// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Jack abstraction layer
 *
 *  Copyright 2008 Wolfson Microelectronics
 */

#include <linux/input.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/mm.h>
#include <linux/debugfs.h>
#include <sound/jack.h>
#include <sound/core.h>
#include <sound/control.h>

struct snd_jack_kctl {
        struct snd_kcontrol *kctl;
        struct list_head list;  /* list of controls belong to the same jack */
        unsigned int mask_bits; /* only masked status bits are reported via kctl */
        struct snd_jack *jack;  /* pointer to struct snd_jack */
        bool sw_inject_enable;  /* allow to inject plug event via debugfs */
#ifdef CONFIG_SND_JACK_INJECTION_DEBUG
        struct dentry *jack_debugfs_root; /* jack_kctl debugfs root */
#endif
};

#ifdef CONFIG_SND_JACK_INPUT_DEV
static const int jack_switch_types[SND_JACK_SWITCH_TYPES] = {
        SW_HEADPHONE_INSERT,
        SW_MICROPHONE_INSERT,
        SW_LINEOUT_INSERT,
        SW_JACK_PHYSICAL_INSERT,
        SW_VIDEOOUT_INSERT,
        SW_LINEIN_INSERT,
        SW_USB_INSERT,
};
#endif /* CONFIG_SND_JACK_INPUT_DEV */

static void snd_jack_remove_debugfs(struct snd_jack *jack);

static int snd_jack_dev_disconnect(struct snd_device *device)
{
        struct snd_jack *jack = device->device_data;

        snd_jack_remove_debugfs(jack);

#ifdef CONFIG_SND_JACK_INPUT_DEV
        guard(mutex)(&jack->input_dev_lock);
        if (!jack->input_dev)
                return 0;

        /* If the input device is registered with the input subsystem
         * then we need to use a different deallocator. */
        if (jack->registered)
                input_unregister_device(jack->input_dev);
        else
                input_free_device(jack->input_dev);
        jack->input_dev = NULL;
#endif /* CONFIG_SND_JACK_INPUT_DEV */
        return 0;
}

static int snd_jack_dev_free(struct snd_device *device)
{
        struct snd_jack *jack = device->device_data;
        struct snd_card *card = device->card;
        struct snd_jack_kctl *jack_kctl, *tmp_jack_kctl;

        list_for_each_entry_safe(jack_kctl, tmp_jack_kctl, &jack->kctl_list, list) {
                list_del_init(&jack_kctl->list);
                snd_ctl_remove(card, jack_kctl->kctl);
        }

        if (jack->private_free)
                jack->private_free(jack);

        snd_jack_dev_disconnect(device);

        kfree(jack->id);
        kfree(jack);

        return 0;
}

#ifdef CONFIG_SND_JACK_INPUT_DEV
static int snd_jack_dev_register(struct snd_device *device)
{
        struct snd_jack *jack = device->device_data;
        struct snd_card *card = device->card;
        int err, i;

        snprintf(jack->name, sizeof(jack->name), "%s %s",
                 card->shortname, jack->id);

        guard(mutex)(&jack->input_dev_lock);
        if (!jack->input_dev)
                return 0;

        jack->input_dev->name = jack->name;

        /* Default to the sound card device. */
        if (!jack->input_dev->dev.parent)
                jack->input_dev->dev.parent = snd_card_get_device_link(card);

        /* Add capabilities for any keys that are enabled */
        for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
                int testbit = SND_JACK_BTN_0 >> i;

                if (!(jack->type & testbit))
                        continue;

                if (!jack->key[i])
                        jack->key[i] = BTN_0 + i;

                input_set_capability(jack->input_dev, EV_KEY, jack->key[i]);
        }

        err = input_register_device(jack->input_dev);
        if (err == 0)
                jack->registered = 1;

        return err;
}
#endif /* CONFIG_SND_JACK_INPUT_DEV */

#ifdef CONFIG_SND_JACK_INJECTION_DEBUG
static void snd_jack_inject_report(struct snd_jack_kctl *jack_kctl, int status)
{
        struct snd_jack *jack;
#ifdef CONFIG_SND_JACK_INPUT_DEV
        int i;
#endif
        if (!jack_kctl)
                return;

        jack = jack_kctl->jack;

        if (jack_kctl->sw_inject_enable)
                snd_kctl_jack_report(jack->card, jack_kctl->kctl,
                                     status & jack_kctl->mask_bits);

#ifdef CONFIG_SND_JACK_INPUT_DEV
        if (!jack->input_dev)
                return;

        for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
                int testbit = ((SND_JACK_BTN_0 >> i) & jack_kctl->mask_bits);

                if (jack->type & testbit)
                        input_report_key(jack->input_dev, jack->key[i],
                                         status & testbit);
        }

        for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
                int testbit = ((1 << i) & jack_kctl->mask_bits);

                if (jack->type & testbit)
                        input_report_switch(jack->input_dev,
                                            jack_switch_types[i],
                                            status & testbit);
        }

        input_sync(jack->input_dev);
#endif /* CONFIG_SND_JACK_INPUT_DEV */
}

static ssize_t sw_inject_enable_read(struct file *file,
                                     char __user *to, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        int len, ret;
        char buf[128];

        len = scnprintf(buf, sizeof(buf), "%s: %s\t\t%s: %i\n", "Jack", jack_kctl->kctl->id.name,
                        "Inject Enabled", jack_kctl->sw_inject_enable);
        ret = simple_read_from_buffer(to, count, ppos, buf, len);

        return ret;
}

static ssize_t sw_inject_enable_write(struct file *file,
                                      const char __user *from, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        int ret, err;
        unsigned long enable;
        char buf[8] = { 0 };

        ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, from, count);
        err = kstrtoul(buf, 0, &enable);
        if (err)
                return err;

        if (jack_kctl->sw_inject_enable == (!!enable))
                return ret;

        jack_kctl->sw_inject_enable = !!enable;

        if (!jack_kctl->sw_inject_enable)
                snd_jack_report(jack_kctl->jack, jack_kctl->jack->hw_status_cache);

        return ret;
}

static ssize_t jackin_inject_write(struct file *file,
                                   const char __user *from, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        int ret, err;
        unsigned long enable;
        char buf[8] = { 0 };

        if (!jack_kctl->sw_inject_enable)
                return -EINVAL;

        ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, from, count);
        err = kstrtoul(buf, 0, &enable);
        if (err)
                return err;

        snd_jack_inject_report(jack_kctl, !!enable ? jack_kctl->mask_bits : 0);

        return ret;
}

static ssize_t jack_kctl_id_read(struct file *file,
                                 char __user *to, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        char buf[64];
        int len, ret;

        len = scnprintf(buf, sizeof(buf), "%s\n", jack_kctl->kctl->id.name);
        ret = simple_read_from_buffer(to, count, ppos, buf, len);

        return ret;
}

/* the bit definition is aligned with snd_jack_types in jack.h */
static const char * const jack_events_name[] = {
        "HEADPHONE(0x0001)", "MICROPHONE(0x0002)", "LINEOUT(0x0004)",
        "MECHANICAL(0x0008)", "VIDEOOUT(0x0010)", "LINEIN(0x0020)",
        "USB(0x0040)", "", "", "BTN_5(0x0200)", "BTN_4(0x0400)",
        "BTN_3(0x0800)", "BTN_2(0x1000)", "BTN_1(0x2000)", "BTN_0(0x4000)",
        "",
};

/* the recommended buffer size is 256 */
static int parse_mask_bits(unsigned int mask_bits, char *buf, size_t buf_size)
{
        int i;

        scnprintf(buf, buf_size, "0x%04x", mask_bits);

        for (i = 0; i < ARRAY_SIZE(jack_events_name); i++)
                if (mask_bits & (1 << i)) {
                        strlcat(buf, " ", buf_size);
                        strlcat(buf, jack_events_name[i], buf_size);
                }
        strlcat(buf, "\n", buf_size);

        return strlen(buf);
}

static ssize_t jack_kctl_mask_bits_read(struct file *file,
                                        char __user *to, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        char buf[256];
        int len, ret;

        len = parse_mask_bits(jack_kctl->mask_bits, buf, sizeof(buf));
        ret = simple_read_from_buffer(to, count, ppos, buf, len);

        return ret;
}

static ssize_t jack_kctl_status_read(struct file *file,
                                     char __user *to, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        char buf[16];
        int len, ret;

        len = scnprintf(buf, sizeof(buf), "%s\n", jack_kctl->kctl->private_value ?
                        "Plugged" : "Unplugged");
        ret = simple_read_from_buffer(to, count, ppos, buf, len);

        return ret;
}

#ifdef CONFIG_SND_JACK_INPUT_DEV
static ssize_t jack_type_read(struct file *file,
                              char __user *to, size_t count, loff_t *ppos)
{
        struct snd_jack_kctl *jack_kctl = file->private_data;
        char buf[256];
        int len, ret;

        len = parse_mask_bits(jack_kctl->jack->type, buf, sizeof(buf));
        ret = simple_read_from_buffer(to, count, ppos, buf, len);

        return ret;
}

static const struct file_operations jack_type_fops = {
        .open = simple_open,
        .read = jack_type_read,
        .llseek = default_llseek,
};
#endif

static const struct file_operations sw_inject_enable_fops = {
        .open = simple_open,
        .read = sw_inject_enable_read,
        .write = sw_inject_enable_write,
        .llseek = default_llseek,
};

static const struct file_operations jackin_inject_fops = {
        .open = simple_open,
        .write = jackin_inject_write,
        .llseek = default_llseek,
};

static const struct file_operations jack_kctl_id_fops = {
        .open = simple_open,
        .read = jack_kctl_id_read,
        .llseek = default_llseek,
};

static const struct file_operations jack_kctl_mask_bits_fops = {
        .open = simple_open,
        .read = jack_kctl_mask_bits_read,
        .llseek = default_llseek,
};

static const struct file_operations jack_kctl_status_fops = {
        .open = simple_open,
        .read = jack_kctl_status_read,
        .llseek = default_llseek,
};

static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
                                            struct snd_jack_kctl *jack_kctl)
{
        char *tname;
        int i;

        /* Don't create injection interface for Phantom jacks */
        if (strstr(jack_kctl->kctl->id.name, "Phantom"))
                return 0;

        tname = kstrdup(jack_kctl->kctl->id.name, GFP_KERNEL);
        if (!tname)
                return -ENOMEM;

        /* replace the chars which are not suitable for folder's name with _ */
        for (i = 0; tname[i]; i++)
                if (!isalnum(tname[i]))
                        tname[i] = '_';

        jack_kctl->jack_debugfs_root = debugfs_create_dir(tname, jack->card->debugfs_root);
        kfree(tname);

        debugfs_create_file("sw_inject_enable", 0644, jack_kctl->jack_debugfs_root, jack_kctl,
                            &sw_inject_enable_fops);

        debugfs_create_file("jackin_inject", 0200, jack_kctl->jack_debugfs_root, jack_kctl,
                            &jackin_inject_fops);

        debugfs_create_file("kctl_id", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
                            &jack_kctl_id_fops);

        debugfs_create_file("mask_bits", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
                            &jack_kctl_mask_bits_fops);

        debugfs_create_file("status", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
                            &jack_kctl_status_fops);

#ifdef CONFIG_SND_JACK_INPUT_DEV
        debugfs_create_file("type", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
                            &jack_type_fops);
#endif
        return 0;
}

static void snd_jack_remove_debugfs(struct snd_jack *jack)
{
        struct snd_jack_kctl *jack_kctl;

        list_for_each_entry(jack_kctl, &jack->kctl_list, list) {
                debugfs_remove(jack_kctl->jack_debugfs_root);
                jack_kctl->jack_debugfs_root = NULL;
        }
}
#else /* CONFIG_SND_JACK_INJECTION_DEBUG */
static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
                                            struct snd_jack_kctl *jack_kctl)
{
        return 0;
}

static void snd_jack_remove_debugfs(struct snd_jack *jack)
{
}
#endif /* CONFIG_SND_JACK_INJECTION_DEBUG */

static void snd_jack_kctl_private_free(struct snd_kcontrol *kctl)
{
        struct snd_jack_kctl *jack_kctl;

        jack_kctl = kctl->private_data;
        if (jack_kctl) {
                list_del(&jack_kctl->list);
                kfree(jack_kctl);
        }
}

static void snd_jack_kctl_add(struct snd_jack *jack, struct snd_jack_kctl *jack_kctl)
{
        jack_kctl->jack = jack;
        list_add_tail(&jack_kctl->list, &jack->kctl_list);
        snd_jack_debugfs_add_inject_node(jack, jack_kctl);
}

static struct snd_jack_kctl * snd_jack_kctl_new(struct snd_card *card, const char *name, unsigned int mask)
{
        struct snd_kcontrol *kctl;
        struct snd_jack_kctl *jack_kctl;
        int err;

        kctl = snd_kctl_jack_new(name, card);
        if (!kctl)
                return NULL;

        err = snd_ctl_add(card, kctl);
        if (err < 0)
                return NULL;

        jack_kctl = kzalloc_obj(*jack_kctl);

        if (!jack_kctl)
                goto error;

        jack_kctl->kctl = kctl;
        jack_kctl->mask_bits = mask;

        kctl->private_data = jack_kctl;
        kctl->private_free = snd_jack_kctl_private_free;

        return jack_kctl;
error:
        snd_ctl_free_one(kctl);
        return NULL;
}

/**
 * snd_jack_add_new_kctl - Create a new snd_jack_kctl and add it to jack
 * @jack:  the jack instance which the kctl will attaching to
 * @name:  the name for the snd_kcontrol object
 * @mask:  a bitmask of enum snd_jack_type values that can be detected
 *         by this snd_jack_kctl object.
 *
 * Creates a new snd_kcontrol object and adds it to the jack kctl_list.
 *
 * Return: Zero if successful, or a negative error code on failure.
 */
int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name, int mask)
{
        struct snd_jack_kctl *jack_kctl;

        jack_kctl = snd_jack_kctl_new(jack->card, name, mask);
        if (!jack_kctl)
                return -ENOMEM;

        snd_jack_kctl_add(jack, jack_kctl);
        return 0;
}
EXPORT_SYMBOL(snd_jack_add_new_kctl);

/**
 * snd_jack_new - Create a new jack
 * @card:  the card instance
 * @id:    an identifying string for this jack
 * @type:  a bitmask of enum snd_jack_type values that can be detected by
 *         this jack
 * @jjack: Used to provide the allocated jack object to the caller.
 * @initial_kctl: if true, create a kcontrol and add it to the jack list.
 * @phantom_jack: Don't create a input device for phantom jacks.
 *
 * Creates a new jack object.
 *
 * Return: Zero if successful, or a negative error code on failure.
 * On success @jjack will be initialised.
 */
int snd_jack_new(struct snd_card *card, const char *id, int type,
                 struct snd_jack **jjack, bool initial_kctl, bool phantom_jack)
{
        struct snd_jack *jack;
        struct snd_jack_kctl *jack_kctl = NULL;
        int err;
        static const struct snd_device_ops ops = {
                .dev_free = snd_jack_dev_free,
#ifdef CONFIG_SND_JACK_INPUT_DEV
                .dev_register = snd_jack_dev_register,
#endif /* CONFIG_SND_JACK_INPUT_DEV */
                .dev_disconnect = snd_jack_dev_disconnect,
        };

        if (initial_kctl) {
                jack_kctl = snd_jack_kctl_new(card, id, type);
                if (!jack_kctl)
                        return -ENOMEM;
        }

        jack = kzalloc_obj(struct snd_jack);
        if (jack == NULL)
                return -ENOMEM;

        jack->id = kstrdup(id, GFP_KERNEL);
        if (jack->id == NULL) {
                kfree(jack);
                return -ENOMEM;
        }

#ifdef CONFIG_SND_JACK_INPUT_DEV
        mutex_init(&jack->input_dev_lock);

        /* don't create input device for phantom jack */
        if (!phantom_jack) {
                int i;

                jack->input_dev = input_allocate_device();
                if (jack->input_dev == NULL) {
                        err = -ENOMEM;
                        goto fail_input;
                }

                jack->input_dev->phys = "ALSA";

                jack->type = type;

                for (i = 0; i < SND_JACK_SWITCH_TYPES; i++)
                        if (type & (1 << i))
                                input_set_capability(jack->input_dev, EV_SW,
                                                     jack_switch_types[i]);

        }
#endif /* CONFIG_SND_JACK_INPUT_DEV */

        err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
        if (err < 0)
                goto fail_input;

        jack->card = card;
        INIT_LIST_HEAD(&jack->kctl_list);

        if (initial_kctl)
                snd_jack_kctl_add(jack, jack_kctl);

        *jjack = jack;

        return 0;

fail_input:
#ifdef CONFIG_SND_JACK_INPUT_DEV
        input_free_device(jack->input_dev);
#endif
        kfree(jack->id);
        kfree(jack);
        return err;
}
EXPORT_SYMBOL(snd_jack_new);

#ifdef CONFIG_SND_JACK_INPUT_DEV
/**
 * snd_jack_set_key - Set a key mapping on a jack
 *
 * @jack:    The jack to configure
 * @type:    Jack report type for this key
 * @keytype: Input layer key type to be reported
 *
 * Map a SND_JACK_BTN_* button type to an input layer key, allowing
 * reporting of keys on accessories via the jack abstraction.  If no
 * mapping is provided but keys are enabled in the jack type then
 * BTN_n numeric buttons will be reported.
 *
 * If jacks are not reporting via the input API this call will have no
 * effect.
 *
 * Note that this is intended to be use by simple devices with small
 * numbers of keys that can be reported.  It is also possible to
 * access the input device directly - devices with complex input
 * capabilities on accessories should consider doing this rather than
 * using this abstraction.
 *
 * This function may only be called prior to registration of the jack.
 *
 * Return: Zero if successful, or a negative error code on failure.
 */
int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
                     int keytype)
{
        int key = fls(SND_JACK_BTN_0) - fls(type);

        WARN_ON(jack->registered);

        if (!keytype || key >= ARRAY_SIZE(jack->key))
                return -EINVAL;

        jack->type |= type;
        jack->key[key] = keytype;
        return 0;
}
EXPORT_SYMBOL(snd_jack_set_key);
#endif /* CONFIG_SND_JACK_INPUT_DEV */

/**
 * snd_jack_report - Report the current status of a jack
 * Note: This function uses mutexes and should be called from a
 * context which can sleep (such as a workqueue).
 *
 * @jack:   The jack to report status for
 * @status: The current status of the jack
 */
void snd_jack_report(struct snd_jack *jack, int status)
{
        struct snd_jack_kctl *jack_kctl;
        unsigned int mask_bits = 0;
#ifdef CONFIG_SND_JACK_INPUT_DEV
        struct input_dev *idev;
        int i;
#endif

        if (!jack)
                return;

        jack->hw_status_cache = status;

        list_for_each_entry(jack_kctl, &jack->kctl_list, list)
                if (jack_kctl->sw_inject_enable)
                        mask_bits |= jack_kctl->mask_bits;
                else
                        snd_kctl_jack_report(jack->card, jack_kctl->kctl,
                                             status & jack_kctl->mask_bits);

#ifdef CONFIG_SND_JACK_INPUT_DEV
        idev = input_get_device(jack->input_dev);
        if (!idev)
                return;

        for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
                int testbit = ((SND_JACK_BTN_0 >> i) & ~mask_bits);

                if (jack->type & testbit)
                        input_report_key(idev, jack->key[i],
                                         status & testbit);
        }

        for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
                int testbit = ((1 << i) & ~mask_bits);

                if (jack->type & testbit)
                        input_report_switch(idev,
                                            jack_switch_types[i],
                                            status & testbit);
        }

        input_sync(idev);
        input_put_device(idev);
#endif /* CONFIG_SND_JACK_INPUT_DEV */
}
EXPORT_SYMBOL(snd_jack_report);