// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Helper functions for jack-detection kcontrols
 *
 * Copyright (c) 2011 Takashi Iwai <tiwai@suse.de>
 */

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/string.h>
#include <sound/core.h>
#include <sound/control.h>

#define jack_detect_kctl_info   snd_ctl_boolean_mono_info

static int jack_detect_kctl_get(struct snd_kcontrol *kcontrol,
                                struct snd_ctl_elem_value *ucontrol)
{
        ucontrol->value.integer.value[0] = kcontrol->private_value;
        return 0;
}

static const struct snd_kcontrol_new jack_detect_kctl = {
        /* name is filled later */
        .iface = SNDRV_CTL_ELEM_IFACE_CARD,
        .access = SNDRV_CTL_ELEM_ACCESS_READ,
        .info = jack_detect_kctl_info,
        .get = jack_detect_kctl_get,
};

static int get_available_index(struct snd_card *card, const char *name)
{
        struct snd_ctl_elem_id sid;

        memset(&sid, 0, sizeof(sid));

        sid.index = 0;
        sid.iface = SNDRV_CTL_ELEM_IFACE_CARD;
        strscpy(sid.name, name, sizeof(sid.name));

        while (snd_ctl_find_id(card, &sid)) {
                sid.index++;
                /* reset numid; otherwise snd_ctl_find_id() hits this again */
                sid.numid = 0;
        }

        return sid.index;
}

static void jack_kctl_name_gen(char *name, const char *src_name, size_t size)
{
        size_t count = strlen(src_name);
        const char *suf = " Jack";
        size_t suf_len = strlen(suf);
        bool append_suf = true;

        if (count >= suf_len)
                append_suf = strncmp(&src_name[count - suf_len], suf, suf_len) != 0;

        if (append_suf)
                snprintf(name, size, "%s%s", src_name, suf);
        else
                strscpy(name, src_name, size);
}

struct snd_kcontrol *
snd_kctl_jack_new(const char *name, struct snd_card *card)
{
        struct snd_kcontrol *kctl;

        kctl = snd_ctl_new1(&jack_detect_kctl, NULL);
        if (!kctl)
                return NULL;

        jack_kctl_name_gen(kctl->id.name, name, sizeof(kctl->id.name));
        kctl->id.index = get_available_index(card, kctl->id.name);
        kctl->private_value = 0;
        return kctl;
}

void snd_kctl_jack_report(struct snd_card *card,
                          struct snd_kcontrol *kctl, bool status)
{
        if (kctl->private_value == status)
                return;
        kctl->private_value = status;
        snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, &kctl->id);
}