xref: /openbmc/linux/drivers/media/radio/radio-typhoon.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /* Typhoon Radio Card driver for radio support
2  * (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de>
3  *
4  * Card manufacturer:
5  * http://194.18.155.92/idc/prod2.idc?nr=50753&lang=e
6  *
7  * Notes on the hardware
8  *
9  * This card has two output sockets, one for speakers and one for line.
10  * The speaker output has volume control, but only in four discrete
11  * steps. The line output has neither volume control nor mute.
12  *
13  * The card has auto-stereo according to its manual, although it all
14  * sounds mono to me (even with the Win/DOS drivers). Maybe it's my
15  * antenna - I really don't know for sure.
16  *
17  * Frequency control is done digitally.
18  *
19  * Volume control is done digitally, but there are only four different
20  * possible values. So you should better always turn the volume up and
21  * use line control. I got the best results by connecting line output
22  * to the sound card microphone input. For such a configuration the
23  * volume control has no effect, since volume control only influences
24  * the speaker output.
25  *
26  * There is no explicit mute/unmute. So I set the radio frequency to a
27  * value where I do expect just noise and turn the speaker volume down.
28  * The frequency change is necessary since the card never seems to be
29  * completely silent.
30  *
31  * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>
32  */
33 
34 #include <linux/module.h>	/* Modules                        */
35 #include <linux/init.h>		/* Initdata                       */
36 #include <linux/ioport.h>	/* request_region		  */
37 #include <linux/version.h>      /* for KERNEL_VERSION MACRO     */
38 #include <linux/videodev2.h>	/* kernel radio structs           */
39 #include <linux/io.h>		/* outb, outb_p                   */
40 #include <media/v4l2-device.h>
41 #include <media/v4l2-ioctl.h>
42 
43 MODULE_AUTHOR("Dr. Henrik Seidel");
44 MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");
45 MODULE_LICENSE("GPL");
46 
47 #ifndef CONFIG_RADIO_TYPHOON_PORT
48 #define CONFIG_RADIO_TYPHOON_PORT -1
49 #endif
50 
51 #ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ
52 #define CONFIG_RADIO_TYPHOON_MUTEFREQ 0
53 #endif
54 
55 static int io = CONFIG_RADIO_TYPHOON_PORT;
56 static int radio_nr = -1;
57 
58 module_param(io, int, 0);
59 MODULE_PARM_DESC(io, "I/O address of the Typhoon card (0x316 or 0x336)");
60 
61 module_param(radio_nr, int, 0);
62 
63 static unsigned long mutefreq = CONFIG_RADIO_TYPHOON_MUTEFREQ;
64 module_param(mutefreq, ulong, 0);
65 MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");
66 
67 #define RADIO_VERSION KERNEL_VERSION(0, 1, 1)
68 
69 #define BANNER "Typhoon Radio Card driver v0.1.1\n"
70 
71 struct typhoon {
72 	struct v4l2_device v4l2_dev;
73 	struct video_device vdev;
74 	int io;
75 	int curvol;
76 	int muted;
77 	unsigned long curfreq;
78 	unsigned long mutefreq;
79 	struct mutex lock;
80 };
81 
82 static struct typhoon typhoon_card;
83 
84 static void typhoon_setvol_generic(struct typhoon *dev, int vol)
85 {
86 	mutex_lock(&dev->lock);
87 	vol >>= 14;				/* Map 16 bit to 2 bit */
88 	vol &= 3;
89 	outb_p(vol / 2, dev->io);		/* Set the volume, high bit. */
90 	outb_p(vol % 2, dev->io + 2);	/* Set the volume, low bit. */
91 	mutex_unlock(&dev->lock);
92 }
93 
94 static int typhoon_setfreq_generic(struct typhoon *dev,
95 				   unsigned long frequency)
96 {
97 	unsigned long outval;
98 	unsigned long x;
99 
100 	/*
101 	 * The frequency transfer curve is not linear. The best fit I could
102 	 * get is
103 	 *
104 	 * outval = -155 + exp((f + 15.55) * 0.057))
105 	 *
106 	 * where frequency f is in MHz. Since we don't have exp in the kernel,
107 	 * I approximate this function by a third order polynomial.
108 	 *
109 	 */
110 
111 	mutex_lock(&dev->lock);
112 	x = frequency / 160;
113 	outval = (x * x + 2500) / 5000;
114 	outval = (outval * x + 5000) / 10000;
115 	outval -= (10 * x * x + 10433) / 20866;
116 	outval += 4 * x - 11505;
117 
118 	outb_p((outval >> 8) & 0x01, dev->io + 4);
119 	outb_p(outval >> 9, dev->io + 6);
120 	outb_p(outval & 0xff, dev->io + 8);
121 	mutex_unlock(&dev->lock);
122 
123 	return 0;
124 }
125 
126 static int typhoon_setfreq(struct typhoon *dev, unsigned long frequency)
127 {
128 	typhoon_setfreq_generic(dev, frequency);
129 	dev->curfreq = frequency;
130 	return 0;
131 }
132 
133 static void typhoon_mute(struct typhoon *dev)
134 {
135 	if (dev->muted == 1)
136 		return;
137 	typhoon_setvol_generic(dev, 0);
138 	typhoon_setfreq_generic(dev, dev->mutefreq);
139 	dev->muted = 1;
140 }
141 
142 static void typhoon_unmute(struct typhoon *dev)
143 {
144 	if (dev->muted == 0)
145 		return;
146 	typhoon_setfreq_generic(dev, dev->curfreq);
147 	typhoon_setvol_generic(dev, dev->curvol);
148 	dev->muted = 0;
149 }
150 
151 static int typhoon_setvol(struct typhoon *dev, int vol)
152 {
153 	if (dev->muted && vol != 0) {	/* user is unmuting the card */
154 		dev->curvol = vol;
155 		typhoon_unmute(dev);
156 		return 0;
157 	}
158 	if (vol == dev->curvol)		/* requested volume == current */
159 		return 0;
160 
161 	if (vol == 0) {			/* volume == 0 means mute the card */
162 		typhoon_mute(dev);
163 		dev->curvol = vol;
164 		return 0;
165 	}
166 	typhoon_setvol_generic(dev, vol);
167 	dev->curvol = vol;
168 	return 0;
169 }
170 
171 static int vidioc_querycap(struct file *file, void  *priv,
172 					struct v4l2_capability *v)
173 {
174 	strlcpy(v->driver, "radio-typhoon", sizeof(v->driver));
175 	strlcpy(v->card, "Typhoon Radio", sizeof(v->card));
176 	strlcpy(v->bus_info, "ISA", sizeof(v->bus_info));
177 	v->version = RADIO_VERSION;
178 	v->capabilities = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
179 	return 0;
180 }
181 
182 static int vidioc_g_tuner(struct file *file, void *priv,
183 					struct v4l2_tuner *v)
184 {
185 	if (v->index > 0)
186 		return -EINVAL;
187 
188 	strlcpy(v->name, "FM", sizeof(v->name));
189 	v->type = V4L2_TUNER_RADIO;
190 	v->rangelow = 87.5 * 16000;
191 	v->rangehigh = 108 * 16000;
192 	v->rxsubchans = V4L2_TUNER_SUB_MONO;
193 	v->capability = V4L2_TUNER_CAP_LOW;
194 	v->audmode = V4L2_TUNER_MODE_MONO;
195 	v->signal = 0xFFFF;     /* We can't get the signal strength */
196 	return 0;
197 }
198 
199 static int vidioc_s_tuner(struct file *file, void *priv,
200 					struct v4l2_tuner *v)
201 {
202 	return v->index ? -EINVAL : 0;
203 }
204 
205 static int vidioc_g_frequency(struct file *file, void *priv,
206 					struct v4l2_frequency *f)
207 {
208 	struct typhoon *dev = video_drvdata(file);
209 
210 	f->type = V4L2_TUNER_RADIO;
211 	f->frequency = dev->curfreq;
212 	return 0;
213 }
214 
215 static int vidioc_s_frequency(struct file *file, void *priv,
216 					struct v4l2_frequency *f)
217 {
218 	struct typhoon *dev = video_drvdata(file);
219 
220 	dev->curfreq = f->frequency;
221 	typhoon_setfreq(dev, dev->curfreq);
222 	return 0;
223 }
224 
225 static int vidioc_queryctrl(struct file *file, void *priv,
226 					struct v4l2_queryctrl *qc)
227 {
228 	switch (qc->id) {
229 	case V4L2_CID_AUDIO_MUTE:
230 		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 1);
231 	case V4L2_CID_AUDIO_VOLUME:
232 		return v4l2_ctrl_query_fill(qc, 0, 65535, 16384, 65535);
233 	}
234 	return -EINVAL;
235 }
236 
237 static int vidioc_g_ctrl(struct file *file, void *priv,
238 					struct v4l2_control *ctrl)
239 {
240 	struct typhoon *dev = video_drvdata(file);
241 
242 	switch (ctrl->id) {
243 	case V4L2_CID_AUDIO_MUTE:
244 		ctrl->value = dev->muted;
245 		return 0;
246 	case V4L2_CID_AUDIO_VOLUME:
247 		ctrl->value = dev->curvol;
248 		return 0;
249 	}
250 	return -EINVAL;
251 }
252 
253 static int vidioc_s_ctrl (struct file *file, void *priv,
254 					struct v4l2_control *ctrl)
255 {
256 	struct typhoon *dev = video_drvdata(file);
257 
258 	switch (ctrl->id) {
259 	case V4L2_CID_AUDIO_MUTE:
260 		if (ctrl->value)
261 			typhoon_mute(dev);
262 		else
263 			typhoon_unmute(dev);
264 		return 0;
265 	case V4L2_CID_AUDIO_VOLUME:
266 		typhoon_setvol(dev, ctrl->value);
267 		return 0;
268 	}
269 	return -EINVAL;
270 }
271 
272 static int vidioc_g_input(struct file *filp, void *priv, unsigned int *i)
273 {
274 	*i = 0;
275 	return 0;
276 }
277 
278 static int vidioc_s_input(struct file *filp, void *priv, unsigned int i)
279 {
280 	return i ? -EINVAL : 0;
281 }
282 
283 static int vidioc_g_audio(struct file *file, void *priv,
284 					struct v4l2_audio *a)
285 {
286 	a->index = 0;
287 	strlcpy(a->name, "Radio", sizeof(a->name));
288 	a->capability = V4L2_AUDCAP_STEREO;
289 	return 0;
290 }
291 
292 static int vidioc_s_audio(struct file *file, void *priv,
293 					struct v4l2_audio *a)
294 {
295 	return a->index ? -EINVAL : 0;
296 }
297 
298 static int vidioc_log_status(struct file *file, void *priv)
299 {
300 	struct typhoon *dev = video_drvdata(file);
301 	struct v4l2_device *v4l2_dev = &dev->v4l2_dev;
302 
303 	v4l2_info(v4l2_dev, BANNER);
304 #ifdef MODULE
305 	v4l2_info(v4l2_dev, "Load type: Driver loaded as a module\n\n");
306 #else
307 	v4l2_info(v4l2_dev, "Load type: Driver compiled into kernel\n\n");
308 #endif
309 	v4l2_info(v4l2_dev, "frequency = %lu kHz\n", dev->curfreq >> 4);
310 	v4l2_info(v4l2_dev, "volume = %d\n", dev->curvol);
311 	v4l2_info(v4l2_dev, "mute = %s\n", dev->muted ?  "on" : "off");
312 	v4l2_info(v4l2_dev, "io = 0x%x\n", dev->io);
313 	v4l2_info(v4l2_dev, "mute frequency = %lu kHz\n", dev->mutefreq >> 4);
314 	return 0;
315 }
316 
317 static int typhoon_open(struct file *file)
318 {
319 	return 0;
320 }
321 
322 static int typhoon_release(struct file *file)
323 {
324 	return 0;
325 }
326 
327 static const struct v4l2_file_operations typhoon_fops = {
328 	.owner		= THIS_MODULE,
329 	.open           = typhoon_open,
330 	.release        = typhoon_release,
331 	.ioctl		= video_ioctl2,
332 };
333 
334 static const struct v4l2_ioctl_ops typhoon_ioctl_ops = {
335 	.vidioc_log_status  = vidioc_log_status,
336 	.vidioc_querycap    = vidioc_querycap,
337 	.vidioc_g_tuner     = vidioc_g_tuner,
338 	.vidioc_s_tuner     = vidioc_s_tuner,
339 	.vidioc_g_audio     = vidioc_g_audio,
340 	.vidioc_s_audio     = vidioc_s_audio,
341 	.vidioc_g_input     = vidioc_g_input,
342 	.vidioc_s_input     = vidioc_s_input,
343 	.vidioc_g_frequency = vidioc_g_frequency,
344 	.vidioc_s_frequency = vidioc_s_frequency,
345 	.vidioc_queryctrl   = vidioc_queryctrl,
346 	.vidioc_g_ctrl      = vidioc_g_ctrl,
347 	.vidioc_s_ctrl      = vidioc_s_ctrl,
348 };
349 
350 static int __init typhoon_init(void)
351 {
352 	struct typhoon *dev = &typhoon_card;
353 	struct v4l2_device *v4l2_dev = &dev->v4l2_dev;
354 	int res;
355 
356 	strlcpy(v4l2_dev->name, "typhoon", sizeof(v4l2_dev->name));
357 	dev->io = io;
358 	dev->curfreq = dev->mutefreq = mutefreq;
359 
360 	if (dev->io == -1) {
361 		v4l2_err(v4l2_dev, "You must set an I/O address with io=0x316 or io=0x336\n");
362 		return -EINVAL;
363 	}
364 
365 	if (dev->mutefreq < 87000 || dev->mutefreq > 108500) {
366 		v4l2_err(v4l2_dev, "You must set a frequency (in kHz) used when muting the card,\n");
367 		v4l2_err(v4l2_dev, "e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108500)\n");
368 		return -EINVAL;
369 	}
370 
371 	mutex_init(&dev->lock);
372 	if (!request_region(dev->io, 8, "typhoon")) {
373 		v4l2_err(v4l2_dev, "port 0x%x already in use\n",
374 		       dev->io);
375 		return -EBUSY;
376 	}
377 
378 	res = v4l2_device_register(NULL, v4l2_dev);
379 	if (res < 0) {
380 		release_region(dev->io, 8);
381 		v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
382 		return res;
383 	}
384 	v4l2_info(v4l2_dev, BANNER);
385 
386 	strlcpy(dev->vdev.name, v4l2_dev->name, sizeof(dev->vdev.name));
387 	dev->vdev.v4l2_dev = v4l2_dev;
388 	dev->vdev.fops = &typhoon_fops;
389 	dev->vdev.ioctl_ops = &typhoon_ioctl_ops;
390 	dev->vdev.release = video_device_release_empty;
391 	video_set_drvdata(&dev->vdev, dev);
392 	if (video_register_device(&dev->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
393 		v4l2_device_unregister(&dev->v4l2_dev);
394 		release_region(dev->io, 8);
395 		return -EINVAL;
396 	}
397 	v4l2_info(v4l2_dev, "port 0x%x.\n", dev->io);
398 	v4l2_info(v4l2_dev, "mute frequency is %lu kHz.\n", dev->mutefreq);
399 	dev->mutefreq <<= 4;
400 
401 	/* mute card - prevents noisy bootups */
402 	typhoon_mute(dev);
403 
404 	return 0;
405 }
406 
407 static void __exit typhoon_exit(void)
408 {
409 	struct typhoon *dev = &typhoon_card;
410 
411 	video_unregister_device(&dev->vdev);
412 	v4l2_device_unregister(&dev->v4l2_dev);
413 	release_region(dev->io, 8);
414 }
415 
416 module_init(typhoon_init);
417 module_exit(typhoon_exit);
418 
419