// SPDX-License-Identifier: GPL-2.0-only
/* SF16-FMI, SF16-FMP and SF16-FMD radio driver for Linux radio support
 * heavily based on rtrack driver...
 * (c) 1997 M. Kirkwood
 * (c) 1998 Petr Vandrovec, vandrove@vc.cvut.cz
 *
 * Fitted to new interface by Alan Cox <alan@lxorguk.ukuu.org.uk>
 * Made working and cleaned up functions <mikael.hedin@irf.se>
 * Support for ISAPnP by Ladislav Michl <ladis@psi.cz>
 *
 * Notes on the hardware
 *
 *  Frequency control is done digitally -- ie out(port,encodefreq(95.8));
 *  No volume control - only mute/unmute - you have to use line volume
 *  control on SB-part of SF16-FMI/SF16-FMP/SF16-FMD
 *
 * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@kernel.org>
 */

#include <linux/kernel.h>       /* __setup                      */
#include <linux/module.h>       /* Modules                      */
#include <linux/init.h>         /* Initdata                     */
#include <linux/ioport.h>       /* request_region               */
#include <linux/delay.h>        /* udelay                       */
#include <linux/isapnp.h>
#include <linux/mutex.h>
#include <linux/videodev2.h>    /* kernel radio structs         */
#include <linux/io.h>           /* outb, outb_p                 */
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>
#include "lm7000.h"

MODULE_AUTHOR("Petr Vandrovec, vandrove@vc.cvut.cz and M. Kirkwood");
MODULE_DESCRIPTION("A driver for the SF16-FMI, SF16-FMP and SF16-FMD radio.");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.0.3");

static int io = -1;
static int radio_nr = -1;

module_param(io, int, 0);
MODULE_PARM_DESC(io, "I/O address of the SF16-FMI/SF16-FMP/SF16-FMD card (0x284 or 0x384)");
module_param(radio_nr, int, 0);

struct fmi
{
        struct v4l2_device v4l2_dev;
        struct v4l2_ctrl_handler hdl;
        struct video_device vdev;
        int io;
        bool mute;
        u32 curfreq; /* freq in kHz */
        struct mutex lock;
};

static struct fmi fmi_card;
static struct pnp_dev *dev;
static bool pnp_attached;

#define RSF16_MINFREQ (87U * 16000)
#define RSF16_MAXFREQ (108U * 16000)

#define FMI_BIT_TUN_CE          (1 << 0)
#define FMI_BIT_TUN_CLK         (1 << 1)
#define FMI_BIT_TUN_DATA        (1 << 2)
#define FMI_BIT_VOL_SW          (1 << 3)
#define FMI_BIT_TUN_STRQ        (1 << 4)

static void fmi_set_pins(void *handle, u8 pins)
{
        struct fmi *fmi = handle;
        u8 bits = FMI_BIT_TUN_STRQ;

        if (!fmi->mute)
                bits |= FMI_BIT_VOL_SW;

        if (pins & LM7000_DATA)
                bits |= FMI_BIT_TUN_DATA;
        if (pins & LM7000_CLK)
                bits |= FMI_BIT_TUN_CLK;
        if (pins & LM7000_CE)
                bits |= FMI_BIT_TUN_CE;

        mutex_lock(&fmi->lock);
        outb_p(bits, fmi->io);
        mutex_unlock(&fmi->lock);
}

static inline void fmi_mute(struct fmi *fmi)
{
        mutex_lock(&fmi->lock);
        outb(0x00, fmi->io);
        mutex_unlock(&fmi->lock);
}

static inline void fmi_unmute(struct fmi *fmi)
{
        mutex_lock(&fmi->lock);
        outb(0x08, fmi->io);
        mutex_unlock(&fmi->lock);
}

static inline int fmi_getsigstr(struct fmi *fmi)
{
        int val;
        int res;

        mutex_lock(&fmi->lock);
        val = fmi->mute ? 0x00 : 0x08;  /* mute/unmute */
        outb(val, fmi->io);
        outb(val | 0x10, fmi->io);
        msleep(143);            /* was schedule_timeout(HZ/7) */
        res = (int)inb(fmi->io + 1);
        outb(val, fmi->io);

        mutex_unlock(&fmi->lock);
        return (res & 2) ? 0 : 0xFFFF;
}

static void fmi_set_freq(struct fmi *fmi)
{
        fmi->curfreq = clamp(fmi->curfreq, RSF16_MINFREQ, RSF16_MAXFREQ);
        /* rounding in steps of 800 to match the freq
           that will be used */
        lm7000_set_freq((fmi->curfreq / 800) * 800, fmi, fmi_set_pins);
}

static int vidioc_querycap(struct file *file, void  *priv,
                                        struct v4l2_capability *v)
{
        strscpy(v->driver, "radio-sf16fmi", sizeof(v->driver));
        strscpy(v->card, "SF16-FMI/FMP/FMD radio", sizeof(v->card));
        strscpy(v->bus_info, "ISA:radio-sf16fmi", sizeof(v->bus_info));
        return 0;
}

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

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

        strscpy(v->name, "FM", sizeof(v->name));
        v->type = V4L2_TUNER_RADIO;
        v->rangelow = RSF16_MINFREQ;
        v->rangehigh = RSF16_MAXFREQ;
        v->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;
        v->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_LOW;
        v->audmode = V4L2_TUNER_MODE_STEREO;
        v->signal = fmi_getsigstr(fmi);
        return 0;
}

static int vidioc_s_tuner(struct file *file, void *priv,
                                        const struct v4l2_tuner *v)
{
        return v->index ? -EINVAL : 0;
}

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

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

        fmi->curfreq = f->frequency;
        fmi_set_freq(fmi);

        return 0;
}

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

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

static int fmi_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct fmi *fmi = container_of(ctrl->handler, struct fmi, hdl);

        switch (ctrl->id) {
        case V4L2_CID_AUDIO_MUTE:
                if (ctrl->val)
                        fmi_mute(fmi);
                else
                        fmi_unmute(fmi);
                fmi->mute = ctrl->val;
                return 0;
        }
        return -EINVAL;
}

static const struct v4l2_ctrl_ops fmi_ctrl_ops = {
        .s_ctrl = fmi_s_ctrl,
};

static const struct v4l2_file_operations fmi_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 fmi_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,
};

/* ladis: this is my card. does any other types exist? */
static struct isapnp_device_id id_table[] = {
                /* SF16-FMI */
        {       ISAPNP_ANY_ID, ISAPNP_ANY_ID,
                ISAPNP_VENDOR('M','F','R'), ISAPNP_FUNCTION(0xad10), 0},
                /* SF16-FMD */
        {       ISAPNP_ANY_ID, ISAPNP_ANY_ID,
                ISAPNP_VENDOR('M','F','R'), ISAPNP_FUNCTION(0xad12), 0},
        {       ISAPNP_CARD_END, },
};

MODULE_DEVICE_TABLE(isapnp, id_table);

static int __init isapnp_fmi_probe(void)
{
        int i = 0;

        while (id_table[i].card_vendor != 0 && dev == NULL) {
                dev = pnp_find_dev(NULL, id_table[i].vendor,
                                   id_table[i].function, NULL);
                i++;
        }

        if (!dev)
                return -ENODEV;
        if (pnp_device_attach(dev) < 0)
                return -EAGAIN;
        if (pnp_activate_dev(dev) < 0) {
                printk(KERN_ERR "radio-sf16fmi: PnP configure failed (out of resources?)\n");
                pnp_device_detach(dev);
                return -ENOMEM;
        }
        if (!pnp_port_valid(dev, 0)) {
                pnp_device_detach(dev);
                return -ENODEV;
        }

        i = pnp_port_start(dev, 0);
        printk(KERN_INFO "radio-sf16fmi: PnP reports card at %#x\n", i);

        return i;
}

static int __init fmi_init(void)
{
        struct fmi *fmi = &fmi_card;
        struct v4l2_device *v4l2_dev = &fmi->v4l2_dev;
        struct v4l2_ctrl_handler *hdl = &fmi->hdl;
        int res, i;
        static const int probe_ports[] = { 0, 0x284, 0x384 };

        if (io < 0) {
                for (i = 0; i < ARRAY_SIZE(probe_ports); i++) {
                        io = probe_ports[i];
                        if (io == 0) {
                                io = isapnp_fmi_probe();
                                if (io < 0)
                                        continue;
                                pnp_attached = true;
                        }
                        if (!request_region(io, 2, "radio-sf16fmi")) {
                                if (pnp_attached)
                                        pnp_device_detach(dev);
                                io = -1;
                                continue;
                        }
                        if (pnp_attached ||
                            ((inb(io) & 0xf9) == 0xf9 && (inb(io) & 0x4) == 0))
                                break;
                        release_region(io, 2);
                        io = -1;
                }
        } else {
                if (!request_region(io, 2, "radio-sf16fmi")) {
                        printk(KERN_ERR "radio-sf16fmi: port %#x already in use\n", io);
                        return -EBUSY;
                }
                if (inb(io) == 0xff) {
                        printk(KERN_ERR "radio-sf16fmi: card not present at %#x\n", io);
                        release_region(io, 2);
                        return -ENODEV;
                }
        }
        if (io < 0) {
                printk(KERN_ERR "radio-sf16fmi: no cards found\n");
                return -ENODEV;
        }

        strscpy(v4l2_dev->name, "sf16fmi", sizeof(v4l2_dev->name));
        fmi->io = io;

        res = v4l2_device_register(NULL, v4l2_dev);
        if (res < 0) {
                release_region(fmi->io, 2);
                if (pnp_attached)
                        pnp_device_detach(dev);
                v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
                return res;
        }

        v4l2_ctrl_handler_init(hdl, 1);
        v4l2_ctrl_new_std(hdl, &fmi_ctrl_ops,
                        V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
        v4l2_dev->ctrl_handler = hdl;
        if (hdl->error) {
                res = hdl->error;
                v4l2_err(v4l2_dev, "Could not register controls\n");
                v4l2_ctrl_handler_free(hdl);
                v4l2_device_unregister(v4l2_dev);
                return res;
        }

        strscpy(fmi->vdev.name, v4l2_dev->name, sizeof(fmi->vdev.name));
        fmi->vdev.v4l2_dev = v4l2_dev;
        fmi->vdev.fops = &fmi_fops;
        fmi->vdev.ioctl_ops = &fmi_ioctl_ops;
        fmi->vdev.release = video_device_release_empty;
        fmi->vdev.device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
        video_set_drvdata(&fmi->vdev, fmi);

        mutex_init(&fmi->lock);

        /* mute card and set default frequency */
        fmi->mute = true;
        fmi->curfreq = RSF16_MINFREQ;
        fmi_set_freq(fmi);

        if (video_register_device(&fmi->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
                v4l2_ctrl_handler_free(hdl);
                v4l2_device_unregister(v4l2_dev);
                release_region(fmi->io, 2);
                if (pnp_attached)
                        pnp_device_detach(dev);
                return -EINVAL;
        }

        v4l2_info(v4l2_dev, "card driver at 0x%x\n", fmi->io);
        return 0;
}

static void __exit fmi_exit(void)
{
        struct fmi *fmi = &fmi_card;

        v4l2_ctrl_handler_free(&fmi->hdl);
        video_unregister_device(&fmi->vdev);
        v4l2_device_unregister(&fmi->v4l2_dev);
        release_region(fmi->io, 2);
        if (dev && pnp_attached)
                pnp_device_detach(dev);
}

module_init(fmi_init);
module_exit(fmi_exit);