radio-terratec.c

  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 <hverkuil@kernel.org>
 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(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(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
 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, 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
121static 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
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