// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *   ALSA driver for TEA5757/5759 Philips AM/FM radio tuner chips
 *
 *      Copyright (c) 2004 Jaroslav Kysela <perex@perex.cz>
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <asm/io.h>
#include <media/v4l2-device.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include <media/drv-intf/tea575x.h>

MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("Routines for control of TEA5757/5759 Philips AM/FM radio tuner chips");
MODULE_LICENSE("GPL");

/*
 * definitions
 */

#define TEA575X_BIT_SEARCH      (1<<24)         /* 1 = search action, 0 = tuned */
#define TEA575X_BIT_UPDOWN      (1<<23)         /* 0 = search down, 1 = search up */
#define TEA575X_BIT_MONO        (1<<22)         /* 0 = stereo, 1 = mono */
#define TEA575X_BIT_BAND_MASK   (3<<20)
#define TEA575X_BIT_BAND_FM     (0<<20)
#define TEA575X_BIT_BAND_MW     (1<<20)
#define TEA575X_BIT_BAND_LW     (2<<20)
#define TEA575X_BIT_BAND_SW     (3<<20)
#define TEA575X_BIT_PORT_0      (1<<19)         /* user bit */
#define TEA575X_BIT_PORT_1      (1<<18)         /* user bit */
#define TEA575X_BIT_SEARCH_MASK (3<<16)         /* search level */
#define TEA575X_BIT_SEARCH_5_28      (0<<16)    /* FM >5uV, AM >28uV */
#define TEA575X_BIT_SEARCH_10_40     (1<<16)    /* FM >10uV, AM > 40uV */
#define TEA575X_BIT_SEARCH_30_63     (2<<16)    /* FM >30uV, AM > 63uV */
#define TEA575X_BIT_SEARCH_150_1000  (3<<16)    /* FM > 150uV, AM > 1000uV */
#define TEA575X_BIT_DUMMY       (1<<15)         /* buffer */
#define TEA575X_BIT_FREQ_MASK   0x7fff

enum { BAND_FM, BAND_FM_JAPAN, BAND_AM };

static const struct v4l2_frequency_band bands[] = {
        {
                .type = V4L2_TUNER_RADIO,
                .index = 0,
                .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
                              V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =  87500 * 16,
                .rangehigh  = 108000 * 16,
                .modulation = V4L2_BAND_MODULATION_FM,
        },
        {
                .type = V4L2_TUNER_RADIO,
                .index = 0,
                .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
                              V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   = 76000 * 16,
                .rangehigh  = 91000 * 16,
                .modulation = V4L2_BAND_MODULATION_FM,
        },
        {
                .type = V4L2_TUNER_RADIO,
                .index = 1,
                .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS,
                .rangelow   =  530 * 16,
                .rangehigh  = 1710 * 16,
                .modulation = V4L2_BAND_MODULATION_AM,
        },
};

/*
 * lowlevel part
 */

static void snd_tea575x_write(struct snd_tea575x *tea, unsigned int val)
{
        u16 l;
        u8 data;

        if (tea->ops->write_val)
                return tea->ops->write_val(tea, val);

        tea->ops->set_direction(tea, 1);
        udelay(16);

        for (l = 25; l > 0; l--) {
                data = (val >> 24) & TEA575X_DATA;
                val <<= 1;                      /* shift data */
                tea->ops->set_pins(tea, data | TEA575X_WREN);
                udelay(2);
                tea->ops->set_pins(tea, data | TEA575X_WREN | TEA575X_CLK);
                udelay(2);
                tea->ops->set_pins(tea, data | TEA575X_WREN);
                udelay(2);
        }

        if (!tea->mute)
                tea->ops->set_pins(tea, 0);
}

static u32 snd_tea575x_read(struct snd_tea575x *tea)
{
        u16 l, rdata;
        u32 data = 0;

        if (tea->ops->read_val)
                return tea->ops->read_val(tea);

        tea->ops->set_direction(tea, 0);
        tea->ops->set_pins(tea, 0);
        udelay(16);

        for (l = 24; l--;) {
                tea->ops->set_pins(tea, TEA575X_CLK);
                udelay(2);
                if (!l)
                        tea->tuned = tea->ops->get_pins(tea) & TEA575X_MOST ? 0 : 1;
                tea->ops->set_pins(tea, 0);
                udelay(2);
                data <<= 1;                     /* shift data */
                rdata = tea->ops->get_pins(tea);
                if (!l)
                        tea->stereo = (rdata & TEA575X_MOST) ?  0 : 1;
                if (rdata & TEA575X_DATA)
                        data++;
                udelay(2);
        }

        if (tea->mute)
                tea->ops->set_pins(tea, TEA575X_WREN);

        return data;
}

static u32 snd_tea575x_val_to_freq(struct snd_tea575x *tea, u32 val)
{
        u32 freq = val & TEA575X_BIT_FREQ_MASK;

        if (freq == 0)
                return freq;

        switch (tea->band) {
        case BAND_FM:
                /* freq *= 12.5 */
                freq *= 125;
                freq /= 10;
                /* crystal fixup */
                freq -= TEA575X_FMIF;
                break;
        case BAND_FM_JAPAN:
                /* freq *= 12.5 */
                freq *= 125;
                freq /= 10;
                /* crystal fixup */
                freq += TEA575X_FMIF;
                break;
        case BAND_AM:
                /* crystal fixup */
                freq -= TEA575X_AMIF;
                break;
        }

        return clamp(freq * 16, bands[tea->band].rangelow,
                                bands[tea->band].rangehigh); /* from kHz */
}

static u32 snd_tea575x_get_freq(struct snd_tea575x *tea)
{
        return snd_tea575x_val_to_freq(tea, snd_tea575x_read(tea));
}

void snd_tea575x_set_freq(struct snd_tea575x *tea)
{
        u32 freq = tea->freq / 16;      /* to kHz */
        u32 band = 0;

        switch (tea->band) {
        case BAND_FM:
                band = TEA575X_BIT_BAND_FM;
                /* crystal fixup */
                freq += TEA575X_FMIF;
                /* freq /= 12.5 */
                freq *= 10;
                freq /= 125;
                break;
        case BAND_FM_JAPAN:
                band = TEA575X_BIT_BAND_FM;
                /* crystal fixup */
                freq -= TEA575X_FMIF;
                /* freq /= 12.5 */
                freq *= 10;
                freq /= 125;
                break;
        case BAND_AM:
                band = TEA575X_BIT_BAND_MW;
                /* crystal fixup */
                freq += TEA575X_AMIF;
                break;
        }

        tea->val &= ~(TEA575X_BIT_FREQ_MASK | TEA575X_BIT_BAND_MASK);
        tea->val |= band;
        tea->val |= freq & TEA575X_BIT_FREQ_MASK;
        snd_tea575x_write(tea, tea->val);
        tea->freq = snd_tea575x_val_to_freq(tea, tea->val);
}
EXPORT_SYMBOL(snd_tea575x_set_freq);

/*
 * Linux Video interface
 */

static int vidioc_querycap(struct file *file, void  *priv,
                                        struct v4l2_capability *v)
{
        struct snd_tea575x *tea = video_drvdata(file);

        strscpy(v->driver, tea->v4l2_dev->name, sizeof(v->driver));
        strscpy(v->card, tea->card, sizeof(v->card));
        strlcat(v->card, tea->tea5759 ? " TEA5759" : " TEA5757", sizeof(v->card));
        strscpy(v->bus_info, tea->bus_info, sizeof(v->bus_info));
        return 0;
}

int snd_tea575x_enum_freq_bands(struct snd_tea575x *tea,
                                        struct v4l2_frequency_band *band)
{
        int index;

        if (band->tuner != 0)
                return -EINVAL;

        switch (band->index) {
        case 0:
                if (tea->tea5759)
                        index = BAND_FM_JAPAN;
                else
                        index = BAND_FM;
                break;
        case 1:
                if (tea->has_am) {
                        index = BAND_AM;
                        break;
                }
                fallthrough;
        default:
                return -EINVAL;
        }

        *band = bands[index];
        if (!tea->cannot_read_data)
                band->capability |= V4L2_TUNER_CAP_HWSEEK_BOUNDED;

        return 0;
}
EXPORT_SYMBOL(snd_tea575x_enum_freq_bands);

static int vidioc_enum_freq_bands(struct file *file, void *priv,
                                         struct v4l2_frequency_band *band)
{
        struct snd_tea575x *tea = video_drvdata(file);

        return snd_tea575x_enum_freq_bands(tea, band);
}

int snd_tea575x_g_tuner(struct snd_tea575x *tea, struct v4l2_tuner *v)
{
        struct v4l2_frequency_band band_fm = { 0, };

        if (v->index > 0)
                return -EINVAL;

        snd_tea575x_read(tea);
        snd_tea575x_enum_freq_bands(tea, &band_fm);

        memset(v, 0, sizeof(*v));
        strscpy(v->name, tea->has_am ? "FM/AM" : "FM", sizeof(v->name));
        v->type = V4L2_TUNER_RADIO;
        v->capability = band_fm.capability;
        v->rangelow = tea->has_am ? bands[BAND_AM].rangelow : band_fm.rangelow;
        v->rangehigh = band_fm.rangehigh;
        v->rxsubchans = tea->stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
        v->audmode = (tea->val & TEA575X_BIT_MONO) ?
                V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO;
        v->signal = tea->tuned ? 0xffff : 0;
        return 0;
}
EXPORT_SYMBOL(snd_tea575x_g_tuner);

static int vidioc_g_tuner(struct file *file, void *priv,
                                        struct v4l2_tuner *v)
{
        struct snd_tea575x *tea = video_drvdata(file);

        return snd_tea575x_g_tuner(tea, v);
}

static int vidioc_s_tuner(struct file *file, void *priv,
                                        const struct v4l2_tuner *v)
{
        struct snd_tea575x *tea = video_drvdata(file);
        u32 orig_val = tea->val;

        if (v->index)
                return -EINVAL;
        tea->val &= ~TEA575X_BIT_MONO;
        if (v->audmode == V4L2_TUNER_MODE_MONO)
                tea->val |= TEA575X_BIT_MONO;
        /* Only apply changes if currently tuning FM */
        if (tea->band != BAND_AM && tea->val != orig_val)
                snd_tea575x_set_freq(tea);

        return 0;
}

static int vidioc_g_frequency(struct file *file, void *priv,
                                        struct v4l2_frequency *f)
{
        struct snd_tea575x *tea = video_drvdata(file);

        if (f->tuner != 0)
                return -EINVAL;
        f->type = V4L2_TUNER_RADIO;
        f->frequency = tea->freq;
        return 0;
}

static int vidioc_s_frequency(struct file *file, void *priv,
                                        const struct v4l2_frequency *f)
{
        struct snd_tea575x *tea = video_drvdata(file);

        if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
                return -EINVAL;

        if (tea->has_am && f->frequency < (20000 * 16))
                tea->band = BAND_AM;
        else if (tea->tea5759)
                tea->band = BAND_FM_JAPAN;
        else
                tea->band = BAND_FM;

        tea->freq = clamp_t(u32, f->frequency, bands[tea->band].rangelow,
                                        bands[tea->band].rangehigh);
        snd_tea575x_set_freq(tea);
        return 0;
}

int snd_tea575x_s_hw_freq_seek(struct file *file, struct snd_tea575x *tea,
                                const struct v4l2_hw_freq_seek *a)
{
        unsigned long timeout;
        int i, spacing;

        if (tea->cannot_read_data)
                return -ENOTTY;
        if (a->tuner || a->wrap_around)
                return -EINVAL;

        if (file->f_flags & O_NONBLOCK)
                return -EWOULDBLOCK;

        if (a->rangelow || a->rangehigh) {
                for (i = 0; i < ARRAY_SIZE(bands); i++) {
                        if ((i == BAND_FM && tea->tea5759) ||
                            (i == BAND_FM_JAPAN && !tea->tea5759) ||
                            (i == BAND_AM && !tea->has_am))
                                continue;
                        if (bands[i].rangelow  == a->rangelow &&
                            bands[i].rangehigh == a->rangehigh)
                                break;
                }
                if (i == ARRAY_SIZE(bands))
                        return -EINVAL; /* No matching band found */
                if (i != tea->band) {
                        tea->band = i;
                        tea->freq = clamp(tea->freq, bands[i].rangelow,
                                                     bands[i].rangehigh);
                        snd_tea575x_set_freq(tea);
                }
        }

        spacing = (tea->band == BAND_AM) ? 5 : 50; /* kHz */

        /* clear the frequency, HW will fill it in */
        tea->val &= ~TEA575X_BIT_FREQ_MASK;
        tea->val |= TEA575X_BIT_SEARCH;
        if (a->seek_upward)
                tea->val |= TEA575X_BIT_UPDOWN;
        else
                tea->val &= ~TEA575X_BIT_UPDOWN;
        snd_tea575x_write(tea, tea->val);
        timeout = jiffies + msecs_to_jiffies(10000);
        for (;;) {
                if (time_after(jiffies, timeout))
                        break;
                if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
                        /* some signal arrived, stop search */
                        tea->val &= ~TEA575X_BIT_SEARCH;
                        snd_tea575x_set_freq(tea);
                        return -ERESTARTSYS;
                }
                if (!(snd_tea575x_read(tea) & TEA575X_BIT_SEARCH)) {
                        u32 freq;

                        /* Found a frequency, wait until it can be read */
                        for (i = 0; i < 100; i++) {
                                msleep(10);
                                freq = snd_tea575x_get_freq(tea);
                                if (freq) /* available */
                                        break;
                        }
                        if (freq == 0) /* shouldn't happen */
                                break;
                        /*
                         * if we moved by less than the spacing, or in the
                         * wrong direction, continue seeking
                         */
                        if (abs(tea->freq - freq) < 16 * spacing ||
                                        (a->seek_upward && freq < tea->freq) ||
                                        (!a->seek_upward && freq > tea->freq)) {
                                snd_tea575x_write(tea, tea->val);
                                continue;
                        }
                        tea->freq = freq;
                        tea->val &= ~TEA575X_BIT_SEARCH;
                        return 0;
                }
        }
        tea->val &= ~TEA575X_BIT_SEARCH;
        snd_tea575x_set_freq(tea);
        return -ENODATA;
}
EXPORT_SYMBOL(snd_tea575x_s_hw_freq_seek);

static int vidioc_s_hw_freq_seek(struct file *file, void *fh,
                                        const struct v4l2_hw_freq_seek *a)
{
        struct snd_tea575x *tea = video_drvdata(file);

        return snd_tea575x_s_hw_freq_seek(file, tea, a);
}

static int tea575x_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct snd_tea575x *tea = container_of(ctrl->handler, struct snd_tea575x, ctrl_handler);

        switch (ctrl->id) {
        case V4L2_CID_AUDIO_MUTE:
                tea->mute = ctrl->val;
                snd_tea575x_set_freq(tea);
                return 0;
        }

        return -EINVAL;
}

static const struct v4l2_file_operations tea575x_fops = {
        .unlocked_ioctl = video_ioctl2,
        .open           = v4l2_fh_open,
        .release        = v4l2_fh_release,
        .poll           = v4l2_ctrl_poll,
};

static const struct v4l2_ioctl_ops tea575x_ioctl_ops = {
        .vidioc_querycap    = vidioc_querycap,
        .vidioc_g_tuner     = vidioc_g_tuner,
        .vidioc_s_tuner     = vidioc_s_tuner,
        .vidioc_g_frequency = vidioc_g_frequency,
        .vidioc_s_frequency = vidioc_s_frequency,
        .vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
        .vidioc_enum_freq_bands = vidioc_enum_freq_bands,
        .vidioc_log_status  = v4l2_ctrl_log_status,
        .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};

static const struct video_device tea575x_radio = {
        .ioctl_ops      = &tea575x_ioctl_ops,
        .release        = video_device_release_empty,
};

static const struct v4l2_ctrl_ops tea575x_ctrl_ops = {
        .s_ctrl = tea575x_s_ctrl,
};


int snd_tea575x_hw_init(struct snd_tea575x *tea)
{
        tea->mute = true;

        /* Not all devices can or know how to read the data back.
           Such devices can set cannot_read_data to true. */
        if (!tea->cannot_read_data) {
                snd_tea575x_write(tea, 0x55AA);
                if (snd_tea575x_read(tea) != 0x55AA)
                        return -ENODEV;
        }

        tea->val = TEA575X_BIT_BAND_FM | TEA575X_BIT_SEARCH_5_28;
        tea->freq = 90500 * 16;         /* 90.5Mhz default */
        snd_tea575x_set_freq(tea);

        return 0;
}
EXPORT_SYMBOL(snd_tea575x_hw_init);

int snd_tea575x_init(struct snd_tea575x *tea, struct module *owner)
{
        int retval = snd_tea575x_hw_init(tea);

        if (retval)
                return retval;

        tea->vd = tea575x_radio;
        video_set_drvdata(&tea->vd, tea);
        mutex_init(&tea->mutex);
        strscpy(tea->vd.name, tea->v4l2_dev->name, sizeof(tea->vd.name));
        tea->vd.lock = &tea->mutex;
        tea->vd.v4l2_dev = tea->v4l2_dev;
        tea->vd.device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
        if (!tea->cannot_read_data)
                tea->vd.device_caps |= V4L2_CAP_HW_FREQ_SEEK;
        tea->fops = tea575x_fops;
        tea->fops.owner = owner;
        tea->vd.fops = &tea->fops;
        /* disable hw_freq_seek if we can't use it */
        if (tea->cannot_read_data)
                v4l2_disable_ioctl(&tea->vd, VIDIOC_S_HW_FREQ_SEEK);

        if (!tea->cannot_mute) {
                tea->vd.ctrl_handler = &tea->ctrl_handler;
                v4l2_ctrl_handler_init(&tea->ctrl_handler, 1);
                v4l2_ctrl_new_std(&tea->ctrl_handler, &tea575x_ctrl_ops,
                                  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
                retval = tea->ctrl_handler.error;
                if (retval) {
                        v4l2_err(tea->v4l2_dev, "can't initialize controls\n");
                        v4l2_ctrl_handler_free(&tea->ctrl_handler);
                        return retval;
                }

                if (tea->ext_init) {
                        retval = tea->ext_init(tea);
                        if (retval) {
                                v4l2_ctrl_handler_free(&tea->ctrl_handler);
                                return retval;
                        }
                }

                v4l2_ctrl_handler_setup(&tea->ctrl_handler);
        }

        retval = video_register_device(&tea->vd, VFL_TYPE_RADIO, tea->radio_nr);
        if (retval) {
                v4l2_err(tea->v4l2_dev, "can't register video device!\n");
                v4l2_ctrl_handler_free(tea->vd.ctrl_handler);
                return retval;
        }

        return 0;
}
EXPORT_SYMBOL(snd_tea575x_init);

void snd_tea575x_exit(struct snd_tea575x *tea)
{
        video_unregister_device(&tea->vd);
        v4l2_ctrl_handler_free(tea->vd.ctrl_handler);
}
EXPORT_SYMBOL(snd_tea575x_exit);