to i8042.c

Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>

drivers/input/serio/i8042.c

@@ -2,7 +2,6 @@
  *  i8042 keyboard and mouse controller driver for Linux
  *
  *  Copyright (c) 1999-2002 Vojtech Pavlik
- *  Copyright (c) 2004      Dmitry Torokhov
  */
 
 /*
@@ -75,14 +74,6 @@ struct i8042_values {
 	unsigned char *phys;
 };
 
-#define I8042_QUEUE_LEN		64
-struct {
-	unsigned char str[I8042_QUEUE_LEN];
-	unsigned char data[I8042_QUEUE_LEN];
-	unsigned int read_pos;
-	unsigned int write_pos;
-} i8042_buf;
-
 static struct serio i8042_kbd_port;
 static struct serio i8042_aux_port;
 static unsigned char i8042_initial_ctr;
@@ -91,7 +82,7 @@ static unsigned char i8042_mux_open;
 static unsigned char i8042_mux_present;
 static unsigned char i8042_sysdev_initialized;
 static struct pm_dev *i8042_pm_dev;
-static struct timer_list i8042_timer;
+struct timer_list i8042_timer;
 
 /*
  * Shared IRQ's require a device pointer, but this driver doesn't support
@@ -383,28 +374,31 @@ static char i8042_mux_short[4][16];
 static char i8042_mux_phys[4][32];
 
 /*
- * i8042_handle_data() is the most important function in this driver -
- * it processes data received by i8042_interrupt and sends it to the
- * upper layers.
+ * i8042_interrupt() is the most important function in this driver -
+ * it handles the interrupts from the i8042, and sends incoming bytes
+ * to the upper layers.
  */
 
-static void i8042_handle_data(unsigned long notused)
+static irqreturn_t i8042_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
+	unsigned long flags;
 	unsigned char str, data = 0;
 	unsigned int dfl;
+	int ret;
 
-	/*
-	 * No locking it required on i8042_buf as the tasklet is guaranteed
-	 * to be serialized and if write_pos changes while comparing it with
-	 * read_pos another run will be scheduled by i8042_interrupt.
-	 */
-	while (i8042_buf.read_pos != i8042_buf.write_pos) {
+	mod_timer(&i8042_timer, jiffies + I8042_POLL_PERIOD);
 
-		str = i8042_buf.str[i8042_buf.read_pos];
-		data = i8042_buf.data[i8042_buf.read_pos];
+	spin_lock_irqsave(&i8042_lock, flags);
+	str = i8042_read_status();
+	if (str & I8042_STR_OBF)
+		data = i8042_read_data();
+	spin_unlock_irqrestore(&i8042_lock, flags);
 
-		i8042_buf.read_pos++;
-		i8042_buf.read_pos %= I8042_QUEUE_LEN;
+	if (~str & I8042_STR_OBF) {
+		if (irq) dbg("Interrupt %d, without any data", irq);
+		ret = 0;
+		goto out;
+	}
 
 	dfl = ((str & I8042_STR_PARITY) ? SERIO_PARITY : 0) |
 	      ((str & I8042_STR_TIMEOUT) ? SERIO_TIMEOUT : 0);
@@ -425,67 +419,32 @@ static void i8042_handle_data(unsigned long notused)
 			dfl & SERIO_PARITY ? ", bad parity" : "",
 			dfl & SERIO_TIMEOUT ? ", timeout" : "");
 
-			serio_interrupt(i8042_mux_port + ((str >> 6) & 3), data, dfl, NULL);
-		} else {
+		serio_interrupt(i8042_mux_port + ((str >> 6) & 3), data, dfl, regs);
+
+		goto irq_ret;
+	}
 
 	dbg("%02x <- i8042 (interrupt, %s, %d%s%s)",
 		data, (str & I8042_STR_AUXDATA) ? "aux" : "kbd", irq,
 		dfl & SERIO_PARITY ? ", bad parity" : "",
 		dfl & SERIO_TIMEOUT ? ", timeout" : "");
 
-			if (i8042_aux_values.exists && (str & I8042_STR_AUXDATA))
-				serio_interrupt(&i8042_aux_port, data, dfl, NULL);
-			else if (i8042_kbd_values.exists)
-				serio_interrupt(&i8042_kbd_port, data, dfl, NULL);
+	if (i8042_aux_values.exists && (str & I8042_STR_AUXDATA)) {
+		serio_interrupt(&i8042_aux_port, data, dfl, regs);
+		goto irq_ret;
 	}
-	}
-}
 
-DECLARE_TASKLET(i8042_tasklet, i8042_handle_data, 0);
+	if (!i8042_kbd_values.exists)
+		goto irq_ret;
 
-/*
- * i8042_interrupt() handles the interrupts from i8042 and schedules
- * i8042_handle_data to process and pass received bytes to the upper
- * layers.
- */
+	serio_interrupt(&i8042_kbd_port, data, dfl, regs);
 
-static irqreturn_t i8042_interrupt(int irq, void *dev_id, struct pt_regs *regs)
-{
-	unsigned long flags;
-	unsigned char str;
-	unsigned int n_bytes = 0;
-
-	mod_timer(&i8042_timer, jiffies + I8042_POLL_PERIOD);
-
-	spin_lock_irqsave(&i8042_lock, flags);
-
-	while ((str = i8042_read_status()) & I8042_STR_OBF) {
-
-		n_bytes++;
-
-		i8042_buf.str[i8042_buf.write_pos] = str;
-		i8042_buf.data[i8042_buf.write_pos] = i8042_read_data();
-
-		i8042_buf.write_pos++;
-		i8042_buf.write_pos %= I8042_QUEUE_LEN;
-
-		if (unlikely(i8042_buf.write_pos == i8042_buf.read_pos))
-			printk(KERN_WARNING "i8042.c: ring buffer full\n");
-	}
-
-	spin_unlock_irqrestore(&i8042_lock, flags);
-
-	if (unlikely(n_bytes == 0)) {
-		if (irq) dbg("Interrupt %d, without any data", irq);
-		return IRQ_NONE;
-	}
-
-	tasklet_schedule(&i8042_tasklet);
-
-	return IRQ_HANDLED;
+irq_ret:
+	ret = 1;
+out:
+	return IRQ_RETVAL(ret);
 }
 
-
 /*
  * i8042_enable_mux_mode checks whether the controller has an active
  * multiplexor and puts the chip into Multiplexed (as opposed to
@@ -1058,9 +1017,7 @@ void __exit i8042_exit(void)
 	for (i = 0; i < 4; i++)
 		if (i8042_mux_values[i].exists)
 			serio_unregister_port(i8042_mux_port + i);
-
 	del_timer_sync(&i8042_timer);
-	tasklet_kill(&i8042_tasklet);
 
 	i8042_platform_exit();
 }