v4.19.13 snapshot.
diff --git a/drivers/media/rc/ir-imon-decoder.c b/drivers/media/rc/ir-imon-decoder.c
new file mode 100644
index 0000000..67c1b0c
--- /dev/null
+++ b/drivers/media/rc/ir-imon-decoder.c
@@ -0,0 +1,323 @@
+// SPDX-License-Identifier: GPL-2.0+
+// ir-imon-decoder.c - handle iMon protocol
+//
+// Copyright (C) 2018 by Sean Young <sean@mess.org>
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include "rc-core-priv.h"
+
+#define IMON_UNIT 415662 /* ns */
+#define IMON_BITS 30
+#define IMON_CHKBITS (BIT(30) | BIT(25) | BIT(24) | BIT(22) | \
+ BIT(21) | BIT(20) | BIT(19) | BIT(18) | \
+ BIT(17) | BIT(16) | BIT(14) | BIT(13) | \
+ BIT(12) | BIT(11) | BIT(10) | BIT(9))
+
+/*
+ * This protocol has 30 bits. The format is one IMON_UNIT header pulse,
+ * followed by 30 bits. Each bit is one IMON_UNIT check field, and then
+ * one IMON_UNIT field with the actual bit (1=space, 0=pulse).
+ * The check field is always space for some bits, for others it is pulse if
+ * both the preceding and current bit are zero, else space. IMON_CHKBITS
+ * defines which bits are of type check.
+ *
+ * There is no way to distinguish an incomplete message from one where
+ * the lower bits are all set, iow. the last pulse is for the lowest
+ * bit which is 0.
+ */
+enum imon_state {
+ STATE_INACTIVE,
+ STATE_BIT_CHK,
+ STATE_BIT_START,
+ STATE_FINISHED,
+ STATE_ERROR,
+};
+
+static void ir_imon_decode_scancode(struct rc_dev *dev)
+{
+ struct imon_dec *imon = &dev->raw->imon;
+
+ /* Keyboard/Mouse toggle */
+ if (imon->bits == 0x299115b7)
+ imon->stick_keyboard = !imon->stick_keyboard;
+
+ if ((imon->bits & 0xfc0000ff) == 0x680000b7) {
+ int rel_x, rel_y;
+ u8 buf;
+
+ buf = imon->bits >> 16;
+ rel_x = (buf & 0x08) | (buf & 0x10) >> 2 |
+ (buf & 0x20) >> 4 | (buf & 0x40) >> 6;
+ if (imon->bits & 0x02000000)
+ rel_x |= ~0x0f;
+ buf = imon->bits >> 8;
+ rel_y = (buf & 0x08) | (buf & 0x10) >> 2 |
+ (buf & 0x20) >> 4 | (buf & 0x40) >> 6;
+ if (imon->bits & 0x01000000)
+ rel_y |= ~0x0f;
+
+ if (rel_x && rel_y && imon->stick_keyboard) {
+ if (abs(rel_y) > abs(rel_x))
+ imon->bits = rel_y > 0 ?
+ 0x289515b7 : /* KEY_DOWN */
+ 0x2aa515b7; /* KEY_UP */
+ else
+ imon->bits = rel_x > 0 ?
+ 0x2ba515b7 : /* KEY_RIGHT */
+ 0x29a515b7; /* KEY_LEFT */
+ }
+
+ if (!imon->stick_keyboard) {
+ struct lirc_scancode lsc = {
+ .scancode = imon->bits,
+ .rc_proto = RC_PROTO_IMON,
+ };
+
+ ir_lirc_scancode_event(dev, &lsc);
+
+ input_event(imon->idev, EV_MSC, MSC_SCAN, imon->bits);
+
+ input_report_rel(imon->idev, REL_X, rel_x);
+ input_report_rel(imon->idev, REL_Y, rel_y);
+
+ input_report_key(imon->idev, BTN_LEFT,
+ (imon->bits & 0x00010000) != 0);
+ input_report_key(imon->idev, BTN_RIGHT,
+ (imon->bits & 0x00040000) != 0);
+ input_sync(imon->idev);
+ return;
+ }
+ }
+
+ rc_keydown(dev, RC_PROTO_IMON, imon->bits, 0);
+}
+
+/**
+ * ir_imon_decode() - Decode one iMON 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_imon_decode(struct rc_dev *dev, struct ir_raw_event ev)
+{
+ struct imon_dec *data = &dev->raw->imon;
+
+ if (!is_timing_event(ev)) {
+ if (ev.reset)
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
+
+ dev_dbg(&dev->dev,
+ "iMON decode started at state %d bitno %d (%uus %s)\n",
+ data->state, data->count, TO_US(ev.duration),
+ TO_STR(ev.pulse));
+
+ /*
+ * Since iMON protocol is a series of bits, if at any point
+ * we encounter an error, make sure that any remaining bits
+ * aren't parsed as a scancode made up of less bits.
+ *
+ * Note that if the stick is held, then the remote repeats
+ * the scancode with about 12ms between them. So, make sure
+ * we have at least 10ms of space after an error. That way,
+ * we're at a new scancode.
+ */
+ if (data->state == STATE_ERROR) {
+ if (!ev.pulse && ev.duration > MS_TO_NS(10))
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
+
+ for (;;) {
+ if (!geq_margin(ev.duration, IMON_UNIT, IMON_UNIT / 2))
+ return 0;
+
+ decrease_duration(&ev, IMON_UNIT);
+
+ switch (data->state) {
+ case STATE_INACTIVE:
+ if (ev.pulse) {
+ data->state = STATE_BIT_CHK;
+ data->bits = 0;
+ data->count = IMON_BITS;
+ }
+ break;
+ case STATE_BIT_CHK:
+ if (IMON_CHKBITS & BIT(data->count))
+ data->last_chk = ev.pulse;
+ else if (ev.pulse)
+ goto err_out;
+ data->state = STATE_BIT_START;
+ break;
+ case STATE_BIT_START:
+ data->bits <<= 1;
+ if (!ev.pulse)
+ data->bits |= 1;
+
+ if (IMON_CHKBITS & BIT(data->count)) {
+ if (data->last_chk != !(data->bits & 3))
+ goto err_out;
+ }
+
+ if (!data->count--)
+ data->state = STATE_FINISHED;
+ else
+ data->state = STATE_BIT_CHK;
+ break;
+ case STATE_FINISHED:
+ if (ev.pulse)
+ goto err_out;
+ ir_imon_decode_scancode(dev);
+ data->state = STATE_INACTIVE;
+ break;
+ }
+ }
+
+err_out:
+ dev_dbg(&dev->dev,
+ "iMON decode failed at state %d bitno %d (%uus %s)\n",
+ data->state, data->count, TO_US(ev.duration),
+ TO_STR(ev.pulse));
+
+ data->state = STATE_ERROR;
+
+ return -EINVAL;
+}
+
+/**
+ * ir_imon_encode() - Encode a scancode as a stream of raw events
+ *
+ * @protocol: protocol 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.
+ */
+static int ir_imon_encode(enum rc_proto protocol, u32 scancode,
+ struct ir_raw_event *events, unsigned int max)
+{
+ struct ir_raw_event *e = events;
+ int i, pulse;
+
+ if (!max--)
+ return -ENOBUFS;
+ init_ir_raw_event_duration(e, 1, IMON_UNIT);
+
+ for (i = IMON_BITS; i >= 0; i--) {
+ if (BIT(i) & IMON_CHKBITS)
+ pulse = !(scancode & (BIT(i) | BIT(i + 1)));
+ else
+ pulse = 0;
+
+ if (pulse == e->pulse) {
+ e->duration += IMON_UNIT;
+ } else {
+ if (!max--)
+ return -ENOBUFS;
+ init_ir_raw_event_duration(++e, pulse, IMON_UNIT);
+ }
+
+ pulse = !(scancode & BIT(i));
+
+ if (pulse == e->pulse) {
+ e->duration += IMON_UNIT;
+ } else {
+ if (!max--)
+ return -ENOBUFS;
+ init_ir_raw_event_duration(++e, pulse, IMON_UNIT);
+ }
+ }
+
+ if (e->pulse)
+ e++;
+
+ return e - events;
+}
+
+static int ir_imon_register(struct rc_dev *dev)
+{
+ struct input_dev *idev;
+ struct imon_dec *imon = &dev->raw->imon;
+ int ret;
+
+ idev = input_allocate_device();
+ if (!idev)
+ return -ENOMEM;
+
+ snprintf(imon->name, sizeof(imon->name),
+ "iMON PAD Stick (%s)", dev->device_name);
+ idev->name = imon->name;
+ idev->phys = dev->input_phys;
+
+ /* Mouse bits */
+ set_bit(EV_REL, idev->evbit);
+ set_bit(EV_KEY, idev->evbit);
+ set_bit(REL_X, idev->relbit);
+ set_bit(REL_Y, idev->relbit);
+ set_bit(BTN_LEFT, idev->keybit);
+ set_bit(BTN_RIGHT, idev->keybit);
+
+ /* Report scancodes too */
+ set_bit(EV_MSC, idev->evbit);
+ set_bit(MSC_SCAN, idev->mscbit);
+
+ input_set_drvdata(idev, imon);
+
+ ret = input_register_device(idev);
+ if (ret < 0) {
+ input_free_device(idev);
+ return -EIO;
+ }
+
+ imon->idev = idev;
+ imon->stick_keyboard = false;
+
+ return 0;
+}
+
+static int ir_imon_unregister(struct rc_dev *dev)
+{
+ struct imon_dec *imon = &dev->raw->imon;
+
+ input_unregister_device(imon->idev);
+ imon->idev = NULL;
+
+ return 0;
+}
+
+static struct ir_raw_handler imon_handler = {
+ .protocols = RC_PROTO_BIT_IMON,
+ .decode = ir_imon_decode,
+ .encode = ir_imon_encode,
+ .carrier = 38000,
+ .raw_register = ir_imon_register,
+ .raw_unregister = ir_imon_unregister,
+ .min_timeout = IMON_UNIT * IMON_BITS * 2,
+};
+
+static int __init ir_imon_decode_init(void)
+{
+ ir_raw_handler_register(&imon_handler);
+
+ pr_info("IR iMON protocol handler initialized\n");
+ return 0;
+}
+
+static void __exit ir_imon_decode_exit(void)
+{
+ ir_raw_handler_unregister(&imon_handler);
+}
+
+module_init(ir_imon_decode_init);
+module_exit(ir_imon_decode_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sean Young <sean@mess.org>");
+MODULE_DESCRIPTION("iMON IR protocol decoder");