V4L/DVB: ir-core: move decoding state to ir_raw_event_ctrl

This patch moves the state from each raw decoder into the
ir_raw_event_ctrl struct.

This allows the removal of code like this:

        spin_lock(&decoder_lock);
        list_for_each_entry(data, &decoder_list, list) {
                if (data->ir_dev == ir_dev)
                        break;
        }
        spin_unlock(&decoder_lock);
        return data;

which is currently run for each decoder on each event in order
to get the client-specific decoding state data.

In addition, ir decoding modules and ir driver module load
order is now independent. Centralizing the data also allows
for a nice code reduction of about 30% per raw decoder as
client lists and client registration callbacks are no longer
necessary (but still kept around for the benefit of the lirc
decoder).

Out-of-tree modules can still use a similar trick to what
the raw decoders did before this patch until they are merged.

Signed-off-by: David Härdeman <david@hardeman.nu>
Acked-by: Jarod Wilson <jarod@redhat.com>
Tested-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/IR/ir-rc6-decoder.c b/drivers/media/IR/ir-rc6-decoder.c
index 2ebd4ea..f1624b8 100644
--- a/drivers/media/IR/ir-rc6-decoder.c
+++ b/drivers/media/IR/ir-rc6-decoder.c
@@ -36,10 +36,6 @@
 #define RC6_STARTBIT_MASK	0x08	/* for the header bits */
 #define RC6_6A_MCE_TOGGLE_MASK	0x8000	/* for the body bits */
 
-/* Used to register rc6_decoder clients */
-static LIST_HEAD(decoder_list);
-static DEFINE_SPINLOCK(decoder_lock);
-
 enum rc6_mode {
 	RC6_MODE_0,
 	RC6_MODE_6A,
@@ -58,41 +54,8 @@
 	STATE_FINISHED,
 };
 
-struct decoder_data {
-	struct list_head	list;
-	struct ir_input_dev	*ir_dev;
-
-	/* State machine control */
-	enum rc6_state		state;
-	u8			header;
-	u32			body;
-	struct ir_raw_event	prev_ev;
-	bool			toggle;
-	unsigned		count;
-	unsigned		wanted_bits;
-};
-
-
-/**
- * get_decoder_data()	- gets decoder data
- * @input_dev:	input device
- *
- * Returns the struct decoder_data that corresponds to a device
- */
-static struct decoder_data *get_decoder_data(struct  ir_input_dev *ir_dev)
+static enum rc6_mode rc6_mode(struct rc6_dec *data)
 {
-	struct decoder_data *data = NULL;
-
-	spin_lock(&decoder_lock);
-	list_for_each_entry(data, &decoder_list, list) {
-		if (data->ir_dev == ir_dev)
-			break;
-	}
-	spin_unlock(&decoder_lock);
-	return data;
-}
-
-static enum rc6_mode rc6_mode(struct decoder_data *data) {
 	switch (data->header & RC6_MODE_MASK) {
 	case 0:
 		return RC6_MODE_0;
@@ -114,15 +77,11 @@
  */
 static int ir_rc6_decode(struct input_dev *input_dev, struct ir_raw_event ev)
 {
-	struct decoder_data *data;
 	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+	struct rc6_dec *data = &ir_dev->raw->rc6;
 	u32 scancode;
 	u8 toggle;
 
-	data = get_decoder_data(ir_dev);
-	if (!data)
-		return -EINVAL;
-
 	if (!(ir_dev->raw->enabled_protocols & IR_TYPE_RC6))
 		return 0;
 
@@ -175,12 +134,11 @@
 		if (ev.pulse)
 			data->header |= 1;
 		data->count++;
-		data->prev_ev = ev;
 		data->state = STATE_HEADER_BIT_END;
 		return 0;
 
 	case STATE_HEADER_BIT_END:
-		if (!is_transition(&ev, &data->prev_ev))
+		if (!is_transition(&ev, &ir_dev->raw->prev_ev))
 			break;
 
 		if (data->count == RC6_HEADER_NBITS)
@@ -196,12 +154,11 @@
 			break;
 
 		data->toggle = ev.pulse;
-		data->prev_ev = ev;
 		data->state = STATE_TOGGLE_END;
 		return 0;
 
 	case STATE_TOGGLE_END:
-		if (!is_transition(&ev, &data->prev_ev) ||
+		if (!is_transition(&ev, &ir_dev->raw->prev_ev) ||
 		    !geq_margin(ev.duration, RC6_TOGGLE_END, RC6_UNIT / 2))
 			break;
 
@@ -211,7 +168,6 @@
 		}
 
 		data->state = STATE_BODY_BIT_START;
-		data->prev_ev = ev;
 		decrease_duration(&ev, RC6_TOGGLE_END);
 		data->count = 0;
 
@@ -243,13 +199,11 @@
 		if (ev.pulse)
 			data->body |= 1;
 		data->count++;
-		data->prev_ev = ev;
-
 		data->state = STATE_BODY_BIT_END;
 		return 0;
 
 	case STATE_BODY_BIT_END:
-		if (!is_transition(&ev, &data->prev_ev))
+		if (!is_transition(&ev, &ir_dev->raw->prev_ev))
 			break;
 
 		if (data->count == data->wanted_bits)
@@ -300,45 +254,9 @@
 	return -EINVAL;
 }
 
-static int ir_rc6_register(struct input_dev *input_dev)
-{
-	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
-	struct decoder_data *data;
-
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	data->ir_dev = ir_dev;
-
-	spin_lock(&decoder_lock);
-	list_add_tail(&data->list, &decoder_list);
-	spin_unlock(&decoder_lock);
-
-	return 0;
-}
-
-static int ir_rc6_unregister(struct input_dev *input_dev)
-{
-	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
-	static struct decoder_data *data;
-
-	data = get_decoder_data(ir_dev);
-	if (!data)
-		return 0;
-
-	spin_lock(&decoder_lock);
-	list_del(&data->list);
-	spin_unlock(&decoder_lock);
-
-	return 0;
-}
-
 static struct ir_raw_handler rc6_handler = {
 	.protocols	= IR_TYPE_RC6,
 	.decode		= ir_rc6_decode,
-	.raw_register	= ir_rc6_register,
-	.raw_unregister	= ir_rc6_unregister,
 };
 
 static int __init ir_rc6_decode_init(void)