Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 296 insertions, 0 deletions

diff --git a/drivers/media/rc/ir-rc5-decoder.c b/drivers/media/rc/ir-rc5-decoder.c
new file mode 100644
index 000000000..63624654a
--- /dev/null
+++ b/drivers/media/rc/ir-rc5-decoder.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0
+// ir-rc5-decoder.c - decoder for RC5(x) and StreamZap protocols
+//
+// Copyright (C) 2010 by Mauro Carvalho Chehab
+// Copyright (C) 2010 by Jarod Wilson <jarod@redhat.com>
+
+/*
+ * This decoder handles the 14 bit RC5 protocol, 15 bit "StreamZap" protocol
+ * and 20 bit RC5x protocol.
+ */
+
+#include "rc-core-priv.h"
+#include <linux/module.h>
+
+#define RC5_NBITS		14
+#define RC5_SZ_NBITS		15
+#define RC5X_NBITS		20
+#define CHECK_RC5X_NBITS	8
+#define RC5_UNIT		888888 /* ns */
+#define RC5_BIT_START		(1 * RC5_UNIT)
+#define RC5_BIT_END		(1 * RC5_UNIT)
+#define RC5X_SPACE		(4 * RC5_UNIT)
+#define RC5_TRAILER		(6 * RC5_UNIT) /* In reality, approx 100 */
+
+enum rc5_state {
+	STATE_INACTIVE,
+	STATE_BIT_START,
+	STATE_BIT_END,
+	STATE_CHECK_RC5X,
+	STATE_FINISHED,
+};
+
+/**
+ * ir_rc5_decode() - Decode one RC-5 pulse or space
+ * @dev:	the struct rc_dev descriptor of the device
+ * @ev:		the struct ir_raw_event descriptor of the pulse/space
+ *
+ * This function returns -EINVAL if the pulse violates the state machine
+ */
+static int ir_rc5_decode(struct rc_dev *dev, struct ir_raw_event ev)
+{
+	struct rc5_dec *data = &dev->raw->rc5;
+	u8 toggle;
+	u32 scancode;
+	enum rc_proto protocol;
+
+	if (!is_timing_event(ev)) {
+		if (ev.reset)
+			data->state = STATE_INACTIVE;
+		return 0;
+	}
+
+	if (!geq_margin(ev.duration, RC5_UNIT, RC5_UNIT / 2))
+		goto out;
+
+again:
+	dev_dbg(&dev->dev, "RC5(x/sz) decode started at state %i (%uus %s)\n",
+		data->state, TO_US(ev.duration), TO_STR(ev.pulse));
+
+	if (!geq_margin(ev.duration, RC5_UNIT, RC5_UNIT / 2))
+		return 0;
+
+	switch (data->state) {
+
+	case STATE_INACTIVE:
+		if (!ev.pulse)
+			break;
+
+		data->state = STATE_BIT_START;
+		data->count = 1;
+		decrease_duration(&ev, RC5_BIT_START);
+		goto again;
+
+	case STATE_BIT_START:
+		if (!ev.pulse && geq_margin(ev.duration, RC5_TRAILER, RC5_UNIT / 2)) {
+			data->state = STATE_FINISHED;
+			goto again;
+		}
+
+		if (!eq_margin(ev.duration, RC5_BIT_START, RC5_UNIT / 2))
+			break;
+
+		data->bits <<= 1;
+		if (!ev.pulse)
+			data->bits |= 1;
+		data->count++;
+		data->state = STATE_BIT_END;
+		return 0;
+
+	case STATE_BIT_END:
+		if (data->count == CHECK_RC5X_NBITS)
+			data->state = STATE_CHECK_RC5X;
+		else
+			data->state = STATE_BIT_START;
+
+		decrease_duration(&ev, RC5_BIT_END);
+		goto again;
+
+	case STATE_CHECK_RC5X:
+		if (!ev.pulse && geq_margin(ev.duration, RC5X_SPACE, RC5_UNIT / 2)) {
+			data->is_rc5x = true;
+			decrease_duration(&ev, RC5X_SPACE);
+		} else
+			data->is_rc5x = false;
+		data->state = STATE_BIT_START;
+		goto again;
+
+	case STATE_FINISHED:
+		if (ev.pulse)
+			break;
+
+		if (data->is_rc5x && data->count == RC5X_NBITS) {
+			/* RC5X */
+			u8 xdata, command, system;
+			if (!(dev->enabled_protocols & RC_PROTO_BIT_RC5X_20)) {
+				data->state = STATE_INACTIVE;
+				return 0;
+			}
+			xdata    = (data->bits & 0x0003F) >> 0;
+			command  = (data->bits & 0x00FC0) >> 6;
+			system   = (data->bits & 0x1F000) >> 12;
+			toggle   = (data->bits & 0x20000) ? 1 : 0;
+			command += (data->bits & 0x40000) ? 0 : 0x40;
+			scancode = system << 16 | command << 8 | xdata;
+			protocol = RC_PROTO_RC5X_20;
+
+		} else if (!data->is_rc5x && data->count == RC5_NBITS) {
+			/* RC5 */
+			u8 command, system;
+			if (!(dev->enabled_protocols & RC_PROTO_BIT_RC5)) {
+				data->state = STATE_INACTIVE;
+				return 0;
+			}
+			command  = (data->bits & 0x0003F) >> 0;
+			system   = (data->bits & 0x007C0) >> 6;
+			toggle   = (data->bits & 0x00800) ? 1 : 0;
+			command += (data->bits & 0x01000) ? 0 : 0x40;
+			scancode = system << 8 | command;
+			protocol = RC_PROTO_RC5;
+
+		} else if (!data->is_rc5x && data->count == RC5_SZ_NBITS) {
+			/* RC5 StreamZap */
+			u8 command, system;
+			if (!(dev->enabled_protocols & RC_PROTO_BIT_RC5_SZ)) {
+				data->state = STATE_INACTIVE;
+				return 0;
+			}
+			command  = (data->bits & 0x0003F) >> 0;
+			system   = (data->bits & 0x02FC0) >> 6;
+			toggle   = (data->bits & 0x01000) ? 1 : 0;
+			scancode = system << 6 | command;
+			protocol = RC_PROTO_RC5_SZ;
+
+		} else
+			break;
+
+		dev_dbg(&dev->dev, "RC5(x/sz) scancode 0x%06x (p: %u, t: %u)\n",
+			scancode, protocol, toggle);
+
+		rc_keydown(dev, protocol, scancode, toggle);
+		data->state = STATE_INACTIVE;
+		return 0;
+	}
+
+out:
+	dev_dbg(&dev->dev, "RC5(x/sz) decode failed at state %i count %d (%uus %s)\n",
+		data->state, data->count, TO_US(ev.duration), TO_STR(ev.pulse));
+	data->state = STATE_INACTIVE;
+	return -EINVAL;
+}
+
+static const struct ir_raw_timings_manchester ir_rc5_timings = {
+	.leader_pulse		= RC5_UNIT,
+	.clock			= RC5_UNIT,
+	.trailer_space		= RC5_UNIT * 10,
+};
+
+static const struct ir_raw_timings_manchester ir_rc5x_timings[2] = {
+	{
+		.leader_pulse		= RC5_UNIT,
+		.clock			= RC5_UNIT,
+		.trailer_space		= RC5X_SPACE,
+	},
+	{
+		.clock			= RC5_UNIT,
+		.trailer_space		= RC5_UNIT * 10,
+	},
+};
+
+static const struct ir_raw_timings_manchester ir_rc5_sz_timings = {
+	.leader_pulse			= RC5_UNIT,
+	.clock				= RC5_UNIT,
+	.trailer_space			= RC5_UNIT * 10,
+};
+
+/**
+ * ir_rc5_encode() - Encode a scancode as a stream of raw events
+ *
+ * @protocol:	protocol variant to encode
+ * @scancode:	scancode to encode
+ * @events:	array of raw ir events to write into
+ * @max:	maximum size of @events
+ *
+ * Returns:	The number of events written.
+ *		-ENOBUFS if there isn't enough space in the array to fit the
+ *		encoding. In this case all @max events will have been written.
+ *		-EINVAL if the scancode is ambiguous or invalid.
+ */
+static int ir_rc5_encode(enum rc_proto protocol, u32 scancode,
+			 struct ir_raw_event *events, unsigned int max)
+{
+	int ret;
+	struct ir_raw_event *e = events;
+	unsigned int data, xdata, command, commandx, system, pre_space_data;
+
+	/* Detect protocol and convert scancode to raw data */
+	if (protocol == RC_PROTO_RC5) {
+		/* decode scancode */
+		command  = (scancode & 0x003f) >> 0;
+		commandx = (scancode & 0x0040) >> 6;
+		system   = (scancode & 0x1f00) >> 8;
+		/* encode data */
+		data = !commandx << 12 | system << 6 | command;
+
+		/* First bit is encoded by leader_pulse */
+		ret = ir_raw_gen_manchester(&e, max, &ir_rc5_timings,
+					    RC5_NBITS - 1, data);
+		if (ret < 0)
+			return ret;
+	} else if (protocol == RC_PROTO_RC5X_20) {
+		/* decode scancode */
+		xdata    = (scancode & 0x00003f) >> 0;
+		command  = (scancode & 0x003f00) >> 8;
+		commandx = !(scancode & 0x004000);
+		system   = (scancode & 0x1f0000) >> 16;
+
+		/* encode data */
+		data = commandx << 18 | system << 12 | command << 6 | xdata;
+
+		/* First bit is encoded by leader_pulse */
+		pre_space_data = data >> (RC5X_NBITS - CHECK_RC5X_NBITS);
+		ret = ir_raw_gen_manchester(&e, max, &ir_rc5x_timings[0],
+					    CHECK_RC5X_NBITS - 1,
+					    pre_space_data);
+		if (ret < 0)
+			return ret;
+		ret = ir_raw_gen_manchester(&e, max - (e - events),
+					    &ir_rc5x_timings[1],
+					    RC5X_NBITS - CHECK_RC5X_NBITS,
+					    data);
+		if (ret < 0)
+			return ret;
+	} else if (protocol == RC_PROTO_RC5_SZ) {
+		/* RC5-SZ scancode is raw enough for Manchester as it is */
+		/* First bit is encoded by leader_pulse */
+		ret = ir_raw_gen_manchester(&e, max, &ir_rc5_sz_timings,
+					    RC5_SZ_NBITS - 1,
+					    scancode & 0x2fff);
+		if (ret < 0)
+			return ret;
+	} else {
+		return -EINVAL;
+	}
+
+	return e - events;
+}
+
+static struct ir_raw_handler rc5_handler = {
+	.protocols	= RC_PROTO_BIT_RC5 | RC_PROTO_BIT_RC5X_20 |
+							RC_PROTO_BIT_RC5_SZ,
+	.decode		= ir_rc5_decode,
+	.encode		= ir_rc5_encode,
+	.carrier	= 36000,
+	.min_timeout	= RC5_TRAILER,
+};
+
+static int __init ir_rc5_decode_init(void)
+{
+	ir_raw_handler_register(&rc5_handler);
+
+	printk(KERN_INFO "IR RC5(x/sz) protocol handler initialized\n");
+	return 0;
+}
+
+static void __exit ir_rc5_decode_exit(void)
+{
+	ir_raw_handler_unregister(&rc5_handler);
+}
+
+module_init(ir_rc5_decode_init);
+module_exit(ir_rc5_decode_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Mauro Carvalho Chehab and Jarod Wilson");
+MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
+MODULE_DESCRIPTION("RC5(x/sz) IR protocol decoder");