xref: /linux/drivers/media/radio/radio-terratec.c (revision 2455f0e124d317dd08d337a7550a78a224d4ba41)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Terratec ActiveRadio ISA Standalone card driver for Linux radio support
3  * (c) 1999 R. Offermanns (rolf@offermanns.de)
4  * based on the aimslab radio driver from M. Kirkwood
5  * many thanks to Michael Becker and Friedhelm Birth (from TerraTec)
6  *
7  *
8  * History:
9  * 1999-05-21	First preview release
10  *
11  *  Notes on the hardware:
12  *  There are two "main" chips on the card:
13  *  - Philips OM5610 (http://www-us.semiconductors.philips.com/acrobat/datasheets/OM5610_2.pdf)
14  *  - Philips SAA6588 (http://www-us.semiconductors.philips.com/acrobat/datasheets/SAA6588_1.pdf)
15  *  (you can get the datasheet at the above links)
16  *
17  *  Frequency control is done digitally -- ie out(port,encodefreq(95.8));
18  *  Volume Control is done digitally
19  *
20  * Converted to the radio-isa framework by Hans Verkuil <hans.verkuil@cisco.com>
21  * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@kernel.org>
22  */
23 
24 #include <linux/module.h>	/* Modules			*/
25 #include <linux/init.h>		/* Initdata			*/
26 #include <linux/ioport.h>	/* request_region		*/
27 #include <linux/videodev2.h>	/* kernel radio structs		*/
28 #include <linux/mutex.h>
29 #include <linux/io.h>		/* outb, outb_p			*/
30 #include <linux/slab.h>
31 #include <media/v4l2-device.h>
32 #include <media/v4l2-ioctl.h>
33 #include "radio-isa.h"
34 
35 MODULE_AUTHOR("R. Offermans & others");
36 MODULE_DESCRIPTION("A driver for the TerraTec ActiveRadio Standalone radio card.");
37 MODULE_LICENSE("GPL");
38 MODULE_VERSION("0.1.99");
39 
40 /* Note: there seems to be only one possible port (0x590), but without
41    hardware this is hard to verify. For now, this is the only one we will
42    support. */
43 static int io = 0x590;
44 static int radio_nr = -1;
45 
46 module_param(radio_nr, int, 0444);
47 MODULE_PARM_DESC(radio_nr, "Radio device number");
48 
49 #define WRT_DIS		0x00
50 #define CLK_OFF		0x00
51 #define IIC_DATA	0x01
52 #define IIC_CLK		0x02
53 #define DATA		0x04
54 #define CLK_ON		0x08
55 #define WRT_EN		0x10
56 
57 static struct radio_isa_card *terratec_alloc(void)
58 {
59 	return kzalloc(sizeof(struct radio_isa_card), GFP_KERNEL);
60 }
61 
62 static int terratec_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
63 {
64 	int i;
65 
66 	if (mute)
67 		vol = 0;
68 	vol = vol + (vol * 32); /* change both channels */
69 	for (i = 0; i < 8; i++) {
70 		if (vol & (0x80 >> i))
71 			outb(0x80, isa->io + 1);
72 		else
73 			outb(0x00, isa->io + 1);
74 	}
75 	return 0;
76 }
77 
78 
79 /* this is the worst part in this driver */
80 /* many more or less strange things are going on here, but hey, it works :) */
81 
82 static int terratec_s_frequency(struct radio_isa_card *isa, u32 freq)
83 {
84 	int i;
85 	int temp;
86 	long rest;
87 	unsigned char buffer[25];		/* we have to bit shift 25 registers */
88 
89 	freq = freq / 160;			/* convert the freq. to a nice to handle value */
90 	memset(buffer, 0, sizeof(buffer));
91 
92 	rest = freq * 10 + 10700;	/* I once had understood what is going on here */
93 					/* maybe some wise guy (friedhelm?) can comment this stuff */
94 	i = 13;
95 	temp = 102400;
96 	while (rest != 0) {
97 		if (rest % temp  == rest)
98 			buffer[i] = 0;
99 		else {
100 			buffer[i] = 1;
101 			rest = rest - temp;
102 		}
103 		i--;
104 		temp = temp / 2;
105 	}
106 
107 	for (i = 24; i > -1; i--) {	/* bit shift the values to the radiocard */
108 		if (buffer[i] == 1) {
109 			outb(WRT_EN | DATA, isa->io);
110 			outb(WRT_EN | DATA | CLK_ON, isa->io);
111 			outb(WRT_EN | DATA, isa->io);
112 		} else {
113 			outb(WRT_EN | 0x00, isa->io);
114 			outb(WRT_EN | 0x00 | CLK_ON, isa->io);
115 		}
116 	}
117 	outb(0x00, isa->io);
118 	return 0;
119 }
120 
121 static u32 terratec_g_signal(struct radio_isa_card *isa)
122 {
123 	/* bit set = no signal present	*/
124 	return (inb(isa->io) & 2) ? 0 : 0xffff;
125 }
126 
127 static const struct radio_isa_ops terratec_ops = {
128 	.alloc = terratec_alloc,
129 	.s_mute_volume = terratec_s_mute_volume,
130 	.s_frequency = terratec_s_frequency,
131 	.g_signal = terratec_g_signal,
132 };
133 
134 static const int terratec_ioports[] = { 0x590 };
135 
136 static struct radio_isa_driver terratec_driver = {
137 	.driver = {
138 		.match		= radio_isa_match,
139 		.probe		= radio_isa_probe,
140 		.remove		= radio_isa_remove,
141 		.driver		= {
142 			.name	= "radio-terratec",
143 		},
144 	},
145 	.io_params = &io,
146 	.radio_nr_params = &radio_nr,
147 	.io_ports = terratec_ioports,
148 	.num_of_io_ports = ARRAY_SIZE(terratec_ioports),
149 	.region_size = 2,
150 	.card = "TerraTec ActiveRadio",
151 	.ops = &terratec_ops,
152 	.has_stereo = true,
153 	.max_volume = 10,
154 };
155 
156 static int __init terratec_init(void)
157 {
158 	return isa_register_driver(&terratec_driver.driver, 1);
159 }
160 
161 static void __exit terratec_exit(void)
162 {
163 	isa_unregister_driver(&terratec_driver.driver);
164 }
165 
166 module_init(terratec_init);
167 module_exit(terratec_exit);
168 
169