[media] rc: rc-core: Add support for encode_wakeup drivers

Add support in rc-core for drivers which implement the wakeup scancode
filter by encoding the scancode using the raw IR encoders. This is by
way of rc_dev::encode_wakeup which should be set to true to make the
allowed wakeup protocols the same as the set of raw IR encoders.

As well as updating the sysfs interface to know which wakeup protocols
are allowed for encode_wakeup drivers, also ensure that the IR
decoders/encoders are loaded when an encode_wakeup driver is registered.

Signed-off-by: James Hogan <[e-mail]>
Signed-off-by: Antti Seppälä <[e-mail]>
Cc: David Härdeman <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/rc/rc-core-priv.h

···
  * Routines from rc-raw.c to be used internally and by decoders
  */
 u64 ir_raw_get_allowed_protocols(void);
+u64 ir_raw_get_encode_protocols(void);
 int ir_raw_event_register(struct rc_dev *dev);
 void ir_raw_event_unregister(struct rc_dev *dev);
 int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler);

drivers/media/rc/rc-ir-raw.c

···
 static DEFINE_MUTEX(ir_raw_handler_lock);
 static LIST_HEAD(ir_raw_handler_list);
 static u64 available_protocols;
+static u64 encode_protocols;
 
 static int ir_raw_event_thread(void *data)
 {
···
 	u64 protocols;
 	mutex_lock(&ir_raw_handler_lock);
 	protocols = available_protocols;
+	mutex_unlock(&ir_raw_handler_lock);
+	return protocols;
+}
+
+/* used internally by the sysfs interface */
+u64
+ir_raw_get_encode_protocols(void)
+{
+	u64 protocols;
+
+	mutex_lock(&ir_raw_handler_lock);
+	protocols = encode_protocols;
 	mutex_unlock(&ir_raw_handler_lock);
 	return protocols;
 }
···
 		list_for_each_entry(raw, &ir_raw_client_list, list)
 			ir_raw_handler->raw_register(raw->dev);
 	available_protocols |= ir_raw_handler->protocols;
+	if (ir_raw_handler->encode)
+		encode_protocols |= ir_raw_handler->protocols;
 	mutex_unlock(&ir_raw_handler_lock);
 
 	return 0;
···
 		list_for_each_entry(raw, &ir_raw_client_list, list)
 			ir_raw_handler->raw_unregister(raw->dev);
 	available_protocols &= ~ir_raw_handler->protocols;
+	if (ir_raw_handler->encode)
+		encode_protocols &= ~ir_raw_handler->protocols;
 	mutex_unlock(&ir_raw_handler_lock);
 }
 EXPORT_SYMBOL(ir_raw_handler_unregister);

drivers/media/rc/rc-main.c

···
 	} else {
 		enabled = dev->enabled_wakeup_protocols;
 		allowed = dev->allowed_wakeup_protocols;
+		if (dev->encode_wakeup && !allowed)
+			allowed = ir_raw_get_encode_protocols();
 	}
 
 	mutex_unlock(&dev->lock);
···
 		path ? path : "N/A");
 	kfree(path);
 
-	if (dev->driver_type == RC_DRIVER_IR_RAW) {
+	if (dev->driver_type == RC_DRIVER_IR_RAW || dev->encode_wakeup) {
 		/* Load raw decoders, if they aren't already */
 		if (!raw_init) {
 			IR_dprintk(1, "Loading raw decoders\n");
 			ir_raw_init();
 			raw_init = true;
 		}
+	}
+
+	if (dev->driver_type == RC_DRIVER_IR_RAW) {
 		/* calls ir_register_device so unlock mutex here*/
 		mutex_unlock(&dev->lock);
 		rc = ir_raw_event_register(dev);

include/media/rc-core.h

···
  * @input_dev: the input child device used to communicate events to userspace
  * @driver_type: specifies if protocol decoding is done in hardware or software
  * @idle: used to keep track of RX state
+ * @encode_wakeup: wakeup filtering uses IR encode API, therefore the allowed
+ *	wakeup protocols is the set of all raw encoders
  * @allowed_protocols: bitmask with the supported RC_BIT_* protocols
  * @enabled_protocols: bitmask with the enabled RC_BIT_* protocols
  * @allowed_wakeup_protocols: bitmask with the supported RC_BIT_* wakeup protocols
···
 	struct input_dev		*input_dev;
 	enum rc_driver_type		driver_type;
 	bool				idle;
+	bool				encode_wakeup;
 	u64				allowed_protocols;
 	u64				enabled_protocols;
 	u64				allowed_wakeup_protocols;