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/*
* Radio Card Device Driver for Linux
*
* (c) 1997 Matthew Kirkwood <weejock@ferret.lmh.ox.ac.uk>
*
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <asm/uaccess.h>
#include <linux/config.h>
#include <linux/radio.h>
#ifdef CONFIG_RADIO_RTRACK
#include "rtrack.h"
#endif
#ifdef CONFIG_RADIO_WINRADIO
#include "winradio.h"
#endif
int radio_open(struct inode *inode, struct file *file);
int radio_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
/* /dev/radio interface */
static struct file_operations radio_fops = {
NULL, /* seek */
NULL, /* read */
NULL, /* write */
NULL, /* readdir */
NULL, /* select */
&radio_ioctl, /* ioctl */
NULL, /* mmap */
&radio_open, /* we're not allowed NULL, it seems... */
NULL /* release */
};
static struct miscdevice radio_miscdevice = {
RADIO_MINOR, /* minor device number */
"radio", /* title */
&radio_fops, /* file operations */
NULL, NULL /* previous and next (not our business) */
};
static struct radio_device *firstdevice, *lastdevice;
static int numdevices;
__initfunc(void radio_init(void))
{
/* register the handler for the device number... */
if(misc_register(&radio_miscdevice)) {
printk("radio: couldn't register misc device\n");
return;
}
/* do some general initialisation stuff */
lastdevice = firstdevice = NULL;
numdevices = 0;
#ifdef CONFIG_RADIO_RTRACK
radiotrack_init();
#endif
#ifdef CONFIG_RADIO_WINRADIO
printk("oooops. no winradio support yet... :-(\n");
#endif
/* etc.... */
printk("radio: registered %d devices\n", numdevices);
}
/* according to drivers/char/misc.c, the "open" call must not be NULL.
* I'm not sure if I approve, but I didn't write it, so...
*/
int radio_open(struct inode *inode, struct file *file)
{
return 0;
}
/* append a device to the linked list... */
int radio_add_device(struct radio_device *newdev)
{
if(firstdevice == NULL) {
firstdevice = newdev;
} else {
lastdevice->next = newdev;
}
lastdevice = newdev; numdevices++;
newdev->cap->dev_num=numdevices;
newdev->next = NULL; /* don't need, but... */
return(numdevices);
}
struct radio_device *getdev(int index)
{
struct radio_device *retval;
if(index > numdevices)
return NULL; /* let's have a bit less of that */
retval = firstdevice;
for(;index;index--)
retval = retval->next;
return retval;
}
/* interface routine */
int radio_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct radio_device *dev;
struct radio_ctl *ctl_arg = (struct radio_ctl*)arg;
int nowrite;
int val, ret;
if((void*)arg == NULL)
return -EFAULT; /* XXX - check errnos are OK */
switch(cmd) {
case RADIO_NUMDEVS:
return (put_user(numdevices,(int*)arg) ? -EFAULT : 0);
case RADIO_GETCAPS:
/* p'raps I should verify for read then write ?? */
if(verify_area(VERIFY_WRITE, (void*)arg, sizeof(struct radio_cap)))
return -EFAULT;
if((dev = getdev(((struct radio_cap*)arg)->dev_num)) == NULL)
return -EINVAL;
copy_to_user((void*)arg, dev->cap, sizeof(struct radio_cap));
return 0;
case RADIO_GETBNDCAP:
if(verify_area(VERIFY_WRITE, (void*)arg, sizeof(struct radio_band)))
return -EFAULT;
if((dev = getdev(((struct radio_band*)arg)->dev_num)) == NULL)
return -EINVAL;
val = ((struct radio_band*)arg)->index;
if(val >= dev->cap->num_bwidths)
return -EINVAL; /* XXX errno */
copy_to_user((void*)arg, (dev->bands)+(val*sizeof(struct radio_band)),
sizeof(struct radio_band));
return 0;
}
/* now, we know that arg points to a struct radio_ctl */
/* get the requested device */
if(verify_area(VERIFY_READ, ctl_arg, sizeof(struct radio_ctl)))
return -EFAULT;
if((dev = getdev(ctl_arg->dev_num)) == NULL)
return -EINVAL;
nowrite = verify_area(VERIFY_WRITE, ctl_arg, sizeof(struct radio_ctl));
val = ctl_arg->value;
switch(cmd) {
case RADIO_SETVOL:
if((val < dev->cap->volmin) || (val > dev->cap->volmax))
return -EINVAL;
if((ret = (*(dev->setvol))(dev, val)))
return ret;
dev->curvol = val;
return 0;
case RADIO_GETVOL:
if(nowrite)
return -EFAULT;
ctl_arg->value = dev->curvol;
return 0;
case RADIO_SETBAND:
if(val >= dev->cap->num_bwidths)
return -EINVAL;
if((ret = (*(dev->setband))(dev, val)))
return ret;
dev->curband = val;
return 0;
case RADIO_GETBAND:
if(nowrite)
return -EFAULT;
ctl_arg->value = dev->curband;
return 0;
case RADIO_SETFREQ: {
struct radio_band *bp;
bp = (dev->bands) + ((dev->curband) * sizeof(struct radio_band));
if((val < bp->freqmin) || (val > bp->freqmax))
return -EINVAL;
if((ret = (*(dev->setfreq))(dev, val)))
return ret;
dev->curfreq = val;
return 0;
}
case RADIO_GETFREQ:
if(nowrite)
return -EFAULT;
ctl_arg->value = dev->curfreq;
return 0;
case RADIO_GETSIGSTR:
if(nowrite)
return -EFAULT;
ctl_arg->value = (*(dev->getsigstr))(dev);
return 0;
default:
return -ENOSYS;
}
}
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