[media] rc-core: remove generic scancode filter

The generic scancode filtering has questionable value and makes it
impossible to determine from userspace if there is an actual
scancode hw filter present or not.

So revert the generic parts.

Based on a patch from James Hogan <james.hogan@imgtec.com>, but this
version also makes sure that only the valid sysfs files are created
in the first place.

Signed-off-by: David Härdeman <david@hardeman.nu>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/rc/rc-main.c

@@ -633,19 +633,13 @@ EXPORT_SYMBOL_GPL(rc_repeat);
 static void ir_do_keydown(struct rc_dev *dev, int scancode,
 			  u32 keycode, u8 toggle)
 {
-	struct rc_scancode_filter *filter;
-	bool new_event = !dev->keypressed ||
-			 dev->last_scancode != scancode ||
-			 dev->last_toggle != toggle;
+	bool new_event = (!dev->keypressed		 ||
+			  dev->last_scancode != scancode ||
+			  dev->last_toggle != toggle);
 
 	if (new_event && dev->keypressed)
 		ir_do_keyup(dev, false);
 
-	/* Generic scancode filtering */
-	filter = &dev->scancode_filters[RC_FILTER_NORMAL];
-	if (filter->mask && ((scancode ^ filter->data) & filter->mask))
-		return;
-
 	input_event(dev->input_dev, EV_MSC, MSC_SCAN, scancode);
 
 	if (new_event && keycode != KEY_RESERVED) {
@@ -1011,14 +1005,11 @@ static ssize_t store_protocols(struct device *device,
 	set_filter = (fattr->type == RC_FILTER_NORMAL)
 		? dev->s_filter : dev->s_wakeup_filter;
 
-	if (old_type != type && filter->mask) {
+	if (set_filter && old_type != type && filter->mask) {
 		local_filter = *filter;
 		if (!type) {
 			/* no protocol => clear filter */
 			ret = -1;
-		} else if (!set_filter) {
-			/* generic filtering => accept any filter */
-			ret = 0;
 		} else {
 			/* hardware filtering => try setting, otherwise clear */
 			ret = set_filter(dev, &local_filter);
@@ -1027,8 +1018,7 @@ static ssize_t store_protocols(struct device *device,
 			/* clear the filter */
 			local_filter.data = 0;
 			local_filter.mask = 0;
-			if (set_filter)
-				set_filter(dev, &local_filter);
+			set_filter(dev, &local_filter);
 		}
 
 		/* commit the new filter */
@@ -1072,7 +1062,10 @@ static ssize_t show_filter(struct device *device,
 		return -EINVAL;
 
 	mutex_lock(&dev->lock);
-	if (fattr->mask)
+	if ((fattr->type == RC_FILTER_NORMAL && !dev->s_filter) ||
+	    (fattr->type == RC_FILTER_WAKEUP && !dev->s_wakeup_filter))
+		val = 0;
+	else if (fattr->mask)
 		val = dev->scancode_filters[fattr->type].mask;
 	else
 		val = dev->scancode_filters[fattr->type].data;
@@ -1120,12 +1113,11 @@ static ssize_t store_filter(struct device *device,
 	if (ret < 0)
 		return ret;
 
+	/* Can the scancode filter be set? */
 	set_filter = (fattr->type == RC_FILTER_NORMAL) ? dev->s_filter :
 							 dev->s_wakeup_filter;
-
-	/* Scancode filter not supported (but still accept 0) */
-	if (!set_filter && fattr->type == RC_FILTER_WAKEUP)
-		return val ? -EINVAL : count;
+	if (!set_filter)
+		return -EINVAL;
 
 	mutex_lock(&dev->lock);
 
@@ -1143,11 +1135,9 @@ static ssize_t store_filter(struct device *device,
 		goto unlock;
 	}
 
-	if (set_filter) {
-		ret = set_filter(dev, &local_filter);
-		if (ret < 0)
-			goto unlock;
-	}
+	ret = set_filter(dev, &local_filter);
+	if (ret < 0)
+		goto unlock;
 
 	/* Success, commit the new filter */
 	*filter = local_filter;
@@ -1199,27 +1189,45 @@ static RC_FILTER_ATTR(wakeup_filter, S_IRUGO|S_IWUSR,
 static RC_FILTER_ATTR(wakeup_filter_mask, S_IRUGO|S_IWUSR,
 		      show_filter, store_filter, RC_FILTER_WAKEUP, true);
 
-static struct attribute *rc_dev_attrs[] = {
+static struct attribute *rc_dev_protocol_attrs[] = {
 	&dev_attr_protocols.attr.attr,
+	NULL,
+};
+
+static struct attribute_group rc_dev_protocol_attr_grp = {
+	.attrs	= rc_dev_protocol_attrs,
+};
+
+static struct attribute *rc_dev_wakeup_protocol_attrs[] = {
 	&dev_attr_wakeup_protocols.attr.attr,
+	NULL,
+};
+
+static struct attribute_group rc_dev_wakeup_protocol_attr_grp = {
+	.attrs	= rc_dev_wakeup_protocol_attrs,
+};
+
+static struct attribute *rc_dev_filter_attrs[] = {
 	&dev_attr_filter.attr.attr,
 	&dev_attr_filter_mask.attr.attr,
-	&dev_attr_wakeup_filter.attr.attr,
-	&dev_attr_wakeup_filter_mask.attr.attr,
 	NULL,
 };
 
-static struct attribute_group rc_dev_attr_grp = {
-	.attrs	= rc_dev_attrs,
+static struct attribute_group rc_dev_filter_attr_grp = {
+	.attrs	= rc_dev_filter_attrs,
 };
 
-static const struct attribute_group *rc_dev_attr_groups[] = {
-	&rc_dev_attr_grp,
-	NULL
+static struct attribute *rc_dev_wakeup_filter_attrs[] = {
+	&dev_attr_wakeup_filter.attr.attr,
+	&dev_attr_wakeup_filter_mask.attr.attr,
+	NULL,
+};
+
+static struct attribute_group rc_dev_wakeup_filter_attr_grp = {
+	.attrs	= rc_dev_wakeup_filter_attrs,
 };
 
 static struct device_type rc_dev_type = {
-	.groups		= rc_dev_attr_groups,
 	.release	= rc_dev_release,
 	.uevent		= rc_dev_uevent,
 };
@@ -1276,7 +1284,7 @@ int rc_register_device(struct rc_dev *dev)
 	static bool raw_init = false; /* raw decoders loaded? */
 	struct rc_map *rc_map;
 	const char *path;
-	int rc, devno;
+	int rc, devno, attr = 0;
 
 	if (!dev || !dev->map_name)
 		return -EINVAL;
@@ -1304,6 +1312,16 @@ int rc_register_device(struct rc_dev *dev)
 			return -ENOMEM;
 	} while (test_and_set_bit(devno, ir_core_dev_number));
 
+	dev->dev.groups = dev->sysfs_groups;
+	dev->sysfs_groups[attr++] = &rc_dev_protocol_attr_grp;
+	if (dev->s_filter)
+		dev->sysfs_groups[attr++] = &rc_dev_filter_attr_grp;	
+	if (dev->s_wakeup_filter)
+		dev->sysfs_groups[attr++] = &rc_dev_wakeup_filter_attr_grp;
+	if (dev->change_wakeup_protocol)
+		dev->sysfs_groups[attr++] = &rc_dev_wakeup_protocol_attr_grp;
+	dev->sysfs_groups[attr++] = NULL;
+
 	/*
 	 * Take the lock here, as the device sysfs node will appear
 	 * when device_add() is called, which may trigger an ir-keytable udev

include/media/rc-core.h

@@ -60,6 +60,7 @@ enum rc_filter_type {
 /**
  * struct rc_dev - represents a remote control device
  * @dev: driver model's view of this device
+ * @sysfs_groups: sysfs attribute groups
  * @input_name: name of the input child device
  * @input_phys: physical path to the input child device
  * @input_id: id of the input child device (struct input_id)
@@ -117,6 +118,7 @@ enum rc_filter_type {
  */
 struct rc_dev {
 	struct device			dev;
+	const struct attribute_group	*sysfs_groups[5];
 	const char			*input_name;
 	const char			*input_phys;
 	struct input_id			input_id;