drivers/media/radio/radio-ma901.c

   1 /*
   2  * Driver for the MasterKit MA901 USB FM radio. This device plugs
   3  * into the USB port and an analog audio input or headphones, so this thing
   4  * only deals with initialization, frequency setting, volume.
   5  *
   6  * Copyright (c) 2012 Alexey Klimov <klimov.linux@gmail.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/slab.h>
  27 #include <linux/input.h>
  28 #include <linux/videodev2.h>
  29 #include <media/v4l2-device.h>
  30 #include <media/v4l2-ioctl.h>
  31 #include <media/v4l2-ctrls.h>
  32 #include <media/v4l2-event.h>
  33 #include <linux/usb.h>
  34 #include <linux/mutex.h>
  35
  36 #define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
  37 #define DRIVER_DESC "Masterkit MA901 USB FM radio driver"
  38 #define DRIVER_VERSION "0.0.1"
  39
  40 MODULE_AUTHOR(DRIVER_AUTHOR);
  41 MODULE_DESCRIPTION(DRIVER_DESC);
  42 MODULE_LICENSE("GPL");
  43 MODULE_VERSION(DRIVER_VERSION);
  44
  45 #define USB_MA901_VENDOR  0x16c0
  46 #define USB_MA901_PRODUCT 0x05df
  47
  48 /* dev_warn macro with driver name */
  49 #define MA901_DRIVER_NAME "radio-ma901"
  50 #define ma901radio_dev_warn(dev, fmt, arg...)                           \
  51                 dev_warn(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
  52
  53 #define ma901radio_dev_err(dev, fmt, arg...) \
  54                 dev_err(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
  55
  56 /* Probably USB_TIMEOUT should be modified in module parameter */
  57 #define BUFFER_LENGTH 8
  58 #define USB_TIMEOUT 500
  59
  60 #define FREQ_MIN  87.5
  61 #define FREQ_MAX 108.0
  62 #define FREQ_MUL 16000
  63
  64 #define MA901_VOLUME_MAX 16
  65 #define MA901_VOLUME_MIN 0
  66
  67 /* Commands that device should understand
  68  * List isn't full and will be updated with implementation of new functions
  69  */
  70 #define MA901_RADIO_SET_FREQ            0x03
  71 #define MA901_RADIO_SET_VOLUME          0x04
  72 #define MA901_RADIO_SET_MONO_STEREO     0x05
  73
  74 /* Comfortable defines for ma901radio_set_stereo */
  75 #define MA901_WANT_STEREO               0x50
  76 #define MA901_WANT_MONO                 0xd0
  77
  78 /* module parameter */
  79 static int radio_nr = -1;
  80 module_param(radio_nr, int, 0);
  81 MODULE_PARM_DESC(radio_nr, "Radio file number");
  82
  83 /* Data for one (physical) device */
  84 struct ma901radio_device {
  85         /* reference to USB and video device */
  86         struct usb_device *usbdev;
  87         struct usb_interface *intf;
  88         struct video_device vdev;
  89         struct v4l2_device v4l2_dev;
  90         struct v4l2_ctrl_handler hdl;
  91
  92         u8 *buffer;
  93         struct mutex lock;      /* buffer locking */
  94         int curfreq;
  95         u16 volume;
  96         int stereo;
  97         bool muted;
  98 };
  99
 100 static inline struct ma901radio_device *to_ma901radio_dev(struct v4l2_device *v4l2_dev)
 101 {
 102         return container_of(v4l2_dev, struct ma901radio_device, v4l2_dev);
 103 }
 104
 105 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
 106 static int ma901radio_set_freq(struct ma901radio_device *radio, int freq)
 107 {
 108         unsigned int freq_send = 0x300 + (freq >> 5) / 25;
 109         int retval;
 110
 111         radio->buffer[0] = 0x0a;
 112         radio->buffer[1] = MA901_RADIO_SET_FREQ;
 113         radio->buffer[2] = ((freq_send >> 8) & 0xff) + 0x80;
 114         radio->buffer[3] = freq_send & 0xff;
 115         radio->buffer[4] = 0x00;
 116         radio->buffer[5] = 0x00;
 117         radio->buffer[6] = 0x00;
 118         radio->buffer[7] = 0x00;
 119
 120         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 121                                 9, 0x21, 0x0300, 0,
 122                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 123         if (retval < 0)
 124                 return retval;
 125
 126         radio->curfreq = freq;
 127         return 0;
 128 }
 129
 130 static int ma901radio_set_volume(struct ma901radio_device *radio, u16 vol_to_set)
 131 {
 132         int retval;
 133
 134         radio->buffer[0] = 0x0a;
 135         radio->buffer[1] = MA901_RADIO_SET_VOLUME;
 136         radio->buffer[2] = 0xc2;
 137         radio->buffer[3] = vol_to_set + 0x20;
 138         radio->buffer[4] = 0x00;
 139         radio->buffer[5] = 0x00;
 140         radio->buffer[6] = 0x00;
 141         radio->buffer[7] = 0x00;
 142
 143         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 144                                 9, 0x21, 0x0300, 0,
 145                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 146         if (retval < 0)
 147                 return retval;
 148
 149         radio->volume = vol_to_set;
 150         return retval;
 151 }
 152
 153 static int ma901_set_stereo(struct ma901radio_device *radio, u8 stereo)
 154 {
 155         int retval;
 156
 157         radio->buffer[0] = 0x0a;
 158         radio->buffer[1] = MA901_RADIO_SET_MONO_STEREO;
 159         radio->buffer[2] = stereo;
 160         radio->buffer[3] = 0x00;
 161         radio->buffer[4] = 0x00;
 162         radio->buffer[5] = 0x00;
 163         radio->buffer[6] = 0x00;
 164         radio->buffer[7] = 0x00;
 165
 166         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 167                                 9, 0x21, 0x0300, 0,
 168                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 169
 170         if (retval < 0)
 171                 return retval;
 172
 173         if (stereo == MA901_WANT_STEREO)
 174                 radio->stereo = V4L2_TUNER_MODE_STEREO;
 175         else
 176                 radio->stereo = V4L2_TUNER_MODE_MONO;
 177
 178         return retval;
 179 }
 180
 181 /* Handle unplugging the device.
 182  * We call video_unregister_device in any case.
 183  * The last function called in this procedure is
 184  * usb_ma901radio_device_release.
 185  */
 186 static void usb_ma901radio_disconnect(struct usb_interface *intf)
 187 {
 188         struct ma901radio_device *radio = to_ma901radio_dev(usb_get_intfdata(intf));
 189
 190         mutex_lock(&radio->lock);
 191         video_unregister_device(&radio->vdev);
 192         usb_set_intfdata(intf, NULL);
 193         v4l2_device_disconnect(&radio->v4l2_dev);
 194         mutex_unlock(&radio->lock);
 195         v4l2_device_put(&radio->v4l2_dev);
 196 }
 197
 198 /* vidioc_querycap - query device capabilities */
 199 static int vidioc_querycap(struct file *file, void *priv,
 200                                         struct v4l2_capability *v)
 201 {
 202         struct ma901radio_device *radio = video_drvdata(file);
 203
 204         strlcpy(v->driver, "radio-ma901", sizeof(v->driver));
 205         strlcpy(v->card, "Masterkit MA901 USB FM Radio", sizeof(v->card));
 206         usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
 207         v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
 208         v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 209         return 0;
 210 }
 211
 212 /* vidioc_g_tuner - get tuner attributes */
 213 static int vidioc_g_tuner(struct file *file, void *priv,
 214                                 struct v4l2_tuner *v)
 215 {
 216         struct ma901radio_device *radio = video_drvdata(file);
 217
 218         if (v->index > 0)
 219                 return -EINVAL;
 220
 221         v->signal = 0;
 222
 223         /* TODO: the same words like in _probe() goes here.
 224          * When receiving of stats will be implemented then we can call
 225          * ma901radio_get_stat().
 226          * retval = ma901radio_get_stat(radio, &is_stereo, &v->signal);
 227          */
 228
 229         strcpy(v->name, "FM");
 230         v->type = V4L2_TUNER_RADIO;
 231         v->rangelow = FREQ_MIN * FREQ_MUL;
 232         v->rangehigh = FREQ_MAX * FREQ_MUL;
 233         v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 234         /* v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO; */
 235         v->audmode = radio->stereo ?
 236                 V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
 237         return 0;
 238 }
 239
 240 /* vidioc_s_tuner - set tuner attributes */
 241 static int vidioc_s_tuner(struct file *file, void *priv,
 242                                 const struct v4l2_tuner *v)
 243 {
 244         struct ma901radio_device *radio = video_drvdata(file);
 245
 246         if (v->index > 0)
 247                 return -EINVAL;
 248
 249         /* mono/stereo selector */
 250         switch (v->audmode) {
 251         case V4L2_TUNER_MODE_MONO:
 252                 return ma901_set_stereo(radio, MA901_WANT_MONO);
 253         default:
 254                 return ma901_set_stereo(radio, MA901_WANT_STEREO);
 255         }
 256 }
 257
 258 /* vidioc_s_frequency - set tuner radio frequency */
 259 static int vidioc_s_frequency(struct file *file, void *priv,
 260                                 const struct v4l2_frequency *f)
 261 {
 262         struct ma901radio_device *radio = video_drvdata(file);
 263
 264         if (f->tuner != 0)
 265                 return -EINVAL;
 266
 267         return ma901radio_set_freq(radio, clamp_t(unsigned, f->frequency,
 268                                 FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
 269 }
 270
 271 /* vidioc_g_frequency - get tuner radio frequency */
 272 static int vidioc_g_frequency(struct file *file, void *priv,
 273                                 struct v4l2_frequency *f)
 274 {
 275         struct ma901radio_device *radio = video_drvdata(file);
 276
 277         if (f->tuner != 0)
 278                 return -EINVAL;
 279         f->frequency = radio->curfreq;
 280
 281         return 0;
 282 }
 283
 284 static int usb_ma901radio_s_ctrl(struct v4l2_ctrl *ctrl)
 285 {
 286         struct ma901radio_device *radio =
 287                 container_of(ctrl->handler, struct ma901radio_device, hdl);
 288
 289         switch (ctrl->id) {
 290         case V4L2_CID_AUDIO_VOLUME:     /* set volume */
 291                 return ma901radio_set_volume(radio, (u16)ctrl->val);
 292         }
 293
 294         return -EINVAL;
 295 }
 296
 297 /* TODO: Should we really need to implement suspend and resume functions?
 298  * Radio has it's own memory and will continue playing if power is present
 299  * on usb port and on resume it will start to play again based on freq, volume
 300  * values in device memory.
 301  */
 302 static int usb_ma901radio_suspend(struct usb_interface *intf, pm_message_t message)
 303 {
 304         return 0;
 305 }
 306
 307 static int usb_ma901radio_resume(struct usb_interface *intf)
 308 {
 309         return 0;
 310 }
 311
 312 static const struct v4l2_ctrl_ops usb_ma901radio_ctrl_ops = {
 313         .s_ctrl = usb_ma901radio_s_ctrl,
 314 };
 315
 316 /* File system interface */
 317 static const struct v4l2_file_operations usb_ma901radio_fops = {
 318         .owner          = THIS_MODULE,
 319         .open           = v4l2_fh_open,
 320         .release        = v4l2_fh_release,
 321         .poll           = v4l2_ctrl_poll,
 322         .unlocked_ioctl = video_ioctl2,
 323 };
 324
 325 static const struct v4l2_ioctl_ops usb_ma901radio_ioctl_ops = {
 326         .vidioc_querycap    = vidioc_querycap,
 327         .vidioc_g_tuner     = vidioc_g_tuner,
 328         .vidioc_s_tuner     = vidioc_s_tuner,
 329         .vidioc_g_frequency = vidioc_g_frequency,
 330         .vidioc_s_frequency = vidioc_s_frequency,
 331         .vidioc_log_status  = v4l2_ctrl_log_status,
 332         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 333         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 334 };
 335
 336 static void usb_ma901radio_release(struct v4l2_device *v4l2_dev)
 337 {
 338         struct ma901radio_device *radio = to_ma901radio_dev(v4l2_dev);
 339
 340         v4l2_ctrl_handler_free(&radio->hdl);
 341         v4l2_device_unregister(&radio->v4l2_dev);
 342         kfree(radio->buffer);
 343         kfree(radio);
 344 }
 345
 346 /* check if the device is present and register with v4l and usb if it is */
 347 static int usb_ma901radio_probe(struct usb_interface *intf,
 348                                 const struct usb_device_id *id)
 349 {
 350         struct ma901radio_device *radio;
 351         int retval = 0;
 352
 353         radio = kzalloc(sizeof(struct ma901radio_device), GFP_KERNEL);
 354         if (!radio) {
 355                 dev_err(&intf->dev, "kzalloc for ma901radio_device failed\n");
 356                 retval = -ENOMEM;
 357                 goto err;
 358         }
 359
 360         radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
 361         if (!radio->buffer) {
 362                 dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
 363                 retval = -ENOMEM;
 364                 goto err_nobuf;
 365         }
 366
 367         retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
 368         if (retval < 0) {
 369                 dev_err(&intf->dev, "couldn't register v4l2_device\n");
 370                 goto err_v4l2;
 371         }
 372
 373         v4l2_ctrl_handler_init(&radio->hdl, 1);
 374
 375         /* TODO:It looks like this radio doesn't have mute/unmute control
 376          * and windows program just emulate it using volume control.
 377          * Let's plan to do the same in this driver.
 378          *
 379          * v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
 380          *                V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 381          */
 382
 383         v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
 384                           V4L2_CID_AUDIO_VOLUME, MA901_VOLUME_MIN,
 385                           MA901_VOLUME_MAX, 1, MA901_VOLUME_MAX);
 386
 387         if (radio->hdl.error) {
 388                 retval = radio->hdl.error;
 389                 dev_err(&intf->dev, "couldn't register control\n");
 390                 goto err_ctrl;
 391         }
 392         mutex_init(&radio->lock);
 393
 394         radio->v4l2_dev.ctrl_handler = &radio->hdl;
 395         radio->v4l2_dev.release = usb_ma901radio_release;
 396         strlcpy(radio->vdev.name, radio->v4l2_dev.name,
 397                 sizeof(radio->vdev.name));
 398         radio->vdev.v4l2_dev = &radio->v4l2_dev;
 399         radio->vdev.fops = &usb_ma901radio_fops;
 400         radio->vdev.ioctl_ops = &usb_ma901radio_ioctl_ops;
 401         radio->vdev.release = video_device_release_empty;
 402         radio->vdev.lock = &radio->lock;
 403         set_bit(V4L2_FL_USE_FH_PRIO, &radio->vdev.flags);
 404
 405         radio->usbdev = interface_to_usbdev(intf);
 406         radio->intf = intf;
 407         usb_set_intfdata(intf, &radio->v4l2_dev);
 408         radio->curfreq = 95.21 * FREQ_MUL;
 409
 410         video_set_drvdata(&radio->vdev, radio);
 411
 412         /* TODO: we can get some statistics (freq, volume) from device
 413          * but it's not implemented yet. After insertion in usb-port radio
 414          * setups frequency and starts playing without any initialization.
 415          * So we don't call usb_ma901radio_init/get_stat() here.
 416          * retval = usb_ma901radio_init(radio);
 417          */
 418
 419         retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
 420                                         radio_nr);
 421         if (retval < 0) {
 422                 dev_err(&intf->dev, "could not register video device\n");
 423                 goto err_vdev;
 424         }
 425
 426         return 0;
 427
 428 err_vdev:
 429         v4l2_ctrl_handler_free(&radio->hdl);
 430 err_ctrl:
 431         v4l2_device_unregister(&radio->v4l2_dev);
 432 err_v4l2:
 433         kfree(radio->buffer);
 434 err_nobuf:
 435         kfree(radio);
 436 err:
 437         return retval;
 438 }
 439
 440 /* USB Device ID List */
 441 static struct usb_device_id usb_ma901radio_device_table[] = {
 442         { USB_DEVICE_AND_INTERFACE_INFO(USB_MA901_VENDOR, USB_MA901_PRODUCT,
 443                                                         USB_CLASS_HID, 0, 0) },
 444         { }                                             /* Terminating entry */
 445 };
 446
 447 MODULE_DEVICE_TABLE(usb, usb_ma901radio_device_table);
 448
 449 /* USB subsystem interface */
 450 static struct usb_driver usb_ma901radio_driver = {
 451         .name                   = MA901_DRIVER_NAME,
 452         .probe                  = usb_ma901radio_probe,
 453         .disconnect             = usb_ma901radio_disconnect,
 454         .suspend                = usb_ma901radio_suspend,
 455         .resume                 = usb_ma901radio_resume,
 456         .reset_resume           = usb_ma901radio_resume,
 457         .id_table               = usb_ma901radio_device_table,
 458 };
 459
 460 module_usb_driver(usb_ma901radio_driver);