patch-1.3.81 linux/drivers/char/misc.c

• Lines: 205
• Date: Sat Mar 30 13:20:33 1996
• Orig file: v1.3.80/linux/drivers/char/misc.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.80/linux/drivers/char/misc.c linux/drivers/char/misc.c
@@ -0,0 +1,204 @@
+/*
+ * linux/drivers/char/misc.c
+ *
+ * Generic misc open routine by Johan Myreen
+ *
+ * Based on code from Linus
+ *
+ * Teemu Rantanen's Microsoft Busmouse support and Derrick Cole's
+ *   changes incorporated into 0.97pl4
+ *   by Peter Cervasio (pete%q106fm.uucp@wupost.wustl.edu) (08SEP92)
+ *   See busmouse.c for particulars.
+ *
+ * Made things a lot mode modular - easy to compile in just one or two
+ * of the misc drivers, as they are now completely independent. Linus.
+ *
+ * Support for loadable modules. 8-Sep-95 Philip Blundell <pjb27@cam.ac.uk>
+ *
+ * Fixed a failing symbol register to free the device registration
+ *		Alan Cox <alan@lxorguk.ukuu.org.uk> 21-Jan-96
+ *
+ * Dynamic minors and /proc/mice by Alessandro Rubini. 26-Mar-96
+ *
+ * Renamed to misc and miscdevice to be more accurate. Alan Cox 26-May-96
+ */
+
+#include <linux/module.h>
+
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/malloc.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+
+#include <linux/tty.h> /* needed by selection.h */
+#include "selection.h" /* export its symbols */
+
+/*
+ * Head entry for the doubly linked miscdevice list
+ */
+static struct miscdevice misc_list = { 0, "head", NULL, &misc_list, &misc_list };
+
+/*
+ * Assigned numbers, used for dynamic minors
+ */
+#define DYNAMIC_MINORS 64 /* like dynamic majors */
+static unsigned char misc_minors[DYNAMIC_MINORS / 8];
+
+#ifndef MODULE
+extern int bus_mouse_init(void);
+extern int psaux_init(void);
+extern int ms_bus_mouse_init(void);
+extern int atixl_busmouse_init(void);
+extern void watchdog_init(void);
+
+#ifdef CONFIG_PROC_FS
+static int proc_misc_read(char *buf, char **start, off_t offset, int len, int unused)
+{
+	struct miscdevice *p;
+
+	len=0;
+	for (p = misc_list.next; p != &misc_list; p = p->next)
+		len += sprintf(buf+len, "%3i %s\n",p->minor, p->name ?: "");
+	return len;
+}
+
+#endif /* PROC_FS */
+#endif /* !MODULE */
+
+static int misc_open(struct inode * inode, struct file * file)
+{
+	int minor = MINOR(inode->i_rdev);
+	struct miscdevice *c = misc_list.next;
+	file->f_op = NULL;
+
+	while (c != &misc_list) {
+		if (c->minor == minor) {
+			file->f_op = c->fops;
+			break;
+		}
+		c = c->next;
+	}
+
+	if (file->f_op == NULL)
+		return -ENODEV;
+        return file->f_op->open(inode,file);
+}
+
+static struct file_operations misc_fops = {
+        NULL,		/* seek */
+	NULL,		/* read */
+	NULL,		/* write */
+	NULL,		/* readdir */
+	NULL,		/* select */
+	NULL,		/* ioctl */
+	NULL,		/* mmap */
+        misc_open,
+        NULL		/* release */
+};
+
+int misc_register(struct miscdevice * misc)
+{
+	if (misc->next || misc->prev)
+		return -EBUSY;
+	if (misc->minor == MISC_DYNAMIC_MINOR) {
+		int i = DYNAMIC_MINORS;
+		while (--i >= 0)
+			if ( (misc_minors[i>>3] & (1 << (i&7))) == 0)
+				break;
+		if (i<0) return -EBUSY;
+		misc->minor = i;
+	}
+	if (misc->minor < DYNAMIC_MINORS)
+		misc_minors[misc->minor >> 3] |= 1 << (misc->minor & 7);
+	MOD_INC_USE_COUNT;
+	misc->next = &misc_list;
+	misc->prev = misc_list.prev;
+	misc->prev->next = misc;
+	misc->next->prev = misc;
+	return 0;
+}
+
+int misc_deregister(struct miscdevice * misc)
+{
+	int i = misc->minor;
+	if (!misc->next || !misc->prev)
+		return -EINVAL;
+	MOD_DEC_USE_COUNT;
+	misc->prev->next = misc->next;
+	misc->next->prev = misc->prev;
+	misc->next = NULL;
+	misc->prev = NULL;
+	if (i < DYNAMIC_MINORS && i>0) {
+		misc_minors[i>>3] &= ~(1 << (misc->minor & 7));
+	}
+	return 0;
+}
+
+#ifdef MODULE
+
+#define misc_init init_module
+
+void cleanup_module(void)
+{
+	unregister_chrdev(MOUSE_MAJOR, "misc");
+}
+
+#endif
+
+static struct symbol_table misc_syms = {
+/* Should this be surrounded with "#ifdef CONFIG_MODULES" ? */
+#include <linux/symtab_begin.h>
+	X(misc_register),
+	X(misc_deregister),
+#ifndef MODULE
+	X(set_selection),   /* used by the kmisc module, can only */
+	X(clear_selection), /* be exported if misc.c is in linked in */
+#endif
+#include <linux/symtab_end.h>
+};
+
+int misc_init(void)
+{
+#ifndef MODULE
+#ifdef CONFIG_PROC_FS
+	proc_register_dynamic(&proc_root, &(struct proc_dir_entry) {
+		0, 4, "misc",
+		S_IRUGO, 1, 0, 0,
+		0, NULL /* ops -- default to array */,
+		&proc_misc_read /* get_info */,
+	});	
+#endif /* PROC_FS */
+#ifdef CONFIG_BUSMOUSE
+	bus_mouse_init();
+#endif
+#if defined CONFIG_PSMOUSE || defined CONFIG_82C710_MOUSE
+	psaux_init();
+#endif
+#ifdef CONFIG_MS_BUSMOUSE
+	ms_bus_mouse_init();
+#endif
+#ifdef CONFIG_ATIXL_BUSMOUSE
+ 	atixl_busmouse_init();
+#endif
+#ifdef CONFIG_SOFT_WATCHDOG
+	watchdog_init();
+#endif	
+#endif /* !MODULE */
+	if (register_chrdev(MISC_MAJOR,"misc",&misc_fops)) {
+	  printk("unable to get major %d for misc devices\n",
+		 MISC_MAJOR);
+		return -EIO;
+	}
+
+	if(register_symtab(&misc_syms)!=0)
+	{
+		unregister_chrdev(MISC_MAJOR, "misc");
+		return -EIO;
+	}
+	return 0;
+}