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
 33struct adummy_dev {
 34	struct atm_dev *atm_dev;
 35
 36	struct list_head entry;
 37};
 38
 39/* globals */
 40
 41static LIST_HEAD(adummy_devs);
 42
 43static 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
 61static 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}
 67static DEVICE_ATTR(signal, 0644, __show_signal, __set_signal);
 68
 69static struct attribute *adummy_attrs[] = {
 70	&dev_attr_signal.attr,
 71	NULL
 72};
 73
 74static struct attribute_group adummy_group_attrs = {
 75	.name = NULL, /* We want them in dev's root folder */
 76	.attrs = adummy_attrs
 77};
 78
 79static int __init
 80adummy_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
 88static int
 89adummy_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
103static void
104adummy_close(struct atm_vcc *vcc)
105{
106	clear_bit(ATM_VF_READY, &vcc->flags);
107	clear_bit(ATM_VF_ADDR, &vcc->flags);
108}
109
110static int
111adummy_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
122static int
123adummy_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
133static 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
142static 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);
177out:
178	return err;
179
180out_unregister:
181	atm_dev_deregister(atm_dev);
182out_kfree:
183	kfree(adummy_dev);
184	goto out;
185}
186
187static 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
197module_init(adummy_init);
198module_exit(adummy_cleanup);
199
200MODULE_AUTHOR("chas williams <chas@cmf.nrl.navy.mil>");
201MODULE_DESCRIPTION("dummy ATM driver");
202MODULE_LICENSE("GPL");