1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2013 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
4 */
5
6#include <linux/kernel.h>
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/slab.h>
10#include <linux/input.h>
11#include <linux/usb.h>
12#include <linux/hid.h>
13#include <linux/mutex.h>
14#include <linux/videodev2.h>
15#include <asm/unaligned.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
21/*
22 * 'Thanko's Raremono' is a Japanese si4734-based AM/FM/SW USB receiver:
23 *
24 * http://www.raremono.jp/product/484.html/
25 *
26 * The USB protocol has been reversed engineered using wireshark, initially
27 * by Dinesh Ram <dinesh.ram@cern.ch> and finished by Hans Verkuil
28 * <hverkuil@xs4all.nl>.
29 *
30 * Sadly the firmware used in this product hides lots of goodies since the
31 * si4734 has more features than are supported by the firmware. Oh well...
32 */
33
34/* driver and module definitions */
35MODULE_AUTHOR("Hans Verkuil <hverkuil@xs4all.nl>");
36MODULE_DESCRIPTION("Thanko's Raremono AM/FM/SW Receiver USB driver");
37MODULE_LICENSE("GPL v2");
38
39/*
40 * The Device announces itself as Cygnal Integrated Products, Inc.
41 *
42 * The vendor and product IDs (and in fact all other lsusb information as
43 * well) are identical to the si470x Silicon Labs USB FM Radio Reference
44 * Design board, even though this card has a si4734 device. Clearly the
45 * designer of this product never bothered to change the USB IDs.
46 */
47
48/* USB Device ID List */
49static const struct usb_device_id usb_raremono_device_table[] = {
50	{USB_DEVICE_AND_INTERFACE_INFO(0x10c4, 0x818a, USB_CLASS_HID, 0, 0) },
51	{ }						/* Terminating entry */
52};
53
54MODULE_DEVICE_TABLE(usb, usb_raremono_device_table);
55
56#define BUFFER_LENGTH 64
57
58/* Timeout is set to a high value, could probably be reduced. Need more tests */
59#define USB_TIMEOUT 10000
60
61/* Frequency limits in KHz */
62#define FM_FREQ_RANGE_LOW	64000
63#define FM_FREQ_RANGE_HIGH	108000
64
65#define AM_FREQ_RANGE_LOW	520
66#define AM_FREQ_RANGE_HIGH	1710
67
68#define SW_FREQ_RANGE_LOW	2300
69#define SW_FREQ_RANGE_HIGH	26100
70
71enum { BAND_FM, BAND_AM, BAND_SW };
72
73static const struct v4l2_frequency_band bands[] = {
74	/* Band FM */
75	{
76		.type = V4L2_TUNER_RADIO,
77		.index = 0,
78		.capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
79			      V4L2_TUNER_CAP_FREQ_BANDS,
80		.rangelow   = FM_FREQ_RANGE_LOW * 16,
81		.rangehigh  = FM_FREQ_RANGE_HIGH * 16,
82		.modulation = V4L2_BAND_MODULATION_FM,
83	},
84	/* Band AM */
85	{
86		.type = V4L2_TUNER_RADIO,
87		.index = 1,
88		.capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS,
89		.rangelow   = AM_FREQ_RANGE_LOW * 16,
90		.rangehigh  = AM_FREQ_RANGE_HIGH * 16,
91		.modulation = V4L2_BAND_MODULATION_AM,
92	},
93	/* Band SW */
94	{
95		.type = V4L2_TUNER_RADIO,
96		.index = 2,
97		.capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_FREQ_BANDS,
98		.rangelow   = SW_FREQ_RANGE_LOW * 16,
99		.rangehigh  = SW_FREQ_RANGE_HIGH * 16,
100		.modulation = V4L2_BAND_MODULATION_AM,
101	},
102};
103
104struct raremono_device {
105	struct usb_device *usbdev;
106	struct usb_interface *intf;
107	struct video_device vdev;
108	struct v4l2_device v4l2_dev;
109	struct mutex lock;
110
111	u8 *buffer;
112	u32 band;
113	unsigned curfreq;
114};
115
116static inline struct raremono_device *to_raremono_dev(struct v4l2_device *v4l2_dev)
117{
118	return container_of(v4l2_dev, struct raremono_device, v4l2_dev);
119}
120
121/* Set frequency. */
122static int raremono_cmd_main(struct raremono_device *radio, unsigned band, unsigned freq)
123{
124	unsigned band_offset;
125	int ret;
126
127	switch (band) {
128	case BAND_FM:
129		band_offset = 1;
130		freq /= 10;
131		break;
132	case BAND_AM:
133		band_offset = 0;
134		break;
135	default:
136		band_offset = 2;
137		break;
138	}
139	radio->buffer[0] = 0x04 + band_offset;
140	radio->buffer[1] = freq >> 8;
141	radio->buffer[2] = freq & 0xff;
142
143	ret = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
144			HID_REQ_SET_REPORT,
145			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
146			0x0300 + radio->buffer[0], 2,
147			radio->buffer, 3, USB_TIMEOUT);
148
149	if (ret < 0) {
150		dev_warn(radio->v4l2_dev.dev, "%s failed (%d)\n", __func__, ret);
151		return ret;
152	}
153	radio->curfreq = (band == BAND_FM) ? freq * 10 : freq;
154	return 0;
155}
156
157/* Handle unplugging the device.
158 * We call video_unregister_device in any case.
159 * The last function called in this procedure is
160 * usb_raremono_device_release.
161 */
162static void usb_raremono_disconnect(struct usb_interface *intf)
163{
164	struct raremono_device *radio = to_raremono_dev(usb_get_intfdata(intf));
165
166	dev_info(&intf->dev, "Thanko's Raremono disconnected\n");
167
168	mutex_lock(&radio->lock);
169	usb_set_intfdata(intf, NULL);
170	video_unregister_device(&radio->vdev);
171	v4l2_device_disconnect(&radio->v4l2_dev);
172	mutex_unlock(&radio->lock);
173	v4l2_device_put(&radio->v4l2_dev);
174}
175
176/*
177 * Linux Video interface
178 */
179static int vidioc_querycap(struct file *file, void *priv,
180					struct v4l2_capability *v)
181{
182	struct raremono_device *radio = video_drvdata(file);
183
184	strscpy(v->driver, "radio-raremono", sizeof(v->driver));
185	strscpy(v->card, "Thanko's Raremono", sizeof(v->card));
186	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
187	return 0;
188}
189
190static int vidioc_enum_freq_bands(struct file *file, void *priv,
191		struct v4l2_frequency_band *band)
192{
193	if (band->tuner != 0)
194		return -EINVAL;
195
196	if (band->index >= ARRAY_SIZE(bands))
197		return -EINVAL;
198
199	*band = bands[band->index];
200
201	return 0;
202}
203
204static int vidioc_g_tuner(struct file *file, void *priv,
205		struct v4l2_tuner *v)
206{
207	struct raremono_device *radio = video_drvdata(file);
208	int ret;
209
210	if (v->index > 0)
211		return -EINVAL;
212
213	strscpy(v->name, "AM/FM/SW", sizeof(v->name));
214	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
215		V4L2_TUNER_CAP_FREQ_BANDS;
216	v->rangelow = AM_FREQ_RANGE_LOW * 16;
217	v->rangehigh = FM_FREQ_RANGE_HIGH * 16;
218	v->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO;
219	v->audmode = (radio->curfreq < FM_FREQ_RANGE_LOW) ?
220		V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO;
221	memset(radio->buffer, 1, BUFFER_LENGTH);
222	ret = usb_control_msg(radio->usbdev, usb_rcvctrlpipe(radio->usbdev, 0),
223			1, 0xa1, 0x030d, 2, radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
224
225	if (ret < 0) {
226		dev_warn(radio->v4l2_dev.dev, "%s failed (%d)\n", __func__, ret);
227		return ret;
228	}
229	v->signal = ((radio->buffer[1] & 0xf) << 8 | radio->buffer[2]) << 4;
230	return 0;
231}
232
233static int vidioc_s_tuner(struct file *file, void *priv,
234					const struct v4l2_tuner *v)
235{
236	return v->index ? -EINVAL : 0;
237}
238
239static int vidioc_s_frequency(struct file *file, void *priv,
240				const struct v4l2_frequency *f)
241{
242	struct raremono_device *radio = video_drvdata(file);
243	u32 freq;
244	unsigned band;
245
246	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
247		return -EINVAL;
248
249	if (f->frequency >= (FM_FREQ_RANGE_LOW + SW_FREQ_RANGE_HIGH) * 8)
250		band = BAND_FM;
251	else if (f->frequency <= (AM_FREQ_RANGE_HIGH + SW_FREQ_RANGE_LOW) * 8)
252		band = BAND_AM;
253	else
254		band = BAND_SW;
255
256	freq = clamp_t(u32, f->frequency, bands[band].rangelow, bands[band].rangehigh);
257	return raremono_cmd_main(radio, band, freq / 16);
258}
259
260static int vidioc_g_frequency(struct file *file, void *priv,
261				struct v4l2_frequency *f)
262{
263	struct raremono_device *radio = video_drvdata(file);
264
265	if (f->tuner != 0)
266		return -EINVAL;
267	f->type = V4L2_TUNER_RADIO;
268	f->frequency = radio->curfreq * 16;
269	return 0;
270}
271
272static void raremono_device_release(struct v4l2_device *v4l2_dev)
273{
274	struct raremono_device *radio = to_raremono_dev(v4l2_dev);
275
276	kfree(radio->buffer);
277	kfree(radio);
278}
279
280/* File system interface */
281static const struct v4l2_file_operations usb_raremono_fops = {
282	.owner		= THIS_MODULE,
283	.open           = v4l2_fh_open,
284	.release        = v4l2_fh_release,
285	.unlocked_ioctl	= video_ioctl2,
286};
287
288static const struct v4l2_ioctl_ops usb_raremono_ioctl_ops = {
289	.vidioc_querycap = vidioc_querycap,
290	.vidioc_g_tuner = vidioc_g_tuner,
291	.vidioc_s_tuner = vidioc_s_tuner,
292	.vidioc_g_frequency = vidioc_g_frequency,
293	.vidioc_s_frequency = vidioc_s_frequency,
294	.vidioc_enum_freq_bands = vidioc_enum_freq_bands,
295};
296
297/* check if the device is present and register with v4l and usb if it is */
298static int usb_raremono_probe(struct usb_interface *intf,
299				const struct usb_device_id *id)
300{
301	struct raremono_device *radio;
302	int retval = 0;
303
304	radio = kzalloc(sizeof(*radio), GFP_KERNEL);
305	if (!radio)
306		return -ENOMEM;
307	radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
308	if (!radio->buffer) {
309		kfree(radio);
310		return -ENOMEM;
311	}
312
313	radio->usbdev = interface_to_usbdev(intf);
314	radio->intf = intf;
315
316	/*
317	 * This device uses the same USB IDs as the si470x SiLabs reference
318	 * design. So do an additional check: attempt to read the device ID
319	 * from the si470x: the lower 12 bits are 0x0242 for the si470x. The
320	 * Raremono always returns 0x0800 (the meaning of that is unknown, but
321	 * at least it works).
322	 *
323	 * We use this check to determine which device we are dealing with.
324	 */
325	msleep(20);
326	retval = usb_control_msg(radio->usbdev,
327		usb_rcvctrlpipe(radio->usbdev, 0),
328		HID_REQ_GET_REPORT,
329		USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
330		1, 2,
331		radio->buffer, 3, 500);
332	if (retval != 3 ||
333	    (get_unaligned_be16(&radio->buffer[1]) & 0xfff) == 0x0242) {
334		dev_info(&intf->dev, "this is not Thanko's Raremono.\n");
335		retval = -ENODEV;
336		goto free_mem;
337	}
338
339	dev_info(&intf->dev, "Thanko's Raremono connected: (%04X:%04X)\n",
340			id->idVendor, id->idProduct);
341
342	retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
343	if (retval < 0) {
344		dev_err(&intf->dev, "couldn't register v4l2_device\n");
345		goto free_mem;
346	}
347
348	mutex_init(&radio->lock);
349
350	strscpy(radio->vdev.name, radio->v4l2_dev.name,
351		sizeof(radio->vdev.name));
352	radio->vdev.v4l2_dev = &radio->v4l2_dev;
353	radio->vdev.fops = &usb_raremono_fops;
354	radio->vdev.ioctl_ops = &usb_raremono_ioctl_ops;
355	radio->vdev.lock = &radio->lock;
356	radio->vdev.release = video_device_release_empty;
357	radio->vdev.device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
358	radio->v4l2_dev.release = raremono_device_release;
359
360	usb_set_intfdata(intf, &radio->v4l2_dev);
361
362	video_set_drvdata(&radio->vdev, radio);
363
364	raremono_cmd_main(radio, BAND_FM, 95160);
365
366	retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);
367	if (retval == 0) {
368		dev_info(&intf->dev, "V4L2 device registered as %s\n",
369				video_device_node_name(&radio->vdev));
370		return 0;
371	}
372	dev_err(&intf->dev, "could not register video device\n");
373	v4l2_device_unregister(&radio->v4l2_dev);
374
375free_mem:
376	kfree(radio->buffer);
377	kfree(radio);
378	return retval;
379}
380
381/* USB subsystem interface */
382static struct usb_driver usb_raremono_driver = {
383	.name			= "radio-raremono",
384	.probe			= usb_raremono_probe,
385	.disconnect		= usb_raremono_disconnect,
386	.id_table		= usb_raremono_device_table,
387};
388
389module_usb_driver(usb_raremono_driver);
390