xref: /linux/drivers/media/radio/radio-ma901.c (revision 44f57d78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for the MasterKit MA901 USB FM radio. This device plugs
4  * into the USB port and an analog audio input or headphones, so this thing
5  * only deals with initialization, frequency setting, volume.
6  *
7  * Copyright (c) 2012 Alexey Klimov <klimov.linux@gmail.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/slab.h>
14 #include <linux/input.h>
15 #include <linux/videodev2.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 #include <linux/usb.h>
21 #include <linux/mutex.h>
22 
23 #define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
24 #define DRIVER_DESC "Masterkit MA901 USB FM radio driver"
25 #define DRIVER_VERSION "0.0.1"
26 
27 MODULE_AUTHOR(DRIVER_AUTHOR);
28 MODULE_DESCRIPTION(DRIVER_DESC);
29 MODULE_LICENSE("GPL");
30 MODULE_VERSION(DRIVER_VERSION);
31 
32 #define USB_MA901_VENDOR  0x16c0
33 #define USB_MA901_PRODUCT 0x05df
34 
35 /* dev_warn macro with driver name */
36 #define MA901_DRIVER_NAME "radio-ma901"
37 #define ma901radio_dev_warn(dev, fmt, arg...)				\
38 		dev_warn(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
39 
40 #define ma901radio_dev_err(dev, fmt, arg...) \
41 		dev_err(dev, MA901_DRIVER_NAME " - " fmt, ##arg)
42 
43 /* Probably USB_TIMEOUT should be modified in module parameter */
44 #define BUFFER_LENGTH 8
45 #define USB_TIMEOUT 500
46 
47 #define FREQ_MIN  87.5
48 #define FREQ_MAX 108.0
49 #define FREQ_MUL 16000
50 
51 #define MA901_VOLUME_MAX 16
52 #define MA901_VOLUME_MIN 0
53 
54 /* Commands that device should understand
55  * List isn't full and will be updated with implementation of new functions
56  */
57 #define MA901_RADIO_SET_FREQ		0x03
58 #define MA901_RADIO_SET_VOLUME		0x04
59 #define MA901_RADIO_SET_MONO_STEREO	0x05
60 
61 /* Comfortable defines for ma901radio_set_stereo */
62 #define MA901_WANT_STEREO		0x50
63 #define MA901_WANT_MONO			0xd0
64 
65 /* module parameter */
66 static int radio_nr = -1;
67 module_param(radio_nr, int, 0);
68 MODULE_PARM_DESC(radio_nr, "Radio file number");
69 
70 /* Data for one (physical) device */
71 struct ma901radio_device {
72 	/* reference to USB and video device */
73 	struct usb_device *usbdev;
74 	struct usb_interface *intf;
75 	struct video_device vdev;
76 	struct v4l2_device v4l2_dev;
77 	struct v4l2_ctrl_handler hdl;
78 
79 	u8 *buffer;
80 	struct mutex lock;	/* buffer locking */
81 	int curfreq;
82 	u16 volume;
83 	int stereo;
84 	bool muted;
85 };
86 
87 static inline struct ma901radio_device *to_ma901radio_dev(struct v4l2_device *v4l2_dev)
88 {
89 	return container_of(v4l2_dev, struct ma901radio_device, v4l2_dev);
90 }
91 
92 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
93 static int ma901radio_set_freq(struct ma901radio_device *radio, int freq)
94 {
95 	unsigned int freq_send = 0x300 + (freq >> 5) / 25;
96 	int retval;
97 
98 	radio->buffer[0] = 0x0a;
99 	radio->buffer[1] = MA901_RADIO_SET_FREQ;
100 	radio->buffer[2] = ((freq_send >> 8) & 0xff) + 0x80;
101 	radio->buffer[3] = freq_send & 0xff;
102 	radio->buffer[4] = 0x00;
103 	radio->buffer[5] = 0x00;
104 	radio->buffer[6] = 0x00;
105 	radio->buffer[7] = 0x00;
106 
107 	retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
108 				9, 0x21, 0x0300, 0,
109 				radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
110 	if (retval < 0)
111 		return retval;
112 
113 	radio->curfreq = freq;
114 	return 0;
115 }
116 
117 static int ma901radio_set_volume(struct ma901radio_device *radio, u16 vol_to_set)
118 {
119 	int retval;
120 
121 	radio->buffer[0] = 0x0a;
122 	radio->buffer[1] = MA901_RADIO_SET_VOLUME;
123 	radio->buffer[2] = 0xc2;
124 	radio->buffer[3] = vol_to_set + 0x20;
125 	radio->buffer[4] = 0x00;
126 	radio->buffer[5] = 0x00;
127 	radio->buffer[6] = 0x00;
128 	radio->buffer[7] = 0x00;
129 
130 	retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
131 				9, 0x21, 0x0300, 0,
132 				radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
133 	if (retval < 0)
134 		return retval;
135 
136 	radio->volume = vol_to_set;
137 	return retval;
138 }
139 
140 static int ma901_set_stereo(struct ma901radio_device *radio, u8 stereo)
141 {
142 	int retval;
143 
144 	radio->buffer[0] = 0x0a;
145 	radio->buffer[1] = MA901_RADIO_SET_MONO_STEREO;
146 	radio->buffer[2] = stereo;
147 	radio->buffer[3] = 0x00;
148 	radio->buffer[4] = 0x00;
149 	radio->buffer[5] = 0x00;
150 	radio->buffer[6] = 0x00;
151 	radio->buffer[7] = 0x00;
152 
153 	retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
154 				9, 0x21, 0x0300, 0,
155 				radio->buffer, BUFFER_LENGTH, USB_TIMEOUT);
156 
157 	if (retval < 0)
158 		return retval;
159 
160 	if (stereo == MA901_WANT_STEREO)
161 		radio->stereo = V4L2_TUNER_MODE_STEREO;
162 	else
163 		radio->stereo = V4L2_TUNER_MODE_MONO;
164 
165 	return retval;
166 }
167 
168 /* Handle unplugging the device.
169  * We call video_unregister_device in any case.
170  * The last function called in this procedure is
171  * usb_ma901radio_device_release.
172  */
173 static void usb_ma901radio_disconnect(struct usb_interface *intf)
174 {
175 	struct ma901radio_device *radio = to_ma901radio_dev(usb_get_intfdata(intf));
176 
177 	mutex_lock(&radio->lock);
178 	video_unregister_device(&radio->vdev);
179 	usb_set_intfdata(intf, NULL);
180 	v4l2_device_disconnect(&radio->v4l2_dev);
181 	mutex_unlock(&radio->lock);
182 	v4l2_device_put(&radio->v4l2_dev);
183 }
184 
185 /* vidioc_querycap - query device capabilities */
186 static int vidioc_querycap(struct file *file, void *priv,
187 					struct v4l2_capability *v)
188 {
189 	struct ma901radio_device *radio = video_drvdata(file);
190 
191 	strscpy(v->driver, "radio-ma901", sizeof(v->driver));
192 	strscpy(v->card, "Masterkit MA901 USB FM Radio", sizeof(v->card));
193 	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
194 	v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
195 	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
196 	return 0;
197 }
198 
199 /* vidioc_g_tuner - get tuner attributes */
200 static int vidioc_g_tuner(struct file *file, void *priv,
201 				struct v4l2_tuner *v)
202 {
203 	struct ma901radio_device *radio = video_drvdata(file);
204 
205 	if (v->index > 0)
206 		return -EINVAL;
207 
208 	v->signal = 0;
209 
210 	/* TODO: the same words like in _probe() goes here.
211 	 * When receiving of stats will be implemented then we can call
212 	 * ma901radio_get_stat().
213 	 * retval = ma901radio_get_stat(radio, &is_stereo, &v->signal);
214 	 */
215 
216 	strscpy(v->name, "FM", sizeof(v->name));
217 	v->type = V4L2_TUNER_RADIO;
218 	v->rangelow = FREQ_MIN * FREQ_MUL;
219 	v->rangehigh = FREQ_MAX * FREQ_MUL;
220 	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
221 	/* v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO; */
222 	v->audmode = radio->stereo ?
223 		V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
224 	return 0;
225 }
226 
227 /* vidioc_s_tuner - set tuner attributes */
228 static int vidioc_s_tuner(struct file *file, void *priv,
229 				const struct v4l2_tuner *v)
230 {
231 	struct ma901radio_device *radio = video_drvdata(file);
232 
233 	if (v->index > 0)
234 		return -EINVAL;
235 
236 	/* mono/stereo selector */
237 	switch (v->audmode) {
238 	case V4L2_TUNER_MODE_MONO:
239 		return ma901_set_stereo(radio, MA901_WANT_MONO);
240 	default:
241 		return ma901_set_stereo(radio, MA901_WANT_STEREO);
242 	}
243 }
244 
245 /* vidioc_s_frequency - set tuner radio frequency */
246 static int vidioc_s_frequency(struct file *file, void *priv,
247 				const struct v4l2_frequency *f)
248 {
249 	struct ma901radio_device *radio = video_drvdata(file);
250 
251 	if (f->tuner != 0)
252 		return -EINVAL;
253 
254 	return ma901radio_set_freq(radio, clamp_t(unsigned, f->frequency,
255 				FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL));
256 }
257 
258 /* vidioc_g_frequency - get tuner radio frequency */
259 static int vidioc_g_frequency(struct file *file, void *priv,
260 				struct v4l2_frequency *f)
261 {
262 	struct ma901radio_device *radio = video_drvdata(file);
263 
264 	if (f->tuner != 0)
265 		return -EINVAL;
266 	f->frequency = radio->curfreq;
267 
268 	return 0;
269 }
270 
271 static int usb_ma901radio_s_ctrl(struct v4l2_ctrl *ctrl)
272 {
273 	struct ma901radio_device *radio =
274 		container_of(ctrl->handler, struct ma901radio_device, hdl);
275 
276 	switch (ctrl->id) {
277 	case V4L2_CID_AUDIO_VOLUME:     /* set volume */
278 		return ma901radio_set_volume(radio, (u16)ctrl->val);
279 	}
280 
281 	return -EINVAL;
282 }
283 
284 /* TODO: Should we really need to implement suspend and resume functions?
285  * Radio has it's own memory and will continue playing if power is present
286  * on usb port and on resume it will start to play again based on freq, volume
287  * values in device memory.
288  */
289 static int usb_ma901radio_suspend(struct usb_interface *intf, pm_message_t message)
290 {
291 	return 0;
292 }
293 
294 static int usb_ma901radio_resume(struct usb_interface *intf)
295 {
296 	return 0;
297 }
298 
299 static const struct v4l2_ctrl_ops usb_ma901radio_ctrl_ops = {
300 	.s_ctrl = usb_ma901radio_s_ctrl,
301 };
302 
303 /* File system interface */
304 static const struct v4l2_file_operations usb_ma901radio_fops = {
305 	.owner		= THIS_MODULE,
306 	.open		= v4l2_fh_open,
307 	.release	= v4l2_fh_release,
308 	.poll		= v4l2_ctrl_poll,
309 	.unlocked_ioctl	= video_ioctl2,
310 };
311 
312 static const struct v4l2_ioctl_ops usb_ma901radio_ioctl_ops = {
313 	.vidioc_querycap    = vidioc_querycap,
314 	.vidioc_g_tuner     = vidioc_g_tuner,
315 	.vidioc_s_tuner     = vidioc_s_tuner,
316 	.vidioc_g_frequency = vidioc_g_frequency,
317 	.vidioc_s_frequency = vidioc_s_frequency,
318 	.vidioc_log_status  = v4l2_ctrl_log_status,
319 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
320 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
321 };
322 
323 static void usb_ma901radio_release(struct v4l2_device *v4l2_dev)
324 {
325 	struct ma901radio_device *radio = to_ma901radio_dev(v4l2_dev);
326 
327 	v4l2_ctrl_handler_free(&radio->hdl);
328 	v4l2_device_unregister(&radio->v4l2_dev);
329 	kfree(radio->buffer);
330 	kfree(radio);
331 }
332 
333 /* check if the device is present and register with v4l and usb if it is */
334 static int usb_ma901radio_probe(struct usb_interface *intf,
335 				const struct usb_device_id *id)
336 {
337 	struct usb_device *dev = interface_to_usbdev(intf);
338 	struct ma901radio_device *radio;
339 	int retval = 0;
340 
341 	/* Masterkit MA901 usb radio has the same USB ID as many others
342 	 * Atmel V-USB devices. Let's make additional checks to be sure
343 	 * that this is our device.
344 	 */
345 
346 	if (dev->product && dev->manufacturer &&
347 		(strncmp(dev->product, "MA901", 5) != 0
348 		|| strncmp(dev->manufacturer, "www.masterkit.ru", 16) != 0))
349 		return -ENODEV;
350 
351 	radio = kzalloc(sizeof(struct ma901radio_device), GFP_KERNEL);
352 	if (!radio) {
353 		dev_err(&intf->dev, "kzalloc for ma901radio_device failed\n");
354 		retval = -ENOMEM;
355 		goto err;
356 	}
357 
358 	radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
359 	if (!radio->buffer) {
360 		dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
361 		retval = -ENOMEM;
362 		goto err_nobuf;
363 	}
364 
365 	retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
366 	if (retval < 0) {
367 		dev_err(&intf->dev, "couldn't register v4l2_device\n");
368 		goto err_v4l2;
369 	}
370 
371 	v4l2_ctrl_handler_init(&radio->hdl, 1);
372 
373 	/* TODO:It looks like this radio doesn't have mute/unmute control
374 	 * and windows program just emulate it using volume control.
375 	 * Let's plan to do the same in this driver.
376 	 *
377 	 * v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
378 	 *		  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
379 	 */
380 
381 	v4l2_ctrl_new_std(&radio->hdl, &usb_ma901radio_ctrl_ops,
382 			  V4L2_CID_AUDIO_VOLUME, MA901_VOLUME_MIN,
383 			  MA901_VOLUME_MAX, 1, MA901_VOLUME_MAX);
384 
385 	if (radio->hdl.error) {
386 		retval = radio->hdl.error;
387 		dev_err(&intf->dev, "couldn't register control\n");
388 		goto err_ctrl;
389 	}
390 	mutex_init(&radio->lock);
391 
392 	radio->v4l2_dev.ctrl_handler = &radio->hdl;
393 	radio->v4l2_dev.release = usb_ma901radio_release;
394 	strscpy(radio->vdev.name, radio->v4l2_dev.name,
395 		sizeof(radio->vdev.name));
396 	radio->vdev.v4l2_dev = &radio->v4l2_dev;
397 	radio->vdev.fops = &usb_ma901radio_fops;
398 	radio->vdev.ioctl_ops = &usb_ma901radio_ioctl_ops;
399 	radio->vdev.release = video_device_release_empty;
400 	radio->vdev.lock = &radio->lock;
401 
402 	radio->usbdev = interface_to_usbdev(intf);
403 	radio->intf = intf;
404 	usb_set_intfdata(intf, &radio->v4l2_dev);
405 	radio->curfreq = 95.21 * FREQ_MUL;
406 
407 	video_set_drvdata(&radio->vdev, radio);
408 
409 	/* TODO: we can get some statistics (freq, volume) from device
410 	 * but it's not implemented yet. After insertion in usb-port radio
411 	 * setups frequency and starts playing without any initialization.
412 	 * So we don't call usb_ma901radio_init/get_stat() here.
413 	 * retval = usb_ma901radio_init(radio);
414 	 */
415 
416 	retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
417 					radio_nr);
418 	if (retval < 0) {
419 		dev_err(&intf->dev, "could not register video device\n");
420 		goto err_vdev;
421 	}
422 
423 	return 0;
424 
425 err_vdev:
426 	v4l2_ctrl_handler_free(&radio->hdl);
427 err_ctrl:
428 	v4l2_device_unregister(&radio->v4l2_dev);
429 err_v4l2:
430 	kfree(radio->buffer);
431 err_nobuf:
432 	kfree(radio);
433 err:
434 	return retval;
435 }
436 
437 /* USB Device ID List */
438 static const struct usb_device_id usb_ma901radio_device_table[] = {
439 	{ USB_DEVICE_AND_INTERFACE_INFO(USB_MA901_VENDOR, USB_MA901_PRODUCT,
440 							USB_CLASS_HID, 0, 0) },
441 	{ }						/* Terminating entry */
442 };
443 
444 MODULE_DEVICE_TABLE(usb, usb_ma901radio_device_table);
445 
446 /* USB subsystem interface */
447 static struct usb_driver usb_ma901radio_driver = {
448 	.name			= MA901_DRIVER_NAME,
449 	.probe			= usb_ma901radio_probe,
450 	.disconnect		= usb_ma901radio_disconnect,
451 	.suspend		= usb_ma901radio_suspend,
452 	.resume			= usb_ma901radio_resume,
453 	.reset_resume		= usb_ma901radio_resume,
454 	.id_table		= usb_ma901radio_device_table,
455 };
456 
457 module_usb_driver(usb_ma901radio_driver);
458