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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * adummy.c: a dummy ATM driver4 */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 34struct adummy_dev {35 struct atm_dev *atm_dev;36 37 struct list_head entry;38};39 40/* globals */41 42static LIST_HEAD(adummy_devs);43 44static 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(atm_dev, signal);57 return 1;58 }59 return -EINVAL;60}61 62static 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, "%d\n", atm_dev->signal);67}68static DEVICE_ATTR(signal, 0644, __show_signal, __set_signal);69 70static struct attribute *adummy_attrs[] = {71 &dev_attr_signal.attr,72 NULL73};74 75static const struct attribute_group adummy_group_attrs = {76 .name = NULL, /* We want them in dev's root folder */77 .attrs = adummy_attrs78};79 80static int __init81adummy_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 89static int90adummy_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(ATM_VF_ADDR, &vcc->flags);99 set_bit(ATM_VF_READY, &vcc->flags);100 101 return 0;102}103 104static void105adummy_close(struct atm_vcc *vcc)106{107 clear_bit(ATM_VF_READY, &vcc->flags);108 clear_bit(ATM_VF_ADDR, &vcc->flags);109}110 111static int112adummy_send(struct atm_vcc *vcc, struct sk_buff *skb)113{114 if (vcc->pop)115 vcc->pop(vcc, skb);116 else117 dev_kfree_skb_any(skb);118 atomic_inc(&vcc->stats->tx);119 120 return 0;121}122 123static int124adummy_proc_read(struct atm_dev *dev, loff_t *pos, char *page)125{126 int left = *pos;127 128 if (!left--)129 return sprintf(page, "version %s\n", DRV_VERSION);130 131 return 0;132}133 134static 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_MODULE141};142 143static 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(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, &adummy_ops, -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(&atm_dev->class_dev.kobj, &adummy_group_attrs))169 dev_err(&atm_dev->class_dev, "Could not register attrs for adummy\n");170 171 if (adummy_start(atm_dev)) {172 printk(KERN_ERR DEV_LABEL ": adummy_start() failed\n");173 err = -ENODEV;174 goto out_unregister;175 }176 177 list_add(&adummy_dev->entry, &adummy_devs);178out:179 return err;180 181out_unregister:182 atm_dev_deregister(atm_dev);183out_kfree:184 kfree(adummy_dev);185 goto out;186}187 188static 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(adummy_dev->atm_dev);194 kfree(adummy_dev);195 }196}197 198module_init(adummy_init);199module_exit(adummy_cleanup);200 201MODULE_AUTHOR("chas williams <chas@cmf.nrl.navy.mil>");202MODULE_DESCRIPTION("dummy ATM driver");203MODULE_LICENSE("GPL");204