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  * You should have received a copy of the GNU General Public License
  33  * along with this program; if not, write to the Free Software
  34  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  35 */
  36
  37 #include <linux/kernel.h>
  38 #include <linux/module.h>
  39 #include <linux/init.h>
  40 #include <linux/slab.h>
  41 #include <linux/input.h>
  42 #include <linux/videodev2.h>
  43 #include <linux/usb.h>
  44 #include <media/v4l2-device.h>
  45 #include <media/v4l2-ioctl.h>
  46 #include <media/v4l2-ctrls.h>
  47 #include <media/v4l2-event.h>
  48
  49 /*
  50  * Version Information
  51  */
  52 MODULE_AUTHOR("Markus Demleitner <msdemlei@tucana.harvard.edu>");
  53 MODULE_DESCRIPTION("D-Link DSB-R100 USB FM radio driver");
  54 MODULE_LICENSE("GPL");
  55 MODULE_VERSION("1.1.0");
  56
  57 #define DSB100_VENDOR 0x04b4
  58 #define DSB100_PRODUCT 0x1002
  59
  60 /* Commands the device appears to understand */
  61 #define DSB100_TUNE 1
  62 #define DSB100_ONOFF 2
  63
  64 #define TB_LEN 16
  65
  66 /* Frequency limits in MHz -- these are European values.  For Japanese
  67 devices, that would be 76 and 91.  */
  68 #define FREQ_MIN  87.5
  69 #define FREQ_MAX 108.0
  70 #define FREQ_MUL 16000
  71
  72 #define v4l2_dev_to_radio(d) container_of(d, struct dsbr100_device, v4l2_dev)
  73
  74 static int radio_nr = -1;
  75 module_param(radio_nr, int, 0);
  76
  77 /* Data for one (physical) device */
  78 struct dsbr100_device {
  79         struct usb_device *usbdev;
  80         struct video_device videodev;
  81         struct v4l2_device v4l2_dev;
  82         struct v4l2_ctrl_handler hdl;
  83
  84         u8 *transfer_buffer;
  85         struct mutex v4l2_lock;
  86         int curfreq;
  87         bool stereo;
  88         bool muted;
  89 };
  90
  91 /* Low-level device interface begins here */
  92
  93 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
  94 static int dsbr100_setfreq(struct dsbr100_device *radio, unsigned freq)
  95 {
  96         unsigned f = (freq / 16 * 80) / 1000 + 856;
  97         int retval = 0;
  98
  99         if (!radio->muted) {
 100                 retval = usb_control_msg(radio->usbdev,
 101                                 usb_rcvctrlpipe(radio->usbdev, 0),
 102                                 DSB100_TUNE,
 103                                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 104                                 (f >> 8) & 0x00ff, f & 0xff,
 105                                 radio->transfer_buffer, 8, 300);
 106                 if (retval >= 0)
 107                         mdelay(1);
 108         }
 109
 110         if (retval >= 0) {
 111                 radio->curfreq = freq;
 112                 return 0;
 113         }
 114         dev_err(&radio->usbdev->dev,
 115                 "%s - usb_control_msg returned %i, request %i\n",
 116                         __func__, retval, DSB100_TUNE);
 117         return retval;
 118 }
 119
 120 /* switch on radio */
 121 static int dsbr100_start(struct dsbr100_device *radio)
 122 {
 123         int retval = usb_control_msg(radio->usbdev,
 124                 usb_rcvctrlpipe(radio->usbdev, 0),
 125                 DSB100_ONOFF,
 126                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 127                 0x01, 0x00, radio->transfer_buffer, 8, 300);
 128
 129         if (retval >= 0)
 130                 return dsbr100_setfreq(radio, radio->curfreq);
 131         dev_err(&radio->usbdev->dev,
 132                 "%s - usb_control_msg returned %i, request %i\n",
 133                         __func__, retval, DSB100_ONOFF);
 134         return retval;
 135
 136 }
 137
 138 /* switch off radio */
 139 static int dsbr100_stop(struct dsbr100_device *radio)
 140 {
 141         int retval = usb_control_msg(radio->usbdev,
 142                 usb_rcvctrlpipe(radio->usbdev, 0),
 143                 DSB100_ONOFF,
 144                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 145                 0x00, 0x00, radio->transfer_buffer, 8, 300);
 146
 147         if (retval >= 0)
 148                 return 0;
 149         dev_err(&radio->usbdev->dev,
 150                 "%s - usb_control_msg returned %i, request %i\n",
 151                         __func__, retval, DSB100_ONOFF);
 152         return retval;
 153
 154 }
 155
 156 /* return the device status.  This is, in effect, just whether it
 157 sees a stereo signal or not.  Pity. */
 158 static void dsbr100_getstat(struct dsbr100_device *radio)
 159 {
 160         int retval = usb_control_msg(radio->usbdev,
 161                 usb_rcvctrlpipe(radio->usbdev, 0),
 162                 USB_REQ_GET_STATUS,
 163                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 164                 0x00, 0x24, radio->transfer_buffer, 8, 300);
 165
 166         if (retval < 0) {
 167                 radio->stereo = false;
 168                 dev_err(&radio->usbdev->dev,
 169                         "%s - usb_control_msg returned %i, request %i\n",
 170                                 __func__, retval, USB_REQ_GET_STATUS);
 171         } else {
 172                 radio->stereo = !(radio->transfer_buffer[0] & 0x01);
 173         }
 174 }
 175
 176 static int vidioc_querycap(struct file *file, void *priv,
 177                                         struct v4l2_capability *v)
 178 {
 179         struct dsbr100_device *radio = video_drvdata(file);
 180
 181         strlcpy(v->driver, "dsbr100", sizeof(v->driver));
 182         strlcpy(v->card, "D-Link R-100 USB FM Radio", sizeof(v->card));
 183         usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
 184         v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
 185         v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 186         return 0;
 187 }
 188
 189 static int vidioc_g_tuner(struct file *file, void *priv,
 190                                 struct v4l2_tuner *v)
 191 {
 192         struct dsbr100_device *radio = video_drvdata(file);
 193
 194         if (v->index > 0)
 195                 return -EINVAL;
 196
 197         dsbr100_getstat(radio);
 198         strcpy(v->name, "FM");
 199         v->type = V4L2_TUNER_RADIO;
 200         v->rangelow = FREQ_MIN * FREQ_MUL;
 201         v->rangehigh = FREQ_MAX * FREQ_MUL;
 202         v->rxsubchans = radio->stereo ? V4L2_TUNER_SUB_STEREO :
 203                 V4L2_TUNER_SUB_MONO;
 204         v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 205         v->audmode = V4L2_TUNER_MODE_STEREO;
 206         v->signal = radio->stereo ? 0xffff : 0;     /* We can't get the signal strength */
 207         return 0;
 208 }
 209
 210 static int vidioc_s_tuner(struct file *file, void *priv,
 211                                 const struct v4l2_tuner *v)
 212 {
 213         return v->index ? -EINVAL : 0;
 214 }
 215
 216 static int vidioc_s_frequency(struct file *file, void *priv,
 217                                 const struct v4l2_frequency *f)
 218 {
 219         struct dsbr100_device *radio = video_drvdata(file);
 220
 221         if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
 222                 return -EINVAL;
 223
 224         return dsbr100_setfreq(radio, clamp_t(unsigned, f->frequency,
 225                         FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
 226 }
 227
 228 static int vidioc_g_frequency(struct file *file, void *priv,
 229                                 struct v4l2_frequency *f)
 230 {
 231         struct dsbr100_device *radio = video_drvdata(file);
 232
 233         if (f->tuner)
 234                 return -EINVAL;
 235         f->type = V4L2_TUNER_RADIO;
 236         f->frequency = radio->curfreq;
 237         return 0;
 238 }
 239
 240 static int usb_dsbr100_s_ctrl(struct v4l2_ctrl *ctrl)
 241 {
 242         struct dsbr100_device *radio =
 243                 container_of(ctrl->handler, struct dsbr100_device, hdl);
 244
 245         switch (ctrl->id) {
 246         case V4L2_CID_AUDIO_MUTE:
 247                 radio->muted = ctrl->val;
 248                 return radio->muted ? dsbr100_stop(radio) : dsbr100_start(radio);
 249         }
 250         return -EINVAL;
 251 }
 252
 253
 254 /* USB subsystem interface begins here */
 255
 256 /*
 257  * Handle unplugging of the device.
 258  * We call video_unregister_device in any case.
 259  * The last function called in this procedure is
 260  * usb_dsbr100_video_device_release
 261  */
 262 static void usb_dsbr100_disconnect(struct usb_interface *intf)
 263 {
 264         struct dsbr100_device *radio = usb_get_intfdata(intf);
 265
 266         mutex_lock(&radio->v4l2_lock);
 267         /*
 268          * Disconnect is also called on unload, and in that case we need to
 269          * mute the device. This call will silently fail if it is called
 270          * after a physical disconnect.
 271          */
 272         usb_control_msg(radio->usbdev,
 273                 usb_rcvctrlpipe(radio->usbdev, 0),
 274                 DSB100_ONOFF,
 275                 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 276                 0x00, 0x00, radio->transfer_buffer, 8, 300);
 277         usb_set_intfdata(intf, NULL);
 278         video_unregister_device(&radio->videodev);
 279         v4l2_device_disconnect(&radio->v4l2_dev);
 280         mutex_unlock(&radio->v4l2_lock);
 281         v4l2_device_put(&radio->v4l2_dev);
 282 }
 283
 284
 285 /* Suspend device - stop device. */
 286 static int usb_dsbr100_suspend(struct usb_interface *intf, pm_message_t message)
 287 {
 288         struct dsbr100_device *radio = usb_get_intfdata(intf);
 289
 290         mutex_lock(&radio->v4l2_lock);
 291         if (!radio->muted && dsbr100_stop(radio) < 0)
 292                 dev_warn(&intf->dev, "dsbr100_stop failed\n");
 293         mutex_unlock(&radio->v4l2_lock);
 294
 295         dev_info(&intf->dev, "going into suspend..\n");
 296         return 0;
 297 }
 298
 299 /* Resume device - start device. */
 300 static int usb_dsbr100_resume(struct usb_interface *intf)
 301 {
 302         struct dsbr100_device *radio = usb_get_intfdata(intf);
 303
 304         mutex_lock(&radio->v4l2_lock);
 305         if (!radio->muted && dsbr100_start(radio) < 0)
 306                 dev_warn(&intf->dev, "dsbr100_start failed\n");
 307         mutex_unlock(&radio->v4l2_lock);
 308
 309         dev_info(&intf->dev, "coming out of suspend..\n");
 310         return 0;
 311 }
 312
 313 /* free data structures */
 314 static void usb_dsbr100_release(struct v4l2_device *v4l2_dev)
 315 {
 316         struct dsbr100_device *radio = v4l2_dev_to_radio(v4l2_dev);
 317
 318         v4l2_ctrl_handler_free(&radio->hdl);
 319         v4l2_device_unregister(&radio->v4l2_dev);
 320         kfree(radio->transfer_buffer);
 321         kfree(radio);
 322 }
 323
 324 static const struct v4l2_ctrl_ops usb_dsbr100_ctrl_ops = {
 325         .s_ctrl = usb_dsbr100_s_ctrl,
 326 };
 327
 328 /* File system interface */
 329 static const struct v4l2_file_operations usb_dsbr100_fops = {
 330         .owner          = THIS_MODULE,
 331         .unlocked_ioctl = video_ioctl2,
 332         .open           = v4l2_fh_open,
 333         .release        = v4l2_fh_release,
 334         .poll           = v4l2_ctrl_poll,
 335 };
 336
 337 static const struct v4l2_ioctl_ops usb_dsbr100_ioctl_ops = {
 338         .vidioc_querycap    = vidioc_querycap,
 339         .vidioc_g_tuner     = vidioc_g_tuner,
 340         .vidioc_s_tuner     = vidioc_s_tuner,
 341         .vidioc_g_frequency = vidioc_g_frequency,
 342         .vidioc_s_frequency = vidioc_s_frequency,
 343         .vidioc_log_status  = v4l2_ctrl_log_status,
 344         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 345         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 346 };
 347
 348 /* check if the device is present and register with v4l and usb if it is */
 349 static int usb_dsbr100_probe(struct usb_interface *intf,
 350                                 const struct usb_device_id *id)
 351 {
 352         struct dsbr100_device *radio;
 353         struct v4l2_device *v4l2_dev;
 354         int retval;
 355
 356         radio = kzalloc(sizeof(struct dsbr100_device), GFP_KERNEL);
 357
 358         if (!radio)
 359                 return -ENOMEM;
 360
 361         radio->transfer_buffer = kmalloc(TB_LEN, GFP_KERNEL);
 362
 363         if (!(radio->transfer_buffer)) {
 364                 kfree(radio);
 365                 return -ENOMEM;
 366         }
 367
 368         v4l2_dev = &radio->v4l2_dev;
 369         v4l2_dev->release = usb_dsbr100_release;
 370
 371         retval = v4l2_device_register(&intf->dev, v4l2_dev);
 372         if (retval < 0) {
 373                 v4l2_err(v4l2_dev, "couldn't register v4l2_device\n");
 374                 goto err_reg_dev;
 375         }
 376
 377         v4l2_ctrl_handler_init(&radio->hdl, 1);
 378         v4l2_ctrl_new_std(&radio->hdl, &usb_dsbr100_ctrl_ops,
 379                           V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 380         if (radio->hdl.error) {
 381                 retval = radio->hdl.error;
 382                 v4l2_err(v4l2_dev, "couldn't register control\n");
 383                 goto err_reg_ctrl;
 384         }
 385         mutex_init(&radio->v4l2_lock);
 386         strlcpy(radio->videodev.name, v4l2_dev->name, sizeof(radio->videodev.name));
 387         radio->videodev.v4l2_dev = v4l2_dev;
 388         radio->videodev.fops = &usb_dsbr100_fops;
 389         radio->videodev.ioctl_ops = &usb_dsbr100_ioctl_ops;
 390         radio->videodev.release = video_device_release_empty;
 391         radio->videodev.lock = &radio->v4l2_lock;
 392         radio->videodev.ctrl_handler = &radio->hdl;
 393
 394         radio->usbdev = interface_to_usbdev(intf);
 395         radio->curfreq = FREQ_MIN * FREQ_MUL;
 396         radio->muted = true;
 397
 398         video_set_drvdata(&radio->videodev, radio);
 399         usb_set_intfdata(intf, radio);
 400
 401         retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO, radio_nr);
 402         if (retval == 0)
 403                 return 0;
 404         v4l2_err(v4l2_dev, "couldn't register video device\n");
 405
 406 err_reg_ctrl:
 407         v4l2_ctrl_handler_free(&radio->hdl);
 408         v4l2_device_unregister(v4l2_dev);
 409 err_reg_dev:
 410         kfree(radio->transfer_buffer);
 411         kfree(radio);
 412         return retval;
 413 }
 414
 415 static struct usb_device_id usb_dsbr100_device_table[] = {
 416         { USB_DEVICE(DSB100_VENDOR, DSB100_PRODUCT) },
 417         { }                                             /* Terminating entry */
 418 };
 419
 420 MODULE_DEVICE_TABLE(usb, usb_dsbr100_device_table);
 421
 422 /* USB subsystem interface */
 423 static struct usb_driver usb_dsbr100_driver = {
 424         .name                   = "dsbr100",
 425         .probe                  = usb_dsbr100_probe,
 426         .disconnect             = usb_dsbr100_disconnect,
 427         .id_table               = usb_dsbr100_device_table,
 428         .suspend                = usb_dsbr100_suspend,
 429         .resume                 = usb_dsbr100_resume,
 430         .reset_resume           = usb_dsbr100_resume,
 431 };
 432
 433 module_usb_driver(usb_dsbr100_driver);