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
to_ma901radio_dev(struct v4l2_device * v4l2_dev)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 */
ma901radio_set_freq(struct ma901radio_device * radio,int freq)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
ma901radio_set_volume(struct ma901radio_device * radio,u16 vol_to_set)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
ma901_set_stereo(struct ma901radio_device * radio,u8 stereo)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 */
usb_ma901radio_disconnect(struct usb_interface * intf)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 */
vidioc_querycap(struct file * file,void * priv,struct v4l2_capability * v)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 return 0;
195 }
196
197 /* vidioc_g_tuner - get tuner attributes */
vidioc_g_tuner(struct file * file,void * priv,struct v4l2_tuner * v)198 static int vidioc_g_tuner(struct file *file, void *priv,
199 struct v4l2_tuner *v)
200 {
201 struct ma901radio_device *radio = video_drvdata(file);
202
203 if (v->index > 0)
204 return -EINVAL;
205
206 v->signal = 0;
207
208 /* TODO: the same words like in _probe() goes here.
209 * When receiving of stats will be implemented then we can call
210 * ma901radio_get_stat().
211 * retval = ma901radio_get_stat(radio, &is_stereo, &v->signal);
212 */
213
214 strscpy(v->name, "FM", sizeof(v->name));
215 v->type = V4L2_TUNER_RADIO;
216 v->rangelow = FREQ_MIN * FREQ_MUL;
217 v->rangehigh = FREQ_MAX * FREQ_MUL;
218 v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
219 /* v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO; */
220 v->audmode = radio->stereo ?
221 V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
222 return 0;
223 }
224
225 /* vidioc_s_tuner - set tuner attributes */
vidioc_s_tuner(struct file * file,void * priv,const struct v4l2_tuner * v)226 static int vidioc_s_tuner(struct file *file, void *priv,
227 const struct v4l2_tuner *v)
228 {
229 struct ma901radio_device *radio = video_drvdata(file);
230
231 if (v->index > 0)
232 return -EINVAL;
233
234 /* mono/stereo selector */
235 switch (v->audmode) {
236 case V4L2_TUNER_MODE_MONO:
237 return ma901_set_stereo(radio, MA901_WANT_MONO);
238 default:
239 return ma901_set_stereo(radio, MA901_WANT_STEREO);
240 }
241 }
242
243 /* vidioc_s_frequency - set tuner radio frequency */
vidioc_s_frequency(struct file * file,void * priv,const struct v4l2_frequency * f)244 static int vidioc_s_frequency(struct file *file, void *priv,
245 const struct v4l2_frequency *f)
246 {
247 struct ma901radio_device *radio = video_drvdata(file);
248
249 if (f->tuner != 0)
250 return -EINVAL;
251
252 return ma901radio_set_freq(radio, clamp_t(unsigned, f->frequency,
253 FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
254 }
255
256 /* vidioc_g_frequency - get tuner radio frequency */
vidioc_g_frequency(struct file * file,void * priv,struct v4l2_frequency * f)257 static int vidioc_g_frequency(struct file *file, void *priv,
258 struct v4l2_frequency *f)
259 {
260 struct ma901radio_device *radio = video_drvdata(file);
261
262 if (f->tuner != 0)
263 return -EINVAL;
264 f->frequency = radio->curfreq;
265
266 return 0;
267 }
268
usb_ma901radio_s_ctrl(struct v4l2_ctrl * ctrl)269 static int usb_ma901radio_s_ctrl(struct v4l2_ctrl *ctrl)
270 {
271 struct ma901radio_device *radio =
272 container_of(ctrl->handler, struct ma901radio_device, hdl);
273
274 switch (ctrl->id) {
275 case V4L2_CID_AUDIO_VOLUME: /* set volume */
276 return ma901radio_set_volume(radio, (u16)ctrl->val);
277 }
278
279 return -EINVAL;
280 }
281
282 /* TODO: Should we really need to implement suspend and resume functions?
283 * Radio has it's own memory and will continue playing if power is present
284 * on usb port and on resume it will start to play again based on freq, volume
285 * values in device memory.
286 */
usb_ma901radio_suspend(struct usb_interface * intf,pm_message_t message)287 static int usb_ma901radio_suspend(struct usb_interface *intf, pm_message_t message)
288 {
289 return 0;
290 }
291
usb_ma901radio_resume(struct usb_interface * intf)292 static int usb_ma901radio_resume(struct usb_interface *intf)
293 {
294 return 0;
295 }
296
297 static const struct v4l2_ctrl_ops usb_ma901radio_ctrl_ops = {
298 .s_ctrl = usb_ma901radio_s_ctrl,
299 };
300
301 /* File system interface */
302 static const struct v4l2_file_operations usb_ma901radio_fops = {
303 .owner = THIS_MODULE,
304 .open = v4l2_fh_open,
305 .release = v4l2_fh_release,
306 .poll = v4l2_ctrl_poll,
307 .unlocked_ioctl = video_ioctl2,
308 };
309
310 static const struct v4l2_ioctl_ops usb_ma901radio_ioctl_ops = {
311 .vidioc_querycap = vidioc_querycap,
312 .vidioc_g_tuner = vidioc_g_tuner,
313 .vidioc_s_tuner = vidioc_s_tuner,
314 .vidioc_g_frequency = vidioc_g_frequency,
315 .vidioc_s_frequency = vidioc_s_frequency,
316 .vidioc_log_status = v4l2_ctrl_log_status,
317 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
318 .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
319 };
320
usb_ma901radio_release(struct v4l2_device * v4l2_dev)321 static void usb_ma901radio_release(struct v4l2_device *v4l2_dev)
322 {
323 struct ma901radio_device *radio = to_ma901radio_dev(v4l2_dev);
324
325 v4l2_ctrl_handler_free(&radio->hdl);
326 v4l2_device_unregister(&radio->v4l2_dev);
327 kfree(radio->buffer);
328 kfree(radio);
329 }
330
331 /* check if the device is present and register with v4l and usb if it is */
usb_ma901radio_probe(struct usb_interface * intf,const struct usb_device_id * id)332 static int usb_ma901radio_probe(struct usb_interface *intf,
333 const struct usb_device_id *id)
334 {
335 struct usb_device *dev = interface_to_usbdev(intf);
336 struct ma901radio_device *radio;
337 int retval = 0;
338
339 /* Masterkit MA901 usb radio has the same USB ID as many others
340 * Atmel V-USB devices. Let's make additional checks to be sure
341 * that this is our device.
342 */
343
344 if (dev->product && dev->manufacturer &&
345 (strncmp(dev->product, "MA901", 5) != 0
346 || strncmp(dev->manufacturer, "www.masterkit.ru", 16) != 0))
347 return -ENODEV;
348
349 radio = kzalloc(sizeof(struct ma901radio_device), GFP_KERNEL);
350 if (!radio) {
351 dev_err(&intf->dev, "kzalloc for ma901radio_device failed\n");
352 retval = -ENOMEM;
353 goto err;
354 }
355
356 radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
357 if (!radio->buffer) {
358 dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
359 retval = -ENOMEM;
360 goto err_nobuf;
361 }
362
363 retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
364 if (retval < 0) {
365 dev_err(&intf->dev, "couldn't register v4l2_device\n");
366 goto err_v4l2;
367 }
368
369 v4l2_ctrl_handler_init(&radio->hdl, 1);
370
371 /* TODO:It looks like this radio doesn't have mute/unmute control
372 * and windows program just emulate it using volume control.
373 * Let's plan to do the same in this driver.
374 *
375 * v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
376 * V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
377 */
378
379 v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
380 V4L2_CID_AUDIO_VOLUME, MA901_VOLUME_MIN,
381 MA901_VOLUME_MAX, 1, MA901_VOLUME_MAX);
382
383 if (radio->hdl.error) {
384 retval = radio->hdl.error;
385 dev_err(&intf->dev, "couldn't register control\n");
386 goto err_ctrl;
387 }
388 mutex_init(&radio->lock);
389
390 radio->v4l2_dev.ctrl_handler = &radio->hdl;
391 radio->v4l2_dev.release = usb_ma901radio_release;
392 strscpy(radio->vdev.name, radio->v4l2_dev.name,
393 sizeof(radio->vdev.name));
394 radio->vdev.v4l2_dev = &radio->v4l2_dev;
395 radio->vdev.fops = &usb_ma901radio_fops;
396 radio->vdev.ioctl_ops = &usb_ma901radio_ioctl_ops;
397 radio->vdev.release = video_device_release_empty;
398 radio->vdev.lock = &radio->lock;
399 radio->vdev.device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
400
401 radio->usbdev = interface_to_usbdev(intf);
402 radio->intf = intf;
403 usb_set_intfdata(intf, &radio->v4l2_dev);
404 radio->curfreq = 95.21 * FREQ_MUL;
405
406 video_set_drvdata(&radio->vdev, radio);
407
408 /* TODO: we can get some statistics (freq, volume) from device
409 * but it's not implemented yet. After insertion in usb-port radio
410 * setups frequency and starts playing without any initialization.
411 * So we don't call usb_ma901radio_init/get_stat() here.
412 * retval = usb_ma901radio_init(radio);
413 */
414
415 retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
416 radio_nr);
417 if (retval < 0) {
418 dev_err(&intf->dev, "could not register video device\n");
419 goto err_vdev;
420 }
421
422 return 0;
423
424 err_vdev:
425 v4l2_ctrl_handler_free(&radio->hdl);
426 err_ctrl:
427 v4l2_device_unregister(&radio->v4l2_dev);
428 err_v4l2:
429 kfree(radio->buffer);
430 err_nobuf:
431 kfree(radio);
432 err:
433 return retval;
434 }
435
436 /* USB Device ID List */
437 static const struct usb_device_id usb_ma901radio_device_table[] = {
438 { USB_DEVICE_AND_INTERFACE_INFO(USB_MA901_VENDOR, USB_MA901_PRODUCT,
439 USB_CLASS_HID, 0, 0) },
440 { } /* Terminating entry */
441 };
442
443 MODULE_DEVICE_TABLE(usb, usb_ma901radio_device_table);
444
445 /* USB subsystem interface */
446 static struct usb_driver usb_ma901radio_driver = {
447 .name = MA901_DRIVER_NAME,
448 .probe = usb_ma901radio_probe,
449 .disconnect = usb_ma901radio_disconnect,
450 .suspend = usb_ma901radio_suspend,
451 .resume = usb_ma901radio_resume,
452 .reset_resume = usb_ma901radio_resume,
453 .id_table = usb_ma901radio_device_table,
454 };
455
456 module_usb_driver(usb_ma901radio_driver);
457