linux/drivers/media/radio/si4713/radio-platform-si4713.c
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   1/*
   2 * drivers/media/radio/radio-si4713.c
   3 *
   4 * Platform Driver for Silicon Labs Si4713 FM Radio Transmitter:
   5 *
   6 * Copyright (c) 2008 Instituto Nokia de Tecnologia - INdT
   7 * Contact: Eduardo Valentin <eduardo.valentin@nokia.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License as published by
  11 * the Free Software Foundation; either version 2 of the License, or
  12 * (at your option) any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 */
  19
  20#include <linux/kernel.h>
  21#include <linux/module.h>
  22#include <linux/init.h>
  23#include <linux/platform_device.h>
  24#include <linux/i2c.h>
  25#include <linux/videodev2.h>
  26#include <linux/slab.h>
  27#include <media/v4l2-device.h>
  28#include <media/v4l2-common.h>
  29#include <media/v4l2-ioctl.h>
  30#include <media/v4l2-fh.h>
  31#include <media/v4l2-ctrls.h>
  32#include <media/v4l2-event.h>
  33#include "si4713.h"
  34
  35/* module parameters */
  36static int radio_nr = -1;       /* radio device minor (-1 ==> auto assign) */
  37module_param(radio_nr, int, 0);
  38MODULE_PARM_DESC(radio_nr,
  39                 "Minor number for radio device (-1 ==> auto assign)");
  40
  41MODULE_LICENSE("GPL v2");
  42MODULE_AUTHOR("Eduardo Valentin <eduardo.valentin@nokia.com>");
  43MODULE_DESCRIPTION("Platform driver for Si4713 FM Radio Transmitter");
  44MODULE_VERSION("0.0.1");
  45MODULE_ALIAS("platform:radio-si4713");
  46
  47/* Driver state struct */
  48struct radio_si4713_device {
  49        struct v4l2_device              v4l2_dev;
  50        struct video_device             radio_dev;
  51        struct mutex lock;
  52};
  53
  54/* radio_si4713_fops - file operations interface */
  55static const struct v4l2_file_operations radio_si4713_fops = {
  56        .owner          = THIS_MODULE,
  57        .open = v4l2_fh_open,
  58        .release = v4l2_fh_release,
  59        .poll = v4l2_ctrl_poll,
  60        /* Note: locking is done at the subdev level in the i2c driver. */
  61        .unlocked_ioctl = video_ioctl2,
  62};
  63
  64/* Video4Linux Interface */
  65
  66/* radio_si4713_querycap - query device capabilities */
  67static int radio_si4713_querycap(struct file *file, void *priv,
  68                                        struct v4l2_capability *capability)
  69{
  70        strscpy(capability->driver, "radio-si4713", sizeof(capability->driver));
  71        strscpy(capability->card, "Silicon Labs Si4713 Modulator",
  72                sizeof(capability->card));
  73        strscpy(capability->bus_info, "platform:radio-si4713",
  74                sizeof(capability->bus_info));
  75        capability->device_caps = V4L2_CAP_MODULATOR | V4L2_CAP_RDS_OUTPUT;
  76        capability->capabilities = capability->device_caps | V4L2_CAP_DEVICE_CAPS;
  77
  78        return 0;
  79}
  80
  81/*
  82 * v4l2 ioctl call backs.
  83 * we are just a wrapper for v4l2_sub_devs.
  84 */
  85static inline struct v4l2_device *get_v4l2_dev(struct file *file)
  86{
  87        return &((struct radio_si4713_device *)video_drvdata(file))->v4l2_dev;
  88}
  89
  90static int radio_si4713_g_modulator(struct file *file, void *p,
  91                                    struct v4l2_modulator *vm)
  92{
  93        return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
  94                                          g_modulator, vm);
  95}
  96
  97static int radio_si4713_s_modulator(struct file *file, void *p,
  98                                    const struct v4l2_modulator *vm)
  99{
 100        return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
 101                                          s_modulator, vm);
 102}
 103
 104static int radio_si4713_g_frequency(struct file *file, void *p,
 105                                    struct v4l2_frequency *vf)
 106{
 107        return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
 108                                          g_frequency, vf);
 109}
 110
 111static int radio_si4713_s_frequency(struct file *file, void *p,
 112                                    const struct v4l2_frequency *vf)
 113{
 114        return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
 115                                          s_frequency, vf);
 116}
 117
 118static long radio_si4713_default(struct file *file, void *p,
 119                                 bool valid_prio, unsigned int cmd, void *arg)
 120{
 121        return v4l2_device_call_until_err(get_v4l2_dev(file), 0, core,
 122                                          ioctl, cmd, arg);
 123}
 124
 125static struct v4l2_ioctl_ops radio_si4713_ioctl_ops = {
 126        .vidioc_querycap        = radio_si4713_querycap,
 127        .vidioc_g_modulator     = radio_si4713_g_modulator,
 128        .vidioc_s_modulator     = radio_si4713_s_modulator,
 129        .vidioc_g_frequency     = radio_si4713_g_frequency,
 130        .vidioc_s_frequency     = radio_si4713_s_frequency,
 131        .vidioc_log_status      = v4l2_ctrl_log_status,
 132        .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 133        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 134        .vidioc_default         = radio_si4713_default,
 135};
 136
 137/* radio_si4713_vdev_template - video device interface */
 138static const struct video_device radio_si4713_vdev_template = {
 139        .fops                   = &radio_si4713_fops,
 140        .name                   = "radio-si4713",
 141        .release                = video_device_release_empty,
 142        .ioctl_ops              = &radio_si4713_ioctl_ops,
 143        .vfl_dir                = VFL_DIR_TX,
 144};
 145
 146/* Platform driver interface */
 147/* radio_si4713_pdriver_probe - probe for the device */
 148static int radio_si4713_pdriver_probe(struct platform_device *pdev)
 149{
 150        struct radio_si4713_platform_data *pdata = pdev->dev.platform_data;
 151        struct radio_si4713_device *rsdev;
 152        struct v4l2_subdev *sd;
 153        int rval = 0;
 154
 155        if (!pdata) {
 156                dev_err(&pdev->dev, "Cannot proceed without platform data.\n");
 157                rval = -EINVAL;
 158                goto exit;
 159        }
 160
 161        rsdev = devm_kzalloc(&pdev->dev, sizeof(*rsdev), GFP_KERNEL);
 162        if (!rsdev) {
 163                dev_err(&pdev->dev, "Failed to alloc video device.\n");
 164                rval = -ENOMEM;
 165                goto exit;
 166        }
 167        mutex_init(&rsdev->lock);
 168
 169        rval = v4l2_device_register(&pdev->dev, &rsdev->v4l2_dev);
 170        if (rval) {
 171                dev_err(&pdev->dev, "Failed to register v4l2 device.\n");
 172                goto exit;
 173        }
 174
 175        sd = i2c_get_clientdata(pdata->subdev);
 176        rval = v4l2_device_register_subdev(&rsdev->v4l2_dev, sd);
 177        if (rval) {
 178                dev_err(&pdev->dev, "Cannot get v4l2 subdevice\n");
 179                goto unregister_v4l2_dev;
 180        }
 181
 182        rsdev->radio_dev = radio_si4713_vdev_template;
 183        rsdev->radio_dev.v4l2_dev = &rsdev->v4l2_dev;
 184        rsdev->radio_dev.ctrl_handler = sd->ctrl_handler;
 185        /* Serialize all access to the si4713 */
 186        rsdev->radio_dev.lock = &rsdev->lock;
 187        video_set_drvdata(&rsdev->radio_dev, rsdev);
 188        if (video_register_device(&rsdev->radio_dev, VFL_TYPE_RADIO, radio_nr)) {
 189                dev_err(&pdev->dev, "Could not register video device.\n");
 190                rval = -EIO;
 191                goto unregister_v4l2_dev;
 192        }
 193        dev_info(&pdev->dev, "New device successfully probed\n");
 194
 195        goto exit;
 196
 197unregister_v4l2_dev:
 198        v4l2_device_unregister(&rsdev->v4l2_dev);
 199exit:
 200        return rval;
 201}
 202
 203/* radio_si4713_pdriver_remove - remove the device */
 204static int radio_si4713_pdriver_remove(struct platform_device *pdev)
 205{
 206        struct v4l2_device *v4l2_dev = platform_get_drvdata(pdev);
 207        struct radio_si4713_device *rsdev;
 208
 209        rsdev = container_of(v4l2_dev, struct radio_si4713_device, v4l2_dev);
 210        video_unregister_device(&rsdev->radio_dev);
 211        v4l2_device_unregister(&rsdev->v4l2_dev);
 212
 213        return 0;
 214}
 215
 216static struct platform_driver radio_si4713_pdriver = {
 217        .driver         = {
 218                .name   = "radio-si4713",
 219        },
 220        .probe          = radio_si4713_pdriver_probe,
 221        .remove         = radio_si4713_pdriver_remove,
 222};
 223
 224module_platform_driver(radio_si4713_pdriver);
 225