drivers/media/radio/radio-ma901.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Driver for the MasterKit MA901 USB FM radio. This device plugs
   4  * into the USB port and an analog audio input or headphones, so this thing
   5  * only deals with initialization, frequency setting, volume.
   6  *
   7  * Copyright (c) 2012 Alexey Klimov <klimov.linux@gmail.com>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/slab.h>
  14 #include <linux/input.h>
  15 #include <linux/videodev2.h>
  16 #include <media/v4l2-device.h>
  17 #include <media/v4l2-ioctl.h>
  18 #include <media/v4l2-ctrls.h>
  19 #include <media/v4l2-event.h>
  20 #include <linux/usb.h>
  21 #include <linux/mutex.h>
  22
  23 #define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
  24 #define DRIVER_DESC "Masterkit MA901 USB FM radio driver"
  25 #define DRIVER_VERSION "0.0.1"
  26
  27 MODULE_AUTHOR(DRIVER_AUTHOR);
  28 MODULE_DESCRIPTION(DRIVER_DESC);
  29 MODULE_LICENSE("GPL");
  30 MODULE_VERSION(DRIVER_VERSION);
  31
  32 #define USB_MA901_VENDOR  0x16c0
  33 #define USB_MA901_PRODUCT 0x05df
  34
  35 /* dev_warn macro with driver name */
  36 #define MA901_DRIVER_NAME "radio-ma901"
  37 #define ma901radio_dev_warn(dev, fmt, arg...)                           \
  38                 dev_warn(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
  39
  40 #define ma901radio_dev_err(dev, fmt, arg...) \
  41                 dev_err(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
  42
  43 /* Probably USB_TIMEOUT should be modified in module parameter */
  44 #define BUFFER_LENGTH 8
  45 #define USB_TIMEOUT 500
  46
  47 #define FREQ_MIN  87.5
  48 #define FREQ_MAX 108.0
  49 #define FREQ_MUL 16000
  50
  51 #define MA901_VOLUME_MAX 16
  52 #define MA901_VOLUME_MIN 0
  53
  54 /* Commands that device should understand
  55  * List isn't full and will be updated with implementation of new functions
  56  */
  57 #define MA901_RADIO_SET_FREQ            0x03
  58 #define MA901_RADIO_SET_VOLUME          0x04
  59 #define MA901_RADIO_SET_MONO_STEREO     0x05
  60
  61 /* Comfortable defines for ma901radio_set_stereo */
  62 #define MA901_WANT_STEREO               0x50
  63 #define MA901_WANT_MONO                 0xd0
  64
  65 /* module parameter */
  66 static int radio_nr = -1;
  67 module_param(radio_nr, int, 0);
  68 MODULE_PARM_DESC(radio_nr, "Radio file number");
  69
  70 /* Data for one (physical) device */
  71 struct ma901radio_device {
  72         /* reference to USB and video device */
  73         struct usb_device *usbdev;
  74         struct usb_interface *intf;
  75         struct video_device vdev;
  76         struct v4l2_device v4l2_dev;
  77         struct v4l2_ctrl_handler hdl;
  78
  79         u8 *buffer;
  80         struct mutex lock;      /* buffer locking */
  81         int curfreq;
  82         u16 volume;
  83         int stereo;
  84         bool muted;
  85 };
  86
  87 static inline struct ma901radio_device *to_ma901radio_dev(struct v4l2_device *v4l2_dev)
  88 {
  89         return container_of(v4l2_dev, struct ma901radio_device, v4l2_dev);
  90 }
  91
  92 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
  93 static int ma901radio_set_freq(struct ma901radio_device *radio, int freq)
  94 {
  95         unsigned int freq_send = 0x300 + (freq >> 5) / 25;
  96         int retval;
  97
  98         radio->buffer[0] = 0x0a;
  99         radio->buffer[1] = MA901_RADIO_SET_FREQ;
 100         radio->buffer[2] = ((freq_send >> 8) & 0xff) + 0x80;
 101         radio->buffer[3] = freq_send & 0xff;
 102         radio->buffer[4] = 0x00;
 103         radio->buffer[5] = 0x00;
 104         radio->buffer[6] = 0x00;
 105         radio->buffer[7] = 0x00;
 106
 107         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 108                                 9, 0x21, 0x0300, 0,
 109                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 110         if (retval < 0)
 111                 return retval;
 112
 113         radio->curfreq = freq;
 114         return 0;
 115 }
 116
 117 static int ma901radio_set_volume(struct ma901radio_device *radio, u16 vol_to_set)
 118 {
 119         int retval;
 120
 121         radio->buffer[0] = 0x0a;
 122         radio->buffer[1] = MA901_RADIO_SET_VOLUME;
 123         radio->buffer[2] = 0xc2;
 124         radio->buffer[3] = vol_to_set + 0x20;
 125         radio->buffer[4] = 0x00;
 126         radio->buffer[5] = 0x00;
 127         radio->buffer[6] = 0x00;
 128         radio->buffer[7] = 0x00;
 129
 130         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 131                                 9, 0x21, 0x0300, 0,
 132                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 133         if (retval < 0)
 134                 return retval;
 135
 136         radio->volume = vol_to_set;
 137         return retval;
 138 }
 139
 140 static int ma901_set_stereo(struct ma901radio_device *radio, u8 stereo)
 141 {
 142         int retval;
 143
 144         radio->buffer[0] = 0x0a;
 145         radio->buffer[1] = MA901_RADIO_SET_MONO_STEREO;
 146         radio->buffer[2] = stereo;
 147         radio->buffer[3] = 0x00;
 148         radio->buffer[4] = 0x00;
 149         radio->buffer[5] = 0x00;
 150         radio->buffer[6] = 0x00;
 151         radio->buffer[7] = 0x00;
 152
 153         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 154                                 9, 0x21, 0x0300, 0,
 155                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 156
 157         if (retval < 0)
 158                 return retval;
 159
 160         if (stereo == MA901_WANT_STEREO)
 161                 radio->stereo = V4L2_TUNER_MODE_STEREO;
 162         else
 163                 radio->stereo = V4L2_TUNER_MODE_MONO;
 164
 165         return retval;
 166 }
 167
 168 /* Handle unplugging the device.
 169  * We call video_unregister_device in any case.
 170  * The last function called in this procedure is
 171  * usb_ma901radio_device_release.
 172  */
 173 static void usb_ma901radio_disconnect(struct usb_interface *intf)
 174 {
 175         struct ma901radio_device *radio = to_ma901radio_dev(usb_get_intfdata(intf));
 176
 177         mutex_lock(&radio->lock);
 178         video_unregister_device(&radio->vdev);
 179         usb_set_intfdata(intf, NULL);
 180         v4l2_device_disconnect(&radio->v4l2_dev);
 181         mutex_unlock(&radio->lock);
 182         v4l2_device_put(&radio->v4l2_dev);
 183 }
 184
 185 /* vidioc_querycap - query device capabilities */
 186 static int vidioc_querycap(struct file *file, void *priv,
 187                                         struct v4l2_capability *v)
 188 {
 189         struct ma901radio_device *radio = video_drvdata(file);
 190
 191         strscpy(v->driver, "radio-ma901", sizeof(v->driver));
 192         strscpy(v->card, "Masterkit MA901 USB FM Radio", sizeof(v->card));
 193         usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
 194         v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
 195         v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 196         return 0;
 197 }
 198
 199 /* vidioc_g_tuner - get tuner attributes */
 200 static int vidioc_g_tuner(struct file *file, void *priv,
 201                                 struct v4l2_tuner *v)
 202 {
 203         struct ma901radio_device *radio = video_drvdata(file);
 204
 205         if (v->index > 0)
 206                 return -EINVAL;
 207
 208         v->signal = 0;
 209
 210         /* TODO: the same words like in _probe() goes here.
 211          * When receiving of stats will be implemented then we can call
 212          * ma901radio_get_stat().
 213          * retval = ma901radio_get_stat(radio, &is_stereo, &v->signal);
 214          */
 215
 216         strscpy(v->name, "FM", sizeof(v->name));
 217         v->type = V4L2_TUNER_RADIO;
 218         v->rangelow = FREQ_MIN * FREQ_MUL;
 219         v->rangehigh = FREQ_MAX * FREQ_MUL;
 220         v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 221         /* v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO; */
 222         v->audmode = radio->stereo ?
 223                 V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
 224         return 0;
 225 }
 226
 227 /* vidioc_s_tuner - set tuner attributes */
 228 static int vidioc_s_tuner(struct file *file, void *priv,
 229                                 const struct v4l2_tuner *v)
 230 {
 231         struct ma901radio_device *radio = video_drvdata(file);
 232
 233         if (v->index > 0)
 234                 return -EINVAL;
 235
 236         /* mono/stereo selector */
 237         switch (v->audmode) {
 238         case V4L2_TUNER_MODE_MONO:
 239                 return ma901_set_stereo(radio, MA901_WANT_MONO);
 240         default:
 241                 return ma901_set_stereo(radio, MA901_WANT_STEREO);
 242         }
 243 }
 244
 245 /* vidioc_s_frequency - set tuner radio frequency */
 246 static int vidioc_s_frequency(struct file *file, void *priv,
 247                                 const struct v4l2_frequency *f)
 248 {
 249         struct ma901radio_device *radio = video_drvdata(file);
 250
 251         if (f->tuner != 0)
 252                 return -EINVAL;
 253
 254         return ma901radio_set_freq(radio, clamp_t(unsigned, f->frequency,
 255                                 FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
 256 }
 257
 258 /* vidioc_g_frequency - get tuner radio frequency */
 259 static int vidioc_g_frequency(struct file *file, void *priv,
 260                                 struct v4l2_frequency *f)
 261 {
 262         struct ma901radio_device *radio = video_drvdata(file);
 263
 264         if (f->tuner != 0)
 265                 return -EINVAL;
 266         f->frequency = radio->curfreq;
 267
 268         return 0;
 269 }
 270
 271 static int usb_ma901radio_s_ctrl(struct v4l2_ctrl *ctrl)
 272 {
 273         struct ma901radio_device *radio =
 274                 container_of(ctrl->handler, struct ma901radio_device, hdl);
 275
 276         switch (ctrl->id) {
 277         case V4L2_CID_AUDIO_VOLUME:     /* set volume */
 278                 return ma901radio_set_volume(radio, (u16)ctrl->val);
 279         }
 280
 281         return -EINVAL;
 282 }
 283
 284 /* TODO: Should we really need to implement suspend and resume functions?
 285  * Radio has it's own memory and will continue playing if power is present
 286  * on usb port and on resume it will start to play again based on freq, volume
 287  * values in device memory.
 288  */
 289 static int usb_ma901radio_suspend(struct usb_interface *intf, pm_message_t message)
 290 {
 291         return 0;
 292 }
 293
 294 static int usb_ma901radio_resume(struct usb_interface *intf)
 295 {
 296         return 0;
 297 }
 298
 299 static const struct v4l2_ctrl_ops usb_ma901radio_ctrl_ops = {
 300         .s_ctrl = usb_ma901radio_s_ctrl,
 301 };
 302
 303 /* File system interface */
 304 static const struct v4l2_file_operations usb_ma901radio_fops = {
 305         .owner          = THIS_MODULE,
 306         .open           = v4l2_fh_open,
 307         .release        = v4l2_fh_release,
 308         .poll           = v4l2_ctrl_poll,
 309         .unlocked_ioctl = video_ioctl2,
 310 };
 311
 312 static const struct v4l2_ioctl_ops usb_ma901radio_ioctl_ops = {
 313         .vidioc_querycap    = vidioc_querycap,
 314         .vidioc_g_tuner     = vidioc_g_tuner,
 315         .vidioc_s_tuner     = vidioc_s_tuner,
 316         .vidioc_g_frequency = vidioc_g_frequency,
 317         .vidioc_s_frequency = vidioc_s_frequency,
 318         .vidioc_log_status  = v4l2_ctrl_log_status,
 319         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 320         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 321 };
 322
 323 static void usb_ma901radio_release(struct v4l2_device *v4l2_dev)
 324 {
 325         struct ma901radio_device *radio = to_ma901radio_dev(v4l2_dev);
 326
 327         v4l2_ctrl_handler_free(&radio->hdl);
 328         v4l2_device_unregister(&radio->v4l2_dev);
 329         kfree(radio->buffer);
 330         kfree(radio);
 331 }
 332
 333 /* check if the device is present and register with v4l and usb if it is */
 334 static int usb_ma901radio_probe(struct usb_interface *intf,
 335                                 const struct usb_device_id *id)
 336 {
 337         struct usb_device *dev = interface_to_usbdev(intf);
 338         struct ma901radio_device *radio;
 339         int retval = 0;
 340
 341         /* Masterkit MA901 usb radio has the same USB ID as many others
 342          * Atmel V-USB devices. Let's make additional checks to be sure
 343          * that this is our device.
 344          */
 345
 346         if (dev->product && dev->manufacturer &&
 347                 (strncmp(dev->product, "MA901", 5) != 0
 348                 || strncmp(dev->manufacturer, "www.masterkit.ru", 16) != 0))
 349                 return -ENODEV;
 350
 351         radio = kzalloc(sizeof(struct ma901radio_device), GFP_KERNEL);
 352         if (!radio) {
 353                 dev_err(&intf->dev, "kzalloc for ma901radio_device failed\n");
 354                 retval = -ENOMEM;
 355                 goto err;
 356         }
 357
 358         radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
 359         if (!radio->buffer) {
 360                 dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
 361                 retval = -ENOMEM;
 362                 goto err_nobuf;
 363         }
 364
 365         retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
 366         if (retval < 0) {
 367                 dev_err(&intf->dev, "couldn't register v4l2_device\n");
 368                 goto err_v4l2;
 369         }
 370
 371         v4l2_ctrl_handler_init(&radio->hdl, 1);
 372
 373         /* TODO:It looks like this radio doesn't have mute/unmute control
 374          * and windows program just emulate it using volume control.
 375          * Let's plan to do the same in this driver.
 376          *
 377          * v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
 378          *                V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 379          */
 380
 381         v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
 382                           V4L2_CID_AUDIO_VOLUME, MA901_VOLUME_MIN,
 383                           MA901_VOLUME_MAX, 1, MA901_VOLUME_MAX);
 384
 385         if (radio->hdl.error) {
 386                 retval = radio->hdl.error;
 387                 dev_err(&intf->dev, "couldn't register control\n");
 388                 goto err_ctrl;
 389         }
 390         mutex_init(&radio->lock);
 391
 392         radio->v4l2_dev.ctrl_handler = &radio->hdl;
 393         radio->v4l2_dev.release = usb_ma901radio_release;
 394         strscpy(radio->vdev.name, radio->v4l2_dev.name,
 395                 sizeof(radio->vdev.name));
 396         radio->vdev.v4l2_dev = &radio->v4l2_dev;
 397         radio->vdev.fops = &usb_ma901radio_fops;
 398         radio->vdev.ioctl_ops = &usb_ma901radio_ioctl_ops;
 399         radio->vdev.release = video_device_release_empty;
 400         radio->vdev.lock = &radio->lock;
 401
 402         radio->usbdev = interface_to_usbdev(intf);
 403         radio->intf = intf;
 404         usb_set_intfdata(intf, &radio->v4l2_dev);
 405         radio->curfreq = 95.21 * FREQ_MUL;
 406
 407         video_set_drvdata(&radio->vdev, radio);
 408
 409         /* TODO: we can get some statistics (freq, volume) from device
 410          * but it's not implemented yet. After insertion in usb-port radio
 411          * setups frequency and starts playing without any initialization.
 412          * So we don't call usb_ma901radio_init/get_stat() here.
 413          * retval = usb_ma901radio_init(radio);
 414          */
 415
 416         retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
 417                                         radio_nr);
 418         if (retval < 0) {
 419                 dev_err(&intf->dev, "could not register video device\n");
 420                 goto err_vdev;
 421         }
 422
 423         return 0;
 424
 425 err_vdev:
 426         v4l2_ctrl_handler_free(&radio->hdl);
 427 err_ctrl:
 428         v4l2_device_unregister(&radio->v4l2_dev);
 429 err_v4l2:
 430         kfree(radio->buffer);
 431 err_nobuf:
 432         kfree(radio);
 433 err:
 434         return retval;
 435 }
 436
 437 /* USB Device ID List */
 438 static const struct usb_device_id usb_ma901radio_device_table[] = {
 439         { USB_DEVICE_AND_INTERFACE_INFO(USB_MA901_VENDOR, USB_MA901_PRODUCT,
 440                                                         USB_CLASS_HID, 0, 0) },
 441         { }                                             /* Terminating entry */
 442 };
 443
 444 MODULE_DEVICE_TABLE(usb, usb_ma901radio_device_table);
 445
 446 /* USB subsystem interface */
 447 static struct usb_driver usb_ma901radio_driver = {
 448         .name                   = MA901_DRIVER_NAME,
 449         .probe                  = usb_ma901radio_probe,
 450         .disconnect             = usb_ma901radio_disconnect,
 451         .suspend                = usb_ma901radio_suspend,
 452         .resume                 = usb_ma901radio_resume,
 453         .reset_resume           = usb_ma901radio_resume,
 454         .id_table               = usb_ma901radio_device_table,
 455 };
 456
 457 module_usb_driver(usb_ma901radio_driver);