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
42static int io = CONFIG_RADIO_AZTECH_PORT;
43static int radio_nr = -1;
44static int radio_wait_time = 1000;
45static int users = 0;
46static struct semaphore lock;
47
48struct az_device
49{
50	int curvol;
51	unsigned long curfreq;
52	int stereo;
53};
54
55static int volconvert(int level)
56{
57	level>>=14;	 	/* Map 16bits down to 2 bit */
58 	level&=3;
59
60	/* convert to card-friendly values */
61	switch (level)
62	{
63		case 0:
64			return 0;
65		case 1:
66			return 1;
67		case 2:
68			return 4;
69		case 3:
70			return 5;
71	}
72	return 0;	/* Quieten gcc */
73}
74
75static void send_0_byte (struct az_device *dev)
76{
77	udelay(radio_wait_time);
78	outb_p(2+volconvert(dev->curvol), io);
79	outb_p(64+2+volconvert(dev->curvol), io);
80}
81
82static void send_1_byte (struct az_device *dev)
83{
84	udelay (radio_wait_time);
85	outb_p(128+2+volconvert(dev->curvol), io);
86	outb_p(128+64+2+volconvert(dev->curvol), io);
87}
88
89static int az_setvol(struct az_device *dev, int vol)
90{
91	down(&lock);
92	outb (volconvert(vol), io);
93	up(&lock);
94	return 0;
95}
96
97/* thanks to Michael Dwyer for giving me a dose of clues in
98 * the signal strength department..
99 *
100 * This card has a stereo bit - bit 0 set = mono, not set = stereo
101 * It also has a "signal" bit - bit 1 set = bad signal, not set = good
102 *
103 */
104
105static int az_getsigstr(struct az_device *dev)
106{
107	if (inb(io) & 2)	/* bit set = no signal present */
108		return 0;
109	return 1;		/* signal present */
110}
111
112static int az_getstereo(struct az_device *dev)
113{
114	if (inb(io) & 1) 	/* bit set = mono */
115		return 0;
116	return 1;		/* stereo */
117}
118
119static int az_setfreq(struct az_device *dev, unsigned long frequency)
120{
121	int  i;
122
123	frequency += 171200;		/* Add 10.7 MHz IF		*/
124	frequency /= 800;		/* Convert to 50 kHz units	*/
125
126	down(&lock);
127
128	send_0_byte (dev);		/*  0: LSB of frequency       */
129
130	for (i = 0; i < 13; i++)	/*   : frequency bits (1-13)  */
131		if (frequency & (1 << i))
132			send_1_byte (dev);
133		else
134			send_0_byte (dev);
135
136	send_0_byte (dev);		/* 14: test bit - always 0    */
137	send_0_byte (dev);		/* 15: test bit - always 0    */
138	send_0_byte (dev);		/* 16: band data 0 - always 0 */
139	if (dev->stereo)		/* 17: stereo (1 to enable)   */
140		send_1_byte (dev);
141	else
142		send_0_byte (dev);
143
144	send_1_byte (dev);		/* 18: band data 1 - unknown  */
145	send_0_byte (dev);		/* 19: time base - always 0   */
146	send_0_byte (dev);		/* 20: spacing (0 = 25 kHz)   */
147	send_1_byte (dev);		/* 21: spacing (1 = 25 kHz)   */
148	send_0_byte (dev);		/* 22: spacing (0 = 25 kHz)   */
149	send_1_byte (dev);		/* 23: AM/FM (FM = 1, always) */
150
151	/* latch frequency */
152
153	udelay (radio_wait_time);
154	outb_p(128+64+volconvert(dev->curvol), io);
155
156	up(&lock);
157
158	return 0;
159}
160
161static int az_ioctl(struct video_device *dev, unsigned int cmd, void *arg)
162{
163	struct az_device *az=dev->priv;
164
165	switch(cmd)
166	{
167		case VIDIOCGCAP:
168		{
169			struct video_capability v;
170			v.type=VID_TYPE_TUNER;
171			v.channels=1;
172			v.audios=1;
173			/* No we don't do pictures */
174			v.maxwidth=0;
175			v.maxheight=0;
176			v.minwidth=0;
177			v.minheight=0;
178			strcpy(v.name, "Aztech Radio");
179			if(copy_to_user(arg,&v,sizeof(v)))
180				return -EFAULT;
181			return 0;
182		}
183		case VIDIOCGTUNER:
184		{
185			struct video_tuner v;
186			if(copy_from_user(&v, arg,sizeof(v))!=0)
187				return -EFAULT;
188			if(v.tuner)	/* Only 1 tuner */
189				return -EINVAL;
190			v.rangelow=(87*16000);
191			v.rangehigh=(108*16000);
192			v.flags=VIDEO_TUNER_LOW;
193			v.mode=VIDEO_MODE_AUTO;
194			v.signal=0xFFFF*az_getsigstr(az);
195			if(az_getstereo(az))
196				v.flags|=VIDEO_TUNER_STEREO_ON;
197			strcpy(v.name, "FM");
198			if(copy_to_user(arg,&v, sizeof(v)))
199				return -EFAULT;
200			return 0;
201		}
202		case VIDIOCSTUNER:
203		{
204			struct video_tuner v;
205			if(copy_from_user(&v, arg, sizeof(v)))
206				return -EFAULT;
207			if(v.tuner!=0)
208				return -EINVAL;
209			/* Only 1 tuner so no setting needed ! */
210			return 0;
211		}
212		case VIDIOCGFREQ:
213			if(copy_to_user(arg, &az->curfreq, sizeof(az->curfreq)))
214				return -EFAULT;
215			return 0;
216		case VIDIOCSFREQ:
217			if(copy_from_user(&az->curfreq, arg,sizeof(az->curfreq)))
218				return -EFAULT;
219			az_setfreq(az, az->curfreq);
220			return 0;
221		case VIDIOCGAUDIO:
222		{
223			struct video_audio v;
224			memset(&v,0, sizeof(v));
225			v.flags|=VIDEO_AUDIO_MUTABLE|VIDEO_AUDIO_VOLUME;
226			if(az->stereo)
227				v.mode=VIDEO_SOUND_STEREO;
228			else
229				v.mode=VIDEO_SOUND_MONO;
230			v.volume=az->curvol;
231			v.step=16384;
232			strcpy(v.name, "Radio");
233			if(copy_to_user(arg,&v, sizeof(v)))
234				return -EFAULT;
235			return 0;
236		}
237		case VIDIOCSAUDIO:
238		{
239			struct video_audio v;
240			if(copy_from_user(&v, arg, sizeof(v)))
241				return -EFAULT;
242			if(v.audio)
243				return -EINVAL;
244			az->curvol=v.volume;
245
246			az->stereo=(v.mode&VIDEO_SOUND_STEREO)?1:0;
247			if(v.flags&VIDEO_AUDIO_MUTE)
248				az_setvol(az,0);
249			else
250				az_setvol(az,az->curvol);
251			return 0;
252		}
253		default:
254			return -ENOIOCTLCMD;
255	}
256}
257
258static int az_open(struct video_device *dev, int flags)
259{
260	if(users)
261		return -EBUSY;
262	users++;
263	return 0;
264}
265
266static void az_close(struct video_device *dev)
267{
268	users--;
269}
270
271static struct az_device aztech_unit;
272
273static struct video_device aztech_radio=
274{
275	owner:		THIS_MODULE,
276	name:		"Aztech radio",
277	type:		VID_TYPE_TUNER,
278	hardware:	VID_HARDWARE_AZTECH,
279	open:		az_open,
280	close:		az_close,
281	ioctl:		az_ioctl,
282};
283
284static int __init aztech_init(void)
285{
286	if(io==-1)
287	{
288		printk(KERN_ERR "You must set an I/O address with io=0x???\n");
289		return -EINVAL;
290	}
291
292	if (!request_region(io, 2, "aztech"))
293	{
294		printk(KERN_ERR "aztech: port 0x%x already in use\n", io);
295		return -EBUSY;
296	}
297
298	init_MUTEX(&lock);
299	aztech_radio.priv=&aztech_unit;
300
301	if(video_register_device(&aztech_radio, VFL_TYPE_RADIO, radio_nr)==-1)
302	{
303		release_region(io,2);
304		return -EINVAL;
305	}
306
307	printk(KERN_INFO "Aztech radio card driver v1.00/19990224 rkroll@exploits.org\n");
308	/* mute card - prevents noisy bootups */
309	outb (0, io);
310	return 0;
311}
312
313MODULE_AUTHOR("Russell Kroll, Quay Lu, Donald Song, Jason Lewis, Scott McGrath, William McGrath");
314MODULE_DESCRIPTION("A driver for the Aztech radio card.");
315MODULE_LICENSE("GPL");
316
317MODULE_PARM(io, "i");
318MODULE_PARM(radio_nr, "i");
319MODULE_PARM_DESC(io, "I/O address of the Aztech card (0x350 or 0x358)");
320
321EXPORT_NO_SYMBOLS;
322
323static void __exit aztech_cleanup(void)
324{
325	video_unregister_device(&aztech_radio);
326	release_region(io,2);
327}
328
329module_init(aztech_init);
330module_exit(aztech_cleanup);
331