https://github.com/torvalds/linux
Tip revision: c336923b668fdcf0312efbec3b44895d713f4d81 authored by Linus Torvalds on 04 September 2006, 02:19:48 UTC
Linux 2.6.18-rc6
Linux 2.6.18-rc6
Tip revision: c336923
radio-typhoon.c
/* Typhoon Radio Card driver for radio support
* (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de>
*
* Card manufacturer:
* http://194.18.155.92/idc/prod2.idc?nr=50753&lang=e
*
* 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.
*/
#include <linux/module.h> /* Modules */
#include <linux/init.h> /* Initdata */
#include <linux/ioport.h> /* request_region */
#include <linux/proc_fs.h> /* radio card status report */
#include <asm/io.h> /* outb, outb_p */
#include <asm/uaccess.h> /* copy to/from user */
#include <linux/videodev.h> /* kernel radio structs */
#include <media/v4l2-common.h>
#include <linux/config.h> /* CONFIG_RADIO_TYPHOON_* */
#define BANNER "Typhoon Radio Card driver v0.1\n"
#ifndef CONFIG_RADIO_TYPHOON_PORT
#define CONFIG_RADIO_TYPHOON_PORT -1
#endif
#ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ
#define CONFIG_RADIO_TYPHOON_MUTEFREQ 0
#endif
#ifndef CONFIG_PROC_FS
#undef CONFIG_RADIO_TYPHOON_PROC_FS
#endif
struct typhoon_device {
int users;
int iobase;
int curvol;
int muted;
unsigned long curfreq;
unsigned long mutefreq;
struct mutex lock;
};
static void typhoon_setvol_generic(struct typhoon_device *dev, int vol);
static int typhoon_setfreq_generic(struct typhoon_device *dev,
unsigned long frequency);
static int typhoon_setfreq(struct typhoon_device *dev, unsigned long frequency);
static void typhoon_mute(struct typhoon_device *dev);
static void typhoon_unmute(struct typhoon_device *dev);
static int typhoon_setvol(struct typhoon_device *dev, int vol);
static int typhoon_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg);
#ifdef CONFIG_RADIO_TYPHOON_PROC_FS
static int typhoon_get_info(char *buf, char **start, off_t offset, int len);
#endif
static void typhoon_setvol_generic(struct typhoon_device *dev, int vol)
{
mutex_lock(&dev->lock);
vol >>= 14; /* Map 16 bit to 2 bit */
vol &= 3;
outb_p(vol / 2, dev->iobase); /* Set the volume, high bit. */
outb_p(vol % 2, dev->iobase + 2); /* Set the volume, low bit. */
mutex_unlock(&dev->lock);
}
static int typhoon_setfreq_generic(struct typhoon_device *dev,
unsigned long frequency)
{
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.
*
*/
mutex_lock(&dev->lock);
x = frequency / 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, dev->iobase + 4);
outb_p(outval >> 9, dev->iobase + 6);
outb_p(outval & 0xff, dev->iobase + 8);
mutex_unlock(&dev->lock);
return 0;
}
static int typhoon_setfreq(struct typhoon_device *dev, unsigned long frequency)
{
typhoon_setfreq_generic(dev, frequency);
dev->curfreq = frequency;
return 0;
}
static void typhoon_mute(struct typhoon_device *dev)
{
if (dev->muted == 1)
return;
typhoon_setvol_generic(dev, 0);
typhoon_setfreq_generic(dev, dev->mutefreq);
dev->muted = 1;
}
static void typhoon_unmute(struct typhoon_device *dev)
{
if (dev->muted == 0)
return;
typhoon_setfreq_generic(dev, dev->curfreq);
typhoon_setvol_generic(dev, dev->curvol);
dev->muted = 0;
}
static int typhoon_setvol(struct typhoon_device *dev, int vol)
{
if (dev->muted && vol != 0) { /* user is unmuting the card */
dev->curvol = vol;
typhoon_unmute(dev);
return 0;
}
if (vol == dev->curvol) /* requested volume == current */
return 0;
if (vol == 0) { /* volume == 0 means mute the card */
typhoon_mute(dev);
dev->curvol = vol;
return 0;
}
typhoon_setvol_generic(dev, vol);
dev->curvol = vol;
return 0;
}
static int typhoon_do_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, void *arg)
{
struct video_device *dev = video_devdata(file);
struct typhoon_device *typhoon = dev->priv;
switch (cmd) {
case VIDIOCGCAP:
{
struct video_capability *v = arg;
memset(v,0,sizeof(*v));
v->type = VID_TYPE_TUNER;
v->channels = 1;
v->audios = 1;
strcpy(v->name, "Typhoon Radio");
return 0;
}
case VIDIOCGTUNER:
{
struct video_tuner *v = arg;
if (v->tuner) /* Only 1 tuner */
return -EINVAL;
v->rangelow = 875 * 1600;
v->rangehigh = 1080 * 1600;
v->flags = VIDEO_TUNER_LOW;
v->mode = VIDEO_MODE_AUTO;
v->signal = 0xFFFF; /* We can't get the signal strength */
strcpy(v->name, "FM");
return 0;
}
case VIDIOCSTUNER:
{
struct video_tuner *v = arg;
if (v->tuner != 0)
return -EINVAL;
/* Only 1 tuner so no setting needed ! */
return 0;
}
case VIDIOCGFREQ:
{
unsigned long *freq = arg;
*freq = typhoon->curfreq;
return 0;
}
case VIDIOCSFREQ:
{
unsigned long *freq = arg;
typhoon->curfreq = *freq;
typhoon_setfreq(typhoon, typhoon->curfreq);
return 0;
}
case VIDIOCGAUDIO:
{
struct video_audio *v = arg;
memset(v, 0, sizeof(*v));
v->flags |= VIDEO_AUDIO_MUTABLE | VIDEO_AUDIO_VOLUME;
v->mode |= VIDEO_SOUND_MONO;
v->volume = typhoon->curvol;
v->step = 1 << 14;
strcpy(v->name, "Typhoon Radio");
return 0;
}
case VIDIOCSAUDIO:
{
struct video_audio *v = arg;
if (v->audio)
return -EINVAL;
if (v->flags & VIDEO_AUDIO_MUTE)
typhoon_mute(typhoon);
else
typhoon_unmute(typhoon);
if (v->flags & VIDEO_AUDIO_VOLUME)
typhoon_setvol(typhoon, v->volume);
return 0;
}
default:
return -ENOIOCTLCMD;
}
}
static int typhoon_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
return video_usercopy(inode, file, cmd, arg, typhoon_do_ioctl);
}
static struct typhoon_device typhoon_unit =
{
.iobase = CONFIG_RADIO_TYPHOON_PORT,
.curfreq = CONFIG_RADIO_TYPHOON_MUTEFREQ,
.mutefreq = CONFIG_RADIO_TYPHOON_MUTEFREQ,
};
static struct file_operations typhoon_fops = {
.owner = THIS_MODULE,
.open = video_exclusive_open,
.release = video_exclusive_release,
.ioctl = typhoon_ioctl,
.compat_ioctl = v4l_compat_ioctl32,
.llseek = no_llseek,
};
static struct video_device typhoon_radio =
{
.owner = THIS_MODULE,
.name = "Typhoon Radio",
.type = VID_TYPE_TUNER,
.hardware = VID_HARDWARE_TYPHOON,
.fops = &typhoon_fops,
};
#ifdef CONFIG_RADIO_TYPHOON_PROC_FS
static int typhoon_get_info(char *buf, char **start, off_t offset, int len)
{
char *out = buf;
#ifdef MODULE
#define MODULEPROCSTRING "Driver loaded as a module"
#else
#define MODULEPROCSTRING "Driver compiled into kernel"
#endif
/* output must be kept under PAGE_SIZE */
out += sprintf(out, BANNER);
out += sprintf(out, "Load type: " MODULEPROCSTRING "\n\n");
out += sprintf(out, "frequency = %lu kHz\n",
typhoon_unit.curfreq >> 4);
out += sprintf(out, "volume = %d\n", typhoon_unit.curvol);
out += sprintf(out, "mute = %s\n", typhoon_unit.muted ?
"on" : "off");
out += sprintf(out, "iobase = 0x%x\n", typhoon_unit.iobase);
out += sprintf(out, "mute frequency = %lu kHz\n",
typhoon_unit.mutefreq >> 4);
return out - buf;
}
#endif /* CONFIG_RADIO_TYPHOON_PROC_FS */
MODULE_AUTHOR("Dr. Henrik Seidel");
MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");
MODULE_LICENSE("GPL");
static int io = -1;
static int radio_nr = -1;
module_param(io, int, 0);
MODULE_PARM_DESC(io, "I/O address of the Typhoon card (0x316 or 0x336)");
module_param(radio_nr, int, 0);
#ifdef MODULE
static unsigned long mutefreq = 0;
module_param(mutefreq, ulong, 0);
MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");
#endif
static int __init typhoon_init(void)
{
#ifdef MODULE
if (io == -1) {
printk(KERN_ERR "radio-typhoon: You must set an I/O address with io=0x316 or io=0x336\n");
return -EINVAL;
}
typhoon_unit.iobase = io;
if (mutefreq < 87000 || mutefreq > 108500) {
printk(KERN_ERR "radio-typhoon: You must set a frequency (in kHz) used when muting the card,\n");
printk(KERN_ERR "radio-typhoon: e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108500)\n");
return -EINVAL;
}
typhoon_unit.mutefreq = mutefreq;
#endif /* MODULE */
printk(KERN_INFO BANNER);
mutex_init(&typhoon_unit.lock);
io = typhoon_unit.iobase;
if (!request_region(io, 8, "typhoon")) {
printk(KERN_ERR "radio-typhoon: port 0x%x already in use\n",
typhoon_unit.iobase);
return -EBUSY;
}
typhoon_radio.priv = &typhoon_unit;
if (video_register_device(&typhoon_radio, VFL_TYPE_RADIO, radio_nr) == -1)
{
release_region(io, 8);
return -EINVAL;
}
printk(KERN_INFO "radio-typhoon: port 0x%x.\n", typhoon_unit.iobase);
printk(KERN_INFO "radio-typhoon: mute frequency is %lu kHz.\n",
typhoon_unit.mutefreq);
typhoon_unit.mutefreq <<= 4;
/* mute card - prevents noisy bootups */
typhoon_mute(&typhoon_unit);
#ifdef CONFIG_RADIO_TYPHOON_PROC_FS
if (!create_proc_info_entry("driver/radio-typhoon", 0, NULL,
typhoon_get_info))
printk(KERN_ERR "radio-typhoon: registering /proc/driver/radio-typhoon failed\n");
#endif
return 0;
}
static void __exit typhoon_cleanup_module(void)
{
#ifdef CONFIG_RADIO_TYPHOON_PROC_FS
remove_proc_entry("driver/radio-typhoon", NULL);
#endif
video_unregister_device(&typhoon_radio);
release_region(io, 8);
}
module_init(typhoon_init);
module_exit(typhoon_cleanup_module);