1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Typhoon Radio Card driver for radio support 3 * (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de> 4 * 5 * Notes on the hardware 6 * 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 discrete 9 * steps. The line output has neither volume control nor mute. 10 * 11 * The card has auto-stereo according to its manual, although it all 12 * sounds mono to me (even with the Win/DOS drivers). Maybe it's my 13 * 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 different 18 * possible values. So you should better always turn the volume up and 19 * use line control. I got the best results by connecting line output 20 * to the sound card microphone input. For such a configuration the 21 * volume control has no effect, since volume control only influences 22 * the speaker output. 23 * 24 * There is no explicit mute/unmute. So I set the radio frequency to a 25 * 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 be 27 * 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 44 MODULE_AUTHOR("Dr. Henrik Seidel"); 45 MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio)."); 46 MODULE_LICENSE("GPL"); 47 MODULE_VERSION("0.1.99"); 48 49 #ifndef CONFIG_RADIO_TYPHOON_PORT 50 #define CONFIG_RADIO_TYPHOON_PORT -1 51 #endif 52 53 #ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ 54 #define CONFIG_RADIO_TYPHOON_MUTEFREQ 87000 55 #endif 56 57 #define TYPHOON_MAX 2 58 59 static int io[TYPHOON_MAX] = { [0] = CONFIG_RADIO_TYPHOON_PORT, 60 [1 ... (TYPHOON_MAX - 1)] = -1 }; 61 static int radio_nr[TYPHOON_MAX] = { [0 ... (TYPHOON_MAX - 1)] = -1 }; 62 static unsigned long mutefreq = CONFIG_RADIO_TYPHOON_MUTEFREQ; 63 64 module_param_array(io, int, NULL, 0444); 65 MODULE_PARM_DESC(io, "I/O addresses of the Typhoon card (0x316 or 0x336)"); 66 module_param_array(radio_nr, int, NULL, 0444); 67 MODULE_PARM_DESC(radio_nr, "Radio device numbers"); 68 module_param(mutefreq, ulong, 0); 69 MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)"); 70 71 struct typhoon { 72 struct radio_isa_card isa; 73 int muted; 74 }; 75 76 static 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 83 static 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 could 90 * get is 91 * 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 } 110 111 static 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 } 132 133 static 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 }; 138 139 static const int typhoon_ioports[] = { 0x316, 0x336 }; 140 141 static 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 }; 160 161 static 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 } 172 173 static void __exit typhoon_exit(void) 174 { 175 isa_unregister_driver(&typhoon_driver.driver); 176 } 177 178 179 module_init(typhoon_init); 180 module_exit(typhoon_exit); 181 182