drivers/media/radio/dsbr100.c

   1 /* A driver for the D-Link DSB-R100 USB radio and Gemtek USB Radio 21.
   2  * The device plugs into both the USB and an analog audio input, so this thing
   3  * only deals with initialisation and frequency setting, the
   4  * audio data has to be handled by a sound driver.
   5  *
   6  * Major issue: I can't find out where the device reports the signal
   7  * strength, and indeed the windows software appearantly just looks
   8  * at the stereo indicator as well.  So, scanning will only find
   9  * stereo stations.  Sad, but I can't help it.
  10  *
  11  * Also, the windows program sends oodles of messages over to the
  12  * device, and I couldn't figure out their meaning.  My suspicion
  13  * is that they don't have any:-)
  14  *
  15  * You might find some interesting stuff about this module at
  16  * http://unimut.fsk.uni-heidelberg.de/unimut/demi/dsbr
  17  *
  18  * Fully tested with the Keene USB FM Transmitter and the v4l2-compliance tool.
  19  *
  20  * Copyright (c) 2000 Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
  21  *
  22  * This program is free software; you can redistribute it and/or modify
  23  * it under the terms of the GNU General Public License as published by
  24  * the Free Software Foundation; either version 2 of the License, or
  25  * (at your option) any later version.
  26  *
  27  * This program is distributed in the hope that it will be useful,
  28  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  29  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  30  * GNU General Public License for more details.
  31 */
  32
  33 #include <linux/kernel.h>
  34 #include <linux/module.h>
  35 #include <linux/init.h>
  36 #include <linux/slab.h>
  37 #include <linux/input.h>
  38 #include <linux/videodev2.h>
  39 #include <linux/usb.h>
  40 #include <media/v4l2-device.h>
  41 #include <media/v4l2-ioctl.h>
  42 #include <media/v4l2-ctrls.h>
  43 #include <media/v4l2-event.h>
  44
  45 /*
  46  * Version Information
  47  */
  48 MODULE_AUTHOR("Markus Demleitner <msdemlei@tucana.harvard.edu>");
  49 MODULE_DESCRIPTION("D-Link DSB-R100 USB FM radio driver");
  50 MODULE_LICENSE("GPL");
  51 MODULE_VERSION("1.1.0");
  52
  53 #define DSB100_VENDOR 0x04b4
  54 #define DSB100_PRODUCT 0x1002
  55
  56 /* Commands the device appears to understand */
  57 #define DSB100_TUNE 1
  58 #define DSB100_ONOFF 2
  59
  60 #define TB_LEN 16
  61
  62 /* Frequency limits in MHz -- these are European values.  For Japanese
  63 devices, that would be 76 and 91.  */
  64 #define FREQ_MIN  87.5
  65 #define FREQ_MAX 108.0
  66 #define FREQ_MUL 16000
  67
  68 #define v4l2_dev_to_radio(d) container_of(d, struct dsbr100_device, v4l2_dev)
  69
  70 static int radio_nr = -1;
  71 module_param(radio_nr, int, 0);
  72
  73 /* Data for one (physical) device */
  74 struct dsbr100_device {
  75         struct usb_device *usbdev;
  76         struct video_device videodev;
  77         struct v4l2_device v4l2_dev;
  78         struct v4l2_ctrl_handler hdl;
  79
  80         u8 *transfer_buffer;
  81         struct mutex v4l2_lock;
  82         int curfreq;
  83         bool stereo;
  84         bool muted;
  85 };
  86
  87 /* Low-level device interface begins here */
  88
  89 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
  90 static int dsbr100_setfreq(struct dsbr100_device *radio, unsigned freq)
  91 {
  92         unsigned f = (freq / 16 * 80) / 1000 + 856;
  93         int retval = 0;
  94
  95         if (!radio->muted) {
  96                 retval = usb_control_msg(radio->usbdev,
  97                                 usb_rcvctrlpipe(radio->usbdev, 0),
  98                                 DSB100_TUNE,
  99                                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 100                                 (f >> 8) & 0x00ff, f & 0xff,
 101                                 radio->transfer_buffer, 8, 300);
 102                 if (retval >= 0)
 103                         mdelay(1);
 104         }
 105
 106         if (retval >= 0) {
 107                 radio->curfreq = freq;
 108                 return 0;
 109         }
 110         dev_err(&radio->usbdev->dev,
 111                 "%s - usb_control_msg returned %i, request %i\n",
 112                         __func__, retval, DSB100_TUNE);
 113         return retval;
 114 }
 115
 116 /* switch on radio */
 117 static int dsbr100_start(struct dsbr100_device *radio)
 118 {
 119         int retval = usb_control_msg(radio->usbdev,
 120                 usb_rcvctrlpipe(radio->usbdev, 0),
 121                 DSB100_ONOFF,
 122                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 123                 0x01, 0x00, radio->transfer_buffer, 8, 300);
 124
 125         if (retval >= 0)
 126                 return dsbr100_setfreq(radio, radio->curfreq);
 127         dev_err(&radio->usbdev->dev,
 128                 "%s - usb_control_msg returned %i, request %i\n",
 129                         __func__, retval, DSB100_ONOFF);
 130         return retval;
 131
 132 }
 133
 134 /* switch off radio */
 135 static int dsbr100_stop(struct dsbr100_device *radio)
 136 {
 137         int retval = usb_control_msg(radio->usbdev,
 138                 usb_rcvctrlpipe(radio->usbdev, 0),
 139                 DSB100_ONOFF,
 140                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 141                 0x00, 0x00, radio->transfer_buffer, 8, 300);
 142
 143         if (retval >= 0)
 144                 return 0;
 145         dev_err(&radio->usbdev->dev,
 146                 "%s - usb_control_msg returned %i, request %i\n",
 147                         __func__, retval, DSB100_ONOFF);
 148         return retval;
 149
 150 }
 151
 152 /* return the device status.  This is, in effect, just whether it
 153 sees a stereo signal or not.  Pity. */
 154 static void dsbr100_getstat(struct dsbr100_device *radio)
 155 {
 156         int retval = usb_control_msg(radio->usbdev,
 157                 usb_rcvctrlpipe(radio->usbdev, 0),
 158                 USB_REQ_GET_STATUS,
 159                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 160                 0x00, 0x24, radio->transfer_buffer, 8, 300);
 161
 162         if (retval < 0) {
 163                 radio->stereo = false;
 164                 dev_err(&radio->usbdev->dev,
 165                         "%s - usb_control_msg returned %i, request %i\n",
 166                                 __func__, retval, USB_REQ_GET_STATUS);
 167         } else {
 168                 radio->stereo = !(radio->transfer_buffer[0] & 0x01);
 169         }
 170 }
 171
 172 static int vidioc_querycap(struct file *file, void *priv,
 173                                         struct v4l2_capability *v)
 174 {
 175         struct dsbr100_device *radio = video_drvdata(file);
 176
 177         strlcpy(v->driver, "dsbr100", sizeof(v->driver));
 178         strlcpy(v->card, "D-Link R-100 USB FM Radio", sizeof(v->card));
 179         usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
 180         v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
 181         v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 182         return 0;
 183 }
 184
 185 static int vidioc_g_tuner(struct file *file, void *priv,
 186                                 struct v4l2_tuner *v)
 187 {
 188         struct dsbr100_device *radio = video_drvdata(file);
 189
 190         if (v->index > 0)
 191                 return -EINVAL;
 192
 193         dsbr100_getstat(radio);
 194         strcpy(v->name, "FM");
 195         v->type = V4L2_TUNER_RADIO;
 196         v->rangelow = FREQ_MIN * FREQ_MUL;
 197         v->rangehigh = FREQ_MAX * FREQ_MUL;
 198         v->rxsubchans = radio->stereo ? V4L2_TUNER_SUB_STEREO :
 199                 V4L2_TUNER_SUB_MONO;
 200         v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 201         v->audmode = V4L2_TUNER_MODE_STEREO;
 202         v->signal = radio->stereo ? 0xffff : 0;     /* We can't get the signal strength */
 203         return 0;
 204 }
 205
 206 static int vidioc_s_tuner(struct file *file, void *priv,
 207                                 const struct v4l2_tuner *v)
 208 {
 209         return v->index ? -EINVAL : 0;
 210 }
 211
 212 static int vidioc_s_frequency(struct file *file, void *priv,
 213                                 const struct v4l2_frequency *f)
 214 {
 215         struct dsbr100_device *radio = video_drvdata(file);
 216
 217         if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
 218                 return -EINVAL;
 219
 220         return dsbr100_setfreq(radio, clamp_t(unsigned, f->frequency,
 221                         FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
 222 }
 223
 224 static int vidioc_g_frequency(struct file *file, void *priv,
 225                                 struct v4l2_frequency *f)
 226 {
 227         struct dsbr100_device *radio = video_drvdata(file);
 228
 229         if (f->tuner)
 230                 return -EINVAL;
 231         f->type = V4L2_TUNER_RADIO;
 232         f->frequency = radio->curfreq;
 233         return 0;
 234 }
 235
 236 static int usb_dsbr100_s_ctrl(struct v4l2_ctrl *ctrl)
 237 {
 238         struct dsbr100_device *radio =
 239                 container_of(ctrl->handler, struct dsbr100_device, hdl);
 240
 241         switch (ctrl->id) {
 242         case V4L2_CID_AUDIO_MUTE:
 243                 radio->muted = ctrl->val;
 244                 return radio->muted ? dsbr100_stop(radio) : dsbr100_start(radio);
 245         }
 246         return -EINVAL;
 247 }
 248
 249
 250 /* USB subsystem interface begins here */
 251
 252 /*
 253  * Handle unplugging of the device.
 254  * We call video_unregister_device in any case.
 255  * The last function called in this procedure is
 256  * usb_dsbr100_video_device_release
 257  */
 258 static void usb_dsbr100_disconnect(struct usb_interface *intf)
 259 {
 260         struct dsbr100_device *radio = usb_get_intfdata(intf);
 261
 262         mutex_lock(&radio->v4l2_lock);
 263         /*
 264          * Disconnect is also called on unload, and in that case we need to
 265          * mute the device. This call will silently fail if it is called
 266          * after a physical disconnect.
 267          */
 268         usb_control_msg(radio->usbdev,
 269                 usb_rcvctrlpipe(radio->usbdev, 0),
 270                 DSB100_ONOFF,
 271                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 272                 0x00, 0x00, radio->transfer_buffer, 8, 300);
 273         usb_set_intfdata(intf, NULL);
 274         video_unregister_device(&radio->videodev);
 275         v4l2_device_disconnect(&radio->v4l2_dev);
 276         mutex_unlock(&radio->v4l2_lock);
 277         v4l2_device_put(&radio->v4l2_dev);
 278 }
 279
 280
 281 /* Suspend device - stop device. */
 282 static int usb_dsbr100_suspend(struct usb_interface *intf, pm_message_t message)
 283 {
 284         struct dsbr100_device *radio = usb_get_intfdata(intf);
 285
 286         mutex_lock(&radio->v4l2_lock);
 287         if (!radio->muted && dsbr100_stop(radio) < 0)
 288                 dev_warn(&intf->dev, "dsbr100_stop failed\n");
 289         mutex_unlock(&radio->v4l2_lock);
 290
 291         dev_info(&intf->dev, "going into suspend..\n");
 292         return 0;
 293 }
 294
 295 /* Resume device - start device. */
 296 static int usb_dsbr100_resume(struct usb_interface *intf)
 297 {
 298         struct dsbr100_device *radio = usb_get_intfdata(intf);
 299
 300         mutex_lock(&radio->v4l2_lock);
 301         if (!radio->muted && dsbr100_start(radio) < 0)
 302                 dev_warn(&intf->dev, "dsbr100_start failed\n");
 303         mutex_unlock(&radio->v4l2_lock);
 304
 305         dev_info(&intf->dev, "coming out of suspend..\n");
 306         return 0;
 307 }
 308
 309 /* free data structures */
 310 static void usb_dsbr100_release(struct v4l2_device *v4l2_dev)
 311 {
 312         struct dsbr100_device *radio = v4l2_dev_to_radio(v4l2_dev);
 313
 314         v4l2_ctrl_handler_free(&radio->hdl);
 315         v4l2_device_unregister(&radio->v4l2_dev);
 316         kfree(radio->transfer_buffer);
 317         kfree(radio);
 318 }
 319
 320 static const struct v4l2_ctrl_ops usb_dsbr100_ctrl_ops = {
 321         .s_ctrl = usb_dsbr100_s_ctrl,
 322 };
 323
 324 /* File system interface */
 325 static const struct v4l2_file_operations usb_dsbr100_fops = {
 326         .owner          = THIS_MODULE,
 327         .unlocked_ioctl = video_ioctl2,
 328         .open           = v4l2_fh_open,
 329         .release        = v4l2_fh_release,
 330         .poll           = v4l2_ctrl_poll,
 331 };
 332
 333 static const struct v4l2_ioctl_ops usb_dsbr100_ioctl_ops = {
 334         .vidioc_querycap    = vidioc_querycap,
 335         .vidioc_g_tuner     = vidioc_g_tuner,
 336         .vidioc_s_tuner     = vidioc_s_tuner,
 337         .vidioc_g_frequency = vidioc_g_frequency,
 338         .vidioc_s_frequency = vidioc_s_frequency,
 339         .vidioc_log_status  = v4l2_ctrl_log_status,
 340         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 341         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 342 };
 343
 344 /* check if the device is present and register with v4l and usb if it is */
 345 static int usb_dsbr100_probe(struct usb_interface *intf,
 346                                 const struct usb_device_id *id)
 347 {
 348         struct dsbr100_device *radio;
 349         struct v4l2_device *v4l2_dev;
 350         int retval;
 351
 352         radio = kzalloc(sizeof(struct dsbr100_device), GFP_KERNEL);
 353
 354         if (!radio)
 355                 return -ENOMEM;
 356
 357         radio->transfer_buffer = kmalloc(TB_LEN, GFP_KERNEL);
 358
 359         if (!(radio->transfer_buffer)) {
 360                 kfree(radio);
 361                 return -ENOMEM;
 362         }
 363
 364         v4l2_dev = &radio->v4l2_dev;
 365         v4l2_dev->release = usb_dsbr100_release;
 366
 367         retval = v4l2_device_register(&intf->dev, v4l2_dev);
 368         if (retval < 0) {
 369                 v4l2_err(v4l2_dev, "couldn't register v4l2_device\n");
 370                 goto err_reg_dev;
 371         }
 372
 373         v4l2_ctrl_handler_init(&radio->hdl, 1);
 374         v4l2_ctrl_new_std(&radio->hdl, &usb_dsbr100_ctrl_ops,
 375                           V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 376         if (radio->hdl.error) {
 377                 retval = radio->hdl.error;
 378                 v4l2_err(v4l2_dev, "couldn't register control\n");
 379                 goto err_reg_ctrl;
 380         }
 381         mutex_init(&radio->v4l2_lock);
 382         strlcpy(radio->videodev.name, v4l2_dev->name, sizeof(radio->videodev.name));
 383         radio->videodev.v4l2_dev = v4l2_dev;
 384         radio->videodev.fops = &usb_dsbr100_fops;
 385         radio->videodev.ioctl_ops = &usb_dsbr100_ioctl_ops;
 386         radio->videodev.release = video_device_release_empty;
 387         radio->videodev.lock = &radio->v4l2_lock;
 388         radio->videodev.ctrl_handler = &radio->hdl;
 389
 390         radio->usbdev = interface_to_usbdev(intf);
 391         radio->curfreq = FREQ_MIN * FREQ_MUL;
 392         radio->muted = true;
 393
 394         video_set_drvdata(&radio->videodev, radio);
 395         usb_set_intfdata(intf, radio);
 396
 397         retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO, radio_nr);
 398         if (retval == 0)
 399                 return 0;
 400         v4l2_err(v4l2_dev, "couldn't register video device\n");
 401
 402 err_reg_ctrl:
 403         v4l2_ctrl_handler_free(&radio->hdl);
 404         v4l2_device_unregister(v4l2_dev);
 405 err_reg_dev:
 406         kfree(radio->transfer_buffer);
 407         kfree(radio);
 408         return retval;
 409 }
 410
 411 static const struct usb_device_id usb_dsbr100_device_table[] = {
 412         { USB_DEVICE(DSB100_VENDOR, DSB100_PRODUCT) },
 413         { }                                             /* Terminating entry */
 414 };
 415
 416 MODULE_DEVICE_TABLE(usb, usb_dsbr100_device_table);
 417
 418 /* USB subsystem interface */
 419 static struct usb_driver usb_dsbr100_driver = {
 420         .name                   = "dsbr100",
 421         .probe                  = usb_dsbr100_probe,
 422         .disconnect             = usb_dsbr100_disconnect,
 423         .id_table               = usb_dsbr100_device_table,
 424         .suspend                = usb_dsbr100_suspend,
 425         .resume                 = usb_dsbr100_resume,
 426         .reset_resume           = usb_dsbr100_resume,
 427 };
 428
 429 module_usb_driver(usb_dsbr100_driver);