Input: ALPS - force stream mode

ALPS appears to need SETSTREAM command after reset, otherwise it
does not produce any data. Now that we do not request stream mode
by default individual drivers need to take care of it.

[Jason Riedy <ejr@cs.berkeley.edu> - fix oops]
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/mouse/alps.c

@@ -251,11 +251,15 @@ static const struct alps_model_info *alps_get_model(struct psmouse *psmouse, int
 
 	dbg("E7 report: %2.2x %2.2x %2.2x", param[0], param[1], param[2]);
 
-	for (i = 0; i < ARRAY_SIZE(rates) && param[2] != rates[i]; i++);
-	*version = (param[0] << 8) | (param[1] << 4) | i;
+	if (version) {
+		for (i = 0; i < ARRAY_SIZE(rates) && param[2] != rates[i]; i++)
+			/* empty */;
+		*version = (param[0] << 8) | (param[1] << 4) | i;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(alps_model_data); i++)
-		if (!memcmp(param, alps_model_data[i].signature, sizeof(alps_model_data[i].signature)))
+		if (!memcmp(param, alps_model_data[i].signature,
+			    sizeof(alps_model_data[i].signature)))
 			return alps_model_data + i;
 
 	return NULL;
@@ -380,32 +384,46 @@ static int alps_poll(struct psmouse *psmouse)
 	return 0;
 }
 
-static int alps_reconnect(struct psmouse *psmouse)
+static int alps_hw_init(struct psmouse *psmouse, int *version)
 {
 	struct alps_data *priv = psmouse->private;
-	int version;
-
-	psmouse_reset(psmouse);
 
-	if (!(priv->i = alps_get_model(psmouse, &version)))
+	priv->i = alps_get_model(psmouse, version);
+	if (!priv->i)
 		return -1;
 
 	if ((priv->i->flags & ALPS_PASS) && alps_passthrough_mode(psmouse, 1))
 		return -1;
 
 	if (alps_tap_mode(psmouse, 1)) {
-		printk(KERN_WARNING "alps.c: Failed to reenable hardware tapping\n");
+		printk(KERN_WARNING "alps.c: Failed to enable hardware tapping\n");
 		return -1;
 	}
 
 	if (alps_absolute_mode(psmouse)) {
-		printk(KERN_ERR "alps.c: Failed to reenable absolute mode\n");
+		printk(KERN_ERR "alps.c: Failed to enable absolute mode\n");
 		return -1;
 	}
 
 	if ((priv->i->flags & ALPS_PASS) && alps_passthrough_mode(psmouse, 0))
 		return -1;
 
+	/* ALPS needs stream mode, otherwise it won't report any data */
+	if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSTREAM)) {
+		printk(KERN_ERR "alps.c: Failed to enable stream mode\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int alps_reconnect(struct psmouse *psmouse)
+{
+	psmouse_reset(psmouse);
+
+	if (alps_hw_init(psmouse, NULL))
+		return -1;
+
 	return 0;
 }
 
@@ -430,23 +448,9 @@ int alps_init(struct psmouse *psmouse)
 		goto init_fail;
 
 	priv->dev2 = dev2;
+	psmouse->private = priv;
 
-	priv->i = alps_get_model(psmouse, &version);
-	if (!priv->i)
-		goto init_fail;
-
-	if ((priv->i->flags & ALPS_PASS) && alps_passthrough_mode(psmouse, 1))
-		goto init_fail;
-
-	if (alps_tap_mode(psmouse, 1))
-		printk(KERN_WARNING "alps.c: Failed to enable hardware tapping\n");
-
-	if (alps_absolute_mode(psmouse)) {
-		printk(KERN_ERR "alps.c: Failed to enable absolute mode\n");
-		goto init_fail;
-	}
-
-	if ((priv->i->flags & ALPS_PASS) && alps_passthrough_mode(psmouse, 0))
+	if (alps_hw_init(psmouse, &version))
 		goto init_fail;
 
 	dev1->evbit[LONG(EV_KEY)] |= BIT(EV_KEY);
@@ -493,13 +497,13 @@ int alps_init(struct psmouse *psmouse)
 	/* We are having trouble resyncing ALPS touchpads so disable it for now */
 	psmouse->resync_time = 0;
 
-	psmouse->private = priv;
 	return 0;
 
 init_fail:
 	psmouse_reset(psmouse);
 	input_free_device(dev2);
 	kfree(priv);
+	psmouse->private = NULL;
 	return -1;
 }