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
35MODULE_AUTHOR("R. Offermans & others");
36MODULE_DESCRIPTION("A driver for the TerraTec ActiveRadio Standalone radio card.");
37MODULE_LICENSE("GPL");
38MODULE_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. */
43static int io = 0x590;
44static int radio_nr = -1;
45
46module_param(radio_nr, int, 0444);
47MODULE_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
57static struct radio_isa_card *terratec_alloc(void)
58{
59 return kzalloc(size: sizeof(struct radio_isa_card), GFP_KERNEL);
60}
61
62static 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(value: 0x80, port: isa->io + 1);
72 else
73 outb(value: 0x00, port: 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
82static 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, port: isa->io);
110 outb(WRT_EN | DATA | CLK_ON, port: isa->io);
111 outb(WRT_EN | DATA, port: isa->io);
112 } else {
113 outb(WRT_EN | 0x00, port: isa->io);
114 outb(WRT_EN | 0x00 | CLK_ON, port: isa->io);
115 }
116 }
117 outb(value: 0x00, port: isa->io);
118 return 0;
119}
120
121static u32 terratec_g_signal(struct radio_isa_card *isa)
122{
123 /* bit set = no signal present */
124 return (inb(port: isa->io) & 2) ? 0 : 0xffff;
125}
126
127static 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
134static const int terratec_ioports[] = { 0x590 };
135
136static 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
156static int __init terratec_init(void)
157{
158 return isa_register_driver(&terratec_driver.driver, 1);
159}
160
161static void __exit terratec_exit(void)
162{
163 isa_unregister_driver(&terratec_driver.driver);
164}
165
166module_init(terratec_init);
167module_exit(terratec_exit);
168
169

source code of linux/drivers/media/radio/radio-terratec.c