1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * adummy.c: a dummy ATM driver |
4 | */ |
5 | |
6 | #include <linux/module.h> |
7 | #include <linux/kernel.h> |
8 | #include <linux/skbuff.h> |
9 | #include <linux/errno.h> |
10 | #include <linux/types.h> |
11 | #include <linux/string.h> |
12 | #include <linux/delay.h> |
13 | #include <linux/init.h> |
14 | #include <linux/mm.h> |
15 | #include <linux/timer.h> |
16 | #include <linux/interrupt.h> |
17 | #include <linux/slab.h> |
18 | #include <asm/io.h> |
19 | #include <asm/byteorder.h> |
20 | #include <linux/uaccess.h> |
21 | |
22 | #include <linux/atmdev.h> |
23 | #include <linux/atm.h> |
24 | #include <linux/sonet.h> |
25 | |
26 | /* version definition */ |
27 | |
28 | #define DRV_VERSION "1.0" |
29 | |
30 | #define DEV_LABEL "adummy" |
31 | |
32 | #define ADUMMY_DEV(dev) ((struct adummy_dev *) (dev)->dev_data) |
33 | |
34 | struct adummy_dev { |
35 | struct atm_dev *atm_dev; |
36 | |
37 | struct list_head entry; |
38 | }; |
39 | |
40 | /* globals */ |
41 | |
42 | static LIST_HEAD(adummy_devs); |
43 | |
44 | static ssize_t __set_signal(struct device *dev, |
45 | struct device_attribute *attr, |
46 | const char *buf, size_t len) |
47 | { |
48 | struct atm_dev *atm_dev = container_of(dev, struct atm_dev, class_dev); |
49 | int signal; |
50 | |
51 | if (sscanf(buf, "%d" , &signal) == 1) { |
52 | |
53 | if (signal < ATM_PHY_SIG_LOST || signal > ATM_PHY_SIG_FOUND) |
54 | signal = ATM_PHY_SIG_UNKNOWN; |
55 | |
56 | atm_dev_signal_change(dev: atm_dev, signal); |
57 | return 1; |
58 | } |
59 | return -EINVAL; |
60 | } |
61 | |
62 | static ssize_t __show_signal(struct device *dev, |
63 | struct device_attribute *attr, char *buf) |
64 | { |
65 | struct atm_dev *atm_dev = container_of(dev, struct atm_dev, class_dev); |
66 | return sprintf(buf, fmt: "%d\n" , atm_dev->signal); |
67 | } |
68 | static DEVICE_ATTR(signal, 0644, __show_signal, __set_signal); |
69 | |
70 | static struct attribute *adummy_attrs[] = { |
71 | &dev_attr_signal.attr, |
72 | NULL |
73 | }; |
74 | |
75 | static const struct attribute_group adummy_group_attrs = { |
76 | .name = NULL, /* We want them in dev's root folder */ |
77 | .attrs = adummy_attrs |
78 | }; |
79 | |
80 | static int __init |
81 | adummy_start(struct atm_dev *dev) |
82 | { |
83 | dev->ci_range.vpi_bits = 4; |
84 | dev->ci_range.vci_bits = 12; |
85 | |
86 | return 0; |
87 | } |
88 | |
89 | static int |
90 | adummy_open(struct atm_vcc *vcc) |
91 | { |
92 | short vpi = vcc->vpi; |
93 | int vci = vcc->vci; |
94 | |
95 | if (vci == ATM_VCI_UNSPEC || vpi == ATM_VPI_UNSPEC) |
96 | return 0; |
97 | |
98 | set_bit(nr: ATM_VF_ADDR, addr: &vcc->flags); |
99 | set_bit(nr: ATM_VF_READY, addr: &vcc->flags); |
100 | |
101 | return 0; |
102 | } |
103 | |
104 | static void |
105 | adummy_close(struct atm_vcc *vcc) |
106 | { |
107 | clear_bit(nr: ATM_VF_READY, addr: &vcc->flags); |
108 | clear_bit(nr: ATM_VF_ADDR, addr: &vcc->flags); |
109 | } |
110 | |
111 | static int |
112 | adummy_send(struct atm_vcc *vcc, struct sk_buff *skb) |
113 | { |
114 | if (vcc->pop) |
115 | vcc->pop(vcc, skb); |
116 | else |
117 | dev_kfree_skb_any(skb); |
118 | atomic_inc(v: &vcc->stats->tx); |
119 | |
120 | return 0; |
121 | } |
122 | |
123 | static int |
124 | adummy_proc_read(struct atm_dev *dev, loff_t *pos, char *page) |
125 | { |
126 | int left = *pos; |
127 | |
128 | if (!left--) |
129 | return sprintf(buf: page, fmt: "version %s\n" , DRV_VERSION); |
130 | |
131 | return 0; |
132 | } |
133 | |
134 | static const struct atmdev_ops adummy_ops = |
135 | { |
136 | .open = adummy_open, |
137 | .close = adummy_close, |
138 | .send = adummy_send, |
139 | .proc_read = adummy_proc_read, |
140 | .owner = THIS_MODULE |
141 | }; |
142 | |
143 | static int __init adummy_init(void) |
144 | { |
145 | struct atm_dev *atm_dev; |
146 | struct adummy_dev *adummy_dev; |
147 | int err = 0; |
148 | |
149 | printk(KERN_ERR "adummy: version %s\n" , DRV_VERSION); |
150 | |
151 | adummy_dev = kzalloc(size: sizeof(struct adummy_dev), |
152 | GFP_KERNEL); |
153 | if (!adummy_dev) { |
154 | printk(KERN_ERR DEV_LABEL ": kzalloc() failed\n" ); |
155 | err = -ENOMEM; |
156 | goto out; |
157 | } |
158 | atm_dev = atm_dev_register(DEV_LABEL, NULL, ops: &adummy_ops, number: -1, NULL); |
159 | if (!atm_dev) { |
160 | printk(KERN_ERR DEV_LABEL ": atm_dev_register() failed\n" ); |
161 | err = -ENODEV; |
162 | goto out_kfree; |
163 | } |
164 | |
165 | adummy_dev->atm_dev = atm_dev; |
166 | atm_dev->dev_data = adummy_dev; |
167 | |
168 | if (sysfs_create_group(kobj: &atm_dev->class_dev.kobj, grp: &adummy_group_attrs)) |
169 | dev_err(&atm_dev->class_dev, "Could not register attrs for adummy\n" ); |
170 | |
171 | if (adummy_start(dev: atm_dev)) { |
172 | printk(KERN_ERR DEV_LABEL ": adummy_start() failed\n" ); |
173 | err = -ENODEV; |
174 | goto out_unregister; |
175 | } |
176 | |
177 | list_add(new: &adummy_dev->entry, head: &adummy_devs); |
178 | out: |
179 | return err; |
180 | |
181 | out_unregister: |
182 | atm_dev_deregister(dev: atm_dev); |
183 | out_kfree: |
184 | kfree(objp: adummy_dev); |
185 | goto out; |
186 | } |
187 | |
188 | static void __exit adummy_cleanup(void) |
189 | { |
190 | struct adummy_dev *adummy_dev, *next; |
191 | |
192 | list_for_each_entry_safe(adummy_dev, next, &adummy_devs, entry) { |
193 | atm_dev_deregister(dev: adummy_dev->atm_dev); |
194 | kfree(objp: adummy_dev); |
195 | } |
196 | } |
197 | |
198 | module_init(adummy_init); |
199 | module_exit(adummy_cleanup); |
200 | |
201 | MODULE_AUTHOR("chas williams <chas@cmf.nrl.navy.mil>" ); |
202 | MODULE_DESCRIPTION("dummy ATM driver" ); |
203 | MODULE_LICENSE("GPL" ); |
204 | |