1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* A driver for the D-Link DSB-R100 USB radio and Gemtek USB Radio 21. |
3 | * The device plugs into both the USB and an analog audio input, so this thing |
4 | * only deals with initialisation and frequency setting, the |
5 | * audio data has to be handled by a sound driver. |
6 | * |
7 | * Major issue: I can't find out where the device reports the signal |
8 | * strength, and indeed the windows software appearantly just looks |
9 | * at the stereo indicator as well. So, scanning will only find |
10 | * stereo stations. Sad, but I can't help it. |
11 | * |
12 | * Also, the windows program sends oodles of messages over to the |
13 | * device, and I couldn't figure out their meaning. My suspicion |
14 | * is that they don't have any:-) |
15 | * |
16 | * You might find some interesting stuff about this module at |
17 | * http://unimut.fsk.uni-heidelberg.de/unimut/demi/dsbr |
18 | * |
19 | * Fully tested with the Keene USB FM Transmitter and the v4l2-compliance tool. |
20 | * |
21 | * Copyright (c) 2000 Markus Demleitner <msdemlei@cl.uni-heidelberg.de> |
22 | */ |
23 | |
24 | #include <linux/kernel.h> |
25 | #include <linux/module.h> |
26 | #include <linux/init.h> |
27 | #include <linux/slab.h> |
28 | #include <linux/input.h> |
29 | #include <linux/videodev2.h> |
30 | #include <linux/usb.h> |
31 | #include <media/v4l2-device.h> |
32 | #include <media/v4l2-ioctl.h> |
33 | #include <media/v4l2-ctrls.h> |
34 | #include <media/v4l2-event.h> |
35 | |
36 | /* |
37 | * Version Information |
38 | */ |
39 | MODULE_AUTHOR("Markus Demleitner <msdemlei@tucana.harvard.edu>" ); |
40 | MODULE_DESCRIPTION("D-Link DSB-R100 USB FM radio driver" ); |
41 | MODULE_LICENSE("GPL" ); |
42 | MODULE_VERSION("1.1.0" ); |
43 | |
44 | #define DSB100_VENDOR 0x04b4 |
45 | #define DSB100_PRODUCT 0x1002 |
46 | |
47 | /* Commands the device appears to understand */ |
48 | #define DSB100_TUNE 1 |
49 | #define DSB100_ONOFF 2 |
50 | |
51 | #define TB_LEN 16 |
52 | |
53 | /* Frequency limits in MHz -- these are European values. For Japanese |
54 | devices, that would be 76 and 91. */ |
55 | #define FREQ_MIN 87.5 |
56 | #define FREQ_MAX 108.0 |
57 | #define FREQ_MUL 16000 |
58 | |
59 | #define v4l2_dev_to_radio(d) container_of(d, struct dsbr100_device, v4l2_dev) |
60 | |
61 | static int radio_nr = -1; |
62 | module_param(radio_nr, int, 0); |
63 | |
64 | /* Data for one (physical) device */ |
65 | struct dsbr100_device { |
66 | struct usb_device *usbdev; |
67 | struct video_device videodev; |
68 | struct v4l2_device v4l2_dev; |
69 | struct v4l2_ctrl_handler hdl; |
70 | |
71 | u8 *transfer_buffer; |
72 | struct mutex v4l2_lock; |
73 | int curfreq; |
74 | bool stereo; |
75 | bool muted; |
76 | }; |
77 | |
78 | /* Low-level device interface begins here */ |
79 | |
80 | /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */ |
81 | static int dsbr100_setfreq(struct dsbr100_device *radio, unsigned freq) |
82 | { |
83 | unsigned f = (freq / 16 * 80) / 1000 + 856; |
84 | int retval = 0; |
85 | |
86 | if (!radio->muted) { |
87 | retval = usb_control_msg(dev: radio->usbdev, |
88 | usb_rcvctrlpipe(radio->usbdev, 0), |
89 | DSB100_TUNE, |
90 | USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, |
91 | value: (f >> 8) & 0x00ff, index: f & 0xff, |
92 | data: radio->transfer_buffer, size: 8, timeout: 300); |
93 | if (retval >= 0) |
94 | mdelay(1); |
95 | } |
96 | |
97 | if (retval >= 0) { |
98 | radio->curfreq = freq; |
99 | return 0; |
100 | } |
101 | dev_err(&radio->usbdev->dev, |
102 | "%s - usb_control_msg returned %i, request %i\n" , |
103 | __func__, retval, DSB100_TUNE); |
104 | return retval; |
105 | } |
106 | |
107 | /* switch on radio */ |
108 | static int dsbr100_start(struct dsbr100_device *radio) |
109 | { |
110 | int retval = usb_control_msg(dev: radio->usbdev, |
111 | usb_rcvctrlpipe(radio->usbdev, 0), |
112 | DSB100_ONOFF, |
113 | USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, |
114 | value: 0x01, index: 0x00, data: radio->transfer_buffer, size: 8, timeout: 300); |
115 | |
116 | if (retval >= 0) |
117 | return dsbr100_setfreq(radio, freq: radio->curfreq); |
118 | dev_err(&radio->usbdev->dev, |
119 | "%s - usb_control_msg returned %i, request %i\n" , |
120 | __func__, retval, DSB100_ONOFF); |
121 | return retval; |
122 | |
123 | } |
124 | |
125 | /* switch off radio */ |
126 | static int dsbr100_stop(struct dsbr100_device *radio) |
127 | { |
128 | int retval = usb_control_msg(dev: radio->usbdev, |
129 | usb_rcvctrlpipe(radio->usbdev, 0), |
130 | DSB100_ONOFF, |
131 | USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, |
132 | value: 0x00, index: 0x00, data: radio->transfer_buffer, size: 8, timeout: 300); |
133 | |
134 | if (retval >= 0) |
135 | return 0; |
136 | dev_err(&radio->usbdev->dev, |
137 | "%s - usb_control_msg returned %i, request %i\n" , |
138 | __func__, retval, DSB100_ONOFF); |
139 | return retval; |
140 | |
141 | } |
142 | |
143 | /* return the device status. This is, in effect, just whether it |
144 | sees a stereo signal or not. Pity. */ |
145 | static void dsbr100_getstat(struct dsbr100_device *radio) |
146 | { |
147 | int retval = usb_control_msg(dev: radio->usbdev, |
148 | usb_rcvctrlpipe(radio->usbdev, 0), |
149 | USB_REQ_GET_STATUS, |
150 | USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, |
151 | value: 0x00, index: 0x24, data: radio->transfer_buffer, size: 8, timeout: 300); |
152 | |
153 | if (retval < 0) { |
154 | radio->stereo = false; |
155 | dev_err(&radio->usbdev->dev, |
156 | "%s - usb_control_msg returned %i, request %i\n" , |
157 | __func__, retval, USB_REQ_GET_STATUS); |
158 | } else { |
159 | radio->stereo = !(radio->transfer_buffer[0] & 0x01); |
160 | } |
161 | } |
162 | |
163 | static int vidioc_querycap(struct file *file, void *priv, |
164 | struct v4l2_capability *v) |
165 | { |
166 | struct dsbr100_device *radio = video_drvdata(file); |
167 | |
168 | strscpy(v->driver, "dsbr100" , sizeof(v->driver)); |
169 | strscpy(v->card, "D-Link R-100 USB FM Radio" , sizeof(v->card)); |
170 | usb_make_path(dev: radio->usbdev, buf: v->bus_info, size: sizeof(v->bus_info)); |
171 | return 0; |
172 | } |
173 | |
174 | static int vidioc_g_tuner(struct file *file, void *priv, |
175 | struct v4l2_tuner *v) |
176 | { |
177 | struct dsbr100_device *radio = video_drvdata(file); |
178 | |
179 | if (v->index > 0) |
180 | return -EINVAL; |
181 | |
182 | dsbr100_getstat(radio); |
183 | strscpy(v->name, "FM" , sizeof(v->name)); |
184 | v->type = V4L2_TUNER_RADIO; |
185 | v->rangelow = FREQ_MIN * FREQ_MUL; |
186 | v->rangehigh = FREQ_MAX * FREQ_MUL; |
187 | v->rxsubchans = radio->stereo ? V4L2_TUNER_SUB_STEREO : |
188 | V4L2_TUNER_SUB_MONO; |
189 | v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO; |
190 | v->audmode = V4L2_TUNER_MODE_STEREO; |
191 | v->signal = radio->stereo ? 0xffff : 0; /* We can't get the signal strength */ |
192 | return 0; |
193 | } |
194 | |
195 | static int vidioc_s_tuner(struct file *file, void *priv, |
196 | const struct v4l2_tuner *v) |
197 | { |
198 | return v->index ? -EINVAL : 0; |
199 | } |
200 | |
201 | static int vidioc_s_frequency(struct file *file, void *priv, |
202 | const struct v4l2_frequency *f) |
203 | { |
204 | struct dsbr100_device *radio = video_drvdata(file); |
205 | |
206 | if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO) |
207 | return -EINVAL; |
208 | |
209 | return dsbr100_setfreq(radio, clamp_t(unsigned, f->frequency, |
210 | FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL)); |
211 | } |
212 | |
213 | static int vidioc_g_frequency(struct file *file, void *priv, |
214 | struct v4l2_frequency *f) |
215 | { |
216 | struct dsbr100_device *radio = video_drvdata(file); |
217 | |
218 | if (f->tuner) |
219 | return -EINVAL; |
220 | f->type = V4L2_TUNER_RADIO; |
221 | f->frequency = radio->curfreq; |
222 | return 0; |
223 | } |
224 | |
225 | static int usb_dsbr100_s_ctrl(struct v4l2_ctrl *ctrl) |
226 | { |
227 | struct dsbr100_device *radio = |
228 | container_of(ctrl->handler, struct dsbr100_device, hdl); |
229 | |
230 | switch (ctrl->id) { |
231 | case V4L2_CID_AUDIO_MUTE: |
232 | radio->muted = ctrl->val; |
233 | return radio->muted ? dsbr100_stop(radio) : dsbr100_start(radio); |
234 | } |
235 | return -EINVAL; |
236 | } |
237 | |
238 | |
239 | /* USB subsystem interface begins here */ |
240 | |
241 | /* |
242 | * Handle unplugging of the device. |
243 | * We call video_unregister_device in any case. |
244 | * The last function called in this procedure is |
245 | * usb_dsbr100_video_device_release |
246 | */ |
247 | static void usb_dsbr100_disconnect(struct usb_interface *intf) |
248 | { |
249 | struct dsbr100_device *radio = usb_get_intfdata(intf); |
250 | |
251 | mutex_lock(&radio->v4l2_lock); |
252 | /* |
253 | * Disconnect is also called on unload, and in that case we need to |
254 | * mute the device. This call will silently fail if it is called |
255 | * after a physical disconnect. |
256 | */ |
257 | usb_control_msg(dev: radio->usbdev, |
258 | usb_rcvctrlpipe(radio->usbdev, 0), |
259 | DSB100_ONOFF, |
260 | USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, |
261 | value: 0x00, index: 0x00, data: radio->transfer_buffer, size: 8, timeout: 300); |
262 | usb_set_intfdata(intf, NULL); |
263 | video_unregister_device(vdev: &radio->videodev); |
264 | v4l2_device_disconnect(v4l2_dev: &radio->v4l2_dev); |
265 | mutex_unlock(lock: &radio->v4l2_lock); |
266 | v4l2_device_put(v4l2_dev: &radio->v4l2_dev); |
267 | } |
268 | |
269 | |
270 | /* Suspend device - stop device. */ |
271 | static int usb_dsbr100_suspend(struct usb_interface *intf, pm_message_t message) |
272 | { |
273 | struct dsbr100_device *radio = usb_get_intfdata(intf); |
274 | |
275 | mutex_lock(&radio->v4l2_lock); |
276 | if (!radio->muted && dsbr100_stop(radio) < 0) |
277 | dev_warn(&intf->dev, "dsbr100_stop failed\n" ); |
278 | mutex_unlock(lock: &radio->v4l2_lock); |
279 | |
280 | dev_info(&intf->dev, "going into suspend..\n" ); |
281 | return 0; |
282 | } |
283 | |
284 | /* Resume device - start device. */ |
285 | static int usb_dsbr100_resume(struct usb_interface *intf) |
286 | { |
287 | struct dsbr100_device *radio = usb_get_intfdata(intf); |
288 | |
289 | mutex_lock(&radio->v4l2_lock); |
290 | if (!radio->muted && dsbr100_start(radio) < 0) |
291 | dev_warn(&intf->dev, "dsbr100_start failed\n" ); |
292 | mutex_unlock(lock: &radio->v4l2_lock); |
293 | |
294 | dev_info(&intf->dev, "coming out of suspend..\n" ); |
295 | return 0; |
296 | } |
297 | |
298 | /* free data structures */ |
299 | static void usb_dsbr100_release(struct v4l2_device *v4l2_dev) |
300 | { |
301 | struct dsbr100_device *radio = v4l2_dev_to_radio(v4l2_dev); |
302 | |
303 | v4l2_ctrl_handler_free(hdl: &radio->hdl); |
304 | v4l2_device_unregister(v4l2_dev: &radio->v4l2_dev); |
305 | kfree(objp: radio->transfer_buffer); |
306 | kfree(objp: radio); |
307 | } |
308 | |
309 | static const struct v4l2_ctrl_ops usb_dsbr100_ctrl_ops = { |
310 | .s_ctrl = usb_dsbr100_s_ctrl, |
311 | }; |
312 | |
313 | /* File system interface */ |
314 | static const struct v4l2_file_operations usb_dsbr100_fops = { |
315 | .owner = THIS_MODULE, |
316 | .unlocked_ioctl = video_ioctl2, |
317 | .open = v4l2_fh_open, |
318 | .release = v4l2_fh_release, |
319 | .poll = v4l2_ctrl_poll, |
320 | }; |
321 | |
322 | static const struct v4l2_ioctl_ops usb_dsbr100_ioctl_ops = { |
323 | .vidioc_querycap = vidioc_querycap, |
324 | .vidioc_g_tuner = vidioc_g_tuner, |
325 | .vidioc_s_tuner = vidioc_s_tuner, |
326 | .vidioc_g_frequency = vidioc_g_frequency, |
327 | .vidioc_s_frequency = vidioc_s_frequency, |
328 | .vidioc_log_status = v4l2_ctrl_log_status, |
329 | .vidioc_subscribe_event = v4l2_ctrl_subscribe_event, |
330 | .vidioc_unsubscribe_event = v4l2_event_unsubscribe, |
331 | }; |
332 | |
333 | /* check if the device is present and register with v4l and usb if it is */ |
334 | static int usb_dsbr100_probe(struct usb_interface *intf, |
335 | const struct usb_device_id *id) |
336 | { |
337 | struct dsbr100_device *radio; |
338 | struct v4l2_device *v4l2_dev; |
339 | int retval; |
340 | |
341 | radio = kzalloc(size: sizeof(struct dsbr100_device), GFP_KERNEL); |
342 | |
343 | if (!radio) |
344 | return -ENOMEM; |
345 | |
346 | radio->transfer_buffer = kmalloc(TB_LEN, GFP_KERNEL); |
347 | |
348 | if (!(radio->transfer_buffer)) { |
349 | kfree(objp: radio); |
350 | return -ENOMEM; |
351 | } |
352 | |
353 | v4l2_dev = &radio->v4l2_dev; |
354 | v4l2_dev->release = usb_dsbr100_release; |
355 | |
356 | retval = v4l2_device_register(dev: &intf->dev, v4l2_dev); |
357 | if (retval < 0) { |
358 | v4l2_err(v4l2_dev, "couldn't register v4l2_device\n" ); |
359 | goto err_reg_dev; |
360 | } |
361 | |
362 | v4l2_ctrl_handler_init(&radio->hdl, 1); |
363 | v4l2_ctrl_new_std(hdl: &radio->hdl, ops: &usb_dsbr100_ctrl_ops, |
364 | V4L2_CID_AUDIO_MUTE, min: 0, max: 1, step: 1, def: 1); |
365 | if (radio->hdl.error) { |
366 | retval = radio->hdl.error; |
367 | v4l2_err(v4l2_dev, "couldn't register control\n" ); |
368 | goto err_reg_ctrl; |
369 | } |
370 | mutex_init(&radio->v4l2_lock); |
371 | strscpy(radio->videodev.name, v4l2_dev->name, |
372 | sizeof(radio->videodev.name)); |
373 | radio->videodev.v4l2_dev = v4l2_dev; |
374 | radio->videodev.fops = &usb_dsbr100_fops; |
375 | radio->videodev.ioctl_ops = &usb_dsbr100_ioctl_ops; |
376 | radio->videodev.release = video_device_release_empty; |
377 | radio->videodev.lock = &radio->v4l2_lock; |
378 | radio->videodev.ctrl_handler = &radio->hdl; |
379 | radio->videodev.device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER; |
380 | |
381 | radio->usbdev = interface_to_usbdev(intf); |
382 | radio->curfreq = FREQ_MIN * FREQ_MUL; |
383 | radio->muted = true; |
384 | |
385 | video_set_drvdata(vdev: &radio->videodev, data: radio); |
386 | usb_set_intfdata(intf, data: radio); |
387 | |
388 | retval = video_register_device(vdev: &radio->videodev, type: VFL_TYPE_RADIO, nr: radio_nr); |
389 | if (retval == 0) |
390 | return 0; |
391 | v4l2_err(v4l2_dev, "couldn't register video device\n" ); |
392 | |
393 | err_reg_ctrl: |
394 | v4l2_ctrl_handler_free(hdl: &radio->hdl); |
395 | v4l2_device_unregister(v4l2_dev); |
396 | err_reg_dev: |
397 | kfree(objp: radio->transfer_buffer); |
398 | kfree(objp: radio); |
399 | return retval; |
400 | } |
401 | |
402 | static const struct usb_device_id usb_dsbr100_device_table[] = { |
403 | { USB_DEVICE(DSB100_VENDOR, DSB100_PRODUCT) }, |
404 | { } /* Terminating entry */ |
405 | }; |
406 | |
407 | MODULE_DEVICE_TABLE(usb, usb_dsbr100_device_table); |
408 | |
409 | /* USB subsystem interface */ |
410 | static struct usb_driver usb_dsbr100_driver = { |
411 | .name = "dsbr100" , |
412 | .probe = usb_dsbr100_probe, |
413 | .disconnect = usb_dsbr100_disconnect, |
414 | .id_table = usb_dsbr100_device_table, |
415 | .suspend = usb_dsbr100_suspend, |
416 | .resume = usb_dsbr100_resume, |
417 | .reset_resume = usb_dsbr100_resume, |
418 | }; |
419 | |
420 | module_usb_driver(usb_dsbr100_driver); |
421 | |