[ATM]: [adummy] dummy ATM driver (similar to net/dummy)

Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/atm/Kconfig

@@ -5,6 +5,13 @@
 menu "ATM drivers"
 	depends on NETDEVICES && ATM
 
+config ATM_DUMMY
+	tristate "Dummy ATM driver"
+	depends on ATM
+	help
+	  Dummy ATM driver. Useful for proxy signalling, testing,
+	  and development.  If unsure, say N.
+
 config ATM_TCP
 	tristate "ATM over TCP"
 	depends on INET && ATM

drivers/atm/Makefile

@@ -31,6 +31,7 @@ ifeq ($(CONFIG_ATM_IDT77252_USE_SUNI),y)
   obj-$(CONFIG_ATM_IDT77252)	+= suni.o
 endif
 
+obj-$(CONFIG_ATM_DUMMY)		+= adummy.o
 obj-$(CONFIG_ATM_TCP)		+= atmtcp.o
 obj-$(CONFIG_ATM_FIRESTREAM)	+= firestream.o
 obj-$(CONFIG_ATM_LANAI)		+= lanai.o

drivers/atm/adummy.c

@@ -0,0 +1,168 @@
+/*
+ * adummy.c: a dummy ATM driver
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/pci.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <asm/io.h>
+#include <asm/byteorder.h>
+#include <asm/uaccess.h>
+
+#include <linux/atmdev.h>
+#include <linux/atm.h>
+#include <linux/sonet.h>
+
+/* version definition */
+
+#define DRV_VERSION "1.0"
+
+#define DEV_LABEL "adummy"
+
+#define ADUMMY_DEV(dev) ((struct adummy_dev *) (dev)->dev_data)
+
+struct adummy_dev {
+	struct atm_dev *atm_dev;
+
+	struct list_head entry;
+};
+
+/* globals */
+
+static LIST_HEAD(adummy_devs);
+
+static int __init
+adummy_start(struct atm_dev *dev)
+{
+	dev->ci_range.vpi_bits = 4;
+	dev->ci_range.vci_bits = 12;
+
+	return 0;
+}
+
+static int
+adummy_open(struct atm_vcc *vcc)
+{
+	short vpi = vcc->vpi;
+	int vci = vcc->vci;
+
+	if (vci == ATM_VCI_UNSPEC || vpi == ATM_VPI_UNSPEC)
+		return 0;
+
+	set_bit(ATM_VF_ADDR, &vcc->flags);
+	set_bit(ATM_VF_READY, &vcc->flags);
+
+	return 0;
+}
+
+static void
+adummy_close(struct atm_vcc *vcc)
+{
+	clear_bit(ATM_VF_READY, &vcc->flags);
+	clear_bit(ATM_VF_ADDR, &vcc->flags);
+}
+
+static int
+adummy_send(struct atm_vcc *vcc, struct sk_buff *skb)
+{
+	if (vcc->pop)
+		vcc->pop(vcc, skb);
+	else
+		dev_kfree_skb_any(skb);
+	atomic_inc(&vcc->stats->tx);
+
+	return 0;
+}
+
+static int
+adummy_proc_read(struct atm_dev *dev, loff_t *pos, char *page)
+{
+	int left = *pos;
+
+	if (!left--)
+		return sprintf(page, "version %s\n", DRV_VERSION);
+
+	return 0;
+}
+
+static struct atmdev_ops adummy_ops =
+{
+	.open =		adummy_open,
+	.close =	adummy_close,	
+	.send =		adummy_send,
+	.proc_read =	adummy_proc_read,
+	.owner =	THIS_MODULE
+};
+
+static int __init adummy_init(void)
+{
+	struct atm_dev *atm_dev;
+	struct adummy_dev *adummy_dev;
+	int err = 0;
+
+	printk(KERN_ERR "adummy: version %s\n", DRV_VERSION);
+
+	adummy_dev = (struct adummy_dev *) kmalloc(sizeof(struct adummy_dev),
+						   GFP_KERNEL);
+	if (!adummy_dev) {
+		printk(KERN_ERR DEV_LABEL ": kmalloc() failed\n");
+		err = -ENOMEM;
+		goto out;
+	}
+	memset(adummy_dev, 0, sizeof(struct adummy_dev));
+
+	atm_dev = atm_dev_register(DEV_LABEL, &adummy_ops, -1, 0);
+	if (!atm_dev) {
+		printk(KERN_ERR DEV_LABEL ": atm_dev_register() failed\n");
+		err = -ENODEV;
+		goto out_kfree;
+	}
+
+	adummy_dev->atm_dev = atm_dev;
+	atm_dev->dev_data = adummy_dev;
+
+	if (adummy_start(atm_dev)) {
+		printk(KERN_ERR DEV_LABEL ": adummy_start() failed\n");
+		err = -ENODEV;
+		goto out_unregister;
+	}
+
+	list_add(&adummy_dev->entry, &adummy_devs);
+out:
+	return err;
+
+out_unregister:
+	atm_dev_deregister(atm_dev);
+out_kfree:
+	kfree(adummy_dev);
+	goto out;
+}
+
+static void __exit adummy_cleanup(void)
+{
+	struct adummy_dev *adummy_dev, *next;
+
+	list_for_each_entry_safe(adummy_dev, next, &adummy_devs, entry) {
+		atm_dev_deregister(adummy_dev->atm_dev);
+		kfree(adummy_dev);
+	}
+}
+
+module_init(adummy_init);
+module_exit(adummy_cleanup);
+
+MODULE_AUTHOR("chas williams <chas@cmf.nrl.navy.mil>");
+MODULE_DESCRIPTION("dummy ATM driver");
+MODULE_LICENSE("GPL");