// SPDX-License-Identifier: GPL-2.0-only
/*
 *  FM Driver for Connectivity chip of Texas Instruments.
 *  This file provides interfaces to V4L2 subsystem.
 *
 *  This module registers with V4L2 subsystem as Radio
 *  data system interface (/dev/radio). During the registration,
 *  it will expose two set of function pointers.
 *
 *    1) File operation related API (open, close, read, write, poll...etc).
 *    2) Set of V4L2 IOCTL complaint API.
 *
 *  Copyright (C) 2011 Texas Instruments
 *  Author: Raja Mani <raja_mani@ti.com>
 *  Author: Manjunatha Halli <manjunatha_halli@ti.com>
 */

#include <linux/export.h>

#include "fmdrv.h"
#include "fmdrv_v4l2.h"
#include "fmdrv_common.h"
#include "fmdrv_rx.h"
#include "fmdrv_tx.h"

static struct video_device gradio_dev;
static u8 radio_disconnected;

/* -- V4L2 RADIO (/dev/radioX) device file operation interfaces --- */

/* Read RX RDS data */
static ssize_t fm_v4l2_fops_read(struct file *file, char __user * buf,
                                        size_t count, loff_t *ppos)
{
        u8 rds_mode;
        int ret;
        struct fmdev *fmdev;

        fmdev = video_drvdata(file);

        if (!radio_disconnected) {
                fmerr("FM device is already disconnected\n");
                return -EIO;
        }

        if (mutex_lock_interruptible(&fmdev->mutex))
                return -ERESTARTSYS;

        /* Turn on RDS mode if it is disabled */
        ret = fm_rx_get_rds_mode(fmdev, &rds_mode);
        if (ret < 0) {
                fmerr("Unable to read current rds mode\n");
                goto read_unlock;
        }

        if (rds_mode == FM_RDS_DISABLE) {
                ret = fmc_set_rds_mode(fmdev, FM_RDS_ENABLE);
                if (ret < 0) {
                        fmerr("Failed to enable rds mode\n");
                        goto read_unlock;
                }
        }

        /* Copy RDS data from internal buffer to user buffer */
        ret = fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);
read_unlock:
        mutex_unlock(&fmdev->mutex);
        return ret;
}

/* Write TX RDS data */
static ssize_t fm_v4l2_fops_write(struct file *file, const char __user * buf,
                size_t count, loff_t *ppos)
{
        struct tx_rds rds;
        int ret;
        struct fmdev *fmdev;

        ret = copy_from_user(&rds, buf, sizeof(rds));
        rds.text[sizeof(rds.text) - 1] = '\0';
        fmdbg("(%d)type: %d, text %s, af %d\n",
                   ret, rds.text_type, rds.text, rds.af_freq);
        if (ret)
                return -EFAULT;

        fmdev = video_drvdata(file);
        if (mutex_lock_interruptible(&fmdev->mutex))
                return -ERESTARTSYS;
        fm_tx_set_radio_text(fmdev, rds.text, rds.text_type);
        fm_tx_set_af(fmdev, rds.af_freq);
        mutex_unlock(&fmdev->mutex);

        return sizeof(rds);
}

static __poll_t fm_v4l2_fops_poll(struct file *file, struct poll_table_struct *pts)
{
        int ret;
        struct fmdev *fmdev;

        fmdev = video_drvdata(file);
        mutex_lock(&fmdev->mutex);
        ret = fmc_is_rds_data_available(fmdev, file, pts);
        mutex_unlock(&fmdev->mutex);
        if (ret < 0)
                return EPOLLIN | EPOLLRDNORM;

        return 0;
}

/*
 * Handle open request for "/dev/radioX" device.
 * Start with FM RX mode as default.
 */
static int fm_v4l2_fops_open(struct file *file)
{
        int ret;
        struct fmdev *fmdev = NULL;

        /* Don't allow multiple open */
        if (radio_disconnected) {
                fmerr("FM device is already opened\n");
                return -EBUSY;
        }

        fmdev = video_drvdata(file);

        if (mutex_lock_interruptible(&fmdev->mutex))
                return -ERESTARTSYS;
        ret = fmc_prepare(fmdev);
        if (ret < 0) {
                fmerr("Unable to prepare FM CORE\n");
                goto open_unlock;
        }

        fmdbg("Load FM RX firmware..\n");

        ret = fmc_set_mode(fmdev, FM_MODE_RX);
        if (ret < 0) {
                fmerr("Unable to load FM RX firmware\n");
                goto open_unlock;
        }
        radio_disconnected = 1;

open_unlock:
        mutex_unlock(&fmdev->mutex);
        return ret;
}

static int fm_v4l2_fops_release(struct file *file)
{
        int ret;
        struct fmdev *fmdev;

        fmdev = video_drvdata(file);
        if (!radio_disconnected) {
                fmdbg("FM device is already closed\n");
                return 0;
        }

        mutex_lock(&fmdev->mutex);
        ret = fmc_set_mode(fmdev, FM_MODE_OFF);
        if (ret < 0) {
                fmerr("Unable to turn off the chip\n");
                goto release_unlock;
        }

        ret = fmc_release(fmdev);
        if (ret < 0) {
                fmerr("FM CORE release failed\n");
                goto release_unlock;
        }
        radio_disconnected = 0;

release_unlock:
        mutex_unlock(&fmdev->mutex);
        return ret;
}

/* V4L2 RADIO (/dev/radioX) device IOCTL interfaces */
static int fm_v4l2_vidioc_querycap(struct file *file, void *priv,
                struct v4l2_capability *capability)
{
        strscpy(capability->driver, FM_DRV_NAME, sizeof(capability->driver));
        strscpy(capability->card, FM_DRV_CARD_SHORT_NAME,
                sizeof(capability->card));
        sprintf(capability->bus_info, "UART");
        return 0;
}

static int fm_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
{
        struct fmdev *fmdev = container_of(ctrl->handler,
                        struct fmdev, ctrl_handler);

        switch (ctrl->id) {
        case  V4L2_CID_TUNE_ANTENNA_CAPACITOR:
                ctrl->val = fm_tx_get_tune_cap_val(fmdev);
                break;
        default:
                fmwarn("%s: Unknown IOCTL: %d\n", __func__, ctrl->id);
                break;
        }

        return 0;
}

static int fm_v4l2_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct fmdev *fmdev = container_of(ctrl->handler,
                        struct fmdev, ctrl_handler);

        switch (ctrl->id) {
        case V4L2_CID_AUDIO_VOLUME:     /* set volume */
                return fm_rx_set_volume(fmdev, (u16)ctrl->val);

        case V4L2_CID_AUDIO_MUTE:       /* set mute */
                return fmc_set_mute_mode(fmdev, (u8)ctrl->val);

        case V4L2_CID_TUNE_POWER_LEVEL:
                /* set TX power level - ext control */
                return fm_tx_set_pwr_lvl(fmdev, (u8)ctrl->val);

        case V4L2_CID_TUNE_PREEMPHASIS:
                return fm_tx_set_preemph_filter(fmdev, (u8) ctrl->val);

        default:
                return -EINVAL;
        }
}

static int fm_v4l2_vidioc_g_audio(struct file *file, void *priv,
                struct v4l2_audio *audio)
{
        memset(audio, 0, sizeof(*audio));
        strscpy(audio->name, "Radio", sizeof(audio->name));
        audio->capability = V4L2_AUDCAP_STEREO;

        return 0;
}

static int fm_v4l2_vidioc_s_audio(struct file *file, void *priv,
                const struct v4l2_audio *audio)
{
        if (audio->index != 0)
                return -EINVAL;

        return 0;
}

/* Get tuner attributes. If current mode is NOT RX, return error */
static int fm_v4l2_vidioc_g_tuner(struct file *file, void *priv,
                struct v4l2_tuner *tuner)
{
        struct fmdev *fmdev = video_drvdata(file);
        u32 bottom_freq;
        u32 top_freq;
        u16 stereo_mono_mode;
        u16 rssilvl;
        int ret;

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

        if (fmdev->curr_fmmode != FM_MODE_RX)
                return -EPERM;

        ret = fm_rx_get_band_freq_range(fmdev, &bottom_freq, &top_freq);
        if (ret != 0)
                return ret;

        ret = fm_rx_get_stereo_mono(fmdev, &stereo_mono_mode);
        if (ret != 0)
                return ret;

        ret = fm_rx_get_rssi_level(fmdev, &rssilvl);
        if (ret != 0)
                return ret;

        strscpy(tuner->name, "FM", sizeof(tuner->name));
        tuner->type = V4L2_TUNER_RADIO;
        /* Store rangelow and rangehigh freq in unit of 62.5 Hz */
        tuner->rangelow = bottom_freq * 16;
        tuner->rangehigh = top_freq * 16;
        tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO |
        ((fmdev->rx.rds.flag == FM_RDS_ENABLE) ? V4L2_TUNER_SUB_RDS : 0);
        tuner->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
                            V4L2_TUNER_CAP_LOW |
                            V4L2_TUNER_CAP_HWSEEK_BOUNDED |
                            V4L2_TUNER_CAP_HWSEEK_WRAP;
        tuner->audmode = (stereo_mono_mode ?
                          V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO);

        /*
         * Actual rssi value lies in between -128 to +127.
         * Convert this range from 0 to 255 by adding +128
         */
        rssilvl += 128;

        /*
         * Return signal strength value should be within 0 to 65535.
         * Find out correct signal radio by multiplying (65535/255) = 257
         */
        tuner->signal = rssilvl * 257;
        tuner->afc = 0;

        return ret;
}

/*
 * Set tuner attributes. If current mode is NOT RX, set to RX.
 * Currently, we set only audio mode (mono/stereo) and RDS state (on/off).
 * Should we set other tuner attributes, too?
 */
static int fm_v4l2_vidioc_s_tuner(struct file *file, void *priv,
                const struct v4l2_tuner *tuner)
{
        struct fmdev *fmdev = video_drvdata(file);
        u16 aud_mode;
        u8 rds_mode;
        int ret;

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

        aud_mode = (tuner->audmode == V4L2_TUNER_MODE_STEREO) ?
                        FM_STEREO_MODE : FM_MONO_MODE;
        rds_mode = (tuner->rxsubchans & V4L2_TUNER_SUB_RDS) ?
                        FM_RDS_ENABLE : FM_RDS_DISABLE;

        if (fmdev->curr_fmmode != FM_MODE_RX) {
                ret = fmc_set_mode(fmdev, FM_MODE_RX);
                if (ret < 0) {
                        fmerr("Failed to set RX mode\n");
                        return ret;
                }
        }

        ret = fmc_set_stereo_mono(fmdev, aud_mode);
        if (ret < 0) {
                fmerr("Failed to set RX stereo/mono mode\n");
                return ret;
        }

        ret = fmc_set_rds_mode(fmdev, rds_mode);
        if (ret < 0)
                fmerr("Failed to set RX RDS mode\n");

        return ret;
}

/* Get tuner or modulator radio frequency */
static int fm_v4l2_vidioc_g_freq(struct file *file, void *priv,
                struct v4l2_frequency *freq)
{
        struct fmdev *fmdev = video_drvdata(file);
        int ret;

        ret = fmc_get_freq(fmdev, &freq->frequency);
        if (ret < 0) {
                fmerr("Failed to get frequency\n");
                return ret;
        }

        /* Frequency unit of 62.5 Hz*/
        freq->frequency = (u32) freq->frequency * 16;

        return 0;
}

/* Set tuner or modulator radio frequency */
static int fm_v4l2_vidioc_s_freq(struct file *file, void *priv,
                const struct v4l2_frequency *freq)
{
        struct fmdev *fmdev = video_drvdata(file);

        /*
         * As V4L2_TUNER_CAP_LOW is set 1 user sends the frequency
         * in units of 62.5 Hz.
         */
        return fmc_set_freq(fmdev, freq->frequency / 16);
}

/* Set hardware frequency seek. If current mode is NOT RX, set it RX. */
static int fm_v4l2_vidioc_s_hw_freq_seek(struct file *file, void *priv,
                const struct v4l2_hw_freq_seek *seek)
{
        struct fmdev *fmdev = video_drvdata(file);
        int ret;

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

        if (fmdev->curr_fmmode != FM_MODE_RX) {
                ret = fmc_set_mode(fmdev, FM_MODE_RX);
                if (ret != 0) {
                        fmerr("Failed to set RX mode\n");
                        return ret;
                }
        }

        ret = fm_rx_seek(fmdev, seek->seek_upward, seek->wrap_around,
                        seek->spacing);
        if (ret < 0)
                fmerr("RX seek failed - %d\n", ret);

        return ret;
}
/* Get modulator attributes. If mode is not TX, return no attributes. */
static int fm_v4l2_vidioc_g_modulator(struct file *file, void *priv,
                struct v4l2_modulator *mod)
{
        struct fmdev *fmdev = video_drvdata(file);

        if (mod->index != 0)
                return -EINVAL;

        if (fmdev->curr_fmmode != FM_MODE_TX)
                return -EPERM;

        mod->txsubchans = ((fmdev->tx_data.aud_mode == FM_STEREO_MODE) ?
                                V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO) |
                                ((fmdev->tx_data.rds.flag == FM_RDS_ENABLE) ?
                                V4L2_TUNER_SUB_RDS : 0);

        mod->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
                                V4L2_TUNER_CAP_LOW;

        return 0;
}

/* Set modulator attributes. If mode is not TX, set to TX. */
static int fm_v4l2_vidioc_s_modulator(struct file *file, void *priv,
                const struct v4l2_modulator *mod)
{
        struct fmdev *fmdev = video_drvdata(file);
        u8 rds_mode;
        u16 aud_mode;
        int ret;

        if (mod->index != 0)
                return -EINVAL;

        if (fmdev->curr_fmmode != FM_MODE_TX) {
                ret = fmc_set_mode(fmdev, FM_MODE_TX);
                if (ret != 0) {
                        fmerr("Failed to set TX mode\n");
                        return ret;
                }
        }

        aud_mode = (mod->txsubchans & V4L2_TUNER_SUB_STEREO) ?
                        FM_STEREO_MODE : FM_MONO_MODE;
        rds_mode = (mod->txsubchans & V4L2_TUNER_SUB_RDS) ?
                        FM_RDS_ENABLE : FM_RDS_DISABLE;
        ret = fm_tx_set_stereo_mono(fmdev, aud_mode);
        if (ret < 0) {
                fmerr("Failed to set mono/stereo mode for TX\n");
                return ret;
        }
        ret = fm_tx_set_rds_mode(fmdev, rds_mode);
        if (ret < 0)
                fmerr("Failed to set rds mode for TX\n");

        return ret;
}

static const struct v4l2_file_operations fm_drv_fops = {
        .owner = THIS_MODULE,
        .read = fm_v4l2_fops_read,
        .write = fm_v4l2_fops_write,
        .poll = fm_v4l2_fops_poll,
        .unlocked_ioctl = video_ioctl2,
        .open = fm_v4l2_fops_open,
        .release = fm_v4l2_fops_release,
};

static const struct v4l2_ctrl_ops fm_ctrl_ops = {
        .s_ctrl = fm_v4l2_s_ctrl,
        .g_volatile_ctrl = fm_g_volatile_ctrl,
};
static const struct v4l2_ioctl_ops fm_drv_ioctl_ops = {
        .vidioc_querycap = fm_v4l2_vidioc_querycap,
        .vidioc_g_audio = fm_v4l2_vidioc_g_audio,
        .vidioc_s_audio = fm_v4l2_vidioc_s_audio,
        .vidioc_g_tuner = fm_v4l2_vidioc_g_tuner,
        .vidioc_s_tuner = fm_v4l2_vidioc_s_tuner,
        .vidioc_g_frequency = fm_v4l2_vidioc_g_freq,
        .vidioc_s_frequency = fm_v4l2_vidioc_s_freq,
        .vidioc_s_hw_freq_seek = fm_v4l2_vidioc_s_hw_freq_seek,
        .vidioc_g_modulator = fm_v4l2_vidioc_g_modulator,
        .vidioc_s_modulator = fm_v4l2_vidioc_s_modulator
};

/* V4L2 RADIO device parent structure */
static const struct video_device fm_viddev_template = {
        .fops = &fm_drv_fops,
        .ioctl_ops = &fm_drv_ioctl_ops,
        .name = FM_DRV_NAME,
        .release = video_device_release_empty,
        /*
         * To ensure both the tuner and modulator ioctls are accessible we
         * set the vfl_dir to M2M to indicate this.
         *
         * It is not really a mem2mem device of course, but it can both receive
         * and transmit using the same radio device. It's the only radio driver
         * that does this and it should really be split in two radio devices,
         * but that would affect applications using this driver.
         */
        .vfl_dir = VFL_DIR_M2M,
        .device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_TUNER | V4L2_CAP_RADIO |
                       V4L2_CAP_MODULATOR | V4L2_CAP_AUDIO |
                       V4L2_CAP_READWRITE | V4L2_CAP_RDS_CAPTURE,
};

int fm_v4l2_init_video_device(struct fmdev *fmdev, int radio_nr)
{
        struct v4l2_ctrl *ctrl;
        int ret;

        strscpy(fmdev->v4l2_dev.name, FM_DRV_NAME,
                sizeof(fmdev->v4l2_dev.name));
        ret = v4l2_device_register(NULL, &fmdev->v4l2_dev);
        if (ret < 0)
                return ret;

        /* Init mutex for core locking */
        mutex_init(&fmdev->mutex);

        /* Setup FM driver's V4L2 properties */
        gradio_dev = fm_viddev_template;

        video_set_drvdata(&gradio_dev, fmdev);

        gradio_dev.lock = &fmdev->mutex;
        gradio_dev.v4l2_dev = &fmdev->v4l2_dev;

        /* Register with V4L2 subsystem as RADIO device */
        if (video_register_device(&gradio_dev, VFL_TYPE_RADIO, radio_nr)) {
                v4l2_device_unregister(&fmdev->v4l2_dev);
                fmerr("Could not register video device\n");
                return -ENOMEM;
        }

        fmdev->radio_dev = &gradio_dev;

        /* Register to v4l2 ctrl handler framework */
        fmdev->radio_dev->ctrl_handler = &fmdev->ctrl_handler;

        ret = v4l2_ctrl_handler_init(&fmdev->ctrl_handler, 5);
        if (ret < 0) {
                fmerr("(fmdev): Can't init ctrl handler\n");
                v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
                video_unregister_device(fmdev->radio_dev);
                v4l2_device_unregister(&fmdev->v4l2_dev);
                return -EBUSY;
        }

        /*
         * Following controls are handled by V4L2 control framework.
         * Added in ascending ID order.
         */
        v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
                        V4L2_CID_AUDIO_VOLUME, FM_RX_VOLUME_MIN,
                        FM_RX_VOLUME_MAX, 1, FM_RX_VOLUME_MAX);

        v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
                        V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);

        v4l2_ctrl_new_std_menu(&fmdev->ctrl_handler, &fm_ctrl_ops,
                        V4L2_CID_TUNE_PREEMPHASIS, V4L2_PREEMPHASIS_75_uS,
                        0, V4L2_PREEMPHASIS_75_uS);

        v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
                        V4L2_CID_TUNE_POWER_LEVEL, FM_PWR_LVL_LOW,
                        FM_PWR_LVL_HIGH, 1, FM_PWR_LVL_HIGH);

        ctrl = v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
                        V4L2_CID_TUNE_ANTENNA_CAPACITOR, 0,
                        255, 1, 255);

        if (ctrl)
                ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;

        return 0;
}

void *fm_v4l2_deinit_video_device(void)
{
        struct fmdev *fmdev;


        fmdev = video_get_drvdata(&gradio_dev);

        /* Unregister to v4l2 ctrl handler framework*/
        v4l2_ctrl_handler_free(&fmdev->ctrl_handler);

        /* Unregister RADIO device from V4L2 subsystem */
        video_unregister_device(&gradio_dev);

        v4l2_device_unregister(&fmdev->v4l2_dev);

        return fmdev;
}