patch-2.1.63 linux/drivers/char/radio.c

• Lines: 235
• Date: Tue Nov 4 10:23:25 1997
• Orig file: v2.1.62/linux/drivers/char/radio.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.62/linux/drivers/char/radio.c linux/drivers/char/radio.c
@@ -0,0 +1,234 @@
+/*
+ * 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;
+	}
+}