// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * driver/media/radio/radio-tea5764.c
 *
 * Driver for TEA5764 radio chip for linux 2.6.
 * This driver is for TEA5764 chip from NXP, used in EZX phones from Motorola.
 * The I2C protocol is used for communicate with chip.
 *
 * Based in radio-tea5761.c Copyright (C) 2005 Nokia Corporation
 *
 *  Copyright (c) 2008 Fabio Belavenuto <belavenuto@gmail.com>
 *
 * History:
 * 2008-12-06   Fabio Belavenuto <belavenuto@gmail.com>
 *              initial code
 *
 * TODO:
 *  add platform_data support for IRQs platform dependencies
 *  add RDS support
 */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>                 /* Initdata                     */
#include <linux/videodev2.h>            /* kernel radio structs         */
#include <linux/i2c.h>                  /* I2C                          */
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>

#define DRIVER_VERSION  "0.0.2"

#define DRIVER_AUTHOR   "Fabio Belavenuto <belavenuto@gmail.com>"
#define DRIVER_DESC     "A driver for the TEA5764 radio chip for EZX Phones."

#define PINFO(format, ...)\
        printk(KERN_INFO KBUILD_MODNAME ": "\
                DRIVER_VERSION ": " format "\n", ## __VA_ARGS__)
#define PWARN(format, ...)\
        printk(KERN_WARNING KBUILD_MODNAME ": "\
                DRIVER_VERSION ": " format "\n", ## __VA_ARGS__)
# define PDEBUG(format, ...)\
        printk(KERN_DEBUG KBUILD_MODNAME ": "\
                DRIVER_VERSION ": " format "\n", ## __VA_ARGS__)

/* Frequency limits in MHz -- these are European values.  For Japanese
devices, that would be 76000 and 91000.  */
#define FREQ_MIN  87500U
#define FREQ_MAX 108000U
#define FREQ_MUL 16

/* TEA5764 registers */
#define TEA5764_MANID           0x002b
#define TEA5764_CHIPID          0x5764

#define TEA5764_INTREG_BLMSK    0x0001
#define TEA5764_INTREG_FRRMSK   0x0002
#define TEA5764_INTREG_LEVMSK   0x0008
#define TEA5764_INTREG_IFMSK    0x0010
#define TEA5764_INTREG_BLMFLAG  0x0100
#define TEA5764_INTREG_FRRFLAG  0x0200
#define TEA5764_INTREG_LEVFLAG  0x0800
#define TEA5764_INTREG_IFFLAG   0x1000

#define TEA5764_FRQSET_SUD      0x8000
#define TEA5764_FRQSET_SM       0x4000

#define TEA5764_TNCTRL_PUPD1    0x8000
#define TEA5764_TNCTRL_PUPD0    0x4000
#define TEA5764_TNCTRL_BLIM     0x2000
#define TEA5764_TNCTRL_SWPM     0x1000
#define TEA5764_TNCTRL_IFCTC    0x0800
#define TEA5764_TNCTRL_AFM      0x0400
#define TEA5764_TNCTRL_SMUTE    0x0200
#define TEA5764_TNCTRL_SNC      0x0100
#define TEA5764_TNCTRL_MU       0x0080
#define TEA5764_TNCTRL_SSL1     0x0040
#define TEA5764_TNCTRL_SSL0     0x0020
#define TEA5764_TNCTRL_HLSI     0x0010
#define TEA5764_TNCTRL_MST      0x0008
#define TEA5764_TNCTRL_SWP      0x0004
#define TEA5764_TNCTRL_DTC      0x0002
#define TEA5764_TNCTRL_AHLSI    0x0001

#define TEA5764_TUNCHK_LEVEL(x) (((x) & 0x00F0) >> 4)
#define TEA5764_TUNCHK_IFCNT(x) (((x) & 0xFE00) >> 9)
#define TEA5764_TUNCHK_TUNTO    0x0100
#define TEA5764_TUNCHK_LD       0x0008
#define TEA5764_TUNCHK_STEREO   0x0004

#define TEA5764_TESTREG_TRIGFR  0x0800

struct tea5764_regs {
        u16 intreg;                             /* INTFLAG & INTMSK */
        u16 frqset;                             /* FRQSETMSB & FRQSETLSB */
        u16 tnctrl;                             /* TNCTRL1 & TNCTRL2 */
        u16 frqchk;                             /* FRQCHKMSB & FRQCHKLSB */
        u16 tunchk;                             /* IFCHK & LEVCHK */
        u16 testreg;                            /* TESTBITS & TESTMODE */
        u16 rdsstat;                            /* RDSSTAT1 & RDSSTAT2 */
        u16 rdslb;                              /* RDSLBMSB & RDSLBLSB */
        u16 rdspb;                              /* RDSPBMSB & RDSPBLSB */
        u16 rdsbc;                              /* RDSBBC & RDSGBC */
        u16 rdsctrl;                            /* RDSCTRL1 & RDSCTRL2 */
        u16 rdsbbl;                             /* PAUSEDET & RDSBBL */
        u16 manid;                              /* MANID1 & MANID2 */
        u16 chipid;                             /* CHIPID1 & CHIPID2 */
} __attribute__ ((packed));

struct tea5764_write_regs {
        u8 intreg;                              /* INTMSK */
        __be16 frqset;                          /* FRQSETMSB & FRQSETLSB */
        __be16 tnctrl;                          /* TNCTRL1 & TNCTRL2 */
        __be16 testreg;                         /* TESTBITS & TESTMODE */
        __be16 rdsctrl;                         /* RDSCTRL1 & RDSCTRL2 */
        __be16 rdsbbl;                          /* PAUSEDET & RDSBBL */
} __attribute__ ((packed));

#ifdef CONFIG_RADIO_TEA5764_XTAL
#define RADIO_TEA5764_XTAL 1
#else
#define RADIO_TEA5764_XTAL 0
#endif

static int radio_nr = -1;
static int use_xtal = RADIO_TEA5764_XTAL;

struct tea5764_device {
        struct v4l2_device              v4l2_dev;
        struct v4l2_ctrl_handler        ctrl_handler;
        struct i2c_client               *i2c_client;
        struct video_device             vdev;
        struct tea5764_regs             regs;
        struct mutex                    mutex;
};

/* I2C code related */
static int tea5764_i2c_read(struct tea5764_device *radio)
{
        int i;
        u16 *p = (u16 *) &radio->regs;

        struct i2c_msg msgs[1] = {
                {       .addr = radio->i2c_client->addr,
                        .flags = I2C_M_RD,
                        .len = sizeof(radio->regs),
                        .buf = (void *)&radio->regs
                },
        };
        if (i2c_transfer(radio->i2c_client->adapter, msgs, 1) != 1)
                return -EIO;
        for (i = 0; i < sizeof(struct tea5764_regs) / sizeof(u16); i++)
                p[i] = __be16_to_cpu((__force __be16)p[i]);

        return 0;
}

static int tea5764_i2c_write(struct tea5764_device *radio)
{
        struct tea5764_write_regs wr;
        struct tea5764_regs *r = &radio->regs;
        struct i2c_msg msgs[1] = {
                {
                        .addr = radio->i2c_client->addr,
                        .len = sizeof(wr),
                        .buf = (void *)&wr
                },
        };
        wr.intreg  = r->intreg & 0xff;
        wr.frqset  = __cpu_to_be16(r->frqset);
        wr.tnctrl  = __cpu_to_be16(r->tnctrl);
        wr.testreg = __cpu_to_be16(r->testreg);
        wr.rdsctrl = __cpu_to_be16(r->rdsctrl);
        wr.rdsbbl  = __cpu_to_be16(r->rdsbbl);
        if (i2c_transfer(radio->i2c_client->adapter, msgs, 1) != 1)
                return -EIO;
        return 0;
}

static void tea5764_power_up(struct tea5764_device *radio)
{
        struct tea5764_regs *r = &radio->regs;

        if (!(r->tnctrl & TEA5764_TNCTRL_PUPD0)) {
                r->tnctrl &= ~(TEA5764_TNCTRL_AFM | TEA5764_TNCTRL_MU |
                               TEA5764_TNCTRL_HLSI);
                if (!use_xtal)
                        r->testreg |= TEA5764_TESTREG_TRIGFR;
                else
                        r->testreg &= ~TEA5764_TESTREG_TRIGFR;

                r->tnctrl |= TEA5764_TNCTRL_PUPD0;
                tea5764_i2c_write(radio);
        }
}

static void tea5764_power_down(struct tea5764_device *radio)
{
        struct tea5764_regs *r = &radio->regs;

        if (r->tnctrl & TEA5764_TNCTRL_PUPD0) {
                r->tnctrl &= ~TEA5764_TNCTRL_PUPD0;
                tea5764_i2c_write(radio);
        }
}

static void tea5764_set_freq(struct tea5764_device *radio, int freq)
{
        struct tea5764_regs *r = &radio->regs;

        /* formula: (freq [+ or -] 225000) / 8192 */
        if (r->tnctrl & TEA5764_TNCTRL_HLSI)
                r->frqset = (freq + 225000) / 8192;
        else
                r->frqset = (freq - 225000) / 8192;
}

static int tea5764_get_freq(struct tea5764_device *radio)
{
        struct tea5764_regs *r = &radio->regs;

        if (r->tnctrl & TEA5764_TNCTRL_HLSI)
                return (r->frqchk * 8192) - 225000;
        else
                return (r->frqchk * 8192) + 225000;
}

/* tune an frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
static void tea5764_tune(struct tea5764_device *radio, int freq)
{
        tea5764_set_freq(radio, freq);
        if (tea5764_i2c_write(radio))
                PWARN("Could not set frequency!");
}

static void tea5764_set_audout_mode(struct tea5764_device *radio, int audmode)
{
        struct tea5764_regs *r = &radio->regs;
        int tnctrl = r->tnctrl;

        if (audmode == V4L2_TUNER_MODE_MONO)
                r->tnctrl |= TEA5764_TNCTRL_MST;
        else
                r->tnctrl &= ~TEA5764_TNCTRL_MST;
        if (tnctrl != r->tnctrl)
                tea5764_i2c_write(radio);
}

static int tea5764_get_audout_mode(struct tea5764_device *radio)
{
        struct tea5764_regs *r = &radio->regs;

        if (r->tnctrl & TEA5764_TNCTRL_MST)
                return V4L2_TUNER_MODE_MONO;
        else
                return V4L2_TUNER_MODE_STEREO;
}

static void tea5764_mute(struct tea5764_device *radio, int on)
{
        struct tea5764_regs *r = &radio->regs;
        int tnctrl = r->tnctrl;

        if (on)
                r->tnctrl |= TEA5764_TNCTRL_MU;
        else
                r->tnctrl &= ~TEA5764_TNCTRL_MU;
        if (tnctrl != r->tnctrl)
                tea5764_i2c_write(radio);
}

/* V4L2 vidioc */
static int vidioc_querycap(struct file *file, void  *priv,
                                        struct v4l2_capability *v)
{
        struct tea5764_device *radio = video_drvdata(file);
        struct video_device *dev = &radio->vdev;

        strscpy(v->driver, dev->dev.driver->name, sizeof(v->driver));
        strscpy(v->card, dev->name, sizeof(v->card));
        snprintf(v->bus_info, sizeof(v->bus_info),
                 "I2C:%s", dev_name(&dev->dev));
        return 0;
}

static int vidioc_g_tuner(struct file *file, void *priv,
                                struct v4l2_tuner *v)
{
        struct tea5764_device *radio = video_drvdata(file);
        struct tea5764_regs *r = &radio->regs;

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

        strscpy(v->name, "FM", sizeof(v->name));
        v->type = V4L2_TUNER_RADIO;
        tea5764_i2c_read(radio);
        v->rangelow   = FREQ_MIN * FREQ_MUL;
        v->rangehigh  = FREQ_MAX * FREQ_MUL;
        v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
        if (r->tunchk & TEA5764_TUNCHK_STEREO)
                v->rxsubchans = V4L2_TUNER_SUB_STEREO;
        else
                v->rxsubchans = V4L2_TUNER_SUB_MONO;
        v->audmode = tea5764_get_audout_mode(radio);
        v->signal = TEA5764_TUNCHK_LEVEL(r->tunchk) * 0xffff / 0xf;
        v->afc = TEA5764_TUNCHK_IFCNT(r->tunchk);

        return 0;
}

static int vidioc_s_tuner(struct file *file, void *priv,
                                const struct v4l2_tuner *v)
{
        struct tea5764_device *radio = video_drvdata(file);

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

        tea5764_set_audout_mode(radio, v->audmode);
        return 0;
}

static int vidioc_s_frequency(struct file *file, void *priv,
                                const struct v4l2_frequency *f)
{
        struct tea5764_device *radio = video_drvdata(file);
        unsigned freq = f->frequency;

        if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
                return -EINVAL;
        if (freq == 0) {
                /* We special case this as a power down control. */
                tea5764_power_down(radio);
                /* Yes, that's what is returned in this case. This
                   whole special case is non-compliant and should really
                   be replaced with something better, but changing this
                   might well break code that depends on this behavior.
                   So we keep it as-is. */
                return -EINVAL;
        }
        freq = clamp(freq, FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL);
        tea5764_power_up(radio);
        tea5764_tune(radio, (freq * 125) / 2);
        return 0;
}

static int vidioc_g_frequency(struct file *file, void *priv,
                                struct v4l2_frequency *f)
{
        struct tea5764_device *radio = video_drvdata(file);
        struct tea5764_regs *r = &radio->regs;

        if (f->tuner != 0)
                return -EINVAL;
        tea5764_i2c_read(radio);
        f->type = V4L2_TUNER_RADIO;
        if (r->tnctrl & TEA5764_TNCTRL_PUPD0)
                f->frequency = (tea5764_get_freq(radio) * 2) / 125;
        else
                f->frequency = 0;

        return 0;
}

static int tea5764_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct tea5764_device *radio =
                container_of(ctrl->handler, struct tea5764_device, ctrl_handler);

        switch (ctrl->id) {
        case V4L2_CID_AUDIO_MUTE:
                tea5764_mute(radio, ctrl->val);
                return 0;
        }
        return -EINVAL;
}

static const struct v4l2_ctrl_ops tea5764_ctrl_ops = {
        .s_ctrl = tea5764_s_ctrl,
};

/* File system interface */
static const struct v4l2_file_operations tea5764_fops = {
        .owner          = THIS_MODULE,
        .open           = v4l2_fh_open,
        .release        = v4l2_fh_release,
        .poll           = v4l2_ctrl_poll,
        .unlocked_ioctl = video_ioctl2,
};

static const struct v4l2_ioctl_ops tea5764_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_log_status  = v4l2_ctrl_log_status,
        .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};

/* V4L2 interface */
static const struct video_device tea5764_radio_template = {
        .name           = "TEA5764 FM-Radio",
        .fops           = &tea5764_fops,
        .ioctl_ops      = &tea5764_ioctl_ops,
        .release        = video_device_release_empty,
};

/* I2C probe: check if the device exists and register with v4l if it is */
static int tea5764_i2c_probe(struct i2c_client *client)
{
        struct tea5764_device *radio;
        struct v4l2_device *v4l2_dev;
        struct v4l2_ctrl_handler *hdl;
        struct tea5764_regs *r;
        int ret;

        PDEBUG("probe");
        radio = kzalloc_obj(struct tea5764_device);
        if (!radio)
                return -ENOMEM;

        v4l2_dev = &radio->v4l2_dev;
        ret = v4l2_device_register(&client->dev, v4l2_dev);
        if (ret < 0) {
                v4l2_err(v4l2_dev, "could not register v4l2_device\n");
                goto errfr;
        }

        hdl = &radio->ctrl_handler;
        v4l2_ctrl_handler_init(hdl, 1);
        v4l2_ctrl_new_std(hdl, &tea5764_ctrl_ops,
                        V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
        v4l2_dev->ctrl_handler = hdl;
        if (hdl->error) {
                ret = hdl->error;
                v4l2_err(v4l2_dev, "Could not register controls\n");
                goto errunreg;
        }

        mutex_init(&radio->mutex);
        radio->i2c_client = client;
        ret = tea5764_i2c_read(radio);
        if (ret)
                goto errunreg;
        r = &radio->regs;
        PDEBUG("chipid = %04X, manid = %04X", r->chipid, r->manid);
        if (r->chipid != TEA5764_CHIPID ||
                (r->manid & 0x0fff) != TEA5764_MANID) {
                PWARN("This chip is not a TEA5764!");
                ret = -EINVAL;
                goto errunreg;
        }

        radio->vdev = tea5764_radio_template;

        i2c_set_clientdata(client, radio);
        video_set_drvdata(&radio->vdev, radio);
        radio->vdev.lock = &radio->mutex;
        radio->vdev.v4l2_dev = v4l2_dev;
        radio->vdev.device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO;

        /* initialize and power off the chip */
        tea5764_i2c_read(radio);
        tea5764_set_audout_mode(radio, V4L2_TUNER_MODE_STEREO);
        tea5764_mute(radio, 1);
        tea5764_power_down(radio);

        ret = video_register_device(&radio->vdev, VFL_TYPE_RADIO, radio_nr);
        if (ret < 0) {
                PWARN("Could not register video device!");
                goto errunreg;
        }

        PINFO("registered.");
        return 0;
errunreg:
        v4l2_ctrl_handler_free(hdl);
        v4l2_device_unregister(v4l2_dev);
errfr:
        kfree(radio);
        return ret;
}

static void tea5764_i2c_remove(struct i2c_client *client)
{
        struct tea5764_device *radio = i2c_get_clientdata(client);

        PDEBUG("remove");
        if (radio) {
                tea5764_power_down(radio);
                video_unregister_device(&radio->vdev);
                v4l2_ctrl_handler_free(&radio->ctrl_handler);
                v4l2_device_unregister(&radio->v4l2_dev);
                kfree(radio);
        }
}

/* I2C subsystem interface */
static const struct i2c_device_id tea5764_id[] = {
        { "radio-tea5764" },
        { }                                     /* Terminating entry */
};
MODULE_DEVICE_TABLE(i2c, tea5764_id);

static struct i2c_driver tea5764_i2c_driver = {
        .driver = {
                .name = "radio-tea5764",
        },
        .probe = tea5764_i2c_probe,
        .remove = tea5764_i2c_remove,
        .id_table = tea5764_id,
};

module_i2c_driver(tea5764_i2c_driver);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_VERSION(DRIVER_VERSION);

module_param(use_xtal, int, 0);
MODULE_PARM_DESC(use_xtal, "Chip have a xtal connected in board");
module_param(radio_nr, int, 0);
MODULE_PARM_DESC(radio_nr, "video4linux device number to use");