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
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/init.h>
  22 #include <linux/slab.h>
  23 #include <linux/input.h>
  24 #include <linux/videodev2.h>
  25 #include <media/v4l2-device.h>
  26 #include <media/v4l2-ioctl.h>
  27 #include <media/v4l2-ctrls.h>
  28 #include <media/v4l2-event.h>
  29 #include <linux/usb.h>
  30 #include <linux/mutex.h>
  31
  32 #define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
  33 #define DRIVER_DESC "Masterkit MA901 USB FM radio driver"
  34 #define DRIVER_VERSION "0.0.1"
  35
  36 MODULE_AUTHOR(DRIVER_AUTHOR);
  37 MODULE_DESCRIPTION(DRIVER_DESC);
  38 MODULE_LICENSE("GPL");
  39 MODULE_VERSION(DRIVER_VERSION);
  40
  41 #define USB_MA901_VENDOR  0x16c0
  42 #define USB_MA901_PRODUCT 0x05df
  43
  44 /* dev_warn macro with driver name */
  45 #define MA901_DRIVER_NAME "radio-ma901"
  46 #define ma901radio_dev_warn(dev, fmt, arg...)                           \
  47                 dev_warn(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
  48
  49 #define ma901radio_dev_err(dev, fmt, arg...) \
  50                 dev_err(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
  51
  52 /* Probably USB_TIMEOUT should be modified in module parameter */
  53 #define BUFFER_LENGTH 8
  54 #define USB_TIMEOUT 500
  55
  56 #define FREQ_MIN  87.5
  57 #define FREQ_MAX 108.0
  58 #define FREQ_MUL 16000
  59
  60 #define MA901_VOLUME_MAX 16
  61 #define MA901_VOLUME_MIN 0
  62
  63 /* Commands that device should understand
  64  * List isn't full and will be updated with implementation of new functions
  65  */
  66 #define MA901_RADIO_SET_FREQ            0x03
  67 #define MA901_RADIO_SET_VOLUME          0x04
  68 #define MA901_RADIO_SET_MONO_STEREO     0x05
  69
  70 /* Comfortable defines for ma901radio_set_stereo */
  71 #define MA901_WANT_STEREO               0x50
  72 #define MA901_WANT_MONO                 0xd0
  73
  74 /* module parameter */
  75 static int radio_nr = -1;
  76 module_param(radio_nr, int, 0);
  77 MODULE_PARM_DESC(radio_nr, "Radio file number");
  78
  79 /* Data for one (physical) device */
  80 struct ma901radio_device {
  81         /* reference to USB and video device */
  82         struct usb_device *usbdev;
  83         struct usb_interface *intf;
  84         struct video_device vdev;
  85         struct v4l2_device v4l2_dev;
  86         struct v4l2_ctrl_handler hdl;
  87
  88         u8 *buffer;
  89         struct mutex lock;      /* buffer locking */
  90         int curfreq;
  91         u16 volume;
  92         int stereo;
  93         bool muted;
  94 };
  95
  96 static inline struct ma901radio_device *to_ma901radio_dev(struct v4l2_device *v4l2_dev)
  97 {
  98         return container_of(v4l2_dev, struct ma901radio_device, v4l2_dev);
  99 }
 100
 101 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
 102 static int ma901radio_set_freq(struct ma901radio_device *radio, int freq)
 103 {
 104         unsigned int freq_send = 0x300 + (freq >> 5) / 25;
 105         int retval;
 106
 107         radio->buffer[0] = 0x0a;
 108         radio->buffer[1] = MA901_RADIO_SET_FREQ;
 109         radio->buffer[2] = ((freq_send >> 8) & 0xff) + 0x80;
 110         radio->buffer[3] = freq_send & 0xff;
 111         radio->buffer[4] = 0x00;
 112         radio->buffer[5] = 0x00;
 113         radio->buffer[6] = 0x00;
 114         radio->buffer[7] = 0x00;
 115
 116         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 117                                 9, 0x21, 0x0300, 0,
 118                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 119         if (retval < 0)
 120                 return retval;
 121
 122         radio->curfreq = freq;
 123         return 0;
 124 }
 125
 126 static int ma901radio_set_volume(struct ma901radio_device *radio, u16 vol_to_set)
 127 {
 128         int retval;
 129
 130         radio->buffer[0] = 0x0a;
 131         radio->buffer[1] = MA901_RADIO_SET_VOLUME;
 132         radio->buffer[2] = 0xc2;
 133         radio->buffer[3] = vol_to_set + 0x20;
 134         radio->buffer[4] = 0x00;
 135         radio->buffer[5] = 0x00;
 136         radio->buffer[6] = 0x00;
 137         radio->buffer[7] = 0x00;
 138
 139         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 140                                 9, 0x21, 0x0300, 0,
 141                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 142         if (retval < 0)
 143                 return retval;
 144
 145         radio->volume = vol_to_set;
 146         return retval;
 147 }
 148
 149 static int ma901_set_stereo(struct ma901radio_device *radio, u8 stereo)
 150 {
 151         int retval;
 152
 153         radio->buffer[0] = 0x0a;
 154         radio->buffer[1] = MA901_RADIO_SET_MONO_STEREO;
 155         radio->buffer[2] = stereo;
 156         radio->buffer[3] = 0x00;
 157         radio->buffer[4] = 0x00;
 158         radio->buffer[5] = 0x00;
 159         radio->buffer[6] = 0x00;
 160         radio->buffer[7] = 0x00;
 161
 162         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 163                                 9, 0x21, 0x0300, 0,
 164                                 radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
 165
 166         if (retval < 0)
 167                 return retval;
 168
 169         if (stereo == MA901_WANT_STEREO)
 170                 radio->stereo = V4L2_TUNER_MODE_STEREO;
 171         else
 172                 radio->stereo = V4L2_TUNER_MODE_MONO;
 173
 174         return retval;
 175 }
 176
 177 /* Handle unplugging the device.
 178  * We call video_unregister_device in any case.
 179  * The last function called in this procedure is
 180  * usb_ma901radio_device_release.
 181  */
 182 static void usb_ma901radio_disconnect(struct usb_interface *intf)
 183 {
 184         struct ma901radio_device *radio = to_ma901radio_dev(usb_get_intfdata(intf));
 185
 186         mutex_lock(&radio->lock);
 187         video_unregister_device(&radio->vdev);
 188         usb_set_intfdata(intf, NULL);
 189         v4l2_device_disconnect(&radio->v4l2_dev);
 190         mutex_unlock(&radio->lock);
 191         v4l2_device_put(&radio->v4l2_dev);
 192 }
 193
 194 /* vidioc_querycap - query device capabilities */
 195 static int vidioc_querycap(struct file *file, void *priv,
 196                                         struct v4l2_capability *v)
 197 {
 198         struct ma901radio_device *radio = video_drvdata(file);
 199
 200         strlcpy(v->driver, "radio-ma901", sizeof(v->driver));
 201         strlcpy(v->card, "Masterkit MA901 USB FM Radio", sizeof(v->card));
 202         usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
 203         v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
 204         v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
 205         return 0;
 206 }
 207
 208 /* vidioc_g_tuner - get tuner attributes */
 209 static int vidioc_g_tuner(struct file *file, void *priv,
 210                                 struct v4l2_tuner *v)
 211 {
 212         struct ma901radio_device *radio = video_drvdata(file);
 213
 214         if (v->index > 0)
 215                 return -EINVAL;
 216
 217         v->signal = 0;
 218
 219         /* TODO: the same words like in _probe() goes here.
 220          * When receiving of stats will be implemented then we can call
 221          * ma901radio_get_stat().
 222          * retval = ma901radio_get_stat(radio, &is_stereo, &v->signal);
 223          */
 224
 225         strcpy(v->name, "FM");
 226         v->type = V4L2_TUNER_RADIO;
 227         v->rangelow = FREQ_MIN * FREQ_MUL;
 228         v->rangehigh = FREQ_MAX * FREQ_MUL;
 229         v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
 230         /* v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO; */
 231         v->audmode = radio->stereo ?
 232                 V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
 233         return 0;
 234 }
 235
 236 /* vidioc_s_tuner - set tuner attributes */
 237 static int vidioc_s_tuner(struct file *file, void *priv,
 238                                 const struct v4l2_tuner *v)
 239 {
 240         struct ma901radio_device *radio = video_drvdata(file);
 241
 242         if (v->index > 0)
 243                 return -EINVAL;
 244
 245         /* mono/stereo selector */
 246         switch (v->audmode) {
 247         case V4L2_TUNER_MODE_MONO:
 248                 return ma901_set_stereo(radio, MA901_WANT_MONO);
 249         default:
 250                 return ma901_set_stereo(radio, MA901_WANT_STEREO);
 251         }
 252 }
 253
 254 /* vidioc_s_frequency - set tuner radio frequency */
 255 static int vidioc_s_frequency(struct file *file, void *priv,
 256                                 const struct v4l2_frequency *f)
 257 {
 258         struct ma901radio_device *radio = video_drvdata(file);
 259
 260         if (f->tuner != 0)
 261                 return -EINVAL;
 262
 263         return ma901radio_set_freq(radio, clamp_t(unsigned, f->frequency,
 264                                 FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
 265 }
 266
 267 /* vidioc_g_frequency - get tuner radio frequency */
 268 static int vidioc_g_frequency(struct file *file, void *priv,
 269                                 struct v4l2_frequency *f)
 270 {
 271         struct ma901radio_device *radio = video_drvdata(file);
 272
 273         if (f->tuner != 0)
 274                 return -EINVAL;
 275         f->frequency = radio->curfreq;
 276
 277         return 0;
 278 }
 279
 280 static int usb_ma901radio_s_ctrl(struct v4l2_ctrl *ctrl)
 281 {
 282         struct ma901radio_device *radio =
 283                 container_of(ctrl->handler, struct ma901radio_device, hdl);
 284
 285         switch (ctrl->id) {
 286         case V4L2_CID_AUDIO_VOLUME:     /* set volume */
 287                 return ma901radio_set_volume(radio, (u16)ctrl->val);
 288         }
 289
 290         return -EINVAL;
 291 }
 292
 293 /* TODO: Should we really need to implement suspend and resume functions?
 294  * Radio has it's own memory and will continue playing if power is present
 295  * on usb port and on resume it will start to play again based on freq, volume
 296  * values in device memory.
 297  */
 298 static int usb_ma901radio_suspend(struct usb_interface *intf, pm_message_t message)
 299 {
 300         return 0;
 301 }
 302
 303 static int usb_ma901radio_resume(struct usb_interface *intf)
 304 {
 305         return 0;
 306 }
 307
 308 static const struct v4l2_ctrl_ops usb_ma901radio_ctrl_ops = {
 309         .s_ctrl = usb_ma901radio_s_ctrl,
 310 };
 311
 312 /* File system interface */
 313 static const struct v4l2_file_operations usb_ma901radio_fops = {
 314         .owner          = THIS_MODULE,
 315         .open           = v4l2_fh_open,
 316         .release        = v4l2_fh_release,
 317         .poll           = v4l2_ctrl_poll,
 318         .unlocked_ioctl = video_ioctl2,
 319 };
 320
 321 static const struct v4l2_ioctl_ops usb_ma901radio_ioctl_ops = {
 322         .vidioc_querycap    = vidioc_querycap,
 323         .vidioc_g_tuner     = vidioc_g_tuner,
 324         .vidioc_s_tuner     = vidioc_s_tuner,
 325         .vidioc_g_frequency = vidioc_g_frequency,
 326         .vidioc_s_frequency = vidioc_s_frequency,
 327         .vidioc_log_status  = v4l2_ctrl_log_status,
 328         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 329         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 330 };
 331
 332 static void usb_ma901radio_release(struct v4l2_device *v4l2_dev)
 333 {
 334         struct ma901radio_device *radio = to_ma901radio_dev(v4l2_dev);
 335
 336         v4l2_ctrl_handler_free(&radio->hdl);
 337         v4l2_device_unregister(&radio->v4l2_dev);
 338         kfree(radio->buffer);
 339         kfree(radio);
 340 }
 341
 342 /* check if the device is present and register with v4l and usb if it is */
 343 static int usb_ma901radio_probe(struct usb_interface *intf,
 344                                 const struct usb_device_id *id)
 345 {
 346         struct usb_device *dev = interface_to_usbdev(intf);
 347         struct ma901radio_device *radio;
 348         int retval = 0;
 349
 350         /* Masterkit MA901 usb radio has the same USB ID as many others
 351          * Atmel V-USB devices. Let's make additional checks to be sure
 352          * that this is our device.
 353          */
 354
 355         if (dev->product && dev->manufacturer &&
 356                 (strncmp(dev->product, "MA901", 5) != 0
 357                 || strncmp(dev->manufacturer, "www.masterkit.ru", 16) != 0))
 358                 return -ENODEV;
 359
 360         radio = kzalloc(sizeof(struct ma901radio_device), GFP_KERNEL);
 361         if (!radio) {
 362                 dev_err(&intf->dev, "kzalloc for ma901radio_device failed\n");
 363                 retval = -ENOMEM;
 364                 goto err;
 365         }
 366
 367         radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
 368         if (!radio->buffer) {
 369                 dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
 370                 retval = -ENOMEM;
 371                 goto err_nobuf;
 372         }
 373
 374         retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
 375         if (retval < 0) {
 376                 dev_err(&intf->dev, "couldn't register v4l2_device\n");
 377                 goto err_v4l2;
 378         }
 379
 380         v4l2_ctrl_handler_init(&radio->hdl, 1);
 381
 382         /* TODO:It looks like this radio doesn't have mute/unmute control
 383          * and windows program just emulate it using volume control.
 384          * Let's plan to do the same in this driver.
 385          *
 386          * v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
 387          *                V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 388          */
 389
 390         v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
 391                           V4L2_CID_AUDIO_VOLUME, MA901_VOLUME_MIN,
 392                           MA901_VOLUME_MAX, 1, MA901_VOLUME_MAX);
 393
 394         if (radio->hdl.error) {
 395                 retval = radio->hdl.error;
 396                 dev_err(&intf->dev, "couldn't register control\n");
 397                 goto err_ctrl;
 398         }
 399         mutex_init(&radio->lock);
 400
 401         radio->v4l2_dev.ctrl_handler = &radio->hdl;
 402         radio->v4l2_dev.release = usb_ma901radio_release;
 403         strlcpy(radio->vdev.name, radio->v4l2_dev.name,
 404                 sizeof(radio->vdev.name));
 405         radio->vdev.v4l2_dev = &radio->v4l2_dev;
 406         radio->vdev.fops = &usb_ma901radio_fops;
 407         radio->vdev.ioctl_ops = &usb_ma901radio_ioctl_ops;
 408         radio->vdev.release = video_device_release_empty;
 409         radio->vdev.lock = &radio->lock;
 410
 411         radio->usbdev = interface_to_usbdev(intf);
 412         radio->intf = intf;
 413         usb_set_intfdata(intf, &radio->v4l2_dev);
 414         radio->curfreq = 95.21 * FREQ_MUL;
 415
 416         video_set_drvdata(&radio->vdev, radio);
 417
 418         /* TODO: we can get some statistics (freq, volume) from device
 419          * but it's not implemented yet. After insertion in usb-port radio
 420          * setups frequency and starts playing without any initialization.
 421          * So we don't call usb_ma901radio_init/get_stat() here.
 422          * retval = usb_ma901radio_init(radio);
 423          */
 424
 425         retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
 426                                         radio_nr);
 427         if (retval < 0) {
 428                 dev_err(&intf->dev, "could not register video device\n");
 429                 goto err_vdev;
 430         }
 431
 432         return 0;
 433
 434 err_vdev:
 435         v4l2_ctrl_handler_free(&radio->hdl);
 436 err_ctrl:
 437         v4l2_device_unregister(&radio->v4l2_dev);
 438 err_v4l2:
 439         kfree(radio->buffer);
 440 err_nobuf:
 441         kfree(radio);
 442 err:
 443         return retval;
 444 }
 445
 446 /* USB Device ID List */
 447 static struct usb_device_id usb_ma901radio_device_table[] = {
 448         { USB_DEVICE_AND_INTERFACE_INFO(USB_MA901_VENDOR, USB_MA901_PRODUCT,
 449                                                         USB_CLASS_HID, 0, 0) },
 450         { }                                             /* Terminating entry */
 451 };
 452
 453 MODULE_DEVICE_TABLE(usb, usb_ma901radio_device_table);
 454
 455 /* USB subsystem interface */
 456 static struct usb_driver usb_ma901radio_driver = {
 457         .name                   = MA901_DRIVER_NAME,
 458         .probe                  = usb_ma901radio_probe,
 459         .disconnect             = usb_ma901radio_disconnect,
 460         .suspend                = usb_ma901radio_suspend,
 461         .resume                 = usb_ma901radio_resume,
 462         .reset_resume           = usb_ma901radio_resume,
 463         .id_table               = usb_ma901radio_device_table,
 464 };
 465
 466 module_usb_driver(usb_ma901radio_driver);