xref: /openbmc/linux/drivers/media/radio/radio-aztech.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /* radio-aztech.c - Aztech radio card driver for Linux 2.2
2  *
3  * Adapted to support the Video for Linux API by
4  * Russell Kroll <rkroll@exploits.org>.  Based on original tuner code by:
5  *
6  * Quay Ly
7  * Donald Song
8  * Jason Lewis      (jlewis@twilight.vtc.vsc.edu)
9  * Scott McGrath    (smcgrath@twilight.vtc.vsc.edu)
10  * William McGrath  (wmcgrath@twilight.vtc.vsc.edu)
11  *
12  * The basis for this code may be found at http://bigbang.vtc.vsc.edu/fmradio/
13  * along with more information on the card itself.
14  *
15  * History:
16  * 1999-02-24	Russell Kroll <rkroll@exploits.org>
17  *		Fine tuning/VIDEO_TUNER_LOW
18  * 		Range expanded to 87-108 MHz (from 87.9-107.8)
19  *
20  * Notable changes from the original source:
21  * - includes stripped down to the essentials
22  * - for loops used as delays replaced with udelay()
23  * - #defines removed, changed to static values
24  * - tuning structure changed - no more character arrays, other changes
25 */
26 
27 #include <linux/module.h>	/* Modules 			*/
28 #include <linux/init.h>		/* Initdata			*/
29 #include <linux/ioport.h>	/* check_region, request_region	*/
30 #include <linux/delay.h>	/* udelay			*/
31 #include <asm/io.h>		/* outb, outb_p			*/
32 #include <asm/uaccess.h>	/* copy to/from user		*/
33 #include <linux/videodev.h>	/* kernel radio structs		*/
34 #include <linux/config.h>	/* CONFIG_RADIO_AZTECH_PORT 	*/
35 
36 /* acceptable ports: 0x350 (JP3 shorted), 0x358 (JP3 open) */
37 
38 #ifndef CONFIG_RADIO_AZTECH_PORT
39 #define CONFIG_RADIO_AZTECH_PORT -1
40 #endif
41 
42 static int io = CONFIG_RADIO_AZTECH_PORT;
43 static int radio_nr = -1;
44 static int radio_wait_time = 1000;
45 static struct semaphore lock;
46 
47 struct az_device
48 {
49 	int curvol;
50 	unsigned long curfreq;
51 	int stereo;
52 };
53 
54 static int volconvert(int level)
55 {
56 	level>>=14;	 	/* Map 16bits down to 2 bit */
57  	level&=3;
58 
59 	/* convert to card-friendly values */
60 	switch (level)
61 	{
62 		case 0:
63 			return 0;
64 		case 1:
65 			return 1;
66 		case 2:
67 			return 4;
68 		case 3:
69 			return 5;
70 	}
71 	return 0;	/* Quieten gcc */
72 }
73 
74 static void send_0_byte (struct az_device *dev)
75 {
76 	udelay(radio_wait_time);
77 	outb_p(2+volconvert(dev->curvol), io);
78 	outb_p(64+2+volconvert(dev->curvol), io);
79 }
80 
81 static void send_1_byte (struct az_device *dev)
82 {
83 	udelay (radio_wait_time);
84 	outb_p(128+2+volconvert(dev->curvol), io);
85 	outb_p(128+64+2+volconvert(dev->curvol), io);
86 }
87 
88 static int az_setvol(struct az_device *dev, int vol)
89 {
90 	down(&lock);
91 	outb (volconvert(vol), io);
92 	up(&lock);
93 	return 0;
94 }
95 
96 /* thanks to Michael Dwyer for giving me a dose of clues in
97  * the signal strength department..
98  *
99  * This card has a stereo bit - bit 0 set = mono, not set = stereo
100  * It also has a "signal" bit - bit 1 set = bad signal, not set = good
101  *
102  */
103 
104 static int az_getsigstr(struct az_device *dev)
105 {
106 	if (inb(io) & 2)	/* bit set = no signal present */
107 		return 0;
108 	return 1;		/* signal present */
109 }
110 
111 static int az_getstereo(struct az_device *dev)
112 {
113 	if (inb(io) & 1) 	/* bit set = mono */
114 		return 0;
115 	return 1;		/* stereo */
116 }
117 
118 static int az_setfreq(struct az_device *dev, unsigned long frequency)
119 {
120 	int  i;
121 
122 	frequency += 171200;		/* Add 10.7 MHz IF		*/
123 	frequency /= 800;		/* Convert to 50 kHz units	*/
124 
125 	down(&lock);
126 
127 	send_0_byte (dev);		/*  0: LSB of frequency       */
128 
129 	for (i = 0; i < 13; i++)	/*   : frequency bits (1-13)  */
130 		if (frequency & (1 << i))
131 			send_1_byte (dev);
132 		else
133 			send_0_byte (dev);
134 
135 	send_0_byte (dev);		/* 14: test bit - always 0    */
136 	send_0_byte (dev);		/* 15: test bit - always 0    */
137 	send_0_byte (dev);		/* 16: band data 0 - always 0 */
138 	if (dev->stereo)		/* 17: stereo (1 to enable)   */
139 		send_1_byte (dev);
140 	else
141 		send_0_byte (dev);
142 
143 	send_1_byte (dev);		/* 18: band data 1 - unknown  */
144 	send_0_byte (dev);		/* 19: time base - always 0   */
145 	send_0_byte (dev);		/* 20: spacing (0 = 25 kHz)   */
146 	send_1_byte (dev);		/* 21: spacing (1 = 25 kHz)   */
147 	send_0_byte (dev);		/* 22: spacing (0 = 25 kHz)   */
148 	send_1_byte (dev);		/* 23: AM/FM (FM = 1, always) */
149 
150 	/* latch frequency */
151 
152 	udelay (radio_wait_time);
153 	outb_p(128+64+volconvert(dev->curvol), io);
154 
155 	up(&lock);
156 
157 	return 0;
158 }
159 
160 static int az_do_ioctl(struct inode *inode, struct file *file,
161 		       unsigned int cmd, void *arg)
162 {
163 	struct video_device *dev = video_devdata(file);
164 	struct az_device *az = dev->priv;
165 
166 	switch(cmd)
167 	{
168 		case VIDIOCGCAP:
169 		{
170 			struct video_capability *v = arg;
171 			memset(v,0,sizeof(*v));
172 			v->type=VID_TYPE_TUNER;
173 			v->channels=1;
174 			v->audios=1;
175 			strcpy(v->name, "Aztech Radio");
176 			return 0;
177 		}
178 		case VIDIOCGTUNER:
179 		{
180 			struct video_tuner *v = arg;
181 			if(v->tuner)	/* Only 1 tuner */
182 				return -EINVAL;
183 			v->rangelow=(87*16000);
184 			v->rangehigh=(108*16000);
185 			v->flags=VIDEO_TUNER_LOW;
186 			v->mode=VIDEO_MODE_AUTO;
187 			v->signal=0xFFFF*az_getsigstr(az);
188 			if(az_getstereo(az))
189 				v->flags|=VIDEO_TUNER_STEREO_ON;
190 			strcpy(v->name, "FM");
191 			return 0;
192 		}
193 		case VIDIOCSTUNER:
194 		{
195 			struct video_tuner *v = arg;
196 			if(v->tuner!=0)
197 				return -EINVAL;
198 			return 0;
199 		}
200 		case VIDIOCGFREQ:
201 		{
202 			unsigned long *freq = arg;
203 			*freq = az->curfreq;
204 			return 0;
205 		}
206 		case VIDIOCSFREQ:
207 		{
208 			unsigned long *freq = arg;
209 			az->curfreq = *freq;
210 			az_setfreq(az, az->curfreq);
211 			return 0;
212 		}
213 		case VIDIOCGAUDIO:
214 		{
215 			struct video_audio *v = arg;
216 			memset(v,0, sizeof(*v));
217 			v->flags|=VIDEO_AUDIO_MUTABLE|VIDEO_AUDIO_VOLUME;
218 			if(az->stereo)
219 				v->mode=VIDEO_SOUND_STEREO;
220 			else
221 				v->mode=VIDEO_SOUND_MONO;
222 			v->volume=az->curvol;
223 			v->step=16384;
224 			strcpy(v->name, "Radio");
225 			return 0;
226 		}
227 		case VIDIOCSAUDIO:
228 		{
229 			struct video_audio *v = arg;
230 			if(v->audio)
231 				return -EINVAL;
232 			az->curvol=v->volume;
233 
234 			az->stereo=(v->mode&VIDEO_SOUND_STEREO)?1:0;
235 			if(v->flags&VIDEO_AUDIO_MUTE)
236 				az_setvol(az,0);
237 			else
238 				az_setvol(az,az->curvol);
239 			return 0;
240 		}
241 		default:
242 			return -ENOIOCTLCMD;
243 	}
244 }
245 
246 static int az_ioctl(struct inode *inode, struct file *file,
247 		    unsigned int cmd, unsigned long arg)
248 {
249 	return video_usercopy(inode, file, cmd, arg, az_do_ioctl);
250 }
251 
252 static struct az_device aztech_unit;
253 
254 static struct file_operations aztech_fops = {
255 	.owner		= THIS_MODULE,
256 	.open           = video_exclusive_open,
257 	.release        = video_exclusive_release,
258 	.ioctl		= az_ioctl,
259 	.llseek         = no_llseek,
260 };
261 
262 static struct video_device aztech_radio=
263 {
264 	.owner		= THIS_MODULE,
265 	.name		= "Aztech radio",
266 	.type		= VID_TYPE_TUNER,
267 	.hardware	= VID_HARDWARE_AZTECH,
268 	.fops           = &aztech_fops,
269 };
270 
271 static int __init aztech_init(void)
272 {
273 	if(io==-1)
274 	{
275 		printk(KERN_ERR "You must set an I/O address with io=0x???\n");
276 		return -EINVAL;
277 	}
278 
279 	if (!request_region(io, 2, "aztech"))
280 	{
281 		printk(KERN_ERR "aztech: port 0x%x already in use\n", io);
282 		return -EBUSY;
283 	}
284 
285 	init_MUTEX(&lock);
286 	aztech_radio.priv=&aztech_unit;
287 
288 	if(video_register_device(&aztech_radio, VFL_TYPE_RADIO, radio_nr)==-1)
289 	{
290 		release_region(io,2);
291 		return -EINVAL;
292 	}
293 
294 	printk(KERN_INFO "Aztech radio card driver v1.00/19990224 rkroll@exploits.org\n");
295 	/* mute card - prevents noisy bootups */
296 	outb (0, io);
297 	return 0;
298 }
299 
300 MODULE_AUTHOR("Russell Kroll, Quay Lu, Donald Song, Jason Lewis, Scott McGrath, William McGrath");
301 MODULE_DESCRIPTION("A driver for the Aztech radio card.");
302 MODULE_LICENSE("GPL");
303 
304 module_param(io, int, 0);
305 module_param(radio_nr, int, 0);
306 MODULE_PARM_DESC(io, "I/O address of the Aztech card (0x350 or 0x358)");
307 
308 static void __exit aztech_cleanup(void)
309 {
310 	video_unregister_device(&aztech_radio);
311 	release_region(io,2);
312 }
313 
314 module_init(aztech_init);
315 module_exit(aztech_cleanup);
316