drivers/media/radio/si4713/radio-platform-si4713.c

   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 */
  36 static int radio_nr = -1;       /* radio device minor (-1 ==> auto assign) */
  37 module_param(radio_nr, int, 0);
  38 MODULE_PARM_DESC(radio_nr,
  39                  "Minor number for radio device (-1 ==> auto assign)");
  40
  41 MODULE_LICENSE("GPL v2");
  42 MODULE_AUTHOR("Eduardo Valentin <eduardo.valentin@nokia.com>");
  43 MODULE_DESCRIPTION("Platform driver for Si4713 FM Radio Transmitter");
  44 MODULE_VERSION("0.0.1");
  45 MODULE_ALIAS("platform:radio-si4713");
  46
  47 /* Driver state struct */
  48 struct 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 */
  55 static 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 */
  67 static int radio_si4713_querycap(struct file *file, void *priv,
  68                                         struct v4l2_capability *capability)
  69 {
  70         strlcpy(capability->driver, "radio-si4713", sizeof(capability->driver));
  71         strlcpy(capability->card, "Silicon Labs Si4713 Modulator",
  72                 sizeof(capability->card));
  73         strlcpy(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  */
  85 static inline struct v4l2_device *get_v4l2_dev(struct file *file)
  86 {
  87         return &((struct radio_si4713_device *)video_drvdata(file))->v4l2_dev;
  88 }
  89
  90 static 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
  97 static 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
 104 static 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
 111 static 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
 118 static 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
 125 static 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 */
 138 static 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 */
 148 static 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
 197 unregister_v4l2_dev:
 198         v4l2_device_unregister(&rsdev->v4l2_dev);
 199 exit:
 200         return rval;
 201 }
 202
 203 /* radio_si4713_pdriver_remove - remove the device */
 204 static 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
 216 static 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
 224 module_platform_driver(radio_si4713_pdriver);