/* Typhoon Radio Card driver for radio support
* (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de>
*
* Notes on the hardware
*
* This card has two output sockets, one for speakers and one for line.
* The speaker output has volume control, but only in four discrete
* steps. The line output has neither volume control nor mute.
*
* The card has auto-stereo according to its manual, although it all
* sounds mono to me (even with the Win/DOS drivers). Maybe it's my
* antenna - I really don't know for sure.
*
* Frequency control is done digitally.
*
* Volume control is done digitally, but there are only four different
* possible values. So you should better always turn the volume up and
* use line control. I got the best results by connecting line output
* to the sound card microphone input. For such a configuration the
* volume control has no effect, since volume control only influences
* the speaker output.
*
* There is no explicit mute/unmute. So I set the radio frequency to a
* value where I do expect just noise and turn the speaker volume down.
* The frequency change is necessary since the card never seems to be
* completely silent.
*
* Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>
*/
#include <linux/module.h> /* Modules */
#include <linux/init.h> /* Initdata */
#include <linux/ioport.h> /* request_region */
#include <linux/videodev2.h> /* kernel radio structs */
#include <linux/io.h> /* outb, outb_p */
#include <linux/slab.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include "radio-isa.h"
#define DRIVER_VERSION "0.1.2"
MODULE_AUTHOR("Dr. Henrik Seidel");
MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.1.99");
#ifndef CONFIG_RADIO_TYPHOON_PORT
#define CONFIG_RADIO_TYPHOON_PORT -1
#endif
#ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ
#define CONFIG_RADIO_TYPHOON_MUTEFREQ 87000
#endif
#define TYPHOON_MAX 2
static int io[TYPHOON_MAX] = { [0] = CONFIG_RADIO_TYPHOON_PORT,
[1 ... (TYPHOON_MAX - 1)] = -1 };
static int radio_nr[TYPHOON_MAX] = { [0 ... (TYPHOON_MAX - 1)] = -1 };
static unsigned long mutefreq = CONFIG_RADIO_TYPHOON_MUTEFREQ;
module_param_array(io, int, NULL, 0444);
MODULE_PARM_DESC(io, "I/O addresses of the Typhoon card (0x316 or 0x336)");
module_param_array(radio_nr, int, NULL, 0444);
MODULE_PARM_DESC(radio_nr, "Radio device numbers");
module_param(mutefreq, ulong, 0);
MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");
struct typhoon {
struct radio_isa_card isa;
int muted;
};
static struct radio_isa_card *typhoon_alloc(void)
{
struct typhoon *ty = kzalloc(sizeof(*ty), GFP_KERNEL);
return ty ? &ty->isa : NULL;
}
static int typhoon_s_frequency(struct radio_isa_card *isa, u32 freq)
{
unsigned long outval;
unsigned long x;
/*
* The frequency transfer curve is not linear. The best fit I could
* get is
*
* outval = -155 + exp((f + 15.55) * 0.057))
*
* where frequency f is in MHz. Since we don't have exp in the kernel,
* I approximate this function by a third order polynomial.
*
*/
x = freq / 160;
outval = (x * x + 2500) / 5000;
outval = (outval * x + 5000) / 10000;
outval -= (10 * x * x + 10433) / 20866;
outval += 4 * x - 11505;
outb_p((outval >> 8) & 0x01, isa->io + 4);
outb_p(outval >> 9, isa->io + 6);
outb_p(outval & 0xff, isa->io + 8);
return 0;
}
static int typhoon_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
{
struct typhoon *ty = container_of(isa, struct typhoon, isa);
if (mute)
vol = 0;
vol >>= 14; /* Map 16 bit to 2 bit */
vol &= 3;
outb_p(vol / 2, isa->io); /* Set the volume, high bit. */
outb_p(vol % 2, isa->io + 2); /* Set the volume, low bit. */
if (vol == 0 && !ty->muted) {
ty->muted = true;
return typhoon_s_frequency(isa, mutefreq << 4);
}
if (vol && ty->muted) {
ty->muted = false;
return typhoon_s_frequency(isa, isa->freq);
}
return 0;
}
static const struct radio_isa_ops typhoon_ops = {
.alloc = typhoon_alloc,
.s_mute_volume = typhoon_s_mute_volume,
.s_frequency = typhoon_s_frequency,
};
static const int typhoon_ioports[] = { 0x316, 0x336 };
static struct radio_isa_driver typhoon_driver = {
.driver = {
.match = radio_isa_match,
.probe = radio_isa_probe,
.remove = radio_isa_remove,
.driver = {
.name = "radio-typhoon",
},
},
.io_params = io,
.radio_nr_params = radio_nr,
.io_ports = typhoon_ioports,
.num_of_io_ports = ARRAY_SIZE(typhoon_ioports),
.region_size = 8,
.card = "Typhoon Radio",
.ops = &typhoon_ops,
.has_stereo = true,
.max_volume = 3,
};
static int __init typhoon_init(void)
{
if (mutefreq < 87000 || mutefreq > 108000) {
printk(KERN_ERR "%s: You must set a frequency (in kHz) used when muting the card,\n",
typhoon_driver.driver.driver.name);
printk(KERN_ERR "%s: e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108000)\n",
typhoon_driver.driver.driver.name);
return -ENODEV;
}
return isa_register_driver(&typhoon_driver.driver, TYPHOON_MAX);
}
static void __exit typhoon_exit(void)
{
isa_unregister_driver(&typhoon_driver.driver);
}
module_init(typhoon_init);
module_exit(typhoon_exit);
