radio-isa.c

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/*
 * Framework for ISA radio drivers.
 * This takes care of all the V4L2 scaffolding, allowing the ISA drivers
 * to concentrate on the actual hardware operation.
 *
 * Copyright (C) 2012 Hans Verkuil <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/videodev2.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>

#include "radio-isa.h"

MODULE_AUTHOR("Hans Verkuil");
MODULE_DESCRIPTION("A framework for ISA radio drivers.");
MODULE_LICENSE("GPL");

#define FREQ_LOW  (87U * 16000U)
#define FREQ_HIGH (108U * 16000U)

static int radio_isa_querycap(struct file *file, void  *priv,
                    struct v4l2_capability *v)
{
    struct radio_isa_card *isa = video_drvdata(file);

    strlcpy(v->driver, isa->drv->driver.driver.name, sizeof(v->driver));
    strlcpy(v->card, isa->drv->card, sizeof(v->card));
    snprintf(v->bus_info, sizeof(v->bus_info), "ISA:%s", isa->v4l2_dev.name);

    v->capabilities = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
    v->device_caps = v->capabilities | V4L2_CAP_DEVICE_CAPS;
    return 0;
}

static int radio_isa_g_tuner(struct file *file, void *priv,
                struct v4l2_tuner *v)
{
    struct radio_isa_card *isa = video_drvdata(file);
    const struct radio_isa_ops *ops = isa->drv->ops;

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

    strlcpy(v->name, "FM", sizeof(v->name));
    v->type = V4L2_TUNER_RADIO;
    v->rangelow = FREQ_LOW;
    v->rangehigh = FREQ_HIGH;
    v->capability = V4L2_TUNER_CAP_LOW;
    if (isa->drv->has_stereo)
        v->capability |= V4L2_TUNER_CAP_STEREO;

    if (ops->g_rxsubchans)
        v->rxsubchans = ops->g_rxsubchans(isa);
    else
        v->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO;
    v->audmode = isa->stereo ? V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
    if (ops->g_signal)
        v->signal = ops->g_signal(isa);
    else
        v->signal = (v->rxsubchans & V4L2_TUNER_SUB_STEREO) ?
                                0xffff : 0;
    return 0;
}

static int radio_isa_s_tuner(struct file *file, void *priv,
                struct v4l2_tuner *v)
{
    struct radio_isa_card *isa = video_drvdata(file);
    const struct radio_isa_ops *ops = isa->drv->ops;

    if (v->index)
        return -EINVAL;
    if (ops->s_stereo) {
        isa->stereo = (v->audmode == V4L2_TUNER_MODE_STEREO);
        return ops->s_stereo(isa, isa->stereo);
    }
    return 0;
}

static int radio_isa_s_frequency(struct file *file, void *priv,
                struct v4l2_frequency *f)
{
    struct radio_isa_card *isa = video_drvdata(file);
    int res;

    if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
        return -EINVAL;
    f->frequency = clamp(f->frequency, FREQ_LOW, FREQ_HIGH);
    res = isa->drv->ops->s_frequency(isa, f->frequency);
    if (res == 0)
        isa->freq = f->frequency;
    return res;
}

static int radio_isa_g_frequency(struct file *file, void *priv,
                struct v4l2_frequency *f)
{
    struct radio_isa_card *isa = video_drvdata(file);

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

static int radio_isa_s_ctrl(struct v4l2_ctrl *ctrl)
{
    struct radio_isa_card *isa =
        container_of(ctrl->handler, struct radio_isa_card, hdl);

    switch (ctrl->id) {
    case V4L2_CID_AUDIO_MUTE:
        return isa->drv->ops->s_mute_volume(isa, ctrl->val,
                isa->volume ? isa->volume->val : 0);
    }
    return -EINVAL;
}

static int radio_isa_log_status(struct file *file, void *priv)
{
    struct radio_isa_card *isa = video_drvdata(file);

    v4l2_info(&isa->v4l2_dev, "I/O Port = 0x%03x\n", isa->io);
    v4l2_ctrl_handler_log_status(&isa->hdl, isa->v4l2_dev.name);
    return 0;
}

static const struct v4l2_ctrl_ops radio_isa_ctrl_ops = {
    .s_ctrl = radio_isa_s_ctrl,
};

static const struct v4l2_file_operations radio_isa_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 radio_isa_ioctl_ops = {
    .vidioc_querycap    = radio_isa_querycap,
    .vidioc_g_tuner     = radio_isa_g_tuner,
    .vidioc_s_tuner     = radio_isa_s_tuner,
    .vidioc_g_frequency = radio_isa_g_frequency,
    .vidioc_s_frequency = radio_isa_s_frequency,
    .vidioc_log_status  = radio_isa_log_status,
    .vidioc_subscribe_event   = v4l2_ctrl_subscribe_event,
    .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};

int radio_isa_match(struct device *pdev, unsigned int dev)
{
    struct radio_isa_driver *drv = pdev->platform_data;

    return drv->probe || drv->io_params[dev] >= 0;
}
EXPORT_SYMBOL_GPL(radio_isa_match);

static bool radio_isa_valid_io(const struct radio_isa_driver *drv, int io)
{
    int i;

    for (i = 0; i < drv->num_of_io_ports; i++)
        if (drv->io_ports[i] == io)
            return true;
    return false;
}

struct radio_isa_card *radio_isa_alloc(struct radio_isa_driver *drv,
                struct device *pdev)
{
    struct v4l2_device *v4l2_dev;
    struct radio_isa_card *isa = drv->ops->alloc();
    if (!isa)
        return NULL;

    dev_set_drvdata(pdev, isa);
    isa->drv = drv;
    v4l2_dev = &isa->v4l2_dev;
    strlcpy(v4l2_dev->name, dev_name(pdev), sizeof(v4l2_dev->name));

    return isa;
}

int radio_isa_common_probe(struct radio_isa_card *isa, struct device *pdev,
                int radio_nr, unsigned region_size)
{
    const struct radio_isa_driver *drv = isa->drv;
    const struct radio_isa_ops *ops = drv->ops;
    struct v4l2_device *v4l2_dev = &isa->v4l2_dev;
    int res;

    if (!request_region(isa->io, region_size, v4l2_dev->name)) {
        v4l2_err(v4l2_dev, "port 0x%x already in use\n", isa->io);
        kfree(isa);
        return -EBUSY;
    }

    res = v4l2_device_register(pdev, v4l2_dev);
    if (res < 0) {
        v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
        goto err_dev_reg;
    }

    v4l2_ctrl_handler_init(&isa->hdl, 1);
    isa->mute = v4l2_ctrl_new_std(&isa->hdl, &radio_isa_ctrl_ops,
                V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
    if (drv->max_volume)
        isa->volume = v4l2_ctrl_new_std(&isa->hdl, &radio_isa_ctrl_ops,
            V4L2_CID_AUDIO_VOLUME, 0, drv->max_volume, 1,
            drv->max_volume);
    v4l2_dev->ctrl_handler = &isa->hdl;
    if (isa->hdl.error) {
        res = isa->hdl.error;
        v4l2_err(v4l2_dev, "Could not register controls\n");
        goto err_hdl;
    }
    if (drv->max_volume)
        v4l2_ctrl_cluster(2, &isa->mute);
    v4l2_dev->ctrl_handler = &isa->hdl;

    mutex_init(&isa->lock);
    isa->vdev.lock = &isa->lock;
    strlcpy(isa->vdev.name, v4l2_dev->name, sizeof(isa->vdev.name));
    isa->vdev.v4l2_dev = v4l2_dev;
    isa->vdev.fops = &radio_isa_fops;
    isa->vdev.ioctl_ops = &radio_isa_ioctl_ops;
    isa->vdev.release = video_device_release_empty;
    set_bit(V4L2_FL_USE_FH_PRIO, &isa->vdev.flags);
    video_set_drvdata(&isa->vdev, isa);
    isa->freq = FREQ_LOW;
    isa->stereo = drv->has_stereo;

    if (ops->init)
        res = ops->init(isa);
    if (!res)
        res = v4l2_ctrl_handler_setup(&isa->hdl);
    if (!res)
        res = ops->s_frequency(isa, isa->freq);
    if (!res && ops->s_stereo)
        res = ops->s_stereo(isa, isa->stereo);
    if (res < 0) {
        v4l2_err(v4l2_dev, "Could not setup card\n");
        goto err_hdl;
    }
    res = video_register_device(&isa->vdev, VFL_TYPE_RADIO, radio_nr);

    if (res < 0) {
        v4l2_err(v4l2_dev, "Could not register device node\n");
        goto err_hdl;
    }

    v4l2_info(v4l2_dev, "Initialized radio card %s on port 0x%03x\n",
            drv->card, isa->io);
    return 0;

err_hdl:
    v4l2_ctrl_handler_free(&isa->hdl);
err_dev_reg:
    release_region(isa->io, region_size);
    kfree(isa);
    return res;
}

int radio_isa_common_remove(struct radio_isa_card *isa, unsigned region_size)
{
    const struct radio_isa_ops *ops = isa->drv->ops;

    ops->s_mute_volume(isa, true, isa->volume ? isa->volume->cur.val : 0);
    video_unregister_device(&isa->vdev);
    v4l2_ctrl_handler_free(&isa->hdl);
    v4l2_device_unregister(&isa->v4l2_dev);
    release_region(isa->io, region_size);
    v4l2_info(&isa->v4l2_dev, "Removed radio card %s\n", isa->drv->card);
    kfree(isa);
    return 0;
}

int radio_isa_probe(struct device *pdev, unsigned int dev)
{
    struct radio_isa_driver *drv = pdev->platform_data;
    const struct radio_isa_ops *ops = drv->ops;
    struct v4l2_device *v4l2_dev;
    struct radio_isa_card *isa;

    isa = radio_isa_alloc(drv, pdev);
    if (!isa)
        return -ENOMEM;
    isa->io = drv->io_params[dev];
    v4l2_dev = &isa->v4l2_dev;

    if (drv->probe && ops->probe) {
        int i;

        for (i = 0; i < drv->num_of_io_ports; ++i) {
            int io = drv->io_ports[i];

            if (request_region(io, drv->region_size, v4l2_dev->name)) {
                bool found = ops->probe(isa, io);

                release_region(io, drv->region_size);
                if (found) {
                    isa->io = io;
                    break;
                }
            }
        }
    }

    if (!radio_isa_valid_io(drv, isa->io)) {
        int i;

        if (isa->io < 0)
            return -ENODEV;
        v4l2_err(v4l2_dev, "you must set an I/O address with io=0x%03x",
                drv->io_ports[0]);
        for (i = 1; i < drv->num_of_io_ports; i++)
            printk(KERN_CONT "/0x%03x", drv->io_ports[i]);
        printk(KERN_CONT ".\n");
        kfree(isa);
        return -EINVAL;
    }

    return radio_isa_common_probe(isa, pdev, drv->radio_nr_params[dev],
                    drv->region_size);
}
EXPORT_SYMBOL_GPL(radio_isa_probe);

int radio_isa_remove(struct device *pdev, unsigned int dev)
{
    struct radio_isa_card *isa = dev_get_drvdata(pdev);

    return radio_isa_common_remove(isa, isa->drv->region_size);
}
EXPORT_SYMBOL_GPL(radio_isa_remove);

#ifdef CONFIG_PNP
int radio_isa_pnp_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
{
    struct pnp_driver *pnp_drv = to_pnp_driver(dev->dev.driver);
    struct radio_isa_driver *drv = container_of(pnp_drv,
                    struct radio_isa_driver, pnp_driver);
    struct radio_isa_card *isa;

    if (!pnp_port_valid(dev, 0))
        return -ENODEV;

    isa = radio_isa_alloc(drv, &dev->dev);
    if (!isa)
        return -ENOMEM;

    isa->io = pnp_port_start(dev, 0);

    return radio_isa_common_probe(isa, &dev->dev, drv->radio_nr_params[0],
                    pnp_port_len(dev, 0));
}
EXPORT_SYMBOL_GPL(radio_isa_pnp_probe);

void radio_isa_pnp_remove(struct pnp_dev *dev)
{
    struct radio_isa_card *isa = dev_get_drvdata(&dev->dev);

    radio_isa_common_remove(isa, pnp_port_len(dev, 0));
}
EXPORT_SYMBOL_GPL(radio_isa_pnp_remove);
#endif