drivers/atm/adummy.c

   1 /*
   2  * adummy.c: a dummy ATM driver
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/kernel.h>
   7 #include <linux/skbuff.h>
   8 #include <linux/errno.h>
   9 #include <linux/types.h>
  10 #include <linux/string.h>
  11 #include <linux/delay.h>
  12 #include <linux/init.h>
  13 #include <linux/mm.h>
  14 #include <linux/timer.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/slab.h>
  17 #include <asm/io.h>
  18 #include <asm/byteorder.h>
  19 #include <asm/uaccess.h>
  20
  21 #include <linux/atmdev.h>
  22 #include <linux/atm.h>
  23 #include <linux/sonet.h>
  24
  25 /* version definition */
  26
  27 #define DRV_VERSION "1.0"
  28
  29 #define DEV_LABEL "adummy"
  30
  31 #define ADUMMY_DEV(dev) ((struct adummy_dev *) (dev)->dev_data)
  32
  33 struct adummy_dev {
  34         struct atm_dev *atm_dev;
  35
  36         struct list_head entry;
  37 };
  38
  39 /* globals */
  40
  41 static LIST_HEAD(adummy_devs);
  42
  43 static int __init
  44 adummy_start(struct atm_dev *dev)
  45 {
  46         dev->ci_range.vpi_bits = 4;
  47         dev->ci_range.vci_bits = 12;
  48
  49         return 0;
  50 }
  51
  52 static int
  53 adummy_open(struct atm_vcc *vcc)
  54 {
  55         short vpi = vcc->vpi;
  56         int vci = vcc->vci;
  57
  58         if (vci == ATM_VCI_UNSPEC || vpi == ATM_VPI_UNSPEC)
  59                 return 0;
  60
  61         set_bit(ATM_VF_ADDR, &vcc->flags);
  62         set_bit(ATM_VF_READY, &vcc->flags);
  63
  64         return 0;
  65 }
  66
  67 static void
  68 adummy_close(struct atm_vcc *vcc)
  69 {
  70         clear_bit(ATM_VF_READY, &vcc->flags);
  71         clear_bit(ATM_VF_ADDR, &vcc->flags);
  72 }
  73
  74 static int
  75 adummy_send(struct atm_vcc *vcc, struct sk_buff *skb)
  76 {
  77         if (vcc->pop)
  78                 vcc->pop(vcc, skb);
  79         else
  80                 dev_kfree_skb_any(skb);
  81         atomic_inc(&vcc->stats->tx);
  82
  83         return 0;
  84 }
  85
  86 static int
  87 adummy_proc_read(struct atm_dev *dev, loff_t *pos, char *page)
  88 {
  89         int left = *pos;
  90
  91         if (!left--)
  92                 return sprintf(page, "version %s\n", DRV_VERSION);
  93
  94         return 0;
  95 }
  96
  97 static struct atmdev_ops adummy_ops =
  98 {
  99         .open =         adummy_open,
 100         .close =        adummy_close,
 101         .send =         adummy_send,
 102         .proc_read =    adummy_proc_read,
 103         .owner =        THIS_MODULE
 104 };
 105
 106 static int __init adummy_init(void)
 107 {
 108         struct atm_dev *atm_dev;
 109         struct adummy_dev *adummy_dev;
 110         int err = 0;
 111
 112         printk(KERN_ERR "adummy: version %s\n", DRV_VERSION);
 113
 114         adummy_dev = kzalloc(sizeof(struct adummy_dev),
 115                                                    GFP_KERNEL);
 116         if (!adummy_dev) {
 117                 printk(KERN_ERR DEV_LABEL ": kzalloc() failed\n");
 118                 err = -ENOMEM;
 119                 goto out;
 120         }
 121         atm_dev = atm_dev_register(DEV_LABEL, &adummy_ops, -1, NULL);
 122         if (!atm_dev) {
 123                 printk(KERN_ERR DEV_LABEL ": atm_dev_register() failed\n");
 124                 err = -ENODEV;
 125                 goto out_kfree;
 126         }
 127
 128         adummy_dev->atm_dev = atm_dev;
 129         atm_dev->dev_data = adummy_dev;
 130
 131         if (adummy_start(atm_dev)) {
 132                 printk(KERN_ERR DEV_LABEL ": adummy_start() failed\n");
 133                 err = -ENODEV;
 134                 goto out_unregister;
 135         }
 136
 137         list_add(&adummy_dev->entry, &adummy_devs);
 138 out:
 139         return err;
 140
 141 out_unregister:
 142         atm_dev_deregister(atm_dev);
 143 out_kfree:
 144         kfree(adummy_dev);
 145         goto out;
 146 }
 147
 148 static void __exit adummy_cleanup(void)
 149 {
 150         struct adummy_dev *adummy_dev, *next;
 151
 152         list_for_each_entry_safe(adummy_dev, next, &adummy_devs, entry) {
 153                 atm_dev_deregister(adummy_dev->atm_dev);
 154                 kfree(adummy_dev);
 155         }
 156 }
 157
 158 module_init(adummy_init);
 159 module_exit(adummy_cleanup);
 160
 161 MODULE_AUTHOR("chas williams <chas@cmf.nrl.navy.mil>");
 162 MODULE_DESCRIPTION("dummy ATM driver");
 163 MODULE_LICENSE("GPL");