v4.19.13 snapshot.
diff --git a/drivers/media/rc/rc-loopback.c b/drivers/media/rc/rc-loopback.c
new file mode 100644
index 0000000..3822d9e
--- /dev/null
+++ b/drivers/media/rc/rc-loopback.c
@@ -0,0 +1,280 @@
+/*
+ * Loopback driver for rc-core,
+ *
+ * Copyright (c) 2010 David Härdeman <david@hardeman.nu>
+ *
+ * This driver receives TX data and passes it back as RX data,
+ * which is useful for (scripted) debugging of rc-core without
+ * having to use actual hardware.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <media/rc-core.h>
+
+#define DRIVER_NAME	"rc-loopback"
+#define dprintk(x...)	if (debug) printk(KERN_INFO DRIVER_NAME ": " x)
+#define RXMASK_REGULAR	0x1
+#define RXMASK_LEARNING	0x2
+
+static bool debug;
+
+struct loopback_dev {
+	struct rc_dev *dev;
+	u32 txmask;
+	u32 txcarrier;
+	u32 txduty;
+	bool idle;
+	bool learning;
+	bool carrierreport;
+	u32 rxcarriermin;
+	u32 rxcarriermax;
+};
+
+static struct loopback_dev loopdev;
+
+static int loop_set_tx_mask(struct rc_dev *dev, u32 mask)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	if ((mask & (RXMASK_REGULAR | RXMASK_LEARNING)) != mask) {
+		dprintk("invalid tx mask: %u\n", mask);
+		return -EINVAL;
+	}
+
+	dprintk("setting tx mask: %u\n", mask);
+	lodev->txmask = mask;
+	return 0;
+}
+
+static int loop_set_tx_carrier(struct rc_dev *dev, u32 carrier)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	dprintk("setting tx carrier: %u\n", carrier);
+	lodev->txcarrier = carrier;
+	return 0;
+}
+
+static int loop_set_tx_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	if (duty_cycle < 1 || duty_cycle > 99) {
+		dprintk("invalid duty cycle: %u\n", duty_cycle);
+		return -EINVAL;
+	}
+
+	dprintk("setting duty cycle: %u\n", duty_cycle);
+	lodev->txduty = duty_cycle;
+	return 0;
+}
+
+static int loop_set_rx_carrier_range(struct rc_dev *dev, u32 min, u32 max)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	if (min < 1 || min > max) {
+		dprintk("invalid rx carrier range %u to %u\n", min, max);
+		return -EINVAL;
+	}
+
+	dprintk("setting rx carrier range %u to %u\n", min, max);
+	lodev->rxcarriermin = min;
+	lodev->rxcarriermax = max;
+	return 0;
+}
+
+static int loop_tx_ir(struct rc_dev *dev, unsigned *txbuf, unsigned count)
+{
+	struct loopback_dev *lodev = dev->priv;
+	u32 rxmask;
+	unsigned i;
+	DEFINE_IR_RAW_EVENT(rawir);
+
+	if (lodev->txcarrier < lodev->rxcarriermin ||
+	    lodev->txcarrier > lodev->rxcarriermax) {
+		dprintk("ignoring tx, carrier out of range\n");
+		goto out;
+	}
+
+	if (lodev->learning)
+		rxmask = RXMASK_LEARNING;
+	else
+		rxmask = RXMASK_REGULAR;
+
+	if (!(rxmask & lodev->txmask)) {
+		dprintk("ignoring tx, rx mask mismatch\n");
+		goto out;
+	}
+
+	for (i = 0; i < count; i++) {
+		rawir.pulse = i % 2 ? false : true;
+		rawir.duration = txbuf[i] * 1000;
+		if (rawir.duration)
+			ir_raw_event_store_with_filter(dev, &rawir);
+	}
+
+	/* Fake a silence long enough to cause us to go idle */
+	rawir.pulse = false;
+	rawir.duration = dev->timeout;
+	ir_raw_event_store_with_filter(dev, &rawir);
+
+	ir_raw_event_handle(dev);
+
+out:
+	return count;
+}
+
+static void loop_set_idle(struct rc_dev *dev, bool enable)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	if (lodev->idle != enable) {
+		dprintk("%sing idle mode\n", enable ? "enter" : "exit");
+		lodev->idle = enable;
+	}
+}
+
+static int loop_set_learning_mode(struct rc_dev *dev, int enable)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	if (lodev->learning != enable) {
+		dprintk("%sing learning mode\n", enable ? "enter" : "exit");
+		lodev->learning = !!enable;
+	}
+
+	return 0;
+}
+
+static int loop_set_carrier_report(struct rc_dev *dev, int enable)
+{
+	struct loopback_dev *lodev = dev->priv;
+
+	if (lodev->carrierreport != enable) {
+		dprintk("%sabling carrier reports\n", enable ? "en" : "dis");
+		lodev->carrierreport = !!enable;
+	}
+
+	return 0;
+}
+
+static int loop_set_wakeup_filter(struct rc_dev *dev,
+				  struct rc_scancode_filter *sc)
+{
+	static const unsigned int max = 512;
+	struct ir_raw_event *raw;
+	int ret;
+	int i;
+
+	/* fine to disable filter */
+	if (!sc->mask)
+		return 0;
+
+	/* encode the specified filter and loop it back */
+	raw = kmalloc_array(max, sizeof(*raw), GFP_KERNEL);
+	if (!raw)
+		return -ENOMEM;
+
+	ret = ir_raw_encode_scancode(dev->wakeup_protocol, sc->data, raw, max);
+	/* still loop back the partial raw IR even if it's incomplete */
+	if (ret == -ENOBUFS)
+		ret = max;
+	if (ret >= 0) {
+		/* do the loopback */
+		for (i = 0; i < ret; ++i)
+			ir_raw_event_store(dev, &raw[i]);
+		ir_raw_event_handle(dev);
+
+		ret = 0;
+	}
+
+	kfree(raw);
+
+	return ret;
+}
+
+static int __init loop_init(void)
+{
+	struct rc_dev *rc;
+	int ret;
+
+	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
+	if (!rc) {
+		printk(KERN_ERR DRIVER_NAME ": rc_dev allocation failed\n");
+		return -ENOMEM;
+	}
+
+	rc->device_name		= "rc-core loopback device";
+	rc->input_phys		= "rc-core/virtual";
+	rc->input_id.bustype	= BUS_VIRTUAL;
+	rc->input_id.version	= 1;
+	rc->driver_name		= DRIVER_NAME;
+	rc->map_name		= RC_MAP_EMPTY;
+	rc->priv		= &loopdev;
+	rc->allowed_protocols	= RC_PROTO_BIT_ALL_IR_DECODER;
+	rc->allowed_wakeup_protocols = RC_PROTO_BIT_ALL_IR_ENCODER;
+	rc->encode_wakeup	= true;
+	rc->timeout		= 100 * 1000 * 1000; /* 100 ms */
+	rc->min_timeout		= 1;
+	rc->max_timeout		= UINT_MAX;
+	rc->rx_resolution	= 1000;
+	rc->tx_resolution	= 1000;
+	rc->s_tx_mask		= loop_set_tx_mask;
+	rc->s_tx_carrier	= loop_set_tx_carrier;
+	rc->s_tx_duty_cycle	= loop_set_tx_duty_cycle;
+	rc->s_rx_carrier_range	= loop_set_rx_carrier_range;
+	rc->tx_ir		= loop_tx_ir;
+	rc->s_idle		= loop_set_idle;
+	rc->s_learning_mode	= loop_set_learning_mode;
+	rc->s_carrier_report	= loop_set_carrier_report;
+	rc->s_wakeup_filter	= loop_set_wakeup_filter;
+
+	loopdev.txmask		= RXMASK_REGULAR;
+	loopdev.txcarrier	= 36000;
+	loopdev.txduty		= 50;
+	loopdev.rxcarriermin	= 1;
+	loopdev.rxcarriermax	= ~0;
+	loopdev.idle		= true;
+	loopdev.learning	= false;
+	loopdev.carrierreport	= false;
+
+	ret = rc_register_device(rc);
+	if (ret < 0) {
+		printk(KERN_ERR DRIVER_NAME ": rc_dev registration failed\n");
+		rc_free_device(rc);
+		return ret;
+	}
+
+	loopdev.dev = rc;
+	return 0;
+}
+
+static void __exit loop_exit(void)
+{
+	rc_unregister_device(loopdev.dev);
+}
+
+module_init(loop_init);
+module_exit(loop_exit);
+
+module_param(debug, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Enable debug messages");
+
+MODULE_DESCRIPTION("Loopback device for rc-core debugging");
+MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
+MODULE_LICENSE("GPL");