xref: /kernel/linux/linux-5.10/drivers/media/usb/dvb-usb/dvb-usb-remote.c

// SPDX-License-Identifier: GPL-2.0
/* dvb-usb-remote.c is part of the DVB USB library.
 *
 * Copyright (C) 2004-6 Patrick Boettcher (patrick.boettcher@posteo.de)
 * see dvb-usb-init.c for copyright information.
 *
 * This file contains functions for initializing the input-device and for handling remote-control-queries.
 */
#include "dvb-usb-common.h"
#include <linux/usb/input.h>

static unsigned int
legacy_dvb_usb_get_keymap_index(const struct input_keymap_entry *ke,
				struct rc_map_table *keymap,
				unsigned int keymap_size)
{
	unsigned int index;
	unsigned int scancode;

	if (ke->flags & INPUT_KEYMAP_BY_INDEX) {
		index = ke->index;
	} else {
		if (input_scancode_to_scalar(ke, &scancode))
			return keymap_size;

		/* See if we can match the raw key code. */
		for (index = 0; index < keymap_size; index++)
			if (keymap[index].scancode == scancode)
				break;

		/* See if there is an unused hole in the map */
		if (index >= keymap_size) {
			for (index = 0; index < keymap_size; index++) {
				if (keymap[index].keycode == KEY_RESERVED ||
				    keymap[index].keycode == KEY_UNKNOWN) {
					break;
				}
			}
		}
	}

	return index;
}

static int legacy_dvb_usb_getkeycode(struct input_dev *dev,
				     struct input_keymap_entry *ke)
{
	struct dvb_usb_device *d = input_get_drvdata(dev);
	struct rc_map_table *keymap = d->props.rc.legacy.rc_map_table;
	unsigned int keymap_size = d->props.rc.legacy.rc_map_size;
	unsigned int index;

	index = legacy_dvb_usb_get_keymap_index(ke, keymap, keymap_size);
	if (index >= keymap_size)
		return -EINVAL;

	ke->keycode = keymap[index].keycode;
	if (ke->keycode == KEY_UNKNOWN)
		ke->keycode = KEY_RESERVED;
	ke->len = sizeof(keymap[index].scancode);
	memcpy(&ke->scancode, &keymap[index].scancode, ke->len);
	ke->index = index;

	return 0;
}

static int legacy_dvb_usb_setkeycode(struct input_dev *dev,
				     const struct input_keymap_entry *ke,
				     unsigned int *old_keycode)
{
	struct dvb_usb_device *d = input_get_drvdata(dev);
	struct rc_map_table *keymap = d->props.rc.legacy.rc_map_table;
	unsigned int keymap_size = d->props.rc.legacy.rc_map_size;
	unsigned int index;

	index = legacy_dvb_usb_get_keymap_index(ke, keymap, keymap_size);
	/*
	 * FIXME: Currently, it is not possible to increase the size of
	 * scancode table. For it to happen, one possibility
	 * would be to allocate a table with key_map_size + 1,
	 * copying data, appending the new key on it, and freeing
	 * the old one - or maybe just allocating some spare space
	 */
	if (index >= keymap_size)
		return -EINVAL;

	*old_keycode = keymap[index].keycode;
	keymap->keycode = ke->keycode;
	__set_bit(ke->keycode, dev->keybit);

	if (*old_keycode != KEY_RESERVED) {
		__clear_bit(*old_keycode, dev->keybit);
		for (index = 0; index < keymap_size; index++) {
			if (keymap[index].keycode == *old_keycode) {
				__set_bit(*old_keycode, dev->keybit);
				break;
			}
		}
	}

	return 0;
}

/* Remote-control poll function - called every dib->rc_query_interval ms to see
 * whether the remote control has received anything.
 *
 * TODO: Fix the repeat rate of the input device.
 */
static void legacy_dvb_usb_read_remote_control(struct work_struct *work)
{
	struct dvb_usb_device *d =
		container_of(work, struct dvb_usb_device, rc_query_work.work);
	u32 event;
	int state;

	/* TODO: need a lock here.  We can simply skip checking for the remote control
	   if we're busy. */

	/* when the parameter has been set to 1 via sysfs while the driver was running */
	if (dvb_usb_disable_rc_polling)
		return;

	if (d->props.rc.legacy.rc_query(d,&event,&state)) {
		err("error while querying for an remote control event.");
		goto schedule;
	}


	switch (state) {
		case REMOTE_NO_KEY_PRESSED:
			break;
		case REMOTE_KEY_PRESSED:
			deb_rc("key pressed\n");
			d->last_event = event;
			input_event(d->input_dev, EV_KEY, event, 1);
			input_sync(d->input_dev);
			input_event(d->input_dev, EV_KEY, d->last_event, 0);
			input_sync(d->input_dev);
			break;
		case REMOTE_KEY_REPEAT:
			deb_rc("key repeated\n");
			input_event(d->input_dev, EV_KEY, event, 1);
			input_sync(d->input_dev);
			input_event(d->input_dev, EV_KEY, d->last_event, 0);
			input_sync(d->input_dev);
			break;
		default:
			break;
	}

/* improved repeat handling ???
	switch (state) {
		case REMOTE_NO_KEY_PRESSED:
			deb_rc("NO KEY PRESSED\n");
			if (d->last_state != REMOTE_NO_KEY_PRESSED) {
				deb_rc("releasing event %d\n",d->last_event);
				input_event(d->rc_input_dev, EV_KEY, d->last_event, 0);
				input_sync(d->rc_input_dev);
			}
			d->last_state = REMOTE_NO_KEY_PRESSED;
			d->last_event = 0;
			break;
		case REMOTE_KEY_PRESSED:
			deb_rc("KEY PRESSED\n");
			deb_rc("pressing event %d\n",event);

			input_event(d->rc_input_dev, EV_KEY, event, 1);
			input_sync(d->rc_input_dev);

			d->last_event = event;
			d->last_state = REMOTE_KEY_PRESSED;
			break;
		case REMOTE_KEY_REPEAT:
			deb_rc("KEY_REPEAT\n");
			if (d->last_state != REMOTE_NO_KEY_PRESSED) {
				deb_rc("repeating event %d\n",d->last_event);
				input_event(d->rc_input_dev, EV_KEY, d->last_event, 2);
				input_sync(d->rc_input_dev);
				d->last_state = REMOTE_KEY_REPEAT;
			}
		default:
			break;
	}
*/

schedule:
	schedule_delayed_work(&d->rc_query_work,msecs_to_jiffies(d->props.rc.legacy.rc_interval));
}

static int legacy_dvb_usb_remote_init(struct dvb_usb_device *d)
{
	int i, err, rc_interval;
	struct input_dev *input_dev;

	input_dev = input_allocate_device();
	if (!input_dev)
		return -ENOMEM;

	input_dev->evbit[0] = BIT_MASK(EV_KEY);
	input_dev->name = "IR-receiver inside an USB DVB receiver";
	input_dev->phys = d->rc_phys;
	usb_to_input_id(d->udev, &input_dev->id);
	input_dev->dev.parent = &d->udev->dev;
	d->input_dev = input_dev;
	d->rc_dev = NULL;

	input_dev->getkeycode = legacy_dvb_usb_getkeycode;
	input_dev->setkeycode = legacy_dvb_usb_setkeycode;

	/* set the bits for the keys */
	deb_rc("key map size: %d\n", d->props.rc.legacy.rc_map_size);
	for (i = 0; i < d->props.rc.legacy.rc_map_size; i++) {
		deb_rc("setting bit for event %d item %d\n",
			d->props.rc.legacy.rc_map_table[i].keycode, i);
		set_bit(d->props.rc.legacy.rc_map_table[i].keycode, input_dev->keybit);
	}

	/* setting these two values to non-zero, we have to manage key repeats */
	input_dev->rep[REP_PERIOD] = d->props.rc.legacy.rc_interval;
	input_dev->rep[REP_DELAY]  = d->props.rc.legacy.rc_interval + 150;

	input_set_drvdata(input_dev, d);

	err = input_register_device(input_dev);
	if (err)
		input_free_device(input_dev);

	rc_interval = d->props.rc.legacy.rc_interval;

	INIT_DELAYED_WORK(&d->rc_query_work, legacy_dvb_usb_read_remote_control);

	info("schedule remote query interval to %d msecs.", rc_interval);
	schedule_delayed_work(&d->rc_query_work,
			      msecs_to_jiffies(rc_interval));

	d->state |= DVB_USB_STATE_REMOTE;

	return err;
}

/* Remote-control poll function - called every dib->rc_query_interval ms to see
 * whether the remote control has received anything.
 *
 * TODO: Fix the repeat rate of the input device.
 */
static void dvb_usb_read_remote_control(struct work_struct *work)
{
	struct dvb_usb_device *d =
		container_of(work, struct dvb_usb_device, rc_query_work.work);
	int err;

	/* TODO: need a lock here.  We can simply skip checking for the remote control
	   if we're busy. */

	/* when the parameter has been set to 1 via sysfs while the
	 * driver was running, or when bulk mode is enabled after IR init
	 */
	if (dvb_usb_disable_rc_polling || d->props.rc.core.bulk_mode)
		return;

	err = d->props.rc.core.rc_query(d);
	if (err)
		err("error %d while querying for an remote control event.", err);

	schedule_delayed_work(&d->rc_query_work,
			      msecs_to_jiffies(d->props.rc.core.rc_interval));
}

static int rc_core_dvb_usb_remote_init(struct dvb_usb_device *d)
{
	int err, rc_interval;
	struct rc_dev *dev;

	dev = rc_allocate_device(d->props.rc.core.driver_type);
	if (!dev)
		return -ENOMEM;

	dev->driver_name = d->props.rc.core.module_name;
	dev->map_name = d->props.rc.core.rc_codes;
	dev->change_protocol = d->props.rc.core.change_protocol;
	dev->allowed_protocols = d->props.rc.core.allowed_protos;
	usb_to_input_id(d->udev, &dev->input_id);
	dev->device_name = d->desc->name;
	dev->input_phys = d->rc_phys;
	dev->dev.parent = &d->udev->dev;
	dev->priv = d;
	dev->scancode_mask = d->props.rc.core.scancode_mask;

	err = rc_register_device(dev);
	if (err < 0) {
		rc_free_device(dev);
		return err;
	}

	d->input_dev = NULL;
	d->rc_dev = dev;

	if (!d->props.rc.core.rc_query || d->props.rc.core.bulk_mode)
		return 0;

	/* Polling mode - initialize a work queue for handling it */
	INIT_DELAYED_WORK(&d->rc_query_work, dvb_usb_read_remote_control);

	rc_interval = d->props.rc.core.rc_interval;

	info("schedule remote query interval to %d msecs.", rc_interval);
	schedule_delayed_work(&d->rc_query_work,
			      msecs_to_jiffies(rc_interval));

	return 0;
}

int dvb_usb_remote_init(struct dvb_usb_device *d)
{
	int err;

	if (dvb_usb_disable_rc_polling)
		return 0;

	if (d->props.rc.legacy.rc_map_table && d->props.rc.legacy.rc_query)
		d->props.rc.mode = DVB_RC_LEGACY;
	else if (d->props.rc.core.rc_codes)
		d->props.rc.mode = DVB_RC_CORE;
	else
		return 0;

	usb_make_path(d->udev, d->rc_phys, sizeof(d->rc_phys));
	strlcat(d->rc_phys, "/ir0", sizeof(d->rc_phys));

	/* Start the remote-control polling. */
	if (d->props.rc.legacy.rc_interval < 40)
		d->props.rc.legacy.rc_interval = 100; /* default */

	if (d->props.rc.mode == DVB_RC_LEGACY)
		err = legacy_dvb_usb_remote_init(d);
	else
		err = rc_core_dvb_usb_remote_init(d);
	if (err)
		return err;

	d->state |= DVB_USB_STATE_REMOTE;

	return 0;
}

int dvb_usb_remote_exit(struct dvb_usb_device *d)
{
	if (d->state & DVB_USB_STATE_REMOTE) {
		cancel_delayed_work_sync(&d->rc_query_work);
		if (d->props.rc.mode == DVB_RC_LEGACY)
			input_unregister_device(d->input_dev);
		else
			rc_unregister_device(d->rc_dev);
	}
	d->state &= ~DVB_USB_STATE_REMOTE;
	return 0;
}

#define DVB_USB_RC_NEC_EMPTY           0x00
#define DVB_USB_RC_NEC_KEY_PRESSED     0x01
#define DVB_USB_RC_NEC_KEY_REPEATED    0x02
int dvb_usb_nec_rc_key_to_event(struct dvb_usb_device *d,
		u8 keybuf[5], u32 *event, int *state)
{
	int i;
	struct rc_map_table *keymap = d->props.rc.legacy.rc_map_table;
	*event = 0;
	*state = REMOTE_NO_KEY_PRESSED;
	switch (keybuf[0]) {
		case DVB_USB_RC_NEC_EMPTY:
			break;
		case DVB_USB_RC_NEC_KEY_PRESSED:
			if ((u8) ~keybuf[1] != keybuf[2] ||
				(u8) ~keybuf[3] != keybuf[4]) {
				deb_err("remote control checksum failed.\n");
				break;
			}
			/* See if we can match the raw key code. */
			for (i = 0; i < d->props.rc.legacy.rc_map_size; i++)
				if (rc5_custom(&keymap[i]) == keybuf[1] &&
					rc5_data(&keymap[i]) == keybuf[3]) {
					*event = keymap[i].keycode;
					*state = REMOTE_KEY_PRESSED;
					return 0;
				}
			deb_err("key mapping failed - no appropriate key found in keymapping\n");
			break;
		case DVB_USB_RC_NEC_KEY_REPEATED:
			*state = REMOTE_KEY_REPEAT;
			break;
		default:
			deb_err("unknown type of remote status: %d\n",keybuf[0]);
			break;
	}
	return 0;
}
EXPORT_SYMBOL(dvb_usb_nec_rc_key_to_event);