// SPDX-License-Identifier: GPL-2.0+
/*
 * Digital Beep Input Interface for HD-audio codec
 *
 * Author: Matt Ranostay <matt.ranostay@konsulko.com>
 * Copyright (c) 2008 Embedded Alley Solutions Inc
 */

#include <linux/input.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/export.h>
#include <sound/core.h>
#include "hda_beep.h"
#include "hda_local.h"

enum {
        DIGBEEP_HZ_STEP = 46875,        /* 46.875 Hz */
        DIGBEEP_HZ_MIN = 93750,         /* 93.750 Hz */
        DIGBEEP_HZ_MAX = 12000000,      /* 12 KHz */
};

/* generate or stop tone */
static void generate_tone(struct hda_beep *beep, int tone)
{
        struct hda_codec *codec = beep->codec;

        if (tone && !beep->playing) {
                snd_hda_power_up(codec);
                if (beep->power_hook)
                        beep->power_hook(beep, true);
                beep->playing = 1;
        }
        snd_hda_codec_write(codec, beep->nid, 0,
                            AC_VERB_SET_BEEP_CONTROL, tone);
        if (!tone && beep->playing) {
                beep->playing = 0;
                if (beep->power_hook)
                        beep->power_hook(beep, false);
                snd_hda_power_down(codec);
        }
}

static void snd_hda_generate_beep(struct work_struct *work)
{
        struct hda_beep *beep =
                container_of(work, struct hda_beep, beep_work);

        if (beep->enabled)
                generate_tone(beep, beep->tone);
}

/* (non-standard) Linear beep tone calculation for IDT/STAC codecs 
 *
 * The tone frequency of beep generator on IDT/STAC codecs is
 * defined from the 8bit tone parameter, in Hz,
 *    freq = 48000 * (257 - tone) / 1024
 * that is from 12kHz to 93.75Hz in steps of 46.875 Hz
 */
static int beep_linear_tone(struct hda_beep *beep, int hz)
{
        if (hz <= 0)
                return 0;
        hz *= 1000; /* fixed point */
        hz = hz - DIGBEEP_HZ_MIN
                + DIGBEEP_HZ_STEP / 2; /* round to nearest step */
        if (hz < 0)
                hz = 0; /* turn off PC beep*/
        else if (hz >= (DIGBEEP_HZ_MAX - DIGBEEP_HZ_MIN))
                hz = 1; /* max frequency */
        else {
                hz /= DIGBEEP_HZ_STEP;
                hz = 255 - hz;
        }
        return hz;
}

/* HD-audio standard beep tone parameter calculation
 *
 * The tone frequency in Hz is calculated as
 *   freq = 48000 / (tone * 4)
 * from 47Hz to 12kHz
 */
static int beep_standard_tone(struct hda_beep *beep, int hz)
{
        if (hz <= 0)
                return 0; /* disabled */
        hz = 12000 / hz;
        if (hz > 0xff)
                return 0xff;
        if (hz <= 0)
                return 1;
        return hz;
}

static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
                                unsigned int code, int hz)
{
        struct hda_beep *beep = input_get_drvdata(dev);

        switch (code) {
        case SND_BELL:
                if (hz)
                        hz = 1000;
                /* fallthru */
        case SND_TONE:
                if (beep->linear_tone)
                        beep->tone = beep_linear_tone(beep, hz);
                else
                        beep->tone = beep_standard_tone(beep, hz);
                break;
        default:
                return -1;
        }

        /* schedule beep event */
        schedule_work(&beep->beep_work);
        return 0;
}

static void turn_off_beep(struct hda_beep *beep)
{
        cancel_work_sync(&beep->beep_work);
        if (beep->playing) {
                /* turn off beep */
                generate_tone(beep, 0);
        }
}

/**
 * snd_hda_enable_beep_device - Turn on/off beep sound
 * @codec: the HDA codec
 * @enable: flag to turn on/off
 */
int snd_hda_enable_beep_device(struct hda_codec *codec, int enable)
{
        struct hda_beep *beep = codec->beep;
        if (!beep)
                return 0;
        enable = !!enable;
        if (beep->enabled != enable) {
                beep->enabled = enable;
                if (!enable)
                        turn_off_beep(beep);
                return 1;
        }
        return 0;
}
EXPORT_SYMBOL_GPL(snd_hda_enable_beep_device);

static int beep_dev_register(struct snd_device *device)
{
        struct hda_beep *beep = device->device_data;
        int err;

        err = input_register_device(beep->dev);
        if (!err)
                beep->registered = true;
        return err;
}

static int beep_dev_disconnect(struct snd_device *device)
{
        struct hda_beep *beep = device->device_data;

        if (beep->registered)
                input_unregister_device(beep->dev);
        else
                input_free_device(beep->dev);
        turn_off_beep(beep);
        return 0;
}

static int beep_dev_free(struct snd_device *device)
{
        struct hda_beep *beep = device->device_data;

        beep->codec->beep = NULL;
        kfree(beep);
        return 0;
}

/**
 * snd_hda_attach_beep_device - Attach a beep input device
 * @codec: the HDA codec
 * @nid: beep NID
 *
 * Attach a beep object to the given widget.  If beep hint is turned off
 * explicitly or beep_mode of the codec is turned off, this doesn't nothing.
 *
 * Currently, only one beep device is allowed to each codec.
 */
int snd_hda_attach_beep_device(struct hda_codec *codec, int nid)
{
        static struct snd_device_ops ops = {
                .dev_register = beep_dev_register,
                .dev_disconnect = beep_dev_disconnect,
                .dev_free = beep_dev_free,
        };
        struct input_dev *input_dev;
        struct hda_beep *beep;
        int err;

        if (!snd_hda_get_bool_hint(codec, "beep"))
                return 0; /* disabled explicitly by hints */
        if (codec->beep_mode == HDA_BEEP_MODE_OFF)
                return 0; /* disabled by module option */

        beep = kzalloc(sizeof(*beep), GFP_KERNEL);
        if (beep == NULL)
                return -ENOMEM;
        snprintf(beep->phys, sizeof(beep->phys),
                "card%d/codec#%d/beep0", codec->card->number, codec->addr);
        /* enable linear scale */
        snd_hda_codec_write_cache(codec, nid, 0,
                AC_VERB_SET_DIGI_CONVERT_2, 0x01);

        beep->nid = nid;
        beep->codec = codec;
        codec->beep = beep;

        INIT_WORK(&beep->beep_work, &snd_hda_generate_beep);
        mutex_init(&beep->mutex);

        input_dev = input_allocate_device();
        if (!input_dev) {
                err = -ENOMEM;
                goto err_free;
        }

        /* setup digital beep device */
        input_dev->name = "HDA Digital PCBeep";
        input_dev->phys = beep->phys;
        input_dev->id.bustype = BUS_PCI;
        input_dev->dev.parent = &codec->card->card_dev;

        input_dev->id.vendor = codec->core.vendor_id >> 16;
        input_dev->id.product = codec->core.vendor_id & 0xffff;
        input_dev->id.version = 0x01;

        input_dev->evbit[0] = BIT_MASK(EV_SND);
        input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
        input_dev->event = snd_hda_beep_event;
        input_set_drvdata(input_dev, beep);

        beep->dev = input_dev;

        err = snd_device_new(codec->card, SNDRV_DEV_JACK, beep, &ops);
        if (err < 0)
                goto err_input;

        return 0;

 err_input:
        input_free_device(beep->dev);
 err_free:
        kfree(beep);
        codec->beep = NULL;
        return err;
}
EXPORT_SYMBOL_GPL(snd_hda_attach_beep_device);

/**
 * snd_hda_detach_beep_device - Detach the beep device
 * @codec: the HDA codec
 */
void snd_hda_detach_beep_device(struct hda_codec *codec)
{
        if (!codec->bus->shutdown && codec->beep)
                snd_device_free(codec->card, codec->beep);
}
EXPORT_SYMBOL_GPL(snd_hda_detach_beep_device);

static bool ctl_has_mute(struct snd_kcontrol *kcontrol)
{
        struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
        return query_amp_caps(codec, get_amp_nid(kcontrol),
                              get_amp_direction(kcontrol)) & AC_AMPCAP_MUTE;
}

/* get/put callbacks for beep mute mixer switches */

/**
 * snd_hda_mixer_amp_switch_get_beep - Get callback for beep controls
 * @kcontrol: ctl element
 * @ucontrol: pointer to get/store the data
 */
int snd_hda_mixer_amp_switch_get_beep(struct snd_kcontrol *kcontrol,
                                      struct snd_ctl_elem_value *ucontrol)
{
        struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
        struct hda_beep *beep = codec->beep;
        if (beep && (!beep->enabled || !ctl_has_mute(kcontrol))) {
                ucontrol->value.integer.value[0] =
                        ucontrol->value.integer.value[1] = beep->enabled;
                return 0;
        }
        return snd_hda_mixer_amp_switch_get(kcontrol, ucontrol);
}
EXPORT_SYMBOL_GPL(snd_hda_mixer_amp_switch_get_beep);

/**
 * snd_hda_mixer_amp_switch_put_beep - Put callback for beep controls
 * @kcontrol: ctl element
 * @ucontrol: pointer to get/store the data
 */
int snd_hda_mixer_amp_switch_put_beep(struct snd_kcontrol *kcontrol,
                                      struct snd_ctl_elem_value *ucontrol)
{
        struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
        struct hda_beep *beep = codec->beep;
        if (beep) {
                u8 chs = get_amp_channels(kcontrol);
                int enable = 0;
                long *valp = ucontrol->value.integer.value;
                if (chs & 1) {
                        enable |= *valp;
                        valp++;
                }
                if (chs & 2)
                        enable |= *valp;
                snd_hda_enable_beep_device(codec, enable);
        }
        if (!ctl_has_mute(kcontrol))
                return 0;
        return snd_hda_mixer_amp_switch_put(kcontrol, ucontrol);
}
EXPORT_SYMBOL_GPL(snd_hda_mixer_amp_switch_put_beep);