// 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);