1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A driver for the AverMedia MR 800 USB FM radio. This device plugs
4 * into both the USB and an analog audio input, so this thing
5 * only deals with initialization and frequency setting, the
6 * audio data has to be handled by a sound driver.
7 *
8 * Copyright (c) 2008 Alexey Klimov <klimov.linux@gmail.com>
9 */
10
11/*
12 * Big thanks to authors and contributors of dsbr100.c and radio-si470x.c
13 *
14 * When work was looked pretty good, i discover this:
15 * http://av-usbradio.sourceforge.net/index.php
16 * http://sourceforge.net/projects/av-usbradio/
17 * Latest release of theirs project was in 2005.
18 * Probably, this driver could be improved through using their
19 * achievements (specifications given).
20 * Also, Faidon Liambotis <paravoid@debian.org> wrote nice driver for this radio
21 * in 2007. He allowed to use his driver to improve current mr800 radio driver.
22 * http://www.spinics.net/lists/linux-usb-devel/msg10109.html
23 *
24 * Version 0.01:	First working version.
25 *			It's required to blacklist AverMedia USB Radio
26 *			in usbhid/hid-quirks.c
27 * Version 0.10:	A lot of cleanups and fixes: unpluging the device,
28 *			few mutex locks were added, codinstyle issues, etc.
29 *			Added stereo support. Thanks to
30 *			Douglas Schilling Landgraf <dougsland@gmail.com> and
31 *			David Ellingsworth <david@identd.dyndns.org>
32 *			for discussion, help and support.
33 * Version 0.11:	Converted to v4l2_device.
34 *
35 * Many things to do:
36 *	- Correct power management of device (suspend & resume)
37 *	- Add code for scanning and smooth tuning
38 *	- Add code for sensitivity value
39 *	- Correct mistakes
40 *	- In Japan another FREQ_MIN and FREQ_MAX
41 */
42
43/* kernel includes */
44#include <linux/kernel.h>
45#include <linux/module.h>
46#include <linux/init.h>
47#include <linux/slab.h>
48#include <linux/input.h>
49#include <linux/videodev2.h>
50#include <media/v4l2-device.h>
51#include <media/v4l2-ioctl.h>
52#include <media/v4l2-ctrls.h>
53#include <media/v4l2-event.h>
54#include <linux/usb.h>
55#include <linux/mutex.h>
56
57/* driver and module definitions */
58#define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
59#define DRIVER_DESC "AverMedia MR 800 USB FM radio driver"
60#define DRIVER_VERSION "0.1.2"
61
62MODULE_AUTHOR(DRIVER_AUTHOR);
63MODULE_DESCRIPTION(DRIVER_DESC);
64MODULE_LICENSE("GPL");
65MODULE_VERSION(DRIVER_VERSION);
66
67#define USB_AMRADIO_VENDOR 0x07ca
68#define USB_AMRADIO_PRODUCT 0xb800
69
70/* dev_warn macro with driver name */
71#define MR800_DRIVER_NAME "radio-mr800"
72#define amradio_dev_warn(dev, fmt, arg...)				\
73		dev_warn(dev, MR800_DRIVER_NAME " - " fmt, ##arg)
74
75#define amradio_dev_err(dev, fmt, arg...) \
76		dev_err(dev, MR800_DRIVER_NAME " - " fmt, ##arg)
77
78/* Probably USB_TIMEOUT should be modified in module parameter */
79#define BUFFER_LENGTH 8
80#define USB_TIMEOUT 500
81
82/* Frequency limits in MHz -- these are European values.  For Japanese
83devices, that would be 76 and 91.  */
84#define FREQ_MIN  87.5
85#define FREQ_MAX 108.0
86#define FREQ_MUL 16000
87
88/*
89 * Commands that device should understand
90 * List isn't full and will be updated with implementation of new functions
91 */
92#define AMRADIO_SET_FREQ	0xa4
93#define AMRADIO_GET_READY_FLAG	0xa5
94#define AMRADIO_GET_SIGNAL	0xa7
95#define AMRADIO_GET_FREQ	0xa8
96#define AMRADIO_SET_SEARCH_UP	0xa9
97#define AMRADIO_SET_SEARCH_DOWN	0xaa
98#define AMRADIO_SET_MUTE	0xab
99#define AMRADIO_SET_RIGHT_MUTE	0xac
100#define AMRADIO_SET_LEFT_MUTE	0xad
101#define AMRADIO_SET_MONO	0xae
102#define AMRADIO_SET_SEARCH_LVL	0xb0
103#define AMRADIO_STOP_SEARCH	0xb1
104
105/* Comfortable defines for amradio_set_stereo */
106#define WANT_STEREO		0x00
107#define WANT_MONO		0x01
108
109/* module parameter */
110static int radio_nr = -1;
111module_param(radio_nr, int, 0);
112MODULE_PARM_DESC(radio_nr, "Radio Nr");
113
114/* Data for one (physical) device */
115struct amradio_device {
116	/* reference to USB and video device */
117	struct usb_device *usbdev;
118	struct usb_interface *intf;
119	struct video_device vdev;
120	struct v4l2_device v4l2_dev;
121	struct v4l2_ctrl_handler hdl;
122
123	u8 *buffer;
124	struct mutex lock;	/* buffer locking */
125	int curfreq;
126	int stereo;
127	int muted;
128};
129
130static inline struct amradio_device *to_amradio_dev(struct v4l2_device *v4l2_dev)
131{
132	return container_of(v4l2_dev, struct amradio_device, v4l2_dev);
133}
134
135static int amradio_send_cmd(struct amradio_device *radio, u8 cmd, u8 arg,
136		u8 *extra, u8 extralen, bool reply)
137{
138	int retval;
139	int size;
140
141	radio->buffer[0] = 0x00;
142	radio->buffer[1] = 0x55;
143	radio->buffer[2] = 0xaa;
144	radio->buffer[3] = extralen;
145	radio->buffer[4] = cmd;
146	radio->buffer[5] = arg;
147	radio->buffer[6] = 0x00;
148	radio->buffer[7] = extra || reply ? 8 : 0;
149
150	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
151		radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
152
153	if (retval < 0 || size != BUFFER_LENGTH) {
154		if (video_is_registered(&radio->vdev))
155			amradio_dev_warn(&radio->vdev.dev,
156					"cmd %02x failed\n", cmd);
157		return retval ? retval : -EIO;
158	}
159	if (!extra && !reply)
160		return 0;
161
162	if (extra) {
163		memcpy(radio->buffer, extra, extralen);
164		memset(radio->buffer + extralen, 0, 8 - extralen);
165		retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
166			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
167	} else {
168		memset(radio->buffer, 0, 8);
169		retval = usb_bulk_msg(radio->usbdev, usb_rcvbulkpipe(radio->usbdev, 0x81),
170			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
171	}
172	if (retval == 0 && size == BUFFER_LENGTH)
173		return 0;
174	if (video_is_registered(&radio->vdev) && cmd != AMRADIO_GET_READY_FLAG)
175		amradio_dev_warn(&radio->vdev.dev, "follow-up to cmd %02x failed\n", cmd);
176	return retval ? retval : -EIO;
177}
178
179/* switch on/off the radio. Send 8 bytes to device */
180static int amradio_set_mute(struct amradio_device *radio, bool mute)
181{
182	int ret = amradio_send_cmd(radio,
183			AMRADIO_SET_MUTE, mute, NULL, 0, false);
184
185	if (!ret)
186		radio->muted = mute;
187	return ret;
188}
189
190/* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
191static int amradio_set_freq(struct amradio_device *radio, int freq)
192{
193	unsigned short freq_send;
194	u8 buf[3];
195	int retval;
196
197	/* we need to be sure that frequency isn't out of range */
198	freq = clamp_t(unsigned, freq, FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL);
199	freq_send = 0x10 + (freq >> 3) / 25;
200
201	/* frequency is calculated from freq_send and placed in first 2 bytes */
202	buf[0] = (freq_send >> 8) & 0xff;
203	buf[1] = freq_send & 0xff;
204	buf[2] = 0x01;
205
206	retval = amradio_send_cmd(radio, AMRADIO_SET_FREQ, 0, buf, 3, false);
207	if (retval)
208		return retval;
209	radio->curfreq = freq;
210	msleep(40);
211	return 0;
212}
213
214static int amradio_set_stereo(struct amradio_device *radio, bool stereo)
215{
216	int ret = amradio_send_cmd(radio,
217			AMRADIO_SET_MONO, !stereo, NULL, 0, false);
218
219	if (!ret)
220		radio->stereo = stereo;
221	return ret;
222}
223
224static int amradio_get_stat(struct amradio_device *radio, bool *is_stereo, u32 *signal)
225{
226	int ret = amradio_send_cmd(radio,
227			AMRADIO_GET_SIGNAL, 0, NULL, 0, true);
228
229	if (ret)
230		return ret;
231	*is_stereo = radio->buffer[2] >> 7;
232	*signal = (radio->buffer[3] & 0xf0) << 8;
233	return 0;
234}
235
236/* Handle unplugging the device.
237 * We call video_unregister_device in any case.
238 * The last function called in this procedure is
239 * usb_amradio_device_release.
240 */
241static void usb_amradio_disconnect(struct usb_interface *intf)
242{
243	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
244
245	mutex_lock(&radio->lock);
246	video_unregister_device(&radio->vdev);
247	amradio_set_mute(radio, true);
248	usb_set_intfdata(intf, NULL);
249	v4l2_device_disconnect(&radio->v4l2_dev);
250	mutex_unlock(&radio->lock);
251	v4l2_device_put(&radio->v4l2_dev);
252}
253
254/* vidioc_querycap - query device capabilities */
255static int vidioc_querycap(struct file *file, void *priv,
256					struct v4l2_capability *v)
257{
258	struct amradio_device *radio = video_drvdata(file);
259
260	strscpy(v->driver, "radio-mr800", sizeof(v->driver));
261	strscpy(v->card, "AverMedia MR 800 USB FM Radio", sizeof(v->card));
262	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
263	return 0;
264}
265
266/* vidioc_g_tuner - get tuner attributes */
267static int vidioc_g_tuner(struct file *file, void *priv,
268				struct v4l2_tuner *v)
269{
270	struct amradio_device *radio = video_drvdata(file);
271	bool is_stereo = false;
272	int retval;
273
274	if (v->index > 0)
275		return -EINVAL;
276
277	v->signal = 0;
278	retval = amradio_get_stat(radio, &is_stereo, &v->signal);
279	if (retval)
280		return retval;
281
282	strscpy(v->name, "FM", sizeof(v->name));
283	v->type = V4L2_TUNER_RADIO;
284	v->rangelow = FREQ_MIN * FREQ_MUL;
285	v->rangehigh = FREQ_MAX * FREQ_MUL;
286	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
287		V4L2_TUNER_CAP_HWSEEK_WRAP;
288	v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
289	v->audmode = radio->stereo ?
290		V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
291	return 0;
292}
293
294/* vidioc_s_tuner - set tuner attributes */
295static int vidioc_s_tuner(struct file *file, void *priv,
296				const struct v4l2_tuner *v)
297{
298	struct amradio_device *radio = video_drvdata(file);
299
300	if (v->index > 0)
301		return -EINVAL;
302
303	/* mono/stereo selector */
304	switch (v->audmode) {
305	case V4L2_TUNER_MODE_MONO:
306		return amradio_set_stereo(radio, WANT_MONO);
307	default:
308		return amradio_set_stereo(radio, WANT_STEREO);
309	}
310}
311
312/* vidioc_s_frequency - set tuner radio frequency */
313static int vidioc_s_frequency(struct file *file, void *priv,
314				const struct v4l2_frequency *f)
315{
316	struct amradio_device *radio = video_drvdata(file);
317
318	if (f->tuner != 0)
319		return -EINVAL;
320	return amradio_set_freq(radio, f->frequency);
321}
322
323/* vidioc_g_frequency - get tuner radio frequency */
324static int vidioc_g_frequency(struct file *file, void *priv,
325				struct v4l2_frequency *f)
326{
327	struct amradio_device *radio = video_drvdata(file);
328
329	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
330		return -EINVAL;
331	f->type = V4L2_TUNER_RADIO;
332	f->frequency = radio->curfreq;
333
334	return 0;
335}
336
337static int vidioc_s_hw_freq_seek(struct file *file, void *priv,
338		const struct v4l2_hw_freq_seek *seek)
339{
340	static u8 buf[8] = {
341		0x3d, 0x32, 0x0f, 0x08, 0x3d, 0x32, 0x0f, 0x08
342	};
343	struct amradio_device *radio = video_drvdata(file);
344	unsigned long timeout;
345	int retval;
346
347	if (seek->tuner != 0 || !seek->wrap_around)
348		return -EINVAL;
349
350	if (file->f_flags & O_NONBLOCK)
351		return -EWOULDBLOCK;
352
353	retval = amradio_send_cmd(radio,
354			AMRADIO_SET_SEARCH_LVL, 0, buf, 8, false);
355	if (retval)
356		return retval;
357	amradio_set_freq(radio, radio->curfreq);
358	retval = amradio_send_cmd(radio,
359		seek->seek_upward ? AMRADIO_SET_SEARCH_UP : AMRADIO_SET_SEARCH_DOWN,
360		0, NULL, 0, false);
361	if (retval)
362		return retval;
363	timeout = jiffies + msecs_to_jiffies(30000);
364	for (;;) {
365		if (time_after(jiffies, timeout)) {
366			retval = -ENODATA;
367			break;
368		}
369		if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
370			retval = -ERESTARTSYS;
371			break;
372		}
373		retval = amradio_send_cmd(radio, AMRADIO_GET_READY_FLAG,
374				0, NULL, 0, true);
375		if (retval)
376			continue;
377		amradio_send_cmd(radio, AMRADIO_GET_FREQ, 0, NULL, 0, true);
378		if (radio->buffer[1] || radio->buffer[2]) {
379			/* To check: sometimes radio->curfreq is set to out of range value */
380			radio->curfreq = (radio->buffer[1] << 8) | radio->buffer[2];
381			radio->curfreq = (radio->curfreq - 0x10) * 200;
382			amradio_send_cmd(radio, AMRADIO_STOP_SEARCH,
383					0, NULL, 0, false);
384			amradio_set_freq(radio, radio->curfreq);
385			retval = 0;
386			break;
387		}
388	}
389	amradio_send_cmd(radio, AMRADIO_STOP_SEARCH, 0, NULL, 0, false);
390	amradio_set_freq(radio, radio->curfreq);
391	return retval;
392}
393
394static int usb_amradio_s_ctrl(struct v4l2_ctrl *ctrl)
395{
396	struct amradio_device *radio =
397		container_of(ctrl->handler, struct amradio_device, hdl);
398
399	switch (ctrl->id) {
400	case V4L2_CID_AUDIO_MUTE:
401		return amradio_set_mute(radio, ctrl->val);
402	}
403
404	return -EINVAL;
405}
406
407static int usb_amradio_init(struct amradio_device *radio)
408{
409	int retval;
410
411	retval = amradio_set_mute(radio, true);
412	if (retval)
413		goto out_err;
414	retval = amradio_set_stereo(radio, true);
415	if (retval)
416		goto out_err;
417	retval = amradio_set_freq(radio, radio->curfreq);
418	if (retval)
419		goto out_err;
420	return 0;
421
422out_err:
423	amradio_dev_err(&radio->vdev.dev, "initialization failed\n");
424	return retval;
425}
426
427/* Suspend device - stop device. Need to be checked and fixed */
428static int usb_amradio_suspend(struct usb_interface *intf, pm_message_t message)
429{
430	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
431
432	mutex_lock(&radio->lock);
433	if (!radio->muted) {
434		amradio_set_mute(radio, true);
435		radio->muted = false;
436	}
437	mutex_unlock(&radio->lock);
438
439	dev_info(&intf->dev, "going into suspend..\n");
440	return 0;
441}
442
443/* Resume device - start device. Need to be checked and fixed */
444static int usb_amradio_resume(struct usb_interface *intf)
445{
446	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
447
448	mutex_lock(&radio->lock);
449	amradio_set_stereo(radio, radio->stereo);
450	amradio_set_freq(radio, radio->curfreq);
451
452	if (!radio->muted)
453		amradio_set_mute(radio, false);
454
455	mutex_unlock(&radio->lock);
456
457	dev_info(&intf->dev, "coming out of suspend..\n");
458	return 0;
459}
460
461static const struct v4l2_ctrl_ops usb_amradio_ctrl_ops = {
462	.s_ctrl = usb_amradio_s_ctrl,
463};
464
465/* File system interface */
466static const struct v4l2_file_operations usb_amradio_fops = {
467	.owner		= THIS_MODULE,
468	.open		= v4l2_fh_open,
469	.release	= v4l2_fh_release,
470	.poll		= v4l2_ctrl_poll,
471	.unlocked_ioctl	= video_ioctl2,
472};
473
474static const struct v4l2_ioctl_ops usb_amradio_ioctl_ops = {
475	.vidioc_querycap    = vidioc_querycap,
476	.vidioc_g_tuner     = vidioc_g_tuner,
477	.vidioc_s_tuner     = vidioc_s_tuner,
478	.vidioc_g_frequency = vidioc_g_frequency,
479	.vidioc_s_frequency = vidioc_s_frequency,
480	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
481	.vidioc_log_status  = v4l2_ctrl_log_status,
482	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
483	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
484};
485
486static void usb_amradio_release(struct v4l2_device *v4l2_dev)
487{
488	struct amradio_device *radio = to_amradio_dev(v4l2_dev);
489
490	/* free rest memory */
491	v4l2_ctrl_handler_free(&radio->hdl);
492	v4l2_device_unregister(&radio->v4l2_dev);
493	kfree(radio->buffer);
494	kfree(radio);
495}
496
497/* check if the device is present and register with v4l and usb if it is */
498static int usb_amradio_probe(struct usb_interface *intf,
499				const struct usb_device_id *id)
500{
501	struct amradio_device *radio;
502	int retval;
503
504	radio = kzalloc(sizeof(struct amradio_device), GFP_KERNEL);
505
506	if (!radio) {
507		dev_err(&intf->dev, "kmalloc for amradio_device failed\n");
508		retval = -ENOMEM;
509		goto err;
510	}
511
512	radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
513
514	if (!radio->buffer) {
515		dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
516		retval = -ENOMEM;
517		goto err_nobuf;
518	}
519
520	retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
521	if (retval < 0) {
522		dev_err(&intf->dev, "couldn't register v4l2_device\n");
523		goto err_v4l2;
524	}
525
526	v4l2_ctrl_handler_init(&radio->hdl, 1);
527	v4l2_ctrl_new_std(&radio->hdl, &usb_amradio_ctrl_ops,
528			  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
529	if (radio->hdl.error) {
530		retval = radio->hdl.error;
531		dev_err(&intf->dev, "couldn't register control\n");
532		goto err_ctrl;
533	}
534	mutex_init(&radio->lock);
535
536	radio->v4l2_dev.ctrl_handler = &radio->hdl;
537	radio->v4l2_dev.release = usb_amradio_release;
538	strscpy(radio->vdev.name, radio->v4l2_dev.name,
539		sizeof(radio->vdev.name));
540	radio->vdev.v4l2_dev = &radio->v4l2_dev;
541	radio->vdev.fops = &usb_amradio_fops;
542	radio->vdev.ioctl_ops = &usb_amradio_ioctl_ops;
543	radio->vdev.release = video_device_release_empty;
544	radio->vdev.lock = &radio->lock;
545	radio->vdev.device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER |
546				  V4L2_CAP_HW_FREQ_SEEK;
547
548	radio->usbdev = interface_to_usbdev(intf);
549	radio->intf = intf;
550	usb_set_intfdata(intf, &radio->v4l2_dev);
551	radio->curfreq = 95.16 * FREQ_MUL;
552
553	video_set_drvdata(&radio->vdev, radio);
554	retval = usb_amradio_init(radio);
555	if (retval)
556		goto err_vdev;
557
558	retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
559					radio_nr);
560	if (retval < 0) {
561		dev_err(&intf->dev, "could not register video device\n");
562		goto err_vdev;
563	}
564
565	return 0;
566
567err_vdev:
568	v4l2_ctrl_handler_free(&radio->hdl);
569err_ctrl:
570	v4l2_device_unregister(&radio->v4l2_dev);
571err_v4l2:
572	kfree(radio->buffer);
573err_nobuf:
574	kfree(radio);
575err:
576	return retval;
577}
578
579/* USB Device ID List */
580static const struct usb_device_id usb_amradio_device_table[] = {
581	{ USB_DEVICE_AND_INTERFACE_INFO(USB_AMRADIO_VENDOR, USB_AMRADIO_PRODUCT,
582							USB_CLASS_HID, 0, 0) },
583	{ }						/* Terminating entry */
584};
585
586MODULE_DEVICE_TABLE(usb, usb_amradio_device_table);
587
588/* USB subsystem interface */
589static struct usb_driver usb_amradio_driver = {
590	.name			= MR800_DRIVER_NAME,
591	.probe			= usb_amradio_probe,
592	.disconnect		= usb_amradio_disconnect,
593	.suspend		= usb_amradio_suspend,
594	.resume			= usb_amradio_resume,
595	.reset_resume		= usb_amradio_resume,
596	.id_table		= usb_amradio_device_table,
597};
598
599module_usb_driver(usb_amradio_driver);
600