Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1188 insertions, 0 deletions

diff --git a/drivers/usb/atm/usb_atm.c b/drivers/usb/atm/usb_atm.c
new file mode 100644
index 00000000000..a4cd4476d49
--- /dev/null
+++ b/drivers/usb/atm/usb_atm.c
@@ -0,0 +1,1188 @@
+/******************************************************************************
+ *  usb_atm.c - Generic USB xDSL driver core
+ *
+ *  Copyright (C) 2001, Alcatel
+ *  Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas
+ *  Copyright (C) 2004, David Woodhouse
+ *
+ *  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.
+ *
+ ******************************************************************************/
+
+/*
+ *  Written by Johan Verrept, maintained by Duncan Sands (duncan.sands@free.fr)
+ *
+ *  1.7+:	- See the check-in logs
+ *
+ *  1.6:	- No longer opens a connection if the firmware is not loaded
+ *  		- Added support for the speedtouch 330
+ *  		- Removed the limit on the number of devices
+ *  		- Module now autoloads on device plugin
+ *  		- Merged relevant parts of sarlib
+ *  		- Replaced the kernel thread with a tasklet
+ *  		- New packet transmission code
+ *  		- Changed proc file contents
+ *  		- Fixed all known SMP races
+ *  		- Many fixes and cleanups
+ *  		- Various fixes by Oliver Neukum (oliver@neukum.name)
+ *
+ *  1.5A:	- Version for inclusion in 2.5 series kernel
+ *		- Modifications by Richard Purdie (rpurdie@rpsys.net)
+ *		- made compatible with kernel 2.5.6 onwards by changing
+ *		udsl_usb_send_data_context->urb to a pointer and adding code
+ *		to alloc and free it
+ *		- remove_wait_queue() added to udsl_atm_processqueue_thread()
+ *
+ *  1.5:	- fixed memory leak when atmsar_decode_aal5 returned NULL.
+ *		(reported by stephen.robinson@zen.co.uk)
+ *
+ *  1.4:	- changed the spin_lock() under interrupt to spin_lock_irqsave()
+ *		- unlink all active send urbs of a vcc that is being closed.
+ *
+ *  1.3.1:	- added the version number
+ *
+ *  1.3:	- Added multiple send urb support
+ *		- fixed memory leak and vcc->tx_inuse starvation bug
+ *		  when not enough memory left in vcc.
+ *
+ *  1.2:	- Fixed race condition in udsl_usb_send_data()
+ *  1.1:	- Turned off packet debugging
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/errno.h>
+#include <linux/proc_fs.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/list.h>
+#include <asm/uaccess.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/atm.h>
+#include <linux/atmdev.h>
+#include <linux/crc32.h>
+#include <linux/init.h>
+#include <linux/firmware.h>
+
+#include "usb_atm.h"
+
+#ifdef VERBOSE_DEBUG
+static int udsl_print_packet(const unsigned char *data, int len);
+#define PACKETDEBUG(arg...)	udsl_print_packet (arg)
+#define vdbg(arg...)		dbg (arg)
+#else
+#define PACKETDEBUG(arg...)
+#define vdbg(arg...)
+#endif
+
+#define DRIVER_AUTHOR	"Johan Verrept, Duncan Sands <duncan.sands@free.fr>"
+#define DRIVER_VERSION	"1.8"
+#define DRIVER_DESC	"Generic USB ATM/DSL I/O, version " DRIVER_VERSION
+
+static unsigned int num_rcv_urbs = UDSL_DEFAULT_RCV_URBS;
+static unsigned int num_snd_urbs = UDSL_DEFAULT_SND_URBS;
+static unsigned int num_rcv_bufs = UDSL_DEFAULT_RCV_BUFS;
+static unsigned int num_snd_bufs = UDSL_DEFAULT_SND_BUFS;
+static unsigned int rcv_buf_size = UDSL_DEFAULT_RCV_BUF_SIZE;
+static unsigned int snd_buf_size = UDSL_DEFAULT_SND_BUF_SIZE;
+
+module_param(num_rcv_urbs, uint, 0444);
+MODULE_PARM_DESC(num_rcv_urbs,
+		 "Number of urbs used for reception (range: 0-"
+		 __MODULE_STRING(UDSL_MAX_RCV_URBS) ", default: "
+		 __MODULE_STRING(UDSL_DEFAULT_RCV_URBS) ")");
+
+module_param(num_snd_urbs, uint, 0444);
+MODULE_PARM_DESC(num_snd_urbs,
+		 "Number of urbs used for transmission (range: 0-"
+		 __MODULE_STRING(UDSL_MAX_SND_URBS) ", default: "
+		 __MODULE_STRING(UDSL_DEFAULT_SND_URBS) ")");
+
+module_param(num_rcv_bufs, uint, 0444);
+MODULE_PARM_DESC(num_rcv_bufs,
+		 "Number of buffers used for reception (range: 0-"
+		 __MODULE_STRING(UDSL_MAX_RCV_BUFS) ", default: "
+		 __MODULE_STRING(UDSL_DEFAULT_RCV_BUFS) ")");
+
+module_param(num_snd_bufs, uint, 0444);
+MODULE_PARM_DESC(num_snd_bufs,
+		 "Number of buffers used for transmission (range: 0-"
+		 __MODULE_STRING(UDSL_MAX_SND_BUFS) ", default: "
+		 __MODULE_STRING(UDSL_DEFAULT_SND_BUFS) ")");
+
+module_param(rcv_buf_size, uint, 0444);
+MODULE_PARM_DESC(rcv_buf_size,
+		 "Size of the buffers used for reception (range: 0-"
+		 __MODULE_STRING(UDSL_MAX_RCV_BUF_SIZE) ", default: "
+		 __MODULE_STRING(UDSL_DEFAULT_RCV_BUF_SIZE) ")");
+
+module_param(snd_buf_size, uint, 0444);
+MODULE_PARM_DESC(snd_buf_size,
+		 "Size of the buffers used for transmission (range: 0-"
+		 __MODULE_STRING(UDSL_MAX_SND_BUF_SIZE) ", default: "
+		 __MODULE_STRING(UDSL_DEFAULT_SND_BUF_SIZE) ")");
+
+/* ATM */
+
+static void udsl_atm_dev_close(struct atm_dev *dev);
+static int udsl_atm_open(struct atm_vcc *vcc);
+static void udsl_atm_close(struct atm_vcc *vcc);
+static int udsl_atm_ioctl(struct atm_dev *dev, unsigned int cmd, void __user * arg);
+static int udsl_atm_send(struct atm_vcc *vcc, struct sk_buff *skb);
+static int udsl_atm_proc_read(struct atm_dev *atm_dev, loff_t * pos, char *page);
+
+static struct atmdev_ops udsl_atm_devops = {
+	.dev_close	= udsl_atm_dev_close,
+	.open		= udsl_atm_open,
+	.close		= udsl_atm_close,
+	.ioctl		= udsl_atm_ioctl,
+	.send		= udsl_atm_send,
+	.proc_read	= udsl_atm_proc_read,
+	.owner		= THIS_MODULE,
+};
+
+/***********
+**  misc  **
+***********/
+
+static inline void udsl_pop(struct atm_vcc *vcc, struct sk_buff *skb)
+{
+	if (vcc->pop)
+		vcc->pop(vcc, skb);
+	else
+		dev_kfree_skb(skb);
+}
+
+/*************
+**  decode  **
+*************/
+
+static inline struct udsl_vcc_data *udsl_find_vcc(struct udsl_instance_data *instance,
+						  short vpi, int vci)
+{
+	struct udsl_vcc_data *vcc;
+
+	list_for_each_entry(vcc, &instance->vcc_list, list)
+		if ((vcc->vci == vci) && (vcc->vpi == vpi))
+			return vcc;
+	return NULL;
+}
+
+static void udsl_extract_cells(struct udsl_instance_data *instance,
+			       unsigned char *source, unsigned int howmany)
+{
+	struct udsl_vcc_data *cached_vcc = NULL;
+	struct atm_vcc *vcc;
+	struct sk_buff *sarb;
+	struct udsl_vcc_data *vcc_data;
+	int cached_vci = 0;
+	unsigned int i;
+	int pti;
+	int vci;
+	short cached_vpi = 0;
+	short vpi;
+
+	for (i = 0; i < howmany;
+	     i++, source += ATM_CELL_SIZE + instance->rcv_padding) {
+		vpi = ((source[0] & 0x0f) << 4) | (source[1] >> 4);
+		vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) | (source[3] >> 4);
+		pti = (source[3] & 0x2) != 0;
+
+		vdbg("udsl_extract_cells: vpi %hd, vci %d, pti %d", vpi, vci, pti);
+
+		if (cached_vcc && (vci == cached_vci) && (vpi == cached_vpi))
+			vcc_data = cached_vcc;
+		else if ((vcc_data = udsl_find_vcc(instance, vpi, vci))) {
+			cached_vcc = vcc_data;
+			cached_vpi = vpi;
+			cached_vci = vci;
+		} else {
+			dbg("udsl_extract_cells: unknown vpi/vci (%hd/%d)!", vpi, vci);
+			continue;
+		}
+
+		vcc = vcc_data->vcc;
+		sarb = vcc_data->sarb;
+
+		if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) {
+			dbg("udsl_extract_cells: buffer overrun (sarb->len %u, vcc: 0x%p)!", sarb->len, vcc);
+			/* discard cells already received */
+			skb_trim(sarb, 0);
+		}
+
+		memcpy(sarb->tail, source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD);
+		__skb_put(sarb, ATM_CELL_PAYLOAD);
+
+		if (pti) {
+			struct sk_buff *skb;
+			unsigned int length;
+			unsigned int pdu_length;
+
+			length = (source[ATM_CELL_SIZE - 6] << 8) + source[ATM_CELL_SIZE - 5];
+
+			/* guard against overflow */
+			if (length > ATM_MAX_AAL5_PDU) {
+				dbg("udsl_extract_cells: bogus length %u (vcc: 0x%p)!", length, vcc);
+				atomic_inc(&vcc->stats->rx_err);
+				goto out;
+			}
+
+			pdu_length = UDSL_NUM_CELLS(length) * ATM_CELL_PAYLOAD;
+
+			if (sarb->len < pdu_length) {
+				dbg("udsl_extract_cells: bogus pdu_length %u (sarb->len: %u, vcc: 0x%p)!", pdu_length, sarb->len, vcc);
+				atomic_inc(&vcc->stats->rx_err);
+				goto out;
+			}
+
+			if (crc32_be(~0, sarb->tail - pdu_length, pdu_length) != 0xc704dd7b) {
+				dbg("udsl_extract_cells: packet failed crc check (vcc: 0x%p)!", vcc);
+				atomic_inc(&vcc->stats->rx_err);
+				goto out;
+			}
+
+			vdbg("udsl_extract_cells: got packet (length: %u, pdu_length: %u, vcc: 0x%p)", length, pdu_length, vcc);
+
+			if (!(skb = dev_alloc_skb(length))) {
+				dbg("udsl_extract_cells: no memory for skb (length: %u)!", length);
+				atomic_inc(&vcc->stats->rx_drop);
+				goto out;
+			}
+
+			vdbg("udsl_extract_cells: allocated new sk_buff (skb: 0x%p, skb->truesize: %u)", skb, skb->truesize);
+
+			if (!atm_charge(vcc, skb->truesize)) {
+				dbg("udsl_extract_cells: failed atm_charge (skb->truesize: %u)!", skb->truesize);
+				dev_kfree_skb(skb);
+				goto out;	/* atm_charge increments rx_drop */
+			}
+
+			memcpy(skb->data, sarb->tail - pdu_length, length);
+			__skb_put(skb, length);
+
+			vdbg("udsl_extract_cells: sending skb 0x%p, skb->len %u, skb->truesize %u", skb, skb->len, skb->truesize);
+
+			PACKETDEBUG(skb->data, skb->len);
+
+			vcc->push(vcc, skb);
+
+			atomic_inc(&vcc->stats->rx);
+		out:
+			skb_trim(sarb, 0);
+		}
+	}
+}
+
+/*************
+**  encode  **
+*************/
+
+static inline void udsl_fill_cell_header(unsigned char *target, struct atm_vcc *vcc)
+{
+	target[0] = vcc->vpi >> 4;
+	target[1] = (vcc->vpi << 4) | (vcc->vci >> 12);
+	target[2] = vcc->vci >> 4;
+	target[3] = vcc->vci << 4;
+	target[4] = 0xec;
+}
+
+static const unsigned char zeros[ATM_CELL_PAYLOAD];
+
+static void udsl_groom_skb(struct atm_vcc *vcc, struct sk_buff *skb)
+{
+	struct udsl_control *ctrl = UDSL_SKB(skb);
+	unsigned int zero_padding;
+	u32 crc;
+
+	ctrl->atm_data.vcc = vcc;
+
+	ctrl->num_cells = UDSL_NUM_CELLS(skb->len);
+	ctrl->num_entire = skb->len / ATM_CELL_PAYLOAD;
+
+	zero_padding = ctrl->num_cells * ATM_CELL_PAYLOAD - skb->len - ATM_AAL5_TRAILER;
+
+	if (ctrl->num_entire + 1 < ctrl->num_cells)
+		ctrl->pdu_padding = zero_padding - (ATM_CELL_PAYLOAD - ATM_AAL5_TRAILER);
+	else
+		ctrl->pdu_padding = zero_padding;
+
+	ctrl->aal5_trailer[0] = 0;	/* UU = 0 */
+	ctrl->aal5_trailer[1] = 0;	/* CPI = 0 */
+	ctrl->aal5_trailer[2] = skb->len >> 8;
+	ctrl->aal5_trailer[3] = skb->len;
+
+	crc = crc32_be(~0, skb->data, skb->len);
+	crc = crc32_be(crc, zeros, zero_padding);
+	crc = crc32_be(crc, ctrl->aal5_trailer, 4);
+	crc = ~crc;
+
+	ctrl->aal5_trailer[4] = crc >> 24;
+	ctrl->aal5_trailer[5] = crc >> 16;
+	ctrl->aal5_trailer[6] = crc >> 8;
+	ctrl->aal5_trailer[7] = crc;
+}
+
+static unsigned int udsl_write_cells(struct udsl_instance_data *instance,
+				     unsigned int howmany, struct sk_buff *skb,
+				     unsigned char **target_p)
+{
+	struct udsl_control *ctrl = UDSL_SKB(skb);
+	unsigned char *target = *target_p;
+	unsigned int nc, ne, i;
+
+	vdbg("udsl_write_cells: howmany=%u, skb->len=%d, num_cells=%u, num_entire=%u, pdu_padding=%u", howmany, skb->len, ctrl->num_cells, ctrl->num_entire, ctrl->pdu_padding);
+
+	nc = ctrl->num_cells;
+	ne = min(howmany, ctrl->num_entire);
+
+	for (i = 0; i < ne; i++) {
+		udsl_fill_cell_header(target, ctrl->atm_data.vcc);
+		target += ATM_CELL_HEADER;
+		memcpy(target, skb->data, ATM_CELL_PAYLOAD);
+		target += ATM_CELL_PAYLOAD;
+		if (instance->snd_padding) {
+			memset(target, 0, instance->snd_padding);
+			target += instance->snd_padding;
+		}
+		__skb_pull(skb, ATM_CELL_PAYLOAD);
+	}
+
+	ctrl->num_entire -= ne;
+
+	if (!(ctrl->num_cells -= ne) || !(howmany -= ne))
+		goto out;
+
+	udsl_fill_cell_header(target, ctrl->atm_data.vcc);
+	target += ATM_CELL_HEADER;
+	memcpy(target, skb->data, skb->len);
+	target += skb->len;
+	__skb_pull(skb, skb->len);
+	memset(target, 0, ctrl->pdu_padding);
+	target += ctrl->pdu_padding;
+
+	if (--ctrl->num_cells) {
+		if (!--howmany) {
+			ctrl->pdu_padding = ATM_CELL_PAYLOAD - ATM_AAL5_TRAILER;
+			goto out;
+		}
+
+		if (instance->snd_padding) {
+			memset(target, 0, instance->snd_padding);
+			target += instance->snd_padding;
+		}
+		udsl_fill_cell_header(target, ctrl->atm_data.vcc);
+		target += ATM_CELL_HEADER;
+		memset(target, 0, ATM_CELL_PAYLOAD - ATM_AAL5_TRAILER);
+		target += ATM_CELL_PAYLOAD - ATM_AAL5_TRAILER;
+
+		--ctrl->num_cells;
+		UDSL_ASSERT(!ctrl->num_cells);
+	}
+
+	memcpy(target, ctrl->aal5_trailer, ATM_AAL5_TRAILER);
+	target += ATM_AAL5_TRAILER;
+	/* set pti bit in last cell */
+	*(target + 3 - ATM_CELL_SIZE) |= 0x2;
+	if (instance->snd_padding) {
+		memset(target, 0, instance->snd_padding);
+		target += instance->snd_padding;
+	}
+ out:
+	*target_p = target;
+	return nc - ctrl->num_cells;
+}
+
+/**************
+**  receive  **
+**************/
+
+static void udsl_complete_receive(struct urb *urb, struct pt_regs *regs)
+{
+	struct udsl_receive_buffer *buf;
+	struct udsl_instance_data *instance;
+	struct udsl_receiver *rcv;
+	unsigned long flags;
+
+	if (!urb || !(rcv = urb->context)) {
+		dbg("udsl_complete_receive: bad urb!");
+		return;
+	}
+
+	instance = rcv->instance;
+	buf = rcv->buffer;
+
+	buf->filled_cells = urb->actual_length / (ATM_CELL_SIZE + instance->rcv_padding);
+
+	vdbg("udsl_complete_receive: urb 0x%p, status %d, actual_length %d, filled_cells %u, rcv 0x%p, buf 0x%p", urb, urb->status, urb->actual_length, buf->filled_cells, rcv, buf);
+
+	UDSL_ASSERT(buf->filled_cells <= rcv_buf_size);
+
+	/* may not be in_interrupt() */
+	spin_lock_irqsave(&instance->receive_lock, flags);
+	list_add(&rcv->list, &instance->spare_receivers);
+	list_add_tail(&buf->list, &instance->filled_receive_buffers);
+	if (likely(!urb->status))
+		tasklet_schedule(&instance->receive_tasklet);
+	spin_unlock_irqrestore(&instance->receive_lock, flags);
+}
+
+static void udsl_process_receive(unsigned long data)
+{
+	struct udsl_receive_buffer *buf;
+	struct udsl_instance_data *instance = (struct udsl_instance_data *)data;
+	struct udsl_receiver *rcv;
+	int err;
+
+ made_progress:
+	while (!list_empty(&instance->spare_receive_buffers)) {
+		spin_lock_irq(&instance->receive_lock);
+		if (list_empty(&instance->spare_receivers)) {
+			spin_unlock_irq(&instance->receive_lock);
+			break;
+		}
+		rcv = list_entry(instance->spare_receivers.next,
+				 struct udsl_receiver, list);
+		list_del(&rcv->list);
+		spin_unlock_irq(&instance->receive_lock);
+
+		buf = list_entry(instance->spare_receive_buffers.next,
+				 struct udsl_receive_buffer, list);
+		list_del(&buf->list);
+
+		rcv->buffer = buf;
+
+		usb_fill_bulk_urb(rcv->urb, instance->usb_dev,
+				  usb_rcvbulkpipe(instance->usb_dev, instance->data_endpoint),
+				  buf->base,
+				  rcv_buf_size * (ATM_CELL_SIZE + instance->rcv_padding),
+				  udsl_complete_receive, rcv);
+
+		vdbg("udsl_process_receive: sending urb 0x%p, rcv 0x%p, buf 0x%p",
+		     rcv->urb, rcv, buf);
+
+		if ((err = usb_submit_urb(rcv->urb, GFP_ATOMIC)) < 0) {
+			dbg("udsl_process_receive: urb submission failed (%d)!", err);
+			list_add(&buf->list, &instance->spare_receive_buffers);
+			spin_lock_irq(&instance->receive_lock);
+			list_add(&rcv->list, &instance->spare_receivers);
+			spin_unlock_irq(&instance->receive_lock);
+			break;
+		}
+	}
+
+	spin_lock_irq(&instance->receive_lock);
+	if (list_empty(&instance->filled_receive_buffers)) {
+		spin_unlock_irq(&instance->receive_lock);
+		return;		/* done - no more buffers */
+	}
+	buf = list_entry(instance->filled_receive_buffers.next,
+			 struct udsl_receive_buffer, list);
+	list_del(&buf->list);
+	spin_unlock_irq(&instance->receive_lock);
+
+	vdbg("udsl_process_receive: processing buf 0x%p", buf);
+	udsl_extract_cells(instance, buf->base, buf->filled_cells);
+	list_add(&buf->list, &instance->spare_receive_buffers);
+	goto made_progress;
+}
+
+/***********
+**  send  **
+***********/
+
+static void udsl_complete_send(struct urb *urb, struct pt_regs *regs)
+{
+	struct udsl_instance_data *instance;
+	struct udsl_sender *snd;
+	unsigned long flags;
+
+	if (!urb || !(snd = urb->context) || !(instance = snd->instance)) {
+		dbg("udsl_complete_send: bad urb!");
+		return;
+	}
+
+	vdbg("udsl_complete_send: urb 0x%p, status %d, snd 0x%p, buf 0x%p", urb,
+	     urb->status, snd, snd->buffer);
+
+	/* may not be in_interrupt() */
+	spin_lock_irqsave(&instance->send_lock, flags);
+	list_add(&snd->list, &instance->spare_senders);
+	list_add(&snd->buffer->list, &instance->spare_send_buffers);
+	tasklet_schedule(&instance->send_tasklet);
+	spin_unlock_irqrestore(&instance->send_lock, flags);
+}
+
+static void udsl_process_send(unsigned long data)
+{
+	struct udsl_send_buffer *buf;
+	struct udsl_instance_data *instance = (struct udsl_instance_data *)data;
+	struct sk_buff *skb;
+	struct udsl_sender *snd;
+	int err;
+	unsigned int num_written;
+
+ made_progress:
+	spin_lock_irq(&instance->send_lock);
+	while (!list_empty(&instance->spare_senders)) {
+		if (!list_empty(&instance->filled_send_buffers)) {
+			buf = list_entry(instance->filled_send_buffers.next,
+					 struct udsl_send_buffer, list);
+			list_del(&buf->list);
+		} else if ((buf = instance->current_buffer)) {
+			instance->current_buffer = NULL;
+		} else		/* all buffers empty */
+			break;
+
+		snd = list_entry(instance->spare_senders.next,
+				 struct udsl_sender, list);
+		list_del(&snd->list);
+		spin_unlock_irq(&instance->send_lock);
+
+		snd->buffer = buf;
+		usb_fill_bulk_urb(snd->urb, instance->usb_dev,
+				  usb_sndbulkpipe(instance->usb_dev, instance->data_endpoint),
+				  buf->base,
+				  (snd_buf_size - buf->free_cells) * (ATM_CELL_SIZE + instance->snd_padding),
+				  udsl_complete_send, snd);
+
+		vdbg("udsl_process_send: submitting urb 0x%p (%d cells), snd 0x%p, buf 0x%p",
+		     snd->urb, snd_buf_size - buf->free_cells, snd, buf);
+
+		if ((err = usb_submit_urb(snd->urb, GFP_ATOMIC)) < 0) {
+			dbg("udsl_process_send: urb submission failed (%d)!", err);
+			spin_lock_irq(&instance->send_lock);
+			list_add(&snd->list, &instance->spare_senders);
+			spin_unlock_irq(&instance->send_lock);
+			list_add(&buf->list, &instance->filled_send_buffers);
+			return;	/* bail out */
+		}
+
+		spin_lock_irq(&instance->send_lock);
+	}			/* while */
+	spin_unlock_irq(&instance->send_lock);
+
+	if (!instance->current_skb)
+		instance->current_skb = skb_dequeue(&instance->sndqueue);
+	if (!instance->current_skb)
+		return;		/* done - no more skbs */
+
+	skb = instance->current_skb;
+
+	if (!(buf = instance->current_buffer)) {
+		spin_lock_irq(&instance->send_lock);
+		if (list_empty(&instance->spare_send_buffers)) {
+			instance->current_buffer = NULL;
+			spin_unlock_irq(&instance->send_lock);
+			return;	/* done - no more buffers */
+		}
+		buf = list_entry(instance->spare_send_buffers.next,
+			       struct udsl_send_buffer, list);
+		list_del(&buf->list);
+		spin_unlock_irq(&instance->send_lock);
+
+		buf->free_start = buf->base;
+		buf->free_cells = snd_buf_size;
+
+		instance->current_buffer = buf;
+	}
+
+	num_written = udsl_write_cells(instance, buf->free_cells, skb, &buf->free_start);
+
+	vdbg("udsl_process_send: wrote %u cells from skb 0x%p to buffer 0x%p",
+	     num_written, skb, buf);
+
+	if (!(buf->free_cells -= num_written)) {
+		list_add_tail(&buf->list, &instance->filled_send_buffers);
+		instance->current_buffer = NULL;
+	}
+
+	vdbg("udsl_process_send: buffer contains %d cells, %d left",
+	     snd_buf_size - buf->free_cells, buf->free_cells);
+
+	if (!UDSL_SKB(skb)->num_cells) {
+		struct atm_vcc *vcc = UDSL_SKB(skb)->atm_data.vcc;
+
+		udsl_pop(vcc, skb);
+		instance->current_skb = NULL;
+
+		atomic_inc(&vcc->stats->tx);
+	}
+
+	goto made_progress;
+}
+
+static void udsl_cancel_send(struct udsl_instance_data *instance,
+			     struct atm_vcc *vcc)
+{
+	struct sk_buff *skb, *n;
+
+	dbg("udsl_cancel_send entered");
+	spin_lock_irq(&instance->sndqueue.lock);
+	for (skb = instance->sndqueue.next, n = skb->next;
+	     skb != (struct sk_buff *)&instance->sndqueue;
+	     skb = n, n = skb->next)
+		if (UDSL_SKB(skb)->atm_data.vcc == vcc) {
+			dbg("udsl_cancel_send: popping skb 0x%p", skb);
+			__skb_unlink(skb, &instance->sndqueue);
+			udsl_pop(vcc, skb);
+		}
+	spin_unlock_irq(&instance->sndqueue.lock);
+
+	tasklet_disable(&instance->send_tasklet);
+	if ((skb = instance->current_skb) && (UDSL_SKB(skb)->atm_data.vcc == vcc)) {
+		dbg("udsl_cancel_send: popping current skb (0x%p)", skb);
+		instance->current_skb = NULL;
+		udsl_pop(vcc, skb);
+	}
+	tasklet_enable(&instance->send_tasklet);
+	dbg("udsl_cancel_send done");
+}
+
+static int udsl_atm_send(struct atm_vcc *vcc, struct sk_buff *skb)
+{
+	struct udsl_instance_data *instance = vcc->dev->dev_data;
+	int err;
+
+	vdbg("udsl_atm_send called (skb 0x%p, len %u)", skb, skb->len);
+
+	if (!instance) {
+		dbg("udsl_atm_send: NULL data!");
+		err = -ENODEV;
+		goto fail;
+	}
+
+	if (vcc->qos.aal != ATM_AAL5) {
+		dbg("udsl_atm_send: unsupported ATM type %d!", vcc->qos.aal);
+		err = -EINVAL;
+		goto fail;
+	}
+
+	if (skb->len > ATM_MAX_AAL5_PDU) {
+		dbg("udsl_atm_send: packet too long (%d vs %d)!", skb->len,
+		    ATM_MAX_AAL5_PDU);
+		err = -EINVAL;
+		goto fail;
+	}
+
+	PACKETDEBUG(skb->data, skb->len);
+
+	udsl_groom_skb(vcc, skb);
+	skb_queue_tail(&instance->sndqueue, skb);
+	tasklet_schedule(&instance->send_tasklet);
+
+	return 0;
+
+ fail:
+	udsl_pop(vcc, skb);
+	return err;
+}
+
+/********************
+**  bean counting  **
+********************/
+
+static void udsl_destroy_instance(struct kref *kref)
+{
+	struct udsl_instance_data *instance =
+	    container_of(kref, struct udsl_instance_data, refcount);
+
+	tasklet_kill(&instance->receive_tasklet);
+	tasklet_kill(&instance->send_tasklet);
+	usb_put_dev(instance->usb_dev);
+	kfree(instance);
+}
+
+void udsl_get_instance(struct udsl_instance_data *instance)
+{
+	kref_get(&instance->refcount);
+}
+
+void udsl_put_instance(struct udsl_instance_data *instance)
+{
+	kref_put(&instance->refcount, udsl_destroy_instance);
+}
+
+/**********
+**  ATM  **
+**********/
+
+static void udsl_atm_dev_close(struct atm_dev *dev)
+{
+	struct udsl_instance_data *instance = dev->dev_data;
+
+	dev->dev_data = NULL;
+	udsl_put_instance(instance);
+}
+
+static int udsl_atm_proc_read(struct atm_dev *atm_dev, loff_t * pos, char *page)
+{
+	struct udsl_instance_data *instance = atm_dev->dev_data;
+	int left = *pos;
+
+	if (!instance) {
+		dbg("udsl_atm_proc_read: NULL instance!");
+		return -ENODEV;
+	}
+
+	if (!left--)
+		return sprintf(page, "%s\n", instance->description);
+
+	if (!left--)
+		return sprintf(page, "MAC: %02x:%02x:%02x:%02x:%02x:%02x\n",
+			       atm_dev->esi[0], atm_dev->esi[1],
+			       atm_dev->esi[2], atm_dev->esi[3],
+			       atm_dev->esi[4], atm_dev->esi[5]);
+
+	if (!left--)
+		return sprintf(page,
+			       "AAL5: tx %d ( %d err ), rx %d ( %d err, %d drop )\n",
+			       atomic_read(&atm_dev->stats.aal5.tx),
+			       atomic_read(&atm_dev->stats.aal5.tx_err),
+			       atomic_read(&atm_dev->stats.aal5.rx),
+			       atomic_read(&atm_dev->stats.aal5.rx_err),
+			       atomic_read(&atm_dev->stats.aal5.rx_drop));
+
+	if (!left--) {
+		switch (atm_dev->signal) {
+		case ATM_PHY_SIG_FOUND:
+			sprintf(page, "Line up");
+			break;
+		case ATM_PHY_SIG_LOST:
+			sprintf(page, "Line down");
+			break;
+		default:
+			sprintf(page, "Line state unknown");
+			break;
+		}
+
+		if (instance->usb_dev->state == USB_STATE_NOTATTACHED)
+			strcat(page, ", disconnected\n");
+		else {
+			if (instance->status == UDSL_LOADED_FIRMWARE)
+				strcat(page, ", firmware loaded\n");
+			else if (instance->status == UDSL_LOADING_FIRMWARE)
+				strcat(page, ", firmware loading\n");
+			else
+				strcat(page, ", no firmware\n");
+		}
+
+		return strlen(page);
+	}
+
+	return 0;
+}
+
+static int udsl_atm_open(struct atm_vcc *vcc)
+{
+	struct udsl_instance_data *instance = vcc->dev->dev_data;
+	struct udsl_vcc_data *new;
+	unsigned int max_pdu;
+	int vci = vcc->vci;
+	short vpi = vcc->vpi;
+	int err;
+
+	dbg("udsl_atm_open: vpi %hd, vci %d", vpi, vci);
+
+	if (!instance) {
+		dbg("udsl_atm_open: NULL data!");
+		return -ENODEV;
+	}
+
+	/* only support AAL5 */
+	if ((vcc->qos.aal != ATM_AAL5) || (vcc->qos.rxtp.max_sdu < 0)
+	    || (vcc->qos.rxtp.max_sdu > ATM_MAX_AAL5_PDU)) {
+		dbg("udsl_atm_open: unsupported ATM type %d!", vcc->qos.aal);
+		return -EINVAL;
+	}
+
+	if (instance->firmware_wait &&
+	    (err = instance->firmware_wait(instance)) < 0) {
+		dbg("udsl_atm_open: firmware not loaded (%d)!", err);
+		return err;
+	}
+
+	down(&instance->serialize);	/* vs self, udsl_atm_close */
+
+	if (udsl_find_vcc(instance, vpi, vci)) {
+		dbg("udsl_atm_open: %hd/%d already in use!", vpi, vci);
+		up(&instance->serialize);
+		return -EADDRINUSE;
+	}
+
+	if (!(new = kmalloc(sizeof(struct udsl_vcc_data), GFP_KERNEL))) {
+		dbg("udsl_atm_open: no memory for vcc_data!");
+		up(&instance->serialize);
+		return -ENOMEM;
+	}
+
+	memset(new, 0, sizeof(struct udsl_vcc_data));
+	new->vcc = vcc;
+	new->vpi = vpi;
+	new->vci = vci;
+
+	/* udsl_extract_cells requires at least one cell */
+	max_pdu = max(1, UDSL_NUM_CELLS(vcc->qos.rxtp.max_sdu)) * ATM_CELL_PAYLOAD;
+	if (!(new->sarb = alloc_skb(max_pdu, GFP_KERNEL))) {
+		dbg("udsl_atm_open: no memory for SAR buffer!");
+		kfree(new);
+		up(&instance->serialize);
+		return -ENOMEM;
+	}
+
+	vcc->dev_data = new;
+
+	tasklet_disable(&instance->receive_tasklet);
+	list_add(&new->list, &instance->vcc_list);
+	tasklet_enable(&instance->receive_tasklet);
+
+	set_bit(ATM_VF_ADDR, &vcc->flags);
+	set_bit(ATM_VF_PARTIAL, &vcc->flags);
+	set_bit(ATM_VF_READY, &vcc->flags);
+
+	up(&instance->serialize);
+
+	tasklet_schedule(&instance->receive_tasklet);
+
+	dbg("udsl_atm_open: allocated vcc data 0x%p (max_pdu: %u)", new, max_pdu);
+
+	return 0;
+}
+
+static void udsl_atm_close(struct atm_vcc *vcc)
+{
+	struct udsl_instance_data *instance = vcc->dev->dev_data;
+	struct udsl_vcc_data *vcc_data = vcc->dev_data;
+
+	dbg("udsl_atm_close called");
+
+	if (!instance || !vcc_data) {
+		dbg("udsl_atm_close: NULL data!");
+		return;
+	}
+
+	dbg("udsl_atm_close: deallocating vcc 0x%p with vpi %d vci %d",
+	    vcc_data, vcc_data->vpi, vcc_data->vci);
+
+	udsl_cancel_send(instance, vcc);
+
+	down(&instance->serialize);	/* vs self, udsl_atm_open */
+
+	tasklet_disable(&instance->receive_tasklet);
+	list_del(&vcc_data->list);
+	tasklet_enable(&instance->receive_tasklet);
+
+	kfree_skb(vcc_data->sarb);
+	vcc_data->sarb = NULL;
+
+	kfree(vcc_data);
+	vcc->dev_data = NULL;
+
+	vcc->vpi = ATM_VPI_UNSPEC;
+	vcc->vci = ATM_VCI_UNSPEC;
+	clear_bit(ATM_VF_READY, &vcc->flags);
+	clear_bit(ATM_VF_PARTIAL, &vcc->flags);
+	clear_bit(ATM_VF_ADDR, &vcc->flags);
+
+	up(&instance->serialize);
+
+	dbg("udsl_atm_close successful");
+}
+
+static int udsl_atm_ioctl(struct atm_dev *dev, unsigned int cmd,
+			  void __user * arg)
+{
+	switch (cmd) {
+	case ATM_QUERYLOOP:
+		return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0;
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+/**********
+**  USB  **
+**********/
+
+int udsl_instance_setup(struct usb_device *dev,
+			struct udsl_instance_data *instance)
+{
+	char *buf;
+	int i, length;
+
+	kref_init(&instance->refcount);	/* one for USB */
+	udsl_get_instance(instance);	/* one for ATM */
+
+	init_MUTEX(&instance->serialize);
+
+	instance->usb_dev = dev;
+
+	INIT_LIST_HEAD(&instance->vcc_list);
+
+	instance->status = UDSL_NO_FIRMWARE;
+	init_waitqueue_head(&instance->firmware_waiters);
+
+	spin_lock_init(&instance->receive_lock);
+	INIT_LIST_HEAD(&instance->spare_receivers);
+	INIT_LIST_HEAD(&instance->filled_receive_buffers);
+
+	tasklet_init(&instance->receive_tasklet, udsl_process_receive, (unsigned long)instance);
+	INIT_LIST_HEAD(&instance->spare_receive_buffers);
+
+	skb_queue_head_init(&instance->sndqueue);
+
+	spin_lock_init(&instance->send_lock);
+	INIT_LIST_HEAD(&instance->spare_senders);
+	INIT_LIST_HEAD(&instance->spare_send_buffers);
+
+	tasklet_init(&instance->send_tasklet, udsl_process_send,
+		     (unsigned long)instance);
+	INIT_LIST_HEAD(&instance->filled_send_buffers);
+
+	/* receive init */
+	for (i = 0; i < num_rcv_urbs; i++) {
+		struct udsl_receiver *rcv = &(instance->receivers[i]);
+
+		if (!(rcv->urb = usb_alloc_urb(0, GFP_KERNEL))) {
+			dbg("udsl_usb_probe: no memory for receive urb %d!", i);
+			goto fail;
+		}
+
+		rcv->instance = instance;
+
+		list_add(&rcv->list, &instance->spare_receivers);
+	}
+
+	for (i = 0; i < num_rcv_bufs; i++) {
+		struct udsl_receive_buffer *buf =
+		    &(instance->receive_buffers[i]);
+
+		buf->base = kmalloc(rcv_buf_size * (ATM_CELL_SIZE + instance->rcv_padding),
+				    GFP_KERNEL);
+		if (!buf->base) {
+			dbg("udsl_usb_probe: no memory for receive buffer %d!", i);
+			goto fail;
+		}
+
+		list_add(&buf->list, &instance->spare_receive_buffers);
+	}
+
+	/* send init */
+	for (i = 0; i < num_snd_urbs; i++) {
+		struct udsl_sender *snd = &(instance->senders[i]);
+
+		if (!(snd->urb = usb_alloc_urb(0, GFP_KERNEL))) {
+			dbg("udsl_usb_probe: no memory for send urb %d!", i);
+			goto fail;
+		}
+
+		snd->instance = instance;
+
+		list_add(&snd->list, &instance->spare_senders);
+	}
+
+	for (i = 0; i < num_snd_bufs; i++) {
+		struct udsl_send_buffer *buf = &(instance->send_buffers[i]);
+
+		buf->base = kmalloc(snd_buf_size * (ATM_CELL_SIZE + instance->snd_padding),
+				    GFP_KERNEL);
+		if (!buf->base) {
+			dbg("udsl_usb_probe: no memory for send buffer %d!", i);
+			goto fail;
+		}
+
+		list_add(&buf->list, &instance->spare_send_buffers);
+	}
+
+	/* ATM init */
+	instance->atm_dev = atm_dev_register(instance->driver_name,
+					     &udsl_atm_devops, -1, NULL);
+	if (!instance->atm_dev) {
+		dbg("udsl_usb_probe: failed to register ATM device!");
+		goto fail;
+	}
+
+	instance->atm_dev->ci_range.vpi_bits = ATM_CI_MAX;
+	instance->atm_dev->ci_range.vci_bits = ATM_CI_MAX;
+	instance->atm_dev->signal = ATM_PHY_SIG_UNKNOWN;
+
+	/* temp init ATM device, set to 128kbit */
+	instance->atm_dev->link_rate = 128 * 1000 / 424;
+
+	/* device description */
+	buf = instance->description;
+	length = sizeof(instance->description);
+
+	if ((i = usb_string(dev, dev->descriptor.iProduct, buf, length)) < 0)
+		goto finish;
+
+	buf += i;
+	length -= i;
+
+	i = scnprintf(buf, length, " (");
+	buf += i;
+	length -= i;
+
+	if (length <= 0 || (i = usb_make_path(dev, buf, length)) < 0)
+		goto finish;
+
+	buf += i;
+	length -= i;
+
+	snprintf(buf, length, ")");
+
+ finish:
+	/* ready for ATM callbacks */
+	wmb();
+	instance->atm_dev->dev_data = instance;
+
+	usb_get_dev(dev);
+
+	return 0;
+
+ fail:
+	for (i = 0; i < num_snd_bufs; i++)
+		kfree(instance->send_buffers[i].base);
+
+	for (i = 0; i < num_snd_urbs; i++)
+		usb_free_urb(instance->senders[i].urb);
+
+	for (i = 0; i < num_rcv_bufs; i++)
+		kfree(instance->receive_buffers[i].base);
+
+	for (i = 0; i < num_rcv_urbs; i++)
+		usb_free_urb(instance->receivers[i].urb);
+
+	return -ENOMEM;
+}
+
+void udsl_instance_disconnect(struct udsl_instance_data *instance)
+{
+	int i;
+
+	dbg("udsl_instance_disconnect entered");
+
+	if (!instance) {
+		dbg("udsl_instance_disconnect: NULL instance!");
+		return;
+	}
+
+	/* receive finalize */
+	tasklet_disable(&instance->receive_tasklet);
+
+	for (i = 0; i < num_rcv_urbs; i++)
+		usb_kill_urb(instance->receivers[i].urb);
+
+	/* no need to take the spinlock */
+	INIT_LIST_HEAD(&instance->filled_receive_buffers);
+	INIT_LIST_HEAD(&instance->spare_receive_buffers);
+
+	tasklet_enable(&instance->receive_tasklet);
+
+	for (i = 0; i < num_rcv_urbs; i++)
+		usb_free_urb(instance->receivers[i].urb);
+
+	for (i = 0; i < num_rcv_bufs; i++)
+		kfree(instance->receive_buffers[i].base);
+
+	/* send finalize */
+	tasklet_disable(&instance->send_tasklet);
+
+	for (i = 0; i < num_snd_urbs; i++)
+		usb_kill_urb(instance->senders[i].urb);
+
+	/* no need to take the spinlock */
+	INIT_LIST_HEAD(&instance->spare_senders);
+	INIT_LIST_HEAD(&instance->spare_send_buffers);
+	instance->current_buffer = NULL;
+
+	tasklet_enable(&instance->send_tasklet);
+
+	for (i = 0; i < num_snd_urbs; i++)
+		usb_free_urb(instance->senders[i].urb);
+
+	for (i = 0; i < num_snd_bufs; i++)
+		kfree(instance->send_buffers[i].base);
+
+	/* ATM finalize */
+	shutdown_atm_dev(instance->atm_dev);
+}
+
+EXPORT_SYMBOL_GPL(udsl_get_instance);
+EXPORT_SYMBOL_GPL(udsl_put_instance);
+EXPORT_SYMBOL_GPL(udsl_instance_setup);
+EXPORT_SYMBOL_GPL(udsl_instance_disconnect);
+
+/***********
+**  init  **
+***********/
+
+static int __init udsl_usb_init(void)
+{
+	dbg("udsl_usb_init: driver version " DRIVER_VERSION);
+
+	if (sizeof(struct udsl_control) > sizeof(((struct sk_buff *) 0)->cb)) {
+		printk(KERN_ERR __FILE__ ": unusable with this kernel!\n");
+		return -EIO;
+	}
+
+	if ((num_rcv_urbs > UDSL_MAX_RCV_URBS)
+	    || (num_snd_urbs > UDSL_MAX_SND_URBS)
+	    || (num_rcv_bufs > UDSL_MAX_RCV_BUFS)
+	    || (num_snd_bufs > UDSL_MAX_SND_BUFS)
+	    || (rcv_buf_size > UDSL_MAX_RCV_BUF_SIZE)
+	    || (snd_buf_size > UDSL_MAX_SND_BUF_SIZE))
+		return -EINVAL;
+
+	return 0;
+}
+
+static void __exit udsl_usb_exit(void)
+{
+}
+
+module_init(udsl_usb_init);
+module_exit(udsl_usb_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRIVER_VERSION);
+
+/************
+**  debug  **
+************/
+
+#ifdef VERBOSE_DEBUG
+static int udsl_print_packet(const unsigned char *data, int len)
+{
+	unsigned char buffer[256];
+	int i = 0, j = 0;
+
+	for (i = 0; i < len;) {
+		buffer[0] = '\0';
+		sprintf(buffer, "%.3d :", i);
+		for (j = 0; (j < 16) && (i < len); j++, i++) {
+			sprintf(buffer, "%s %2.2x", buffer, data[i]);
+		}
+		dbg("%s", buffer);
+	}
+	return i;
+}
+#endif