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 <linux/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 ssize_t __set_signal(struct device *dev,
  44                 struct device_attribute *attr,
  45                 const char *buf, size_t len)
  46 {
  47         struct atm_dev *atm_dev = container_of(dev, struct atm_dev, class_dev);
  48         int signal;
  49
  50         if (sscanf(buf, "%d", &signal) == 1) {
  51
  52                 if (signal < ATM_PHY_SIG_LOST || signal > ATM_PHY_SIG_FOUND)
  53                         signal = ATM_PHY_SIG_UNKNOWN;
  54
  55                 atm_dev_signal_change(atm_dev, signal);
  56                 return 1;
  57         }
  58         return -EINVAL;
  59 }
  60
  61 static ssize_t __show_signal(struct device *dev,
  62         struct device_attribute *attr, char *buf)
  63 {
  64         struct atm_dev *atm_dev = container_of(dev, struct atm_dev, class_dev);
  65         return sprintf(buf, "%d\n", atm_dev->signal);
  66 }
  67 static DEVICE_ATTR(signal, 0644, __show_signal, __set_signal);
  68
  69 static struct attribute *adummy_attrs[] = {
  70         &dev_attr_signal.attr,
  71         NULL
  72 };
  73
  74 static const struct attribute_group adummy_group_attrs = {
  75         .name = NULL, /* We want them in dev's root folder */
  76         .attrs = adummy_attrs
  77 };
  78
  79 static int __init
  80 adummy_start(struct atm_dev *dev)
  81 {
  82         dev->ci_range.vpi_bits = 4;
  83         dev->ci_range.vci_bits = 12;
  84
  85         return 0;
  86 }
  87
  88 static int
  89 adummy_open(struct atm_vcc *vcc)
  90 {
  91         short vpi = vcc->vpi;
  92         int vci = vcc->vci;
  93
  94         if (vci == ATM_VCI_UNSPEC || vpi == ATM_VPI_UNSPEC)
  95                 return 0;
  96
  97         set_bit(ATM_VF_ADDR, &vcc->flags);
  98         set_bit(ATM_VF_READY, &vcc->flags);
  99
 100         return 0;
 101 }
 102
 103 static void
 104 adummy_close(struct atm_vcc *vcc)
 105 {
 106         clear_bit(ATM_VF_READY, &vcc->flags);
 107         clear_bit(ATM_VF_ADDR, &vcc->flags);
 108 }
 109
 110 static int
 111 adummy_send(struct atm_vcc *vcc, struct sk_buff *skb)
 112 {
 113         if (vcc->pop)
 114                 vcc->pop(vcc, skb);
 115         else
 116                 dev_kfree_skb_any(skb);
 117         atomic_inc(&vcc->stats->tx);
 118
 119         return 0;
 120 }
 121
 122 static int
 123 adummy_proc_read(struct atm_dev *dev, loff_t *pos, char *page)
 124 {
 125         int left = *pos;
 126
 127         if (!left--)
 128                 return sprintf(page, "version %s\n", DRV_VERSION);
 129
 130         return 0;
 131 }
 132
 133 static const struct atmdev_ops adummy_ops =
 134 {
 135         .open =         adummy_open,
 136         .close =        adummy_close,
 137         .send =         adummy_send,
 138         .proc_read =    adummy_proc_read,
 139         .owner =        THIS_MODULE
 140 };
 141
 142 static int __init adummy_init(void)
 143 {
 144         struct atm_dev *atm_dev;
 145         struct adummy_dev *adummy_dev;
 146         int err = 0;
 147
 148         printk(KERN_ERR "adummy: version %s\n", DRV_VERSION);
 149
 150         adummy_dev = kzalloc(sizeof(struct adummy_dev),
 151                                                    GFP_KERNEL);
 152         if (!adummy_dev) {
 153                 printk(KERN_ERR DEV_LABEL ": kzalloc() failed\n");
 154                 err = -ENOMEM;
 155                 goto out;
 156         }
 157         atm_dev = atm_dev_register(DEV_LABEL, NULL, &adummy_ops, -1, NULL);
 158         if (!atm_dev) {
 159                 printk(KERN_ERR DEV_LABEL ": atm_dev_register() failed\n");
 160                 err = -ENODEV;
 161                 goto out_kfree;
 162         }
 163
 164         adummy_dev->atm_dev = atm_dev;
 165         atm_dev->dev_data = adummy_dev;
 166
 167         if (sysfs_create_group(&atm_dev->class_dev.kobj, &adummy_group_attrs))
 168                 dev_err(&atm_dev->class_dev, "Could not register attrs for adummy\n");
 169
 170         if (adummy_start(atm_dev)) {
 171                 printk(KERN_ERR DEV_LABEL ": adummy_start() failed\n");
 172                 err = -ENODEV;
 173                 goto out_unregister;
 174         }
 175
 176         list_add(&adummy_dev->entry, &adummy_devs);
 177 out:
 178         return err;
 179
 180 out_unregister:
 181         atm_dev_deregister(atm_dev);
 182 out_kfree:
 183         kfree(adummy_dev);
 184         goto out;
 185 }
 186
 187 static void __exit adummy_cleanup(void)
 188 {
 189         struct adummy_dev *adummy_dev, *next;
 190
 191         list_for_each_entry_safe(adummy_dev, next, &adummy_devs, entry) {
 192                 atm_dev_deregister(adummy_dev->atm_dev);
 193                 kfree(adummy_dev);
 194         }
 195 }
 196
 197 module_init(adummy_init);
 198 module_exit(adummy_cleanup);
 199
 200 MODULE_AUTHOR("chas williams <chas@cmf.nrl.navy.mil>");
 201 MODULE_DESCRIPTION("dummy ATM driver");
 202 MODULE_LICENSE("GPL");