xref: /linux/drivers/media/radio/radio-typhoon.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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 
32 #include <linux/module.h>	/* Modules                        */
33 #include <linux/init.h>		/* Initdata                       */
34 #include <linux/ioport.h>	/* request_region		  */
35 #include <linux/proc_fs.h>	/* radio card status report	  */
36 #include <asm/io.h>		/* outb, outb_p                   */
37 #include <asm/uaccess.h>	/* copy to/from user              */
38 #include <linux/videodev.h>	/* kernel radio structs           */
39 #include <media/v4l2-common.h>
40 #include <linux/config.h>	/* CONFIG_RADIO_TYPHOON_*         */
41 
42 #define BANNER "Typhoon Radio Card driver v0.1\n"
43 
44 #ifndef CONFIG_RADIO_TYPHOON_PORT
45 #define CONFIG_RADIO_TYPHOON_PORT -1
46 #endif
47 
48 #ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ
49 #define CONFIG_RADIO_TYPHOON_MUTEFREQ 0
50 #endif
51 
52 #ifndef CONFIG_PROC_FS
53 #undef CONFIG_RADIO_TYPHOON_PROC_FS
54 #endif
55 
56 struct typhoon_device {
57 	int users;
58 	int iobase;
59 	int curvol;
60 	int muted;
61 	unsigned long curfreq;
62 	unsigned long mutefreq;
63 	struct mutex lock;
64 };
65 
66 static void typhoon_setvol_generic(struct typhoon_device *dev, int vol);
67 static int typhoon_setfreq_generic(struct typhoon_device *dev,
68 				   unsigned long frequency);
69 static int typhoon_setfreq(struct typhoon_device *dev, unsigned long frequency);
70 static void typhoon_mute(struct typhoon_device *dev);
71 static void typhoon_unmute(struct typhoon_device *dev);
72 static int typhoon_setvol(struct typhoon_device *dev, int vol);
73 static int typhoon_ioctl(struct inode *inode, struct file *file,
74 			 unsigned int cmd, unsigned long arg);
75 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
76 static int typhoon_get_info(char *buf, char **start, off_t offset, int len);
77 #endif
78 
79 static void typhoon_setvol_generic(struct typhoon_device *dev, int vol)
80 {
81 	mutex_lock(&dev->lock);
82 	vol >>= 14;				/* Map 16 bit to 2 bit */
83 	vol &= 3;
84 	outb_p(vol / 2, dev->iobase);		/* Set the volume, high bit. */
85 	outb_p(vol % 2, dev->iobase + 2);	/* Set the volume, low bit. */
86 	mutex_unlock(&dev->lock);
87 }
88 
89 static int typhoon_setfreq_generic(struct typhoon_device *dev,
90 				   unsigned long frequency)
91 {
92 	unsigned long outval;
93 	unsigned long x;
94 
95 	/*
96 	 * The frequency transfer curve is not linear. The best fit I could
97 	 * get is
98 	 *
99 	 * outval = -155 + exp((f + 15.55) * 0.057))
100 	 *
101 	 * where frequency f is in MHz. Since we don't have exp in the kernel,
102 	 * I approximate this function by a third order polynomial.
103 	 *
104 	 */
105 
106 	mutex_lock(&dev->lock);
107 	x = frequency / 160;
108 	outval = (x * x + 2500) / 5000;
109 	outval = (outval * x + 5000) / 10000;
110 	outval -= (10 * x * x + 10433) / 20866;
111 	outval += 4 * x - 11505;
112 
113 	outb_p((outval >> 8) & 0x01, dev->iobase + 4);
114 	outb_p(outval >> 9, dev->iobase + 6);
115 	outb_p(outval & 0xff, dev->iobase + 8);
116 	mutex_unlock(&dev->lock);
117 
118 	return 0;
119 }
120 
121 static int typhoon_setfreq(struct typhoon_device *dev, unsigned long frequency)
122 {
123 	typhoon_setfreq_generic(dev, frequency);
124 	dev->curfreq = frequency;
125 	return 0;
126 }
127 
128 static void typhoon_mute(struct typhoon_device *dev)
129 {
130 	if (dev->muted == 1)
131 		return;
132 	typhoon_setvol_generic(dev, 0);
133 	typhoon_setfreq_generic(dev, dev->mutefreq);
134 	dev->muted = 1;
135 }
136 
137 static void typhoon_unmute(struct typhoon_device *dev)
138 {
139 	if (dev->muted == 0)
140 		return;
141 	typhoon_setfreq_generic(dev, dev->curfreq);
142 	typhoon_setvol_generic(dev, dev->curvol);
143 	dev->muted = 0;
144 }
145 
146 static int typhoon_setvol(struct typhoon_device *dev, int vol)
147 {
148 	if (dev->muted && vol != 0) {	/* user is unmuting the card */
149 		dev->curvol = vol;
150 		typhoon_unmute(dev);
151 		return 0;
152 	}
153 	if (vol == dev->curvol)		/* requested volume == current */
154 		return 0;
155 
156 	if (vol == 0) {			/* volume == 0 means mute the card */
157 		typhoon_mute(dev);
158 		dev->curvol = vol;
159 		return 0;
160 	}
161 	typhoon_setvol_generic(dev, vol);
162 	dev->curvol = vol;
163 	return 0;
164 }
165 
166 
167 static int typhoon_do_ioctl(struct inode *inode, struct file *file,
168 			    unsigned int cmd, void *arg)
169 {
170 	struct video_device *dev = video_devdata(file);
171 	struct typhoon_device *typhoon = dev->priv;
172 
173 	switch (cmd) {
174 	case VIDIOCGCAP:
175 		{
176 			struct video_capability *v = arg;
177 			memset(v,0,sizeof(*v));
178 			v->type = VID_TYPE_TUNER;
179 			v->channels = 1;
180 			v->audios = 1;
181 			strcpy(v->name, "Typhoon Radio");
182 			return 0;
183 		}
184 	case VIDIOCGTUNER:
185 		{
186 			struct video_tuner *v = arg;
187 			if (v->tuner)	/* Only 1 tuner */
188 				return -EINVAL;
189 			v->rangelow = 875 * 1600;
190 			v->rangehigh = 1080 * 1600;
191 			v->flags = VIDEO_TUNER_LOW;
192 			v->mode = VIDEO_MODE_AUTO;
193 			v->signal = 0xFFFF;	/* We can't get the signal strength */
194 			strcpy(v->name, "FM");
195 			return 0;
196 		}
197 	case VIDIOCSTUNER:
198 		{
199 			struct video_tuner *v = arg;
200 			if (v->tuner != 0)
201 				return -EINVAL;
202 			/* Only 1 tuner so no setting needed ! */
203 			return 0;
204 		}
205 	case VIDIOCGFREQ:
206 	{
207 		unsigned long *freq = arg;
208 		*freq = typhoon->curfreq;
209 		return 0;
210 	}
211 	case VIDIOCSFREQ:
212 	{
213 		unsigned long *freq = arg;
214 		typhoon->curfreq = *freq;
215 		typhoon_setfreq(typhoon, typhoon->curfreq);
216 		return 0;
217 	}
218 	case VIDIOCGAUDIO:
219 		{
220 			struct video_audio *v = arg;
221 			memset(v, 0, sizeof(*v));
222 			v->flags |= VIDEO_AUDIO_MUTABLE | VIDEO_AUDIO_VOLUME;
223 			v->mode |= VIDEO_SOUND_MONO;
224 			v->volume = typhoon->curvol;
225 			v->step = 1 << 14;
226 			strcpy(v->name, "Typhoon Radio");
227 			return 0;
228 		}
229 	case VIDIOCSAUDIO:
230 		{
231 			struct video_audio *v = arg;
232 			if (v->audio)
233 				return -EINVAL;
234 			if (v->flags & VIDEO_AUDIO_MUTE)
235 				typhoon_mute(typhoon);
236 			else
237 				typhoon_unmute(typhoon);
238 			if (v->flags & VIDEO_AUDIO_VOLUME)
239 				typhoon_setvol(typhoon, v->volume);
240 			return 0;
241 		}
242 	default:
243 		return -ENOIOCTLCMD;
244 	}
245 }
246 
247 static int typhoon_ioctl(struct inode *inode, struct file *file,
248 			 unsigned int cmd, unsigned long arg)
249 {
250 	return video_usercopy(inode, file, cmd, arg, typhoon_do_ioctl);
251 }
252 
253 static struct typhoon_device typhoon_unit =
254 {
255 	.iobase		= CONFIG_RADIO_TYPHOON_PORT,
256 	.curfreq	= CONFIG_RADIO_TYPHOON_MUTEFREQ,
257 	.mutefreq	= CONFIG_RADIO_TYPHOON_MUTEFREQ,
258 };
259 
260 static struct file_operations typhoon_fops = {
261 	.owner		= THIS_MODULE,
262 	.open           = video_exclusive_open,
263 	.release        = video_exclusive_release,
264 	.ioctl		= typhoon_ioctl,
265 	.compat_ioctl	= v4l_compat_ioctl32,
266 	.llseek         = no_llseek,
267 };
268 
269 static struct video_device typhoon_radio =
270 {
271 	.owner		= THIS_MODULE,
272 	.name		= "Typhoon Radio",
273 	.type		= VID_TYPE_TUNER,
274 	.hardware	= VID_HARDWARE_TYPHOON,
275 	.fops           = &typhoon_fops,
276 };
277 
278 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
279 
280 static int typhoon_get_info(char *buf, char **start, off_t offset, int len)
281 {
282 	char *out = buf;
283 
284 	#ifdef MODULE
285 	    #define MODULEPROCSTRING "Driver loaded as a module"
286 	#else
287 	    #define MODULEPROCSTRING "Driver compiled into kernel"
288 	#endif
289 
290 	/* output must be kept under PAGE_SIZE */
291 	out += sprintf(out, BANNER);
292 	out += sprintf(out, "Load type: " MODULEPROCSTRING "\n\n");
293 	out += sprintf(out, "frequency = %lu kHz\n",
294 		typhoon_unit.curfreq >> 4);
295 	out += sprintf(out, "volume = %d\n", typhoon_unit.curvol);
296 	out += sprintf(out, "mute = %s\n", typhoon_unit.muted ?
297 		"on" : "off");
298 	out += sprintf(out, "iobase = 0x%x\n", typhoon_unit.iobase);
299 	out += sprintf(out, "mute frequency = %lu kHz\n",
300 		typhoon_unit.mutefreq >> 4);
301 	return out - buf;
302 }
303 
304 #endif /* CONFIG_RADIO_TYPHOON_PROC_FS */
305 
306 MODULE_AUTHOR("Dr. Henrik Seidel");
307 MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");
308 MODULE_LICENSE("GPL");
309 
310 static int io = -1;
311 static int radio_nr = -1;
312 
313 module_param(io, int, 0);
314 MODULE_PARM_DESC(io, "I/O address of the Typhoon card (0x316 or 0x336)");
315 module_param(radio_nr, int, 0);
316 
317 #ifdef MODULE
318 static unsigned long mutefreq = 0;
319 module_param(mutefreq, ulong, 0);
320 MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");
321 #endif
322 
323 static int __init typhoon_init(void)
324 {
325 #ifdef MODULE
326 	if (io == -1) {
327 		printk(KERN_ERR "radio-typhoon: You must set an I/O address with io=0x316 or io=0x336\n");
328 		return -EINVAL;
329 	}
330 	typhoon_unit.iobase = io;
331 
332 	if (mutefreq < 87000 || mutefreq > 108500) {
333 		printk(KERN_ERR "radio-typhoon: You must set a frequency (in kHz) used when muting the card,\n");
334 		printk(KERN_ERR "radio-typhoon: e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108500)\n");
335 		return -EINVAL;
336 	}
337 	typhoon_unit.mutefreq = mutefreq;
338 #endif /* MODULE */
339 
340 	printk(KERN_INFO BANNER);
341 	mutex_init(&typhoon_unit.lock);
342 	io = typhoon_unit.iobase;
343 	if (!request_region(io, 8, "typhoon")) {
344 		printk(KERN_ERR "radio-typhoon: port 0x%x already in use\n",
345 		       typhoon_unit.iobase);
346 		return -EBUSY;
347 	}
348 
349 	typhoon_radio.priv = &typhoon_unit;
350 	if (video_register_device(&typhoon_radio, VFL_TYPE_RADIO, radio_nr) == -1)
351 	{
352 		release_region(io, 8);
353 		return -EINVAL;
354 	}
355 	printk(KERN_INFO "radio-typhoon: port 0x%x.\n", typhoon_unit.iobase);
356 	printk(KERN_INFO "radio-typhoon: mute frequency is %lu kHz.\n",
357 	       typhoon_unit.mutefreq);
358 	typhoon_unit.mutefreq <<= 4;
359 
360 	/* mute card - prevents noisy bootups */
361 	typhoon_mute(&typhoon_unit);
362 
363 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
364 	if (!create_proc_info_entry("driver/radio-typhoon", 0, NULL,
365 				    typhoon_get_info))
366 		printk(KERN_ERR "radio-typhoon: registering /proc/driver/radio-typhoon failed\n");
367 #endif
368 
369 	return 0;
370 }
371 
372 static void __exit typhoon_cleanup_module(void)
373 {
374 
375 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
376 	remove_proc_entry("driver/radio-typhoon", NULL);
377 #endif
378 
379 	video_unregister_device(&typhoon_radio);
380 	release_region(io, 8);
381 }
382 
383 module_init(typhoon_init);
384 module_exit(typhoon_cleanup_module);
385 
386