xref: /openbmc/linux/drivers/media/radio/radio-gemtek.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /* GemTek radio card driver for Linux (C) 1998 Jonas Munsin <jmunsin@iki.fi>
2  *
3  * GemTek hasn't released any specs on the card, so the protocol had to
4  * be reverse engineered with dosemu.
5  *
6  * Besides the protocol changes, this is mostly a copy of:
7  *
8  *    RadioTrack II driver for Linux radio support (C) 1998 Ben Pfaff
9  *
10  *    Based on RadioTrack I/RadioReveal (C) 1997 M. Kirkwood
11  *    Converted to new API by Alan Cox <Alan.Cox@linux.org>
12  *    Various bugfixes and enhancements by Russell Kroll <rkroll@exploits.org>
13  *
14  * TODO: Allow for more than one of these foolish entities :-)
15  *
16  */
17 
18 #include <linux/module.h>	/* Modules 			*/
19 #include <linux/init.h>		/* Initdata			*/
20 #include <linux/ioport.h>	/* check_region, request_region	*/
21 #include <linux/delay.h>	/* udelay			*/
22 #include <asm/io.h>		/* outb, outb_p			*/
23 #include <asm/uaccess.h>	/* copy to/from user		*/
24 #include <linux/videodev.h>	/* kernel radio structs		*/
25 #include <linux/config.h>	/* CONFIG_RADIO_GEMTEK_PORT 	*/
26 #include <linux/spinlock.h>
27 
28 #ifndef CONFIG_RADIO_GEMTEK_PORT
29 #define CONFIG_RADIO_GEMTEK_PORT -1
30 #endif
31 
32 static int io = CONFIG_RADIO_GEMTEK_PORT;
33 static int radio_nr = -1;
34 static spinlock_t lock;
35 
36 struct gemtek_device
37 {
38 	int port;
39 	unsigned long curfreq;
40 	int muted;
41 };
42 
43 
44 /* local things */
45 
46 /* the correct way to mute the gemtek may be to write the last written
47  * frequency || 0x10, but just writing 0x10 once seems to do it as well
48  */
49 static void gemtek_mute(struct gemtek_device *dev)
50 {
51         if(dev->muted)
52 		return;
53 	spin_lock(&lock);
54 	outb(0x10, io);
55 	spin_unlock(&lock);
56 	dev->muted = 1;
57 }
58 
59 static void gemtek_unmute(struct gemtek_device *dev)
60 {
61 	if(dev->muted == 0)
62 		return;
63 	spin_lock(&lock);
64 	outb(0x20, io);
65 	spin_unlock(&lock);
66 	dev->muted = 0;
67 }
68 
69 static void zero(void)
70 {
71 	outb_p(0x04, io);
72 	udelay(5);
73 	outb_p(0x05, io);
74 	udelay(5);
75 }
76 
77 static void one(void)
78 {
79 	outb_p(0x06, io);
80 	udelay(5);
81 	outb_p(0x07, io);
82 	udelay(5);
83 }
84 
85 static int gemtek_setfreq(struct gemtek_device *dev, unsigned long freq)
86 {
87 	int i;
88 
89 /*        freq = 78.25*((float)freq/16000.0 + 10.52); */
90 
91 	freq /= 16;
92 	freq += 10520;
93 	freq *= 7825;
94 	freq /= 100000;
95 
96 	spin_lock(&lock);
97 
98 	/* 2 start bits */
99 	outb_p(0x03, io);
100 	udelay(5);
101 	outb_p(0x07, io);
102 	udelay(5);
103 
104         /* 28 frequency bits (lsb first) */
105 	for (i = 0; i < 14; i++)
106 		if (freq & (1 << i))
107 			one();
108 		else
109 			zero();
110         /* 36 unknown bits */
111 	for (i = 0; i < 11; i++)
112 		zero();
113 	one();
114 	for (i = 0; i < 4; i++)
115 		zero();
116 	one();
117 	zero();
118 
119 	/* 2 end bits */
120 	outb_p(0x03, io);
121 	udelay(5);
122 	outb_p(0x07, io);
123 	udelay(5);
124 
125 	spin_unlock(&lock);
126 
127 	return 0;
128 }
129 
130 static int gemtek_getsigstr(struct gemtek_device *dev)
131 {
132 	spin_lock(&lock);
133 	inb(io);
134 	udelay(5);
135 	spin_unlock(&lock);
136 	if (inb(io) & 8)		/* bit set = no signal present */
137 		return 0;
138 	return 1;		/* signal present */
139 }
140 
141 static int gemtek_do_ioctl(struct inode *inode, struct file *file,
142 			   unsigned int cmd, void *arg)
143 {
144 	struct video_device *dev = video_devdata(file);
145 	struct gemtek_device *rt=dev->priv;
146 
147 	switch(cmd)
148 	{
149 		case VIDIOCGCAP:
150 		{
151 			struct video_capability *v = arg;
152 			memset(v,0,sizeof(*v));
153 			v->type=VID_TYPE_TUNER;
154 			v->channels=1;
155 			v->audios=1;
156 			strcpy(v->name, "GemTek");
157 			return 0;
158 		}
159 		case VIDIOCGTUNER:
160 		{
161 			struct video_tuner *v = arg;
162 			if(v->tuner)	/* Only 1 tuner */
163 				return -EINVAL;
164 			v->rangelow=87*16000;
165 			v->rangehigh=108*16000;
166 			v->flags=VIDEO_TUNER_LOW;
167 			v->mode=VIDEO_MODE_AUTO;
168 			v->signal=0xFFFF*gemtek_getsigstr(rt);
169 			strcpy(v->name, "FM");
170 			return 0;
171 		}
172 		case VIDIOCSTUNER:
173 		{
174 			struct video_tuner *v = arg;
175 			if(v->tuner!=0)
176 				return -EINVAL;
177 			/* Only 1 tuner so no setting needed ! */
178 			return 0;
179 		}
180 		case VIDIOCGFREQ:
181 		{
182 			unsigned long *freq = arg;
183 			*freq = rt->curfreq;
184 			return 0;
185 		}
186 		case VIDIOCSFREQ:
187 		{
188 			unsigned long *freq = arg;
189 			rt->curfreq = *freq;
190 			/* needs to be called twice in order for getsigstr to work */
191 			gemtek_setfreq(rt, rt->curfreq);
192 			gemtek_setfreq(rt, rt->curfreq);
193 			return 0;
194 		}
195 		case VIDIOCGAUDIO:
196 		{
197 			struct video_audio *v = arg;
198 			memset(v,0, sizeof(*v));
199 			v->flags|=VIDEO_AUDIO_MUTABLE;
200 			v->volume=1;
201 			v->step=65535;
202 			strcpy(v->name, "Radio");
203 			return 0;
204 		}
205 		case VIDIOCSAUDIO:
206 		{
207 			struct video_audio *v = arg;
208 			if(v->audio)
209 				return -EINVAL;
210 
211 			if(v->flags&VIDEO_AUDIO_MUTE)
212 				gemtek_mute(rt);
213 			else
214 			        gemtek_unmute(rt);
215 
216 			return 0;
217 		}
218 		default:
219 			return -ENOIOCTLCMD;
220 	}
221 }
222 
223 static int gemtek_ioctl(struct inode *inode, struct file *file,
224 			unsigned int cmd, unsigned long arg)
225 {
226 	return video_usercopy(inode, file, cmd, arg, gemtek_do_ioctl);
227 }
228 
229 static struct gemtek_device gemtek_unit;
230 
231 static struct file_operations gemtek_fops = {
232 	.owner		= THIS_MODULE,
233 	.open           = video_exclusive_open,
234 	.release        = video_exclusive_release,
235 	.ioctl		= gemtek_ioctl,
236 	.llseek         = no_llseek,
237 };
238 
239 static struct video_device gemtek_radio=
240 {
241 	.owner		= THIS_MODULE,
242 	.name		= "GemTek radio",
243 	.type		= VID_TYPE_TUNER,
244 	.hardware	= VID_HARDWARE_GEMTEK,
245 	.fops           = &gemtek_fops,
246 };
247 
248 static int __init gemtek_init(void)
249 {
250 	if(io==-1)
251 	{
252 		printk(KERN_ERR "You must set an I/O address with io=0x20c, io=0x30c, io=0x24c or io=0x34c (io=0x020c or io=0x248 for the combined sound/radiocard)\n");
253 		return -EINVAL;
254 	}
255 
256 	if (!request_region(io, 4, "gemtek"))
257 	{
258 		printk(KERN_ERR "gemtek: port 0x%x already in use\n", io);
259 		return -EBUSY;
260 	}
261 
262 	gemtek_radio.priv=&gemtek_unit;
263 
264 	if(video_register_device(&gemtek_radio, VFL_TYPE_RADIO, radio_nr)==-1)
265 	{
266 		release_region(io, 4);
267 		return -EINVAL;
268 	}
269 	printk(KERN_INFO "GemTek Radio Card driver.\n");
270 
271 	spin_lock_init(&lock);
272 
273 	/* this is _maybe_ unnecessary */
274 	outb(0x01, io);
275 
276  	/* mute card - prevents noisy bootups */
277 	gemtek_unit.muted = 0;
278 	gemtek_mute(&gemtek_unit);
279 
280 	return 0;
281 }
282 
283 MODULE_AUTHOR("Jonas Munsin");
284 MODULE_DESCRIPTION("A driver for the GemTek Radio Card");
285 MODULE_LICENSE("GPL");
286 
287 module_param(io, int, 0);
288 MODULE_PARM_DESC(io, "I/O address of the GemTek card (0x20c, 0x30c, 0x24c or 0x34c (0x20c or 0x248 have been reported to work for the combined sound/radiocard)).");
289 module_param(radio_nr, int, 0);
290 
291 static void __exit gemtek_cleanup(void)
292 {
293 	video_unregister_device(&gemtek_radio);
294 	release_region(io,4);
295 }
296 
297 module_init(gemtek_init);
298 module_exit(gemtek_cleanup);
299 
300 /*
301   Local variables:
302   compile-command: "gcc -c -DMODVERSIONS -D__KERNEL__ -DMODULE -O6 -Wall -Wstrict-prototypes -I /home/blp/tmp/linux-2.1.111-rtrack/include radio-rtrack2.c"
303   End:
304 */
305