1/*
2 * A driver for the AverMedia MR 800 USB FM radio. This device plugs
3 * into both the USB and an analog audio input, so this thing
4 * only deals with initialization and frequency setting, the
5 * audio data has to be handled by a sound driver.
6 *
7 * Copyright (c) 2008 Alexey Klimov <klimov.linux@gmail.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24/*
25 * Big thanks to authors and contributors of dsbr100.c and radio-si470x.c
26 *
27 * When work was looked pretty good, i discover this:
28 * http://av-usbradio.sourceforge.net/index.php
29 * http://sourceforge.net/projects/av-usbradio/
30 * Latest release of theirs project was in 2005.
31 * Probably, this driver could be improved through using their
32 * achievements (specifications given).
33 * Also, Faidon Liambotis <paravoid@debian.org> wrote nice driver for this radio
34 * in 2007. He allowed to use his driver to improve current mr800 radio driver.
35 * http://www.spinics.net/lists/linux-usb-devel/msg10109.html
36 *
37 * Version 0.01:	First working version.
38 * 			It's required to blacklist AverMedia USB Radio
39 * 			in usbhid/hid-quirks.c
40 * Version 0.10:	A lot of cleanups and fixes: unpluging the device,
41 * 			few mutex locks were added, codinstyle issues, etc.
42 * 			Added stereo support. Thanks to
43 * 			Douglas Schilling Landgraf <dougsland@gmail.com> and
44 * 			David Ellingsworth <david@identd.dyndns.org>
45 * 			for discussion, help and support.
46 * Version 0.11:	Converted to v4l2_device.
47 *
48 * Many things to do:
49 * 	- Correct power management of device (suspend & resume)
50 * 	- Add code for scanning and smooth tuning
51 * 	- Add code for sensitivity value
52 * 	- Correct mistakes
53 * 	- In Japan another FREQ_MIN and FREQ_MAX
54 */
55
56/* kernel includes */
57#include <linux/kernel.h>
58#include <linux/module.h>
59#include <linux/init.h>
60#include <linux/slab.h>
61#include <linux/input.h>
62#include <linux/videodev2.h>
63#include <media/v4l2-device.h>
64#include <media/v4l2-ioctl.h>
65#include <media/v4l2-ctrls.h>
66#include <media/v4l2-event.h>
67#include <linux/usb.h>
68#include <linux/mutex.h>
69
70/* driver and module definitions */
71#define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
72#define DRIVER_DESC "AverMedia MR 800 USB FM radio driver"
73#define DRIVER_VERSION "0.1.2"
74
75MODULE_AUTHOR(DRIVER_AUTHOR);
76MODULE_DESCRIPTION(DRIVER_DESC);
77MODULE_LICENSE("GPL");
78MODULE_VERSION(DRIVER_VERSION);
79
80#define USB_AMRADIO_VENDOR 0x07ca
81#define USB_AMRADIO_PRODUCT 0xb800
82
83/* dev_warn macro with driver name */
84#define MR800_DRIVER_NAME "radio-mr800"
85#define amradio_dev_warn(dev, fmt, arg...)				\
86		dev_warn(dev, MR800_DRIVER_NAME " - " fmt, ##arg)
87
88#define amradio_dev_err(dev, fmt, arg...) \
89		dev_err(dev, MR800_DRIVER_NAME " - " fmt, ##arg)
90
91/* Probably USB_TIMEOUT should be modified in module parameter */
92#define BUFFER_LENGTH 8
93#define USB_TIMEOUT 500
94
95/* Frequency limits in MHz -- these are European values.  For Japanese
96devices, that would be 76 and 91.  */
97#define FREQ_MIN  87.5
98#define FREQ_MAX 108.0
99#define FREQ_MUL 16000
100
101/*
102 * Commands that device should understand
103 * List isn't full and will be updated with implementation of new functions
104 */
105#define AMRADIO_SET_FREQ	0xa4
106#define AMRADIO_GET_READY_FLAG	0xa5
107#define AMRADIO_GET_SIGNAL	0xa7
108#define AMRADIO_GET_FREQ	0xa8
109#define AMRADIO_SET_SEARCH_UP	0xa9
110#define AMRADIO_SET_SEARCH_DOWN	0xaa
111#define AMRADIO_SET_MUTE	0xab
112#define AMRADIO_SET_RIGHT_MUTE	0xac
113#define AMRADIO_SET_LEFT_MUTE	0xad
114#define AMRADIO_SET_MONO	0xae
115#define AMRADIO_SET_SEARCH_LVL	0xb0
116#define AMRADIO_STOP_SEARCH	0xb1
117
118/* Comfortable defines for amradio_set_stereo */
119#define WANT_STEREO		0x00
120#define WANT_MONO		0x01
121
122/* module parameter */
123static int radio_nr = -1;
124module_param(radio_nr, int, 0);
125MODULE_PARM_DESC(radio_nr, "Radio Nr");
126
127/* Data for one (physical) device */
128struct amradio_device {
129	/* reference to USB and video device */
130	struct usb_device *usbdev;
131	struct usb_interface *intf;
132	struct video_device vdev;
133	struct v4l2_device v4l2_dev;
134	struct v4l2_ctrl_handler hdl;
135
136	u8 *buffer;
137	struct mutex lock;	/* buffer locking */
138	int curfreq;
139	int stereo;
140	int muted;
141};
142
143static inline struct amradio_device *to_amradio_dev(struct v4l2_device *v4l2_dev)
144{
145	return container_of(v4l2_dev, struct amradio_device, v4l2_dev);
146}
147
148static int amradio_send_cmd(struct amradio_device *radio, u8 cmd, u8 arg,
149		u8 *extra, u8 extralen, bool reply)
150{
151	int retval;
152	int size;
153
154	radio->buffer[0] = 0x00;
155	radio->buffer[1] = 0x55;
156	radio->buffer[2] = 0xaa;
157	radio->buffer[3] = extralen;
158	radio->buffer[4] = cmd;
159	radio->buffer[5] = arg;
160	radio->buffer[6] = 0x00;
161	radio->buffer[7] = extra || reply ? 8 : 0;
162
163	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
164		radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
165
166	if (retval < 0 || size != BUFFER_LENGTH) {
167		if (video_is_registered(&radio->vdev))
168			amradio_dev_warn(&radio->vdev.dev,
169					"cmd %02x failed\n", cmd);
170		return retval ? retval : -EIO;
171	}
172	if (!extra && !reply)
173		return 0;
174
175	if (extra) {
176		memcpy(radio->buffer, extra, extralen);
177		memset(radio->buffer + extralen, 0, 8 - extralen);
178		retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
179			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
180	} else {
181		memset(radio->buffer, 0, 8);
182		retval = usb_bulk_msg(radio->usbdev, usb_rcvbulkpipe(radio->usbdev, 0x81),
183			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
184	}
185	if (retval == 0 && size == BUFFER_LENGTH)
186		return 0;
187	if (video_is_registered(&radio->vdev) && cmd != AMRADIO_GET_READY_FLAG)
188		amradio_dev_warn(&radio->vdev.dev, "follow-up to cmd %02x failed\n", cmd);
189	return retval ? retval : -EIO;
190}
191
192/* switch on/off the radio. Send 8 bytes to device */
193static int amradio_set_mute(struct amradio_device *radio, bool mute)
194{
195	int ret = amradio_send_cmd(radio,
196			AMRADIO_SET_MUTE, mute, NULL, 0, false);
197
198	if (!ret)
199		radio->muted = mute;
200	return ret;
201}
202
203/* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
204static int amradio_set_freq(struct amradio_device *radio, int freq)
205{
206	unsigned short freq_send;
207	u8 buf[3];
208	int retval;
209
210	/* we need to be sure that frequency isn't out of range */
211	freq = clamp_t(unsigned, freq, FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL);
212	freq_send = 0x10 + (freq >> 3) / 25;
213
214	/* frequency is calculated from freq_send and placed in first 2 bytes */
215	buf[0] = (freq_send >> 8) & 0xff;
216	buf[1] = freq_send & 0xff;
217	buf[2] = 0x01;
218
219	retval = amradio_send_cmd(radio, AMRADIO_SET_FREQ, 0, buf, 3, false);
220	if (retval)
221		return retval;
222	radio->curfreq = freq;
223	msleep(40);
224	return 0;
225}
226
227static int amradio_set_stereo(struct amradio_device *radio, bool stereo)
228{
229	int ret = amradio_send_cmd(radio,
230			AMRADIO_SET_MONO, !stereo, NULL, 0, false);
231
232	if (!ret)
233		radio->stereo = stereo;
234	return ret;
235}
236
237static int amradio_get_stat(struct amradio_device *radio, bool *is_stereo, u32 *signal)
238{
239	int ret = amradio_send_cmd(radio,
240			AMRADIO_GET_SIGNAL, 0, NULL, 0, true);
241
242	if (ret)
243		return ret;
244	*is_stereo = radio->buffer[2] >> 7;
245	*signal = (radio->buffer[3] & 0xf0) << 8;
246	return 0;
247}
248
249/* Handle unplugging the device.
250 * We call video_unregister_device in any case.
251 * The last function called in this procedure is
252 * usb_amradio_device_release.
253 */
254static void usb_amradio_disconnect(struct usb_interface *intf)
255{
256	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
257
258	mutex_lock(&radio->lock);
259	video_unregister_device(&radio->vdev);
260	amradio_set_mute(radio, true);
261	usb_set_intfdata(intf, NULL);
262	v4l2_device_disconnect(&radio->v4l2_dev);
263	mutex_unlock(&radio->lock);
264	v4l2_device_put(&radio->v4l2_dev);
265}
266
267/* vidioc_querycap - query device capabilities */
268static int vidioc_querycap(struct file *file, void *priv,
269					struct v4l2_capability *v)
270{
271	struct amradio_device *radio = video_drvdata(file);
272
273	strlcpy(v->driver, "radio-mr800", sizeof(v->driver));
274	strlcpy(v->card, "AverMedia MR 800 USB FM Radio", sizeof(v->card));
275	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
276	v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER |
277					V4L2_CAP_HW_FREQ_SEEK;
278	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
279	return 0;
280}
281
282/* vidioc_g_tuner - get tuner attributes */
283static int vidioc_g_tuner(struct file *file, void *priv,
284				struct v4l2_tuner *v)
285{
286	struct amradio_device *radio = video_drvdata(file);
287	bool is_stereo = false;
288	int retval;
289
290	if (v->index > 0)
291		return -EINVAL;
292
293	v->signal = 0;
294	retval = amradio_get_stat(radio, &is_stereo, &v->signal);
295	if (retval)
296		return retval;
297
298	strcpy(v->name, "FM");
299	v->type = V4L2_TUNER_RADIO;
300	v->rangelow = FREQ_MIN * FREQ_MUL;
301	v->rangehigh = FREQ_MAX * FREQ_MUL;
302	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
303		V4L2_TUNER_CAP_HWSEEK_WRAP;
304	v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
305	v->audmode = radio->stereo ?
306		V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
307	return 0;
308}
309
310/* vidioc_s_tuner - set tuner attributes */
311static int vidioc_s_tuner(struct file *file, void *priv,
312				const struct v4l2_tuner *v)
313{
314	struct amradio_device *radio = video_drvdata(file);
315
316	if (v->index > 0)
317		return -EINVAL;
318
319	/* mono/stereo selector */
320	switch (v->audmode) {
321	case V4L2_TUNER_MODE_MONO:
322		return amradio_set_stereo(radio, WANT_MONO);
323	default:
324		return amradio_set_stereo(radio, WANT_STEREO);
325	}
326}
327
328/* vidioc_s_frequency - set tuner radio frequency */
329static int vidioc_s_frequency(struct file *file, void *priv,
330				const struct v4l2_frequency *f)
331{
332	struct amradio_device *radio = video_drvdata(file);
333
334	if (f->tuner != 0)
335		return -EINVAL;
336	return amradio_set_freq(radio, f->frequency);
337}
338
339/* vidioc_g_frequency - get tuner radio frequency */
340static int vidioc_g_frequency(struct file *file, void *priv,
341				struct v4l2_frequency *f)
342{
343	struct amradio_device *radio = video_drvdata(file);
344
345	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
346		return -EINVAL;
347	f->type = V4L2_TUNER_RADIO;
348	f->frequency = radio->curfreq;
349
350	return 0;
351}
352
353static int vidioc_s_hw_freq_seek(struct file *file, void *priv,
354		const struct v4l2_hw_freq_seek *seek)
355{
356	static u8 buf[8] = {
357		0x3d, 0x32, 0x0f, 0x08, 0x3d, 0x32, 0x0f, 0x08
358	};
359	struct amradio_device *radio = video_drvdata(file);
360	unsigned long timeout;
361	int retval;
362
363	if (seek->tuner != 0 || !seek->wrap_around)
364		return -EINVAL;
365
366	if (file->f_flags & O_NONBLOCK)
367		return -EWOULDBLOCK;
368
369	retval = amradio_send_cmd(radio,
370			AMRADIO_SET_SEARCH_LVL, 0, buf, 8, false);
371	if (retval)
372		return retval;
373	amradio_set_freq(radio, radio->curfreq);
374	retval = amradio_send_cmd(radio,
375		seek->seek_upward ? AMRADIO_SET_SEARCH_UP : AMRADIO_SET_SEARCH_DOWN,
376		0, NULL, 0, false);
377	if (retval)
378		return retval;
379	timeout = jiffies + msecs_to_jiffies(30000);
380	for (;;) {
381		if (time_after(jiffies, timeout)) {
382			retval = -ENODATA;
383			break;
384		}
385		if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
386			retval = -ERESTARTSYS;
387			break;
388		}
389		retval = amradio_send_cmd(radio, AMRADIO_GET_READY_FLAG,
390				0, NULL, 0, true);
391		if (retval)
392			continue;
393		amradio_send_cmd(radio, AMRADIO_GET_FREQ, 0, NULL, 0, true);
394		if (radio->buffer[1] || radio->buffer[2]) {
395			/* To check: sometimes radio->curfreq is set to out of range value */
396			radio->curfreq = (radio->buffer[1] << 8) | radio->buffer[2];
397			radio->curfreq = (radio->curfreq - 0x10) * 200;
398			amradio_send_cmd(radio, AMRADIO_STOP_SEARCH,
399					0, NULL, 0, false);
400			amradio_set_freq(radio, radio->curfreq);
401			retval = 0;
402			break;
403		}
404	}
405	amradio_send_cmd(radio, AMRADIO_STOP_SEARCH, 0, NULL, 0, false);
406	amradio_set_freq(radio, radio->curfreq);
407	return retval;
408}
409
410static int usb_amradio_s_ctrl(struct v4l2_ctrl *ctrl)
411{
412	struct amradio_device *radio =
413		container_of(ctrl->handler, struct amradio_device, hdl);
414
415	switch (ctrl->id) {
416	case V4L2_CID_AUDIO_MUTE:
417		return amradio_set_mute(radio, ctrl->val);
418	}
419
420	return -EINVAL;
421}
422
423static int usb_amradio_init(struct amradio_device *radio)
424{
425	int retval;
426
427	retval = amradio_set_mute(radio, true);
428	if (retval)
429		goto out_err;
430	retval = amradio_set_stereo(radio, true);
431	if (retval)
432		goto out_err;
433	retval = amradio_set_freq(radio, radio->curfreq);
434	if (retval)
435		goto out_err;
436	return 0;
437
438out_err:
439	amradio_dev_err(&radio->vdev.dev, "initialization failed\n");
440	return retval;
441}
442
443/* Suspend device - stop device. Need to be checked and fixed */
444static int usb_amradio_suspend(struct usb_interface *intf, pm_message_t message)
445{
446	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
447
448	mutex_lock(&radio->lock);
449	if (!radio->muted) {
450		amradio_set_mute(radio, true);
451		radio->muted = false;
452	}
453	mutex_unlock(&radio->lock);
454
455	dev_info(&intf->dev, "going into suspend..\n");
456	return 0;
457}
458
459/* Resume device - start device. Need to be checked and fixed */
460static int usb_amradio_resume(struct usb_interface *intf)
461{
462	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
463
464	mutex_lock(&radio->lock);
465	amradio_set_stereo(radio, radio->stereo);
466	amradio_set_freq(radio, radio->curfreq);
467
468	if (!radio->muted)
469		amradio_set_mute(radio, false);
470
471	mutex_unlock(&radio->lock);
472
473	dev_info(&intf->dev, "coming out of suspend..\n");
474	return 0;
475}
476
477static const struct v4l2_ctrl_ops usb_amradio_ctrl_ops = {
478	.s_ctrl = usb_amradio_s_ctrl,
479};
480
481/* File system interface */
482static const struct v4l2_file_operations usb_amradio_fops = {
483	.owner		= THIS_MODULE,
484	.open		= v4l2_fh_open,
485	.release	= v4l2_fh_release,
486	.poll		= v4l2_ctrl_poll,
487	.unlocked_ioctl	= video_ioctl2,
488};
489
490static const struct v4l2_ioctl_ops usb_amradio_ioctl_ops = {
491	.vidioc_querycap    = vidioc_querycap,
492	.vidioc_g_tuner     = vidioc_g_tuner,
493	.vidioc_s_tuner     = vidioc_s_tuner,
494	.vidioc_g_frequency = vidioc_g_frequency,
495	.vidioc_s_frequency = vidioc_s_frequency,
496	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
497	.vidioc_log_status  = v4l2_ctrl_log_status,
498	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
499	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
500};
501
502static void usb_amradio_release(struct v4l2_device *v4l2_dev)
503{
504	struct amradio_device *radio = to_amradio_dev(v4l2_dev);
505
506	/* free rest memory */
507	v4l2_ctrl_handler_free(&radio->hdl);
508	v4l2_device_unregister(&radio->v4l2_dev);
509	kfree(radio->buffer);
510	kfree(radio);
511}
512
513/* check if the device is present and register with v4l and usb if it is */
514static int usb_amradio_probe(struct usb_interface *intf,
515				const struct usb_device_id *id)
516{
517	struct amradio_device *radio;
518	int retval = 0;
519
520	radio = kzalloc(sizeof(struct amradio_device), GFP_KERNEL);
521
522	if (!radio) {
523		dev_err(&intf->dev, "kmalloc for amradio_device failed\n");
524		retval = -ENOMEM;
525		goto err;
526	}
527
528	radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
529
530	if (!radio->buffer) {
531		dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
532		retval = -ENOMEM;
533		goto err_nobuf;
534	}
535
536	retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
537	if (retval < 0) {
538		dev_err(&intf->dev, "couldn't register v4l2_device\n");
539		goto err_v4l2;
540	}
541
542	v4l2_ctrl_handler_init(&radio->hdl, 1);
543	v4l2_ctrl_new_std(&radio->hdl, &usb_amradio_ctrl_ops,
544			  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
545	if (radio->hdl.error) {
546		retval = radio->hdl.error;
547		dev_err(&intf->dev, "couldn't register control\n");
548		goto err_ctrl;
549	}
550	mutex_init(&radio->lock);
551
552	radio->v4l2_dev.ctrl_handler = &radio->hdl;
553	radio->v4l2_dev.release = usb_amradio_release;
554	strlcpy(radio->vdev.name, radio->v4l2_dev.name,
555		sizeof(radio->vdev.name));
556	radio->vdev.v4l2_dev = &radio->v4l2_dev;
557	radio->vdev.fops = &usb_amradio_fops;
558	radio->vdev.ioctl_ops = &usb_amradio_ioctl_ops;
559	radio->vdev.release = video_device_release_empty;
560	radio->vdev.lock = &radio->lock;
561
562	radio->usbdev = interface_to_usbdev(intf);
563	radio->intf = intf;
564	usb_set_intfdata(intf, &radio->v4l2_dev);
565	radio->curfreq = 95.16 * FREQ_MUL;
566
567	video_set_drvdata(&radio->vdev, radio);
568	retval = usb_amradio_init(radio);
569	if (retval)
570		goto err_vdev;
571
572	retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
573					radio_nr);
574	if (retval < 0) {
575		dev_err(&intf->dev, "could not register video device\n");
576		goto err_vdev;
577	}
578
579	return 0;
580
581err_vdev:
582	v4l2_ctrl_handler_free(&radio->hdl);
583err_ctrl:
584	v4l2_device_unregister(&radio->v4l2_dev);
585err_v4l2:
586	kfree(radio->buffer);
587err_nobuf:
588	kfree(radio);
589err:
590	return retval;
591}
592
593/* USB Device ID List */
594static struct usb_device_id usb_amradio_device_table[] = {
595	{ USB_DEVICE_AND_INTERFACE_INFO(USB_AMRADIO_VENDOR, USB_AMRADIO_PRODUCT,
596							USB_CLASS_HID, 0, 0) },
597	{ }						/* Terminating entry */
598};
599
600MODULE_DEVICE_TABLE(usb, usb_amradio_device_table);
601
602/* USB subsystem interface */
603static struct usb_driver usb_amradio_driver = {
604	.name			= MR800_DRIVER_NAME,
605	.probe			= usb_amradio_probe,
606	.disconnect		= usb_amradio_disconnect,
607	.suspend		= usb_amradio_suspend,
608	.resume			= usb_amradio_resume,
609	.reset_resume		= usb_amradio_resume,
610	.id_table		= usb_amradio_device_table,
611};
612
613module_usb_driver(usb_amradio_driver);
614