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