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1// SPDX-License-Identifier: GPL-2.0-only2/* Typhoon Radio Card driver for radio support3 * (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de>4 *5 * Notes on the hardware6 *7 * This card has two output sockets, one for speakers and one for line.8 * The speaker output has volume control, but only in four discrete9 * steps. The line output has neither volume control nor mute.10 *11 * The card has auto-stereo according to its manual, although it all12 * sounds mono to me (even with the Win/DOS drivers). Maybe it's my13 * antenna - I really don't know for sure.14 *15 * Frequency control is done digitally.16 *17 * Volume control is done digitally, but there are only four different18 * possible values. So you should better always turn the volume up and19 * use line control. I got the best results by connecting line output20 * to the sound card microphone input. For such a configuration the21 * volume control has no effect, since volume control only influences22 * the speaker output.23 *24 * There is no explicit mute/unmute. So I set the radio frequency to a25 * value where I do expect just noise and turn the speaker volume down.26 * The frequency change is necessary since the card never seems to be27 * completely silent.28 *29 * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@kernel.org>30 */31 32#include <linux/module.h> /* Modules */33#include <linux/init.h> /* Initdata */34#include <linux/ioport.h> /* request_region */35#include <linux/videodev2.h> /* kernel radio structs */36#include <linux/io.h> /* outb, outb_p */37#include <linux/slab.h>38#include <media/v4l2-device.h>39#include <media/v4l2-ioctl.h>40#include "radio-isa.h"41 42#define DRIVER_VERSION "0.1.2"43 44MODULE_AUTHOR("Dr. Henrik Seidel");45MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");46MODULE_LICENSE("GPL");47MODULE_VERSION("0.1.99");48 49#ifndef CONFIG_RADIO_TYPHOON_PORT50#define CONFIG_RADIO_TYPHOON_PORT -151#endif52 53#ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ54#define CONFIG_RADIO_TYPHOON_MUTEFREQ 8700055#endif56 57#define TYPHOON_MAX 258 59static int io[TYPHOON_MAX] = { [0] = CONFIG_RADIO_TYPHOON_PORT,60 [1 ... (TYPHOON_MAX - 1)] = -1 };61static int radio_nr[TYPHOON_MAX] = { [0 ... (TYPHOON_MAX - 1)] = -1 };62static unsigned long mutefreq = CONFIG_RADIO_TYPHOON_MUTEFREQ;63 64module_param_array(io, int, NULL, 0444);65MODULE_PARM_DESC(io, "I/O addresses of the Typhoon card (0x316 or 0x336)");66module_param_array(radio_nr, int, NULL, 0444);67MODULE_PARM_DESC(radio_nr, "Radio device numbers");68module_param(mutefreq, ulong, 0);69MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");70 71struct typhoon {72 struct radio_isa_card isa;73 int muted;74};75 76static struct radio_isa_card *typhoon_alloc(void)77{78 struct typhoon *ty = kzalloc(sizeof(*ty), GFP_KERNEL);79 80 return ty ? &ty->isa : NULL;81}82 83static int typhoon_s_frequency(struct radio_isa_card *isa, u32 freq)84{85 unsigned long outval;86 unsigned long x;87 88 /*89 * The frequency transfer curve is not linear. The best fit I could90 * get is91 *92 * outval = -155 + exp((f + 15.55) * 0.057))93 *94 * where frequency f is in MHz. Since we don't have exp in the kernel,95 * I approximate this function by a third order polynomial.96 *97 */98 99 x = freq / 160;100 outval = (x * x + 2500) / 5000;101 outval = (outval * x + 5000) / 10000;102 outval -= (10 * x * x + 10433) / 20866;103 outval += 4 * x - 11505;104 105 outb_p((outval >> 8) & 0x01, isa->io + 4);106 outb_p(outval >> 9, isa->io + 6);107 outb_p(outval & 0xff, isa->io + 8);108 return 0;109}110 111static int typhoon_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)112{113 struct typhoon *ty = container_of(isa, struct typhoon, isa);114 115 if (mute)116 vol = 0;117 vol >>= 14; /* Map 16 bit to 2 bit */118 vol &= 3;119 outb_p(vol / 2, isa->io); /* Set the volume, high bit. */120 outb_p(vol % 2, isa->io + 2); /* Set the volume, low bit. */121 122 if (vol == 0 && !ty->muted) {123 ty->muted = true;124 return typhoon_s_frequency(isa, mutefreq << 4);125 }126 if (vol && ty->muted) {127 ty->muted = false;128 return typhoon_s_frequency(isa, isa->freq);129 }130 return 0;131}132 133static const struct radio_isa_ops typhoon_ops = {134 .alloc = typhoon_alloc,135 .s_mute_volume = typhoon_s_mute_volume,136 .s_frequency = typhoon_s_frequency,137};138 139static const int typhoon_ioports[] = { 0x316, 0x336 };140 141static struct radio_isa_driver typhoon_driver = {142 .driver = {143 .match = radio_isa_match,144 .probe = radio_isa_probe,145 .remove = radio_isa_remove,146 .driver = {147 .name = "radio-typhoon",148 },149 },150 .io_params = io,151 .radio_nr_params = radio_nr,152 .io_ports = typhoon_ioports,153 .num_of_io_ports = ARRAY_SIZE(typhoon_ioports),154 .region_size = 8,155 .card = "Typhoon Radio",156 .ops = &typhoon_ops,157 .has_stereo = true,158 .max_volume = 3,159};160 161static int __init typhoon_init(void)162{163 if (mutefreq < 87000 || mutefreq > 108000) {164 printk(KERN_ERR "%s: You must set a frequency (in kHz) used when muting the card,\n",165 typhoon_driver.driver.driver.name);166 printk(KERN_ERR "%s: e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108000)\n",167 typhoon_driver.driver.driver.name);168 return -ENODEV;169 }170 return isa_register_driver(&typhoon_driver.driver, TYPHOON_MAX);171}172 173static void __exit typhoon_exit(void)174{175 isa_unregister_driver(&typhoon_driver.driver);176}177 178 179module_init(typhoon_init);180module_exit(typhoon_exit);181 182