media: rtl28xxu: fix idle handling

Currently the IR receiver is put into idle mode after each interrupt.
However longer IR like NEC can be distributed over multiple interrupts,
so putting the IR into idle in the middle of such a message will break
decoding.

Every IR message has a trailing space of 0xbf (one less than
IR_IDE_LEN{0,1} which is programmed to 0xc0). So, set the timeout to that
value and rc-core will put the IR receiver into idle mode automatically.

Thanks to Jan Pieter van Woerkom <jp@jpvw.nl> for providing the hardware.
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/usb/dvb-usb-v2/dvb_usb.h

@@ -121,6 +121,7 @@ struct dvb_usb_driver_info {
  * @interval: time in ms between two queries
  * @driver_type: used to point if a device supports raw mode
  * @bulk_mode: device supports bulk mode for rc (disable polling mode)
+ * @timeout: set to length of last space before raw IR goes idle
  */
 struct dvb_usb_rc {
 	const char *map_name;
@@ -130,6 +131,7 @@ struct dvb_usb_rc {
 	unsigned int interval;
 	enum rc_driver_type driver_type;
 	bool bulk_mode;
+	int timeout;
 };
 
 /**

drivers/media/usb/dvb-usb-v2/dvb_usb_core.c

@@ -150,6 +150,7 @@ static int dvb_usbv2_remote_init(struct dvb_usb_device *d)
 	dev->map_name = d->rc.map_name;
 	dev->allowed_protocols = d->rc.allowed_protos;
 	dev->change_protocol = d->rc.change_protocol;
+	dev->timeout = d->rc.timeout;
 	dev->priv = d;
 
 	ret = rc_register_device(dev);

drivers/media/usb/dvb-usb-v2/rtl28xxu.c

@@ -1781,7 +1781,6 @@ static int rtl2832u_rc_query(struct dvb_usb_device *d)
 	}
 
 	/* 'flush' ir_raw_event_store_with_filter() */
-	ir_raw_event_set_idle(d->rc_dev, true);
 	ir_raw_event_handle(d->rc_dev);
 exit:
 	return ret;
@@ -1804,6 +1803,8 @@ static int rtl2832u_get_rc_config(struct dvb_usb_device *d,
 	rc->driver_type = RC_DRIVER_IR_RAW;
 	rc->query = rtl2832u_rc_query;
 	rc->interval = 200;
+	/* we program idle len to 0xc0, set timeout to one less */
+	rc->timeout = 0xbf * 50800;
 
 	return 0;
 }