[PATCH] USB ATM: generic DSL modem driver xusbatm

/******************************************************************************

 *  xusbatm.c -	dumb usbatm-based driver for modems initialized in userspace

 *

 *  Copyright (C) 2005 Duncan Sands, Roman Kagan (rkagan % mail ! ru)

 *

 *  This program is free software; you can redistribute it and/or modify it

 *  under the terms of the GNU General Public License as published by the Free

 *  Software Foundation; either version 2 of the License, or (at your option)

 *  any later version.

 *

 *  This program is distributed in the hope that it will be useful, but WITHOUT

 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

 *  more details.

 *

 *  You should have received a copy of the GNU General Public License along with

 *  this program; if not, write to the Free Software Foundation, Inc., 59

 *  Temple Place - Suite 330, Boston, MA  02111-1307, USA.

 *

 ******************************************************************************/

#include <linux/module.h>

#include <linux/netdevice.h>		/* FIXME: required by linux/etherdevice.h */

#include <linux/etherdevice.h>		/* for random_ether_addr() */

#include "usbatm.h"

#define XUSBATM_DRIVERS_MAX	8

#define XUSBATM_PARM(name, type, parmtype, desc) \

	static type name[XUSBATM_DRIVERS_MAX]; \

	static int num_##name; \

	module_param_array(name, parmtype, &num_##name, 0444); \

	MODULE_PARM_DESC(name, desc)

XUSBATM_PARM(vendor, unsigned short, ushort, "USB device vendor");

XUSBATM_PARM(product, unsigned short, ushort, "USB device product");

XUSBATM_PARM(rx_endpoint, unsigned char, byte, "rx endpoint number");

XUSBATM_PARM(tx_endpoint, unsigned char, byte, "tx endpoint number");

XUSBATM_PARM(rx_padding, unsigned char, byte, "rx padding (default 0)");

XUSBATM_PARM(tx_padding, unsigned char, byte, "tx padding (default 0)");

static const char xusbatm_driver_name[] = "xusbatm";

static struct usbatm_driver xusbatm_drivers[XUSBATM_DRIVERS_MAX];

static struct usb_device_id xusbatm_usb_ids[XUSBATM_DRIVERS_MAX + 1];

static struct usb_driver xusbatm_usb_driver;

static int usb_intf_has_ep(const struct usb_interface *intf, u8 ep)

{

	int i, j;

	for (i = 0; i < intf->num_altsetting; i++) {

		struct usb_host_interface *alt = intf->altsetting;

		for (j = 0; j < alt->desc.bNumEndpoints; j++)

			if ((alt->endpoint[i].desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK) == ep)

				return 1;

	}

	return 0;

}

static int xusbatm_bind(struct usbatm_data *usbatm_instance,

			struct usb_interface *intf, const struct usb_device_id *id,

			int *need_heavy_init)

{

	struct usb_device *usb_dev = interface_to_usbdev(intf);

	int drv_ix = id - xusbatm_usb_ids;

	int rx_ep_present = usb_intf_has_ep(intf, rx_endpoint[drv_ix]);

	int tx_ep_present = usb_intf_has_ep(intf, tx_endpoint[drv_ix]);

	u8 searched_ep = rx_ep_present ? tx_endpoint[drv_ix] : rx_endpoint[drv_ix];

	int i, ret;

	usb_dbg(usbatm_instance, "%s: binding driver %d: vendor %#x product %#x"

		" rx: ep %#x padd %d tx: ep %#x padd %d\n",

		__func__, drv_ix, vendor[drv_ix], product[drv_ix],

		rx_endpoint[drv_ix], rx_padding[drv_ix],

		tx_endpoint[drv_ix], tx_padding[drv_ix]);

	if (!rx_ep_present && !tx_ep_present) {

		usb_dbg(usbatm_instance, "%s: intf #%d has neither rx (%#x) nor tx (%#x) endpoint\n",

			__func__, intf->altsetting->desc.bInterfaceNumber,

			rx_endpoint[drv_ix], tx_endpoint[drv_ix]);

		return -ENODEV;

	}

	if (rx_ep_present && tx_ep_present)

		return 0;

	for(i = 0; i < usb_dev->actconfig->desc.bNumInterfaces; i++) {

		struct usb_interface *cur_if = usb_dev->actconfig->interface[i];

		if (cur_if != intf && usb_intf_has_ep(cur_if, searched_ep)) {

			ret = usb_driver_claim_interface(&xusbatm_usb_driver,

							 cur_if, usbatm_instance);

			if (!ret)

				usb_err(usbatm_instance, "%s: failed to claim interface #%d (%d)\n",

					__func__, cur_if->altsetting->desc.bInterfaceNumber, ret);

			return ret;

		}

	}

	usb_err(usbatm_instance, "%s: no interface has endpoint %#x\n",

		__func__, searched_ep);

	return -ENODEV;

}

static void xusbatm_unbind(struct usbatm_data *usbatm_instance,

			   struct usb_interface *intf)

{

	struct usb_device *usb_dev = interface_to_usbdev(intf);

	int i;

	usb_dbg(usbatm_instance, "%s entered\n", __func__);

	for(i = 0; i < usb_dev->actconfig->desc.bNumInterfaces; i++) {

		struct usb_interface *cur_if = usb_dev->actconfig->interface[i];

		usb_set_intfdata(cur_if, NULL);

		usb_driver_release_interface(&xusbatm_usb_driver, cur_if);

	}

}

static int xusbatm_atm_start(struct usbatm_data *usbatm_instance,

			     struct atm_dev *atm_dev)

{

	atm_dbg(usbatm_instance, "%s entered\n", __func__);

	/* use random MAC as we've no way to get it from the device */

	random_ether_addr(atm_dev->esi);

	return 0;

}

static int xusbatm_usb_probe(struct usb_interface *intf,

			     const struct usb_device_id *id)

{

	return usbatm_usb_probe(intf, id,

				xusbatm_drivers + (id - xusbatm_usb_ids));

}

static struct usb_driver xusbatm_usb_driver = {

	.owner		= THIS_MODULE,

	.name		= xusbatm_driver_name,

	.probe		= xusbatm_usb_probe,

	.disconnect	= usbatm_usb_disconnect,

	.id_table	= xusbatm_usb_ids

};

static int __init xusbatm_init(void)

{

	int i;

	dbg("xusbatm_init");

	if (!num_vendor ||

	    num_vendor != num_product ||

	    num_vendor != num_rx_endpoint ||

	    num_vendor != num_tx_endpoint) {

		warn("malformed module parameters");

		return -EINVAL;

	}

	for (i = 0; i < num_vendor; i++) {

		xusbatm_usb_ids[i].match_flags	= USB_DEVICE_ID_MATCH_DEVICE;

		xusbatm_usb_ids[i].idVendor	= vendor[i];

		xusbatm_usb_ids[i].idProduct	= product[i];

		xusbatm_drivers[i].owner	= THIS_MODULE;

		xusbatm_drivers[i].driver_name	= xusbatm_driver_name;

		xusbatm_drivers[i].bind		= xusbatm_bind;

		xusbatm_drivers[i].unbind	= xusbatm_unbind;

		xusbatm_drivers[i].atm_start	= xusbatm_atm_start;

		xusbatm_drivers[i].in		= rx_endpoint[i];

		xusbatm_drivers[i].out		= tx_endpoint[i];

		xusbatm_drivers[i].rx_padding	= rx_padding[i];

		xusbatm_drivers[i].tx_padding	= tx_padding[i];

	}

	return usb_register(&xusbatm_usb_driver);

}

module_init(xusbatm_init);

static void __exit xusbatm_exit(void)

{

	dbg("xusbatm_exit entered");

	usb_deregister(&xusbatm_usb_driver);

}

module_exit(xusbatm_exit);

MODULE_AUTHOR("Roman Kagan, Duncan Sands");

MODULE_DESCRIPTION("Driver for USB ADSL modems initialized in userspace");

MODULE_LICENSE("GPL");

MODULE_VERSION("0.1");