xref: /openbmc/linux/drivers/media/radio/dsbr100.c (revision 95e9fd10)
1 /* A driver for the D-Link DSB-R100 USB radio and Gemtek USB Radio 21.
2  * The device plugs into both the USB and an analog audio input, so this thing
3  * only deals with initialisation and frequency setting, the
4  * audio data has to be handled by a sound driver.
5  *
6  * Major issue: I can't find out where the device reports the signal
7  * strength, and indeed the windows software appearantly just looks
8  * at the stereo indicator as well.  So, scanning will only find
9  * stereo stations.  Sad, but I can't help it.
10  *
11  * Also, the windows program sends oodles of messages over to the
12  * device, and I couldn't figure out their meaning.  My suspicion
13  * is that they don't have any:-)
14  *
15  * You might find some interesting stuff about this module at
16  * http://unimut.fsk.uni-heidelberg.de/unimut/demi/dsbr
17  *
18  * Fully tested with the Keene USB FM Transmitter and the v4l2-compliance tool.
19  *
20  * Copyright (c) 2000 Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
21  *
22  * This program is free software; you can redistribute it and/or modify
23  * it under the terms of the GNU General Public License as published by
24  * the Free Software Foundation; either version 2 of the License, or
25  * (at your option) any later version.
26  *
27  * This program is distributed in the hope that it will be useful,
28  * but WITHOUT ANY WARRANTY; without even the implied warranty of
29  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
30  * GNU General Public License for more details.
31  *
32  * You should have received a copy of the GNU General Public License
33  * along with this program; if not, write to the Free Software
34  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
35 */
36 
37 #include <linux/kernel.h>
38 #include <linux/module.h>
39 #include <linux/init.h>
40 #include <linux/slab.h>
41 #include <linux/input.h>
42 #include <linux/videodev2.h>
43 #include <linux/usb.h>
44 #include <media/v4l2-device.h>
45 #include <media/v4l2-ioctl.h>
46 #include <media/v4l2-ctrls.h>
47 #include <media/v4l2-event.h>
48 
49 /*
50  * Version Information
51  */
52 MODULE_AUTHOR("Markus Demleitner <msdemlei@tucana.harvard.edu>");
53 MODULE_DESCRIPTION("D-Link DSB-R100 USB FM radio driver");
54 MODULE_LICENSE("GPL");
55 MODULE_VERSION("1.1.0");
56 
57 #define DSB100_VENDOR 0x04b4
58 #define DSB100_PRODUCT 0x1002
59 
60 /* Commands the device appears to understand */
61 #define DSB100_TUNE 1
62 #define DSB100_ONOFF 2
63 
64 #define TB_LEN 16
65 
66 /* Frequency limits in MHz -- these are European values.  For Japanese
67 devices, that would be 76 and 91.  */
68 #define FREQ_MIN  87.5
69 #define FREQ_MAX 108.0
70 #define FREQ_MUL 16000
71 
72 #define v4l2_dev_to_radio(d) container_of(d, struct dsbr100_device, v4l2_dev)
73 
74 static int radio_nr = -1;
75 module_param(radio_nr, int, 0);
76 
77 /* Data for one (physical) device */
78 struct dsbr100_device {
79 	struct usb_device *usbdev;
80 	struct video_device videodev;
81 	struct v4l2_device v4l2_dev;
82 	struct v4l2_ctrl_handler hdl;
83 
84 	u8 *transfer_buffer;
85 	struct mutex v4l2_lock;
86 	int curfreq;
87 	bool stereo;
88 	bool muted;
89 };
90 
91 /* Low-level device interface begins here */
92 
93 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
94 static int dsbr100_setfreq(struct dsbr100_device *radio, unsigned freq)
95 {
96 	unsigned f = (freq / 16 * 80) / 1000 + 856;
97 	int retval = 0;
98 
99 	if (!radio->muted) {
100 		retval = usb_control_msg(radio->usbdev,
101 				usb_rcvctrlpipe(radio->usbdev, 0),
102 				DSB100_TUNE,
103 				USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
104 				(f >> 8) & 0x00ff, f & 0xff,
105 				radio->transfer_buffer, 8, 300);
106 		if (retval >= 0)
107 			mdelay(1);
108 	}
109 
110 	if (retval >= 0) {
111 		radio->curfreq = freq;
112 		return 0;
113 	}
114 	dev_err(&radio->usbdev->dev,
115 		"%s - usb_control_msg returned %i, request %i\n",
116 			__func__, retval, DSB100_TUNE);
117 	return retval;
118 }
119 
120 /* switch on radio */
121 static int dsbr100_start(struct dsbr100_device *radio)
122 {
123 	int retval = usb_control_msg(radio->usbdev,
124 		usb_rcvctrlpipe(radio->usbdev, 0),
125 		DSB100_ONOFF,
126 		USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
127 		0x01, 0x00, radio->transfer_buffer, 8, 300);
128 
129 	if (retval >= 0)
130 		return dsbr100_setfreq(radio, radio->curfreq);
131 	dev_err(&radio->usbdev->dev,
132 		"%s - usb_control_msg returned %i, request %i\n",
133 			__func__, retval, DSB100_ONOFF);
134 	return retval;
135 
136 }
137 
138 /* switch off radio */
139 static int dsbr100_stop(struct dsbr100_device *radio)
140 {
141 	int retval = usb_control_msg(radio->usbdev,
142 		usb_rcvctrlpipe(radio->usbdev, 0),
143 		DSB100_ONOFF,
144 		USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
145 		0x00, 0x00, radio->transfer_buffer, 8, 300);
146 
147 	if (retval >= 0)
148 		return 0;
149 	dev_err(&radio->usbdev->dev,
150 		"%s - usb_control_msg returned %i, request %i\n",
151 			__func__, retval, DSB100_ONOFF);
152 	return retval;
153 
154 }
155 
156 /* return the device status.  This is, in effect, just whether it
157 sees a stereo signal or not.  Pity. */
158 static void dsbr100_getstat(struct dsbr100_device *radio)
159 {
160 	int retval = usb_control_msg(radio->usbdev,
161 		usb_rcvctrlpipe(radio->usbdev, 0),
162 		USB_REQ_GET_STATUS,
163 		USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
164 		0x00, 0x24, radio->transfer_buffer, 8, 300);
165 
166 	if (retval < 0) {
167 		radio->stereo = false;
168 		dev_err(&radio->usbdev->dev,
169 			"%s - usb_control_msg returned %i, request %i\n",
170 				__func__, retval, USB_REQ_GET_STATUS);
171 	} else {
172 		radio->stereo = !(radio->transfer_buffer[0] & 0x01);
173 	}
174 }
175 
176 static int vidioc_querycap(struct file *file, void *priv,
177 					struct v4l2_capability *v)
178 {
179 	struct dsbr100_device *radio = video_drvdata(file);
180 
181 	strlcpy(v->driver, "dsbr100", sizeof(v->driver));
182 	strlcpy(v->card, "D-Link R-100 USB FM Radio", sizeof(v->card));
183 	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
184 	v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
185 	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
186 	return 0;
187 }
188 
189 static int vidioc_g_tuner(struct file *file, void *priv,
190 				struct v4l2_tuner *v)
191 {
192 	struct dsbr100_device *radio = video_drvdata(file);
193 
194 	if (v->index > 0)
195 		return -EINVAL;
196 
197 	dsbr100_getstat(radio);
198 	strcpy(v->name, "FM");
199 	v->type = V4L2_TUNER_RADIO;
200 	v->rangelow = FREQ_MIN * FREQ_MUL;
201 	v->rangehigh = FREQ_MAX * FREQ_MUL;
202 	v->rxsubchans = radio->stereo ? V4L2_TUNER_SUB_STEREO :
203 		V4L2_TUNER_SUB_MONO;
204 	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
205 	v->audmode = V4L2_TUNER_MODE_STEREO;
206 	v->signal = radio->stereo ? 0xffff : 0;     /* We can't get the signal strength */
207 	return 0;
208 }
209 
210 static int vidioc_s_tuner(struct file *file, void *priv,
211 				struct v4l2_tuner *v)
212 {
213 	return v->index ? -EINVAL : 0;
214 }
215 
216 static int vidioc_s_frequency(struct file *file, void *priv,
217 				struct v4l2_frequency *f)
218 {
219 	struct dsbr100_device *radio = video_drvdata(file);
220 
221 	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
222 		return -EINVAL;
223 
224 	return dsbr100_setfreq(radio, clamp_t(unsigned, f->frequency,
225 			FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
226 }
227 
228 static int vidioc_g_frequency(struct file *file, void *priv,
229 				struct v4l2_frequency *f)
230 {
231 	struct dsbr100_device *radio = video_drvdata(file);
232 
233 	if (f->tuner)
234 		return -EINVAL;
235 	f->type = V4L2_TUNER_RADIO;
236 	f->frequency = radio->curfreq;
237 	return 0;
238 }
239 
240 static int usb_dsbr100_s_ctrl(struct v4l2_ctrl *ctrl)
241 {
242 	struct dsbr100_device *radio =
243 		container_of(ctrl->handler, struct dsbr100_device, hdl);
244 
245 	switch (ctrl->id) {
246 	case V4L2_CID_AUDIO_MUTE:
247 		radio->muted = ctrl->val;
248 		return radio->muted ? dsbr100_stop(radio) : dsbr100_start(radio);
249 	}
250 	return -EINVAL;
251 }
252 
253 
254 /* USB subsystem interface begins here */
255 
256 /*
257  * Handle unplugging of the device.
258  * We call video_unregister_device in any case.
259  * The last function called in this procedure is
260  * usb_dsbr100_video_device_release
261  */
262 static void usb_dsbr100_disconnect(struct usb_interface *intf)
263 {
264 	struct dsbr100_device *radio = usb_get_intfdata(intf);
265 
266 	mutex_lock(&radio->v4l2_lock);
267 	/*
268 	 * Disconnect is also called on unload, and in that case we need to
269 	 * mute the device. This call will silently fail if it is called
270 	 * after a physical disconnect.
271 	 */
272 	usb_control_msg(radio->usbdev,
273 		usb_rcvctrlpipe(radio->usbdev, 0),
274 		DSB100_ONOFF,
275 		USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
276 		0x00, 0x00, radio->transfer_buffer, 8, 300);
277 	usb_set_intfdata(intf, NULL);
278 	video_unregister_device(&radio->videodev);
279 	v4l2_device_disconnect(&radio->v4l2_dev);
280 	mutex_unlock(&radio->v4l2_lock);
281 	v4l2_device_put(&radio->v4l2_dev);
282 }
283 
284 
285 /* Suspend device - stop device. */
286 static int usb_dsbr100_suspend(struct usb_interface *intf, pm_message_t message)
287 {
288 	struct dsbr100_device *radio = usb_get_intfdata(intf);
289 
290 	mutex_lock(&radio->v4l2_lock);
291 	if (!radio->muted && dsbr100_stop(radio) < 0)
292 		dev_warn(&intf->dev, "dsbr100_stop failed\n");
293 	mutex_unlock(&radio->v4l2_lock);
294 
295 	dev_info(&intf->dev, "going into suspend..\n");
296 	return 0;
297 }
298 
299 /* Resume device - start device. */
300 static int usb_dsbr100_resume(struct usb_interface *intf)
301 {
302 	struct dsbr100_device *radio = usb_get_intfdata(intf);
303 
304 	mutex_lock(&radio->v4l2_lock);
305 	if (!radio->muted && dsbr100_start(radio) < 0)
306 		dev_warn(&intf->dev, "dsbr100_start failed\n");
307 	mutex_unlock(&radio->v4l2_lock);
308 
309 	dev_info(&intf->dev, "coming out of suspend..\n");
310 	return 0;
311 }
312 
313 /* free data structures */
314 static void usb_dsbr100_release(struct v4l2_device *v4l2_dev)
315 {
316 	struct dsbr100_device *radio = v4l2_dev_to_radio(v4l2_dev);
317 
318 	v4l2_ctrl_handler_free(&radio->hdl);
319 	v4l2_device_unregister(&radio->v4l2_dev);
320 	kfree(radio->transfer_buffer);
321 	kfree(radio);
322 }
323 
324 static const struct v4l2_ctrl_ops usb_dsbr100_ctrl_ops = {
325 	.s_ctrl = usb_dsbr100_s_ctrl,
326 };
327 
328 /* File system interface */
329 static const struct v4l2_file_operations usb_dsbr100_fops = {
330 	.owner		= THIS_MODULE,
331 	.unlocked_ioctl	= video_ioctl2,
332 	.open           = v4l2_fh_open,
333 	.release        = v4l2_fh_release,
334 	.poll		= v4l2_ctrl_poll,
335 };
336 
337 static const struct v4l2_ioctl_ops usb_dsbr100_ioctl_ops = {
338 	.vidioc_querycap    = vidioc_querycap,
339 	.vidioc_g_tuner     = vidioc_g_tuner,
340 	.vidioc_s_tuner     = vidioc_s_tuner,
341 	.vidioc_g_frequency = vidioc_g_frequency,
342 	.vidioc_s_frequency = vidioc_s_frequency,
343 	.vidioc_log_status  = v4l2_ctrl_log_status,
344 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
345 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
346 };
347 
348 /* check if the device is present and register with v4l and usb if it is */
349 static int usb_dsbr100_probe(struct usb_interface *intf,
350 				const struct usb_device_id *id)
351 {
352 	struct dsbr100_device *radio;
353 	struct v4l2_device *v4l2_dev;
354 	int retval;
355 
356 	radio = kzalloc(sizeof(struct dsbr100_device), GFP_KERNEL);
357 
358 	if (!radio)
359 		return -ENOMEM;
360 
361 	radio->transfer_buffer = kmalloc(TB_LEN, GFP_KERNEL);
362 
363 	if (!(radio->transfer_buffer)) {
364 		kfree(radio);
365 		return -ENOMEM;
366 	}
367 
368 	v4l2_dev = &radio->v4l2_dev;
369 	v4l2_dev->release = usb_dsbr100_release;
370 
371 	retval = v4l2_device_register(&intf->dev, v4l2_dev);
372 	if (retval < 0) {
373 		v4l2_err(v4l2_dev, "couldn't register v4l2_device\n");
374 		goto err_reg_dev;
375 	}
376 
377 	v4l2_ctrl_handler_init(&radio->hdl, 1);
378 	v4l2_ctrl_new_std(&radio->hdl, &usb_dsbr100_ctrl_ops,
379 			  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
380 	if (radio->hdl.error) {
381 		retval = radio->hdl.error;
382 		v4l2_err(v4l2_dev, "couldn't register control\n");
383 		goto err_reg_ctrl;
384 	}
385 	mutex_init(&radio->v4l2_lock);
386 	strlcpy(radio->videodev.name, v4l2_dev->name, sizeof(radio->videodev.name));
387 	radio->videodev.v4l2_dev = v4l2_dev;
388 	radio->videodev.fops = &usb_dsbr100_fops;
389 	radio->videodev.ioctl_ops = &usb_dsbr100_ioctl_ops;
390 	radio->videodev.release = video_device_release_empty;
391 	radio->videodev.lock = &radio->v4l2_lock;
392 	radio->videodev.ctrl_handler = &radio->hdl;
393 	set_bit(V4L2_FL_USE_FH_PRIO, &radio->videodev.flags);
394 
395 	radio->usbdev = interface_to_usbdev(intf);
396 	radio->curfreq = FREQ_MIN * FREQ_MUL;
397 	radio->muted = true;
398 
399 	video_set_drvdata(&radio->videodev, radio);
400 	usb_set_intfdata(intf, radio);
401 
402 	retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO, radio_nr);
403 	if (retval == 0)
404 		return 0;
405 	v4l2_err(v4l2_dev, "couldn't register video device\n");
406 
407 err_reg_ctrl:
408 	v4l2_ctrl_handler_free(&radio->hdl);
409 	v4l2_device_unregister(v4l2_dev);
410 err_reg_dev:
411 	kfree(radio->transfer_buffer);
412 	kfree(radio);
413 	return retval;
414 }
415 
416 static struct usb_device_id usb_dsbr100_device_table[] = {
417 	{ USB_DEVICE(DSB100_VENDOR, DSB100_PRODUCT) },
418 	{ }						/* Terminating entry */
419 };
420 
421 MODULE_DEVICE_TABLE(usb, usb_dsbr100_device_table);
422 
423 /* USB subsystem interface */
424 static struct usb_driver usb_dsbr100_driver = {
425 	.name			= "dsbr100",
426 	.probe			= usb_dsbr100_probe,
427 	.disconnect		= usb_dsbr100_disconnect,
428 	.id_table		= usb_dsbr100_device_table,
429 	.suspend		= usb_dsbr100_suspend,
430 	.resume			= usb_dsbr100_resume,
431 	.reset_resume		= usb_dsbr100_resume,
432 };
433 
434 module_usb_driver(usb_dsbr100_driver);
435