1 files changed, 331 insertions, 0 deletions

diff --git a/drivers/char/misc.c b/drivers/char/misc.c
new file mode 100644
index 000000000000..0937544762da
--- /dev/null
+++ b/drivers/char/misc.c
@@ -0,0 +1,331 @@
+/*
+ * 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-Mar-96
+ *
+ * Handling of mouse minor numbers for kerneld:
+ *  Idea by Jacques Gelinas <jack@solucorp.qc.ca>,
+ *  adapted by Bjorn Ekwall <bj0rn@blox.se>
+ *  corrected by Alan Cox <alan@lxorguk.ukuu.org.uk>
+ *
+ * Changes for kmod (from kerneld):
+ *      Cyrus Durgin <cider@speakeasy.org>
+ *
+ * Added devfs support. Richard Gooch <rgooch@atnf.csiro.au>  10-Jan-1998
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/tty.h>
+#include <linux/kmod.h>
+
+/*
+ * Head entry for the doubly linked miscdevice list
+ */
+static LIST_HEAD(misc_list);
+static DECLARE_MUTEX(misc_sem);
+
+/*
+ * Assigned numbers, used for dynamic minors
+ */
+#define DYNAMIC_MINORS 64 /* like dynamic majors */
+static unsigned char misc_minors[DYNAMIC_MINORS / 8];
+
+extern int rtc_DP8570A_init(void);
+extern int rtc_MK48T08_init(void);
+extern int pmu_device_init(void);
+extern int tosh_init(void);
+extern int i8k_init(void);
+
+#ifdef CONFIG_PROC_FS
+static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
+{
+        struct miscdevice *p;
+        loff_t off = 0;
+
+        down(&misc_sem);
+        list_for_each_entry(p, &misc_list, list) {
+                if (*pos == off++) 
+                        return p;
+        }
+        return NULL;
+}
+
+static void *misc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+        struct list_head *n = ((struct miscdevice *)v)->list.next;
+
+        ++*pos;
+
+        return (n != &misc_list) ? list_entry(n, struct miscdevice, list)
+                 : NULL;
+}
+
+static void misc_seq_stop(struct seq_file *seq, void *v)
+{
+        up(&misc_sem);
+}
+
+static int misc_seq_show(struct seq_file *seq, void *v)
+{
+        const struct miscdevice *p = v;
+
+        seq_printf(seq, "%3i %s\n", p->minor, p->name ? p->name : "");
+        return 0;
+}
+
+
+static struct seq_operations misc_seq_ops = {
+        .start = misc_seq_start,
+        .next  = misc_seq_next,
+        .stop  = misc_seq_stop,
+        .show  = misc_seq_show,
+};
+
+static int misc_seq_open(struct inode *inode, struct file *file)
+{
+        return seq_open(file, &misc_seq_ops);
+}
+
+static struct file_operations misc_proc_fops = {
+        .owner   = THIS_MODULE,
+        .open    = misc_seq_open,
+        .read    = seq_read,
+        .llseek  = seq_lseek,
+        .release = seq_release,
+};
+#endif
+
+static int misc_open(struct inode * inode, struct file * file)
+{
+        int minor = iminor(inode);
+        struct miscdevice *c;
+        int err = -ENODEV;
+        struct file_operations *old_fops, *new_fops = NULL;
+        
+        down(&misc_sem);
+        
+        list_for_each_entry(c, &misc_list, list) {
+                if (c->minor == minor) {
+                        new_fops = fops_get(c->fops);           
+                        break;
+                }
+        }
+                
+        if (!new_fops) {
+                up(&misc_sem);
+                request_module("char-major-%d-%d", MISC_MAJOR, minor);
+                down(&misc_sem);
+
+                list_for_each_entry(c, &misc_list, list) {
+                        if (c->minor == minor) {
+                                new_fops = fops_get(c->fops);
+                                break;
+                        }
+                }
+                if (!new_fops)
+                        goto fail;
+        }
+
+        err = 0;
+        old_fops = file->f_op;
+        file->f_op = new_fops;
+        if (file->f_op->open) {
+                err=file->f_op->open(inode,file);
+                if (err) {
+                        fops_put(file->f_op);
+                        file->f_op = fops_get(old_fops);
+                }
+        }
+        fops_put(old_fops);
+fail:
+        up(&misc_sem);
+        return err;
+}
+
+/* 
+ * TODO for 2.7:
+ *  - add a struct class_device to struct miscdevice and make all usages of
+ *    them dynamic.
+ */
+static struct class_simple *misc_class;
+
+static struct file_operations misc_fops = {
+        .owner          = THIS_MODULE,
+        .open           = misc_open,
+};
+
+
+/**
+ *      misc_register   -       register a miscellaneous device
+ *      @misc: device structure
+ *      
+ *      Register a miscellaneous device with the kernel. If the minor
+ *      number is set to %MISC_DYNAMIC_MINOR a minor number is assigned
+ *      and placed in the minor field of the structure. For other cases
+ *      the minor number requested is used.
+ *
+ *      The structure passed is linked into the kernel and may not be
+ *      destroyed until it has been unregistered.
+ *
+ *      A zero is returned on success and a negative errno code for
+ *      failure.
+ */
+ 
+int misc_register(struct miscdevice * misc)
+{
+        struct miscdevice *c;
+        dev_t dev;
+        int err;
+
+        down(&misc_sem);
+        list_for_each_entry(c, &misc_list, list) {
+                if (c->minor == misc->minor) {
+                        up(&misc_sem);
+                        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) {
+                        up(&misc_sem);
+                        return -EBUSY;
+                }
+                misc->minor = i;
+        }
+
+        if (misc->minor < DYNAMIC_MINORS)
+                misc_minors[misc->minor >> 3] |= 1 << (misc->minor & 7);
+        if (misc->devfs_name[0] == '\0') {
+                snprintf(misc->devfs_name, sizeof(misc->devfs_name),
+                                "misc/%s", misc->name);
+        }
+        dev = MKDEV(MISC_MAJOR, misc->minor);
+
+        misc->class = class_simple_device_add(misc_class, dev,
+                                              misc->dev, misc->name);
+        if (IS_ERR(misc->class)) {
+                err = PTR_ERR(misc->class);
+                goto out;
+        }
+
+        err = devfs_mk_cdev(dev, S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP, 
+                            misc->devfs_name);
+        if (err) {
+                class_simple_device_remove(dev);
+                goto out;
+        }
+
+        /*
+         * Add it to the front, so that later devices can "override"
+         * earlier defaults
+         */
+        list_add(&misc->list, &misc_list);
+ out:
+        up(&misc_sem);
+        return err;
+}
+
+/**
+ *      misc_deregister - unregister a miscellaneous device
+ *      @misc: device to unregister
+ *
+ *      Unregister a miscellaneous device that was previously
+ *      successfully registered with misc_register(). Success
+ *      is indicated by a zero return, a negative errno code
+ *      indicates an error.
+ */
+
+int misc_deregister(struct miscdevice * misc)
+{
+        int i = misc->minor;
+
+        if (list_empty(&misc->list))
+                return -EINVAL;
+
+        down(&misc_sem);
+        list_del(&misc->list);
+        class_simple_device_remove(MKDEV(MISC_MAJOR, misc->minor));
+        devfs_remove(misc->devfs_name);
+        if (i < DYNAMIC_MINORS && i>0) {
+                misc_minors[i>>3] &= ~(1 << (misc->minor & 7));
+        }
+        up(&misc_sem);
+        return 0;
+}
+
+EXPORT_SYMBOL(misc_register);
+EXPORT_SYMBOL(misc_deregister);
+
+static int __init misc_init(void)
+{
+#ifdef CONFIG_PROC_FS
+        struct proc_dir_entry *ent;
+
+        ent = create_proc_entry("misc", 0, NULL);
+        if (ent)
+                ent->proc_fops = &misc_proc_fops;
+#endif
+        misc_class = class_simple_create(THIS_MODULE, "misc");
+        if (IS_ERR(misc_class))
+                return PTR_ERR(misc_class);
+#ifdef CONFIG_MVME16x
+        rtc_MK48T08_init();
+#endif
+#ifdef CONFIG_BVME6000
+        rtc_DP8570A_init();
+#endif
+#ifdef CONFIG_PMAC_PBOOK
+        pmu_device_init();
+#endif
+#ifdef CONFIG_TOSHIBA
+        tosh_init();
+#endif
+#ifdef CONFIG_I8K
+        i8k_init();
+#endif
+        if (register_chrdev(MISC_MAJOR,"misc",&misc_fops)) {
+                printk("unable to get major %d for misc devices\n",
+                       MISC_MAJOR);
+                class_simple_destroy(misc_class);
+                return -EIO;
+        }
+        return 0;
+}
+subsys_initcall(misc_init);