xref: /linux/drivers/usb/atm/usbatm.c (revision be54f8c558027a218423134dd9b8c7c46d92204a)
1  // SPDX-License-Identifier: GPL-2.0+
2  /******************************************************************************
3   *  usbatm.c - Generic USB xDSL driver core
4   *
5   *  Copyright (C) 2001, Alcatel
6   *  Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas
7   *  Copyright (C) 2004, David Woodhouse, Roman Kagan
8   ******************************************************************************/
9  
10  /*
11   *  Written by Johan Verrept, Duncan Sands (duncan.sands@free.fr) and David Woodhouse
12   *
13   *  1.7+:	- See the check-in logs
14   *
15   *  1.6:	- No longer opens a connection if the firmware is not loaded
16   *  		- Added support for the speedtouch 330
17   *  		- Removed the limit on the number of devices
18   *  		- Module now autoloads on device plugin
19   *  		- Merged relevant parts of sarlib
20   *  		- Replaced the kernel thread with a tasklet
21   *  		- New packet transmission code
22   *  		- Changed proc file contents
23   *  		- Fixed all known SMP races
24   *  		- Many fixes and cleanups
25   *  		- Various fixes by Oliver Neukum (oliver@neukum.name)
26   *
27   *  1.5A:	- Version for inclusion in 2.5 series kernel
28   *		- Modifications by Richard Purdie (rpurdie@rpsys.net)
29   *		- made compatible with kernel 2.5.6 onwards by changing
30   *		usbatm_usb_send_data_context->urb to a pointer and adding code
31   *		to alloc and free it
32   *		- remove_wait_queue() added to usbatm_atm_processqueue_thread()
33   *
34   *  1.5:	- fixed memory leak when atmsar_decode_aal5 returned NULL.
35   *		(reported by stephen.robinson@zen.co.uk)
36   *
37   *  1.4:	- changed the spin_lock() under interrupt to spin_lock_irqsave()
38   *		- unlink all active send urbs of a vcc that is being closed.
39   *
40   *  1.3.1:	- added the version number
41   *
42   *  1.3:	- Added multiple send urb support
43   *		- fixed memory leak and vcc->tx_inuse starvation bug
44   *		  when not enough memory left in vcc.
45   *
46   *  1.2:	- Fixed race condition in usbatm_usb_send_data()
47   *  1.1:	- Turned off packet debugging
48   *
49   */
50  
51  #include "usbatm.h"
52  
53  #include <linux/uaccess.h>
54  #include <linux/crc32.h>
55  #include <linux/errno.h>
56  #include <linux/init.h>
57  #include <linux/interrupt.h>
58  #include <linux/kernel.h>
59  #include <linux/module.h>
60  #include <linux/moduleparam.h>
61  #include <linux/netdevice.h>
62  #include <linux/proc_fs.h>
63  #include <linux/sched/signal.h>
64  #include <linux/signal.h>
65  #include <linux/slab.h>
66  #include <linux/stat.h>
67  #include <linux/timer.h>
68  #include <linux/wait.h>
69  #include <linux/kthread.h>
70  #include <linux/ratelimit.h>
71  
72  #ifdef VERBOSE_DEBUG
73  static int usbatm_print_packet(struct usbatm_data *instance, const unsigned char *data, int len);
74  #define PACKETDEBUG(arg...)	usbatm_print_packet(arg)
75  #define vdbg(arg...)		dev_dbg(arg)
76  #else
77  #define PACKETDEBUG(arg...)
78  #define vdbg(arg...)
79  #endif
80  
81  #define DRIVER_AUTHOR	"Johan Verrept, Duncan Sands <duncan.sands@free.fr>"
82  #define DRIVER_DESC	"Generic USB ATM/DSL I/O"
83  
84  static const char usbatm_driver_name[] = "usbatm";
85  
86  #define UDSL_MAX_RCV_URBS		16
87  #define UDSL_MAX_SND_URBS		16
88  #define UDSL_MAX_BUF_SIZE		65536
89  #define UDSL_DEFAULT_RCV_URBS		4
90  #define UDSL_DEFAULT_SND_URBS		4
91  #define UDSL_DEFAULT_RCV_BUF_SIZE	3392	/* 64 * ATM_CELL_SIZE */
92  #define UDSL_DEFAULT_SND_BUF_SIZE	3392	/* 64 * ATM_CELL_SIZE */
93  
94  #define ATM_CELL_HEADER			(ATM_CELL_SIZE - ATM_CELL_PAYLOAD)
95  
96  #define THROTTLE_MSECS			100	/* delay to recover processing after urb submission fails */
97  
98  static unsigned int num_rcv_urbs = UDSL_DEFAULT_RCV_URBS;
99  static unsigned int num_snd_urbs = UDSL_DEFAULT_SND_URBS;
100  static unsigned int rcv_buf_bytes = UDSL_DEFAULT_RCV_BUF_SIZE;
101  static unsigned int snd_buf_bytes = UDSL_DEFAULT_SND_BUF_SIZE;
102  
103  module_param(num_rcv_urbs, uint, S_IRUGO);
104  MODULE_PARM_DESC(num_rcv_urbs,
105  		 "Number of urbs used for reception (range: 0-"
106  		 __MODULE_STRING(UDSL_MAX_RCV_URBS) ", default: "
107  		 __MODULE_STRING(UDSL_DEFAULT_RCV_URBS) ")");
108  
109  module_param(num_snd_urbs, uint, S_IRUGO);
110  MODULE_PARM_DESC(num_snd_urbs,
111  		 "Number of urbs used for transmission (range: 0-"
112  		 __MODULE_STRING(UDSL_MAX_SND_URBS) ", default: "
113  		 __MODULE_STRING(UDSL_DEFAULT_SND_URBS) ")");
114  
115  module_param(rcv_buf_bytes, uint, S_IRUGO);
116  MODULE_PARM_DESC(rcv_buf_bytes,
117  		 "Size of the buffers used for reception, in bytes (range: 1-"
118  		 __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: "
119  		 __MODULE_STRING(UDSL_DEFAULT_RCV_BUF_SIZE) ")");
120  
121  module_param(snd_buf_bytes, uint, S_IRUGO);
122  MODULE_PARM_DESC(snd_buf_bytes,
123  		 "Size of the buffers used for transmission, in bytes (range: 1-"
124  		 __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: "
125  		 __MODULE_STRING(UDSL_DEFAULT_SND_BUF_SIZE) ")");
126  
127  
128  /* receive */
129  
130  struct usbatm_vcc_data {
131  	/* vpi/vci lookup */
132  	struct list_head list;
133  	short vpi;
134  	int vci;
135  	struct atm_vcc *vcc;
136  
137  	/* raw cell reassembly */
138  	struct sk_buff *sarb;
139  };
140  
141  
142  /* send */
143  
144  struct usbatm_control {
145  	struct atm_skb_data atm;
146  	u32 len;
147  	u32 crc;
148  };
149  
150  #define UDSL_SKB(x)		((struct usbatm_control *)(x)->cb)
151  
152  
153  /* ATM */
154  
155  static void usbatm_atm_dev_close(struct atm_dev *atm_dev);
156  static int usbatm_atm_open(struct atm_vcc *vcc);
157  static void usbatm_atm_close(struct atm_vcc *vcc);
158  static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, void __user *arg);
159  static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb);
160  static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page);
161  
162  static const struct atmdev_ops usbatm_atm_devops = {
163  	.dev_close	= usbatm_atm_dev_close,
164  	.open		= usbatm_atm_open,
165  	.close		= usbatm_atm_close,
166  	.ioctl		= usbatm_atm_ioctl,
167  	.send		= usbatm_atm_send,
168  	.proc_read	= usbatm_atm_proc_read,
169  	.owner		= THIS_MODULE,
170  };
171  
172  
173  /***********
174  **  misc  **
175  ***********/
176  
usbatm_pdu_length(unsigned int length)177  static inline unsigned int usbatm_pdu_length(unsigned int length)
178  {
179  	length += ATM_CELL_PAYLOAD - 1 + ATM_AAL5_TRAILER;
180  	return length - length % ATM_CELL_PAYLOAD;
181  }
182  
usbatm_pop(struct atm_vcc * vcc,struct sk_buff * skb)183  static inline void usbatm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
184  {
185  	if (vcc->pop)
186  		vcc->pop(vcc, skb);
187  	else
188  		dev_kfree_skb_any(skb);
189  }
190  
191  
192  /***********
193  **  urbs  **
194  ************/
195  
usbatm_pop_urb(struct usbatm_channel * channel)196  static struct urb *usbatm_pop_urb(struct usbatm_channel *channel)
197  {
198  	struct urb *urb;
199  
200  	spin_lock_irq(&channel->lock);
201  	if (list_empty(&channel->list)) {
202  		spin_unlock_irq(&channel->lock);
203  		return NULL;
204  	}
205  
206  	urb = list_entry(channel->list.next, struct urb, urb_list);
207  	list_del(&urb->urb_list);
208  	spin_unlock_irq(&channel->lock);
209  
210  	return urb;
211  }
212  
usbatm_submit_urb(struct urb * urb)213  static int usbatm_submit_urb(struct urb *urb)
214  {
215  	struct usbatm_channel *channel = urb->context;
216  	int ret;
217  
218  	/* vdbg("%s: submitting urb 0x%p, size %u",
219  	     __func__, urb, urb->transfer_buffer_length); */
220  
221  	ret = usb_submit_urb(urb, GFP_ATOMIC);
222  	if (ret) {
223  		if (printk_ratelimit())
224  			atm_warn(channel->usbatm, "%s: urb 0x%p submission failed (%d)!\n",
225  				__func__, urb, ret);
226  
227  		/* consider all errors transient and return the buffer back to the queue */
228  		urb->status = -EAGAIN;
229  		spin_lock_irq(&channel->lock);
230  
231  		/* must add to the front when sending; doesn't matter when receiving */
232  		list_add(&urb->urb_list, &channel->list);
233  
234  		spin_unlock_irq(&channel->lock);
235  
236  		/* make sure the channel doesn't stall */
237  		mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS));
238  	}
239  
240  	return ret;
241  }
242  
usbatm_complete(struct urb * urb)243  static void usbatm_complete(struct urb *urb)
244  {
245  	struct usbatm_channel *channel = urb->context;
246  	unsigned long flags;
247  	int status = urb->status;
248  
249  	/* vdbg("%s: urb 0x%p, status %d, actual_length %d",
250  	     __func__, urb, status, urb->actual_length); */
251  
252  	/* Can be invoked from task context, protect against interrupts */
253  	spin_lock_irqsave(&channel->lock, flags);
254  
255  	/* must add to the back when receiving; doesn't matter when sending */
256  	list_add_tail(&urb->urb_list, &channel->list);
257  
258  	spin_unlock_irqrestore(&channel->lock, flags);
259  
260  	if (unlikely(status) &&
261  			(!(channel->usbatm->flags & UDSL_IGNORE_EILSEQ) ||
262  			 status != -EILSEQ)) {
263  		if (status == -ESHUTDOWN)
264  			return;
265  
266  		if (printk_ratelimit())
267  			atm_warn(channel->usbatm, "%s: urb 0x%p failed (%d)!\n",
268  				__func__, urb, status);
269  		/* throttle processing in case of an error */
270  		mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS));
271  	} else
272  		tasklet_schedule(&channel->tasklet);
273  }
274  
275  
276  /*************
277  **  decode  **
278  *************/
279  
usbatm_find_vcc(struct usbatm_data * instance,short vpi,int vci)280  static inline struct usbatm_vcc_data *usbatm_find_vcc(struct usbatm_data *instance,
281  						  short vpi, int vci)
282  {
283  	struct usbatm_vcc_data *vcc_data;
284  
285  	list_for_each_entry(vcc_data, &instance->vcc_list, list)
286  		if ((vcc_data->vci == vci) && (vcc_data->vpi == vpi))
287  			return vcc_data;
288  	return NULL;
289  }
290  
usbatm_extract_one_cell(struct usbatm_data * instance,unsigned char * source)291  static void usbatm_extract_one_cell(struct usbatm_data *instance, unsigned char *source)
292  {
293  	struct atm_vcc *vcc;
294  	struct sk_buff *sarb;
295  	short vpi = ((source[0] & 0x0f) << 4)  | (source[1] >> 4);
296  	int vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) | (source[3] >> 4);
297  	u8 pti = ((source[3] & 0xe) >> 1);
298  
299  	if ((vci != instance->cached_vci) || (vpi != instance->cached_vpi)) {
300  		instance->cached_vpi = vpi;
301  		instance->cached_vci = vci;
302  
303  		instance->cached_vcc = usbatm_find_vcc(instance, vpi, vci);
304  
305  		if (!instance->cached_vcc)
306  			atm_rldbg(instance, "%s: unknown vpi/vci (%hd/%d)!\n", __func__, vpi, vci);
307  	}
308  
309  	if (!instance->cached_vcc)
310  		return;
311  
312  	vcc = instance->cached_vcc->vcc;
313  
314  	/* OAM F5 end-to-end */
315  	if (pti == ATM_PTI_E2EF5) {
316  		if (printk_ratelimit())
317  			atm_warn(instance, "%s: OAM not supported (vpi %d, vci %d)!\n",
318  				__func__, vpi, vci);
319  		atomic_inc(&vcc->stats->rx_err);
320  		return;
321  	}
322  
323  	sarb = instance->cached_vcc->sarb;
324  
325  	if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) {
326  		atm_rldbg(instance, "%s: buffer overrun (sarb->len %u, vcc: 0x%p)!\n",
327  				__func__, sarb->len, vcc);
328  		/* discard cells already received */
329  		skb_trim(sarb, 0);
330  	}
331  
332  	memcpy(skb_tail_pointer(sarb), source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD);
333  	__skb_put(sarb, ATM_CELL_PAYLOAD);
334  
335  	if (pti & 1) {
336  		struct sk_buff *skb;
337  		unsigned int length;
338  		unsigned int pdu_length;
339  
340  		length = (source[ATM_CELL_SIZE - 6] << 8) + source[ATM_CELL_SIZE - 5];
341  
342  		/* guard against overflow */
343  		if (length > ATM_MAX_AAL5_PDU) {
344  			atm_rldbg(instance, "%s: bogus length %u (vcc: 0x%p)!\n",
345  				  __func__, length, vcc);
346  			atomic_inc(&vcc->stats->rx_err);
347  			goto out;
348  		}
349  
350  		pdu_length = usbatm_pdu_length(length);
351  
352  		if (sarb->len < pdu_length) {
353  			atm_rldbg(instance, "%s: bogus pdu_length %u (sarb->len: %u, vcc: 0x%p)!\n",
354  				  __func__, pdu_length, sarb->len, vcc);
355  			atomic_inc(&vcc->stats->rx_err);
356  			goto out;
357  		}
358  
359  		if (crc32_be(~0, skb_tail_pointer(sarb) - pdu_length, pdu_length) != 0xc704dd7b) {
360  			atm_rldbg(instance, "%s: packet failed crc check (vcc: 0x%p)!\n",
361  				  __func__, vcc);
362  			atomic_inc(&vcc->stats->rx_err);
363  			goto out;
364  		}
365  
366  		vdbg(&instance->usb_intf->dev,
367  		     "%s: got packet (length: %u, pdu_length: %u, vcc: 0x%p)",
368  		     __func__, length, pdu_length, vcc);
369  
370  		skb = dev_alloc_skb(length);
371  		if (!skb) {
372  			if (printk_ratelimit())
373  				atm_err(instance, "%s: no memory for skb (length: %u)!\n",
374  					__func__, length);
375  			atomic_inc(&vcc->stats->rx_drop);
376  			goto out;
377  		}
378  
379  		vdbg(&instance->usb_intf->dev,
380  		     "%s: allocated new sk_buff (skb: 0x%p, skb->truesize: %u)",
381  		     __func__, skb, skb->truesize);
382  
383  		if (!atm_charge(vcc, skb->truesize)) {
384  			atm_rldbg(instance, "%s: failed atm_charge (skb->truesize: %u)!\n",
385  				  __func__, skb->truesize);
386  			dev_kfree_skb_any(skb);
387  			goto out;	/* atm_charge increments rx_drop */
388  		}
389  
390  		skb_copy_to_linear_data(skb,
391  					skb_tail_pointer(sarb) - pdu_length,
392  					length);
393  		__skb_put(skb, length);
394  
395  		vdbg(&instance->usb_intf->dev,
396  		     "%s: sending skb 0x%p, skb->len %u, skb->truesize %u",
397  		     __func__, skb, skb->len, skb->truesize);
398  
399  		PACKETDEBUG(instance, skb->data, skb->len);
400  
401  		vcc->push(vcc, skb);
402  
403  		atomic_inc(&vcc->stats->rx);
404  	out:
405  		skb_trim(sarb, 0);
406  	}
407  }
408  
usbatm_extract_cells(struct usbatm_data * instance,unsigned char * source,unsigned int avail_data)409  static void usbatm_extract_cells(struct usbatm_data *instance,
410  		unsigned char *source, unsigned int avail_data)
411  {
412  	unsigned int stride = instance->rx_channel.stride;
413  	unsigned int buf_usage = instance->buf_usage;
414  
415  	/* extract cells from incoming data, taking into account that
416  	 * the length of avail data may not be a multiple of stride */
417  
418  	if (buf_usage > 0) {
419  		/* we have a partially received atm cell */
420  		unsigned char *cell_buf = instance->cell_buf;
421  		unsigned int space_left = stride - buf_usage;
422  
423  		if (avail_data >= space_left) {
424  			/* add new data and process cell */
425  			memcpy(cell_buf + buf_usage, source, space_left);
426  			source += space_left;
427  			avail_data -= space_left;
428  			usbatm_extract_one_cell(instance, cell_buf);
429  			instance->buf_usage = 0;
430  		} else {
431  			/* not enough data to fill the cell */
432  			memcpy(cell_buf + buf_usage, source, avail_data);
433  			instance->buf_usage = buf_usage + avail_data;
434  			return;
435  		}
436  	}
437  
438  	for (; avail_data >= stride; avail_data -= stride, source += stride)
439  		usbatm_extract_one_cell(instance, source);
440  
441  	if (avail_data > 0) {
442  		/* length was not a multiple of stride -
443  		 * save remaining data for next call */
444  		memcpy(instance->cell_buf, source, avail_data);
445  		instance->buf_usage = avail_data;
446  	}
447  }
448  
449  
450  /*************
451  **  encode  **
452  *************/
453  
usbatm_write_cells(struct usbatm_data * instance,struct sk_buff * skb,u8 * target,unsigned int avail_space)454  static unsigned int usbatm_write_cells(struct usbatm_data *instance,
455  				       struct sk_buff *skb,
456  				       u8 *target, unsigned int avail_space)
457  {
458  	struct usbatm_control *ctrl = UDSL_SKB(skb);
459  	struct atm_vcc *vcc = ctrl->atm.vcc;
460  	unsigned int bytes_written;
461  	unsigned int stride = instance->tx_channel.stride;
462  
463  	for (bytes_written = 0; bytes_written < avail_space && ctrl->len;
464  	     bytes_written += stride, target += stride) {
465  		unsigned int data_len = min_t(unsigned int, skb->len, ATM_CELL_PAYLOAD);
466  		unsigned int left = ATM_CELL_PAYLOAD - data_len;
467  		u8 *ptr = target;
468  
469  		ptr[0] = vcc->vpi >> 4;
470  		ptr[1] = (vcc->vpi << 4) | (vcc->vci >> 12);
471  		ptr[2] = vcc->vci >> 4;
472  		ptr[3] = vcc->vci << 4;
473  		ptr[4] = 0xec;
474  		ptr += ATM_CELL_HEADER;
475  
476  		skb_copy_from_linear_data(skb, ptr, data_len);
477  		ptr += data_len;
478  		__skb_pull(skb, data_len);
479  
480  		if (!left)
481  			continue;
482  
483  		memset(ptr, 0, left);
484  
485  		if (left >= ATM_AAL5_TRAILER) {	/* trailer will go in this cell */
486  			u8 *trailer = target + ATM_CELL_SIZE - ATM_AAL5_TRAILER;
487  			/* trailer[0] = 0;		UU = 0 */
488  			/* trailer[1] = 0;		CPI = 0 */
489  			trailer[2] = ctrl->len >> 8;
490  			trailer[3] = ctrl->len;
491  
492  			ctrl->crc = ~crc32_be(ctrl->crc, ptr, left - 4);
493  
494  			trailer[4] = ctrl->crc >> 24;
495  			trailer[5] = ctrl->crc >> 16;
496  			trailer[6] = ctrl->crc >> 8;
497  			trailer[7] = ctrl->crc;
498  
499  			target[3] |= 0x2;	/* adjust PTI */
500  
501  			ctrl->len = 0;		/* tag this skb finished */
502  		} else
503  			ctrl->crc = crc32_be(ctrl->crc, ptr, left);
504  	}
505  
506  	return bytes_written;
507  }
508  
509  
510  /**************
511  **  receive  **
512  **************/
513  
usbatm_rx_process(struct tasklet_struct * t)514  static void usbatm_rx_process(struct tasklet_struct *t)
515  {
516  	struct usbatm_data *instance = from_tasklet(instance, t,
517  						    rx_channel.tasklet);
518  	struct urb *urb;
519  
520  	while ((urb = usbatm_pop_urb(&instance->rx_channel))) {
521  		vdbg(&instance->usb_intf->dev,
522  		     "%s: processing urb 0x%p", __func__, urb);
523  
524  		if (usb_pipeisoc(urb->pipe)) {
525  			unsigned char *merge_start = NULL;
526  			unsigned int merge_length = 0;
527  			const unsigned int packet_size = instance->rx_channel.packet_size;
528  			int i;
529  
530  			for (i = 0; i < urb->number_of_packets; i++) {
531  				if (!urb->iso_frame_desc[i].status) {
532  					unsigned int actual_length = urb->iso_frame_desc[i].actual_length;
533  
534  					if (!merge_length)
535  						merge_start = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
536  					merge_length += actual_length;
537  					if (merge_length && (actual_length < packet_size)) {
538  						usbatm_extract_cells(instance, merge_start, merge_length);
539  						merge_length = 0;
540  					}
541  				} else {
542  					atm_rldbg(instance, "%s: status %d in frame %d!\n", __func__, urb->status, i);
543  					if (merge_length)
544  						usbatm_extract_cells(instance, merge_start, merge_length);
545  					merge_length = 0;
546  					instance->buf_usage = 0;
547  				}
548  			}
549  
550  			if (merge_length)
551  				usbatm_extract_cells(instance, merge_start, merge_length);
552  		} else
553  			if (!urb->status)
554  				usbatm_extract_cells(instance, urb->transfer_buffer, urb->actual_length);
555  			else
556  				instance->buf_usage = 0;
557  
558  		if (usbatm_submit_urb(urb))
559  			return;
560  	}
561  }
562  
563  
564  /***********
565  **  send  **
566  ***********/
567  
usbatm_tx_process(struct tasklet_struct * t)568  static void usbatm_tx_process(struct tasklet_struct *t)
569  {
570  	struct usbatm_data *instance = from_tasklet(instance, t,
571  						    tx_channel.tasklet);
572  	struct sk_buff *skb = instance->current_skb;
573  	struct urb *urb = NULL;
574  	const unsigned int buf_size = instance->tx_channel.buf_size;
575  	unsigned int bytes_written = 0;
576  	u8 *buffer = NULL;
577  
578  	if (!skb)
579  		skb = skb_dequeue(&instance->sndqueue);
580  
581  	while (skb) {
582  		if (!urb) {
583  			urb = usbatm_pop_urb(&instance->tx_channel);
584  			if (!urb)
585  				break;		/* no more senders */
586  			buffer = urb->transfer_buffer;
587  			bytes_written = (urb->status == -EAGAIN) ?
588  				urb->transfer_buffer_length : 0;
589  		}
590  
591  		bytes_written += usbatm_write_cells(instance, skb,
592  						  buffer + bytes_written,
593  						  buf_size - bytes_written);
594  
595  		vdbg(&instance->usb_intf->dev,
596  		     "%s: wrote %u bytes from skb 0x%p to urb 0x%p",
597  		     __func__, bytes_written, skb, urb);
598  
599  		if (!UDSL_SKB(skb)->len) {
600  			struct atm_vcc *vcc = UDSL_SKB(skb)->atm.vcc;
601  
602  			usbatm_pop(vcc, skb);
603  			atomic_inc(&vcc->stats->tx);
604  
605  			skb = skb_dequeue(&instance->sndqueue);
606  		}
607  
608  		if (bytes_written == buf_size || (!skb && bytes_written)) {
609  			urb->transfer_buffer_length = bytes_written;
610  
611  			if (usbatm_submit_urb(urb))
612  				break;
613  			urb = NULL;
614  		}
615  	}
616  
617  	instance->current_skb = skb;
618  }
619  
usbatm_cancel_send(struct usbatm_data * instance,struct atm_vcc * vcc)620  static void usbatm_cancel_send(struct usbatm_data *instance,
621  			       struct atm_vcc *vcc)
622  {
623  	struct sk_buff *skb, *n;
624  
625  	spin_lock_irq(&instance->sndqueue.lock);
626  	skb_queue_walk_safe(&instance->sndqueue, skb, n) {
627  		if (UDSL_SKB(skb)->atm.vcc == vcc) {
628  			atm_dbg(instance, "%s: popping skb 0x%p\n", __func__, skb);
629  			__skb_unlink(skb, &instance->sndqueue);
630  			usbatm_pop(vcc, skb);
631  		}
632  	}
633  	spin_unlock_irq(&instance->sndqueue.lock);
634  
635  	tasklet_disable(&instance->tx_channel.tasklet);
636  	if ((skb = instance->current_skb) && (UDSL_SKB(skb)->atm.vcc == vcc)) {
637  		atm_dbg(instance, "%s: popping current skb (0x%p)\n", __func__, skb);
638  		instance->current_skb = NULL;
639  		usbatm_pop(vcc, skb);
640  	}
641  	tasklet_enable(&instance->tx_channel.tasklet);
642  }
643  
usbatm_atm_send(struct atm_vcc * vcc,struct sk_buff * skb)644  static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb)
645  {
646  	struct usbatm_data *instance = vcc->dev->dev_data;
647  	struct usbatm_control *ctrl = UDSL_SKB(skb);
648  	int err;
649  
650  	/* racy disconnection check - fine */
651  	if (!instance || instance->disconnected) {
652  #ifdef VERBOSE_DEBUG
653  		printk_ratelimited(KERN_DEBUG "%s: %s!\n", __func__, instance ? "disconnected" : "NULL instance");
654  #endif
655  		err = -ENODEV;
656  		goto fail;
657  	}
658  
659  	if (vcc->qos.aal != ATM_AAL5) {
660  		atm_rldbg(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal);
661  		err = -EINVAL;
662  		goto fail;
663  	}
664  
665  	if (skb->len > ATM_MAX_AAL5_PDU) {
666  		atm_rldbg(instance, "%s: packet too long (%d vs %d)!\n",
667  				__func__, skb->len, ATM_MAX_AAL5_PDU);
668  		err = -EINVAL;
669  		goto fail;
670  	}
671  
672  	PACKETDEBUG(instance, skb->data, skb->len);
673  
674  	/* initialize the control block */
675  	ctrl->atm.vcc = vcc;
676  	ctrl->len = skb->len;
677  	ctrl->crc = crc32_be(~0, skb->data, skb->len);
678  
679  	skb_queue_tail(&instance->sndqueue, skb);
680  	tasklet_schedule(&instance->tx_channel.tasklet);
681  
682  	return 0;
683  
684   fail:
685  	usbatm_pop(vcc, skb);
686  	return err;
687  }
688  
689  
690  /********************
691  **  bean counting  **
692  ********************/
693  
usbatm_destroy_instance(struct kref * kref)694  static void usbatm_destroy_instance(struct kref *kref)
695  {
696  	struct usbatm_data *instance = container_of(kref, struct usbatm_data, refcount);
697  
698  	tasklet_kill(&instance->rx_channel.tasklet);
699  	tasklet_kill(&instance->tx_channel.tasklet);
700  	usb_put_dev(instance->usb_dev);
701  	kfree(instance);
702  }
703  
usbatm_get_instance(struct usbatm_data * instance)704  static void usbatm_get_instance(struct usbatm_data *instance)
705  {
706  	kref_get(&instance->refcount);
707  }
708  
usbatm_put_instance(struct usbatm_data * instance)709  static void usbatm_put_instance(struct usbatm_data *instance)
710  {
711  	kref_put(&instance->refcount, usbatm_destroy_instance);
712  }
713  
714  
715  /**********
716  **  ATM  **
717  **********/
718  
usbatm_atm_dev_close(struct atm_dev * atm_dev)719  static void usbatm_atm_dev_close(struct atm_dev *atm_dev)
720  {
721  	struct usbatm_data *instance = atm_dev->dev_data;
722  
723  	if (!instance)
724  		return;
725  
726  	atm_dev->dev_data = NULL; /* catch bugs */
727  	usbatm_put_instance(instance);	/* taken in usbatm_atm_init */
728  }
729  
usbatm_atm_proc_read(struct atm_dev * atm_dev,loff_t * pos,char * page)730  static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page)
731  {
732  	struct usbatm_data *instance = atm_dev->dev_data;
733  	int left = *pos;
734  
735  	if (!instance)
736  		return -ENODEV;
737  
738  	if (!left--)
739  		return sprintf(page, "%s\n", instance->description);
740  
741  	if (!left--)
742  		return sprintf(page, "MAC: %pM\n", atm_dev->esi);
743  
744  	if (!left--)
745  		return sprintf(page,
746  			       "AAL5: tx %d ( %d err ), rx %d ( %d err, %d drop )\n",
747  			       atomic_read(&atm_dev->stats.aal5.tx),
748  			       atomic_read(&atm_dev->stats.aal5.tx_err),
749  			       atomic_read(&atm_dev->stats.aal5.rx),
750  			       atomic_read(&atm_dev->stats.aal5.rx_err),
751  			       atomic_read(&atm_dev->stats.aal5.rx_drop));
752  
753  	if (!left--) {
754  		if (instance->disconnected)
755  			return sprintf(page, "Disconnected\n");
756  		else
757  			switch (atm_dev->signal) {
758  			case ATM_PHY_SIG_FOUND:
759  				return sprintf(page, "Line up\n");
760  			case ATM_PHY_SIG_LOST:
761  				return sprintf(page, "Line down\n");
762  			default:
763  				return sprintf(page, "Line state unknown\n");
764  			}
765  	}
766  
767  	return 0;
768  }
769  
usbatm_atm_open(struct atm_vcc * vcc)770  static int usbatm_atm_open(struct atm_vcc *vcc)
771  {
772  	struct usbatm_data *instance = vcc->dev->dev_data;
773  	struct usbatm_vcc_data *new = NULL;
774  	int ret;
775  	int vci = vcc->vci;
776  	short vpi = vcc->vpi;
777  
778  	if (!instance)
779  		return -ENODEV;
780  
781  	/* only support AAL5 */
782  	if ((vcc->qos.aal != ATM_AAL5)) {
783  		atm_warn(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal);
784  		return -EINVAL;
785  	}
786  
787  	/* sanity checks */
788  	if ((vcc->qos.rxtp.max_sdu < 0) || (vcc->qos.rxtp.max_sdu > ATM_MAX_AAL5_PDU)) {
789  		atm_dbg(instance, "%s: max_sdu %d out of range!\n", __func__, vcc->qos.rxtp.max_sdu);
790  		return -EINVAL;
791  	}
792  
793  	mutex_lock(&instance->serialize);	/* vs self, usbatm_atm_close, usbatm_usb_disconnect */
794  
795  	if (instance->disconnected) {
796  		atm_dbg(instance, "%s: disconnected!\n", __func__);
797  		ret = -ENODEV;
798  		goto fail;
799  	}
800  
801  	if (usbatm_find_vcc(instance, vpi, vci)) {
802  		atm_dbg(instance, "%s: %hd/%d already in use!\n", __func__, vpi, vci);
803  		ret = -EADDRINUSE;
804  		goto fail;
805  	}
806  
807  	new = kzalloc(sizeof(struct usbatm_vcc_data), GFP_KERNEL);
808  	if (!new) {
809  		ret = -ENOMEM;
810  		goto fail;
811  	}
812  
813  	new->vcc = vcc;
814  	new->vpi = vpi;
815  	new->vci = vci;
816  
817  	new->sarb = alloc_skb(usbatm_pdu_length(vcc->qos.rxtp.max_sdu), GFP_KERNEL);
818  	if (!new->sarb) {
819  		atm_err(instance, "%s: no memory for SAR buffer!\n", __func__);
820  		ret = -ENOMEM;
821  		goto fail;
822  	}
823  
824  	vcc->dev_data = new;
825  
826  	tasklet_disable(&instance->rx_channel.tasklet);
827  	instance->cached_vcc = new;
828  	instance->cached_vpi = vpi;
829  	instance->cached_vci = vci;
830  	list_add(&new->list, &instance->vcc_list);
831  	tasklet_enable(&instance->rx_channel.tasklet);
832  
833  	set_bit(ATM_VF_ADDR, &vcc->flags);
834  	set_bit(ATM_VF_PARTIAL, &vcc->flags);
835  	set_bit(ATM_VF_READY, &vcc->flags);
836  
837  	mutex_unlock(&instance->serialize);
838  
839  	atm_dbg(instance, "%s: allocated vcc data 0x%p\n", __func__, new);
840  
841  	return 0;
842  
843  fail:
844  	kfree(new);
845  	mutex_unlock(&instance->serialize);
846  	return ret;
847  }
848  
usbatm_atm_close(struct atm_vcc * vcc)849  static void usbatm_atm_close(struct atm_vcc *vcc)
850  {
851  	struct usbatm_data *instance = vcc->dev->dev_data;
852  	struct usbatm_vcc_data *vcc_data = vcc->dev_data;
853  
854  	if (!instance || !vcc_data)
855  		return;
856  
857  	usbatm_cancel_send(instance, vcc);
858  
859  	mutex_lock(&instance->serialize);	/* vs self, usbatm_atm_open, usbatm_usb_disconnect */
860  
861  	tasklet_disable(&instance->rx_channel.tasklet);
862  	if (instance->cached_vcc == vcc_data) {
863  		instance->cached_vcc = NULL;
864  		instance->cached_vpi = ATM_VPI_UNSPEC;
865  		instance->cached_vci = ATM_VCI_UNSPEC;
866  	}
867  	list_del(&vcc_data->list);
868  	tasklet_enable(&instance->rx_channel.tasklet);
869  
870  	kfree_skb(vcc_data->sarb);
871  	vcc_data->sarb = NULL;
872  
873  	kfree(vcc_data);
874  	vcc->dev_data = NULL;
875  
876  	vcc->vpi = ATM_VPI_UNSPEC;
877  	vcc->vci = ATM_VCI_UNSPEC;
878  	clear_bit(ATM_VF_READY, &vcc->flags);
879  	clear_bit(ATM_VF_PARTIAL, &vcc->flags);
880  	clear_bit(ATM_VF_ADDR, &vcc->flags);
881  
882  	mutex_unlock(&instance->serialize);
883  }
884  
usbatm_atm_ioctl(struct atm_dev * atm_dev,unsigned int cmd,void __user * arg)885  static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd,
886  			  void __user *arg)
887  {
888  	struct usbatm_data *instance = atm_dev->dev_data;
889  
890  	if (!instance || instance->disconnected)
891  		return -ENODEV;
892  
893  	switch (cmd) {
894  	case ATM_QUERYLOOP:
895  		return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0;
896  	default:
897  		return -ENOIOCTLCMD;
898  	}
899  }
900  
usbatm_atm_init(struct usbatm_data * instance)901  static int usbatm_atm_init(struct usbatm_data *instance)
902  {
903  	struct atm_dev *atm_dev;
904  	int ret, i;
905  
906  	/* ATM init.  The ATM initialization scheme suffers from an intrinsic race
907  	 * condition: callbacks we register can be executed at once, before we have
908  	 * initialized the struct atm_dev.  To protect against this, all callbacks
909  	 * abort if atm_dev->dev_data is NULL. */
910  	atm_dev = atm_dev_register(instance->driver_name,
911  				   &instance->usb_intf->dev, &usbatm_atm_devops,
912  				   -1, NULL);
913  	if (!atm_dev) {
914  		usb_err(instance, "%s: failed to register ATM device!\n", __func__);
915  		return -1;
916  	}
917  
918  	instance->atm_dev = atm_dev;
919  
920  	atm_dev->ci_range.vpi_bits = ATM_CI_MAX;
921  	atm_dev->ci_range.vci_bits = ATM_CI_MAX;
922  	atm_dev->signal = ATM_PHY_SIG_UNKNOWN;
923  
924  	/* temp init ATM device, set to 128kbit */
925  	atm_dev->link_rate = 128 * 1000 / 424;
926  
927  	if (instance->driver->atm_start && ((ret = instance->driver->atm_start(instance, atm_dev)) < 0)) {
928  		atm_err(instance, "%s: atm_start failed: %d!\n", __func__, ret);
929  		goto fail;
930  	}
931  
932  	usbatm_get_instance(instance);	/* dropped in usbatm_atm_dev_close */
933  
934  	/* ready for ATM callbacks */
935  	mb();
936  	atm_dev->dev_data = instance;
937  
938  	/* submit all rx URBs */
939  	for (i = 0; i < num_rcv_urbs; i++)
940  		usbatm_submit_urb(instance->urbs[i]);
941  
942  	return 0;
943  
944   fail:
945  	instance->atm_dev = NULL;
946  	atm_dev_deregister(atm_dev); /* usbatm_atm_dev_close will eventually be called */
947  	return ret;
948  }
949  
950  
951  /**********
952  **  USB  **
953  **********/
954  
usbatm_do_heavy_init(void * arg)955  static int usbatm_do_heavy_init(void *arg)
956  {
957  	struct usbatm_data *instance = arg;
958  	int ret;
959  
960  	allow_signal(SIGTERM);
961  	complete(&instance->thread_started);
962  
963  	ret = instance->driver->heavy_init(instance, instance->usb_intf);
964  
965  	if (!ret)
966  		ret = usbatm_atm_init(instance);
967  
968  	mutex_lock(&instance->serialize);
969  	instance->thread = NULL;
970  	mutex_unlock(&instance->serialize);
971  
972  	kthread_complete_and_exit(&instance->thread_exited, ret);
973  }
974  
usbatm_heavy_init(struct usbatm_data * instance)975  static int usbatm_heavy_init(struct usbatm_data *instance)
976  {
977  	struct task_struct *t;
978  
979  	t = kthread_create(usbatm_do_heavy_init, instance, "%s",
980  			instance->driver->driver_name);
981  	if (IS_ERR(t)) {
982  		usb_err(instance, "%s: failed to create kernel_thread (%ld)!\n",
983  				__func__, PTR_ERR(t));
984  		return PTR_ERR(t);
985  	}
986  
987  	instance->thread = t;
988  	wake_up_process(t);
989  	wait_for_completion(&instance->thread_started);
990  
991  	return 0;
992  }
993  
usbatm_tasklet_schedule(struct timer_list * t)994  static void usbatm_tasklet_schedule(struct timer_list *t)
995  {
996  	struct usbatm_channel *channel = timer_container_of(channel, t, delay);
997  
998  	tasklet_schedule(&channel->tasklet);
999  }
1000  
usbatm_init_channel(struct usbatm_channel * channel)1001  static void usbatm_init_channel(struct usbatm_channel *channel)
1002  {
1003  	spin_lock_init(&channel->lock);
1004  	INIT_LIST_HEAD(&channel->list);
1005  	timer_setup(&channel->delay, usbatm_tasklet_schedule, 0);
1006  }
1007  
usbatm_usb_probe(struct usb_interface * intf,const struct usb_device_id * id,struct usbatm_driver * driver)1008  int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id,
1009  		     struct usbatm_driver *driver)
1010  {
1011  	struct device *dev = &intf->dev;
1012  	struct usb_device *usb_dev = interface_to_usbdev(intf);
1013  	struct usbatm_data *instance;
1014  	char *buf;
1015  	int error = -ENOMEM;
1016  	int i, length;
1017  	unsigned int maxpacket, num_packets;
1018  	size_t size;
1019  
1020  	/* instance init */
1021  	size = struct_size(instance, urbs,
1022  			   size_add(num_rcv_urbs, num_snd_urbs));
1023  	instance = kzalloc(size, GFP_KERNEL);
1024  	if (!instance)
1025  		return -ENOMEM;
1026  
1027  	/* public fields */
1028  
1029  	instance->driver = driver;
1030  	strscpy(instance->driver_name, driver->driver_name,
1031  		sizeof(instance->driver_name));
1032  
1033  	instance->usb_dev = usb_dev;
1034  	instance->usb_intf = intf;
1035  
1036  	buf = instance->description;
1037  	length = sizeof(instance->description);
1038  
1039  	if ((i = usb_string(usb_dev, usb_dev->descriptor.iProduct, buf, length)) < 0)
1040  		goto bind;
1041  
1042  	buf += i;
1043  	length -= i;
1044  
1045  	i = scnprintf(buf, length, " (");
1046  	buf += i;
1047  	length -= i;
1048  
1049  	if (length <= 0 || (i = usb_make_path(usb_dev, buf, length)) < 0)
1050  		goto bind;
1051  
1052  	buf += i;
1053  	length -= i;
1054  
1055  	snprintf(buf, length, ")");
1056  
1057   bind:
1058  	if (driver->bind && (error = driver->bind(instance, intf, id)) < 0) {
1059  			dev_err(dev, "%s: bind failed: %d!\n", __func__, error);
1060  			goto fail_free;
1061  	}
1062  
1063  	/* private fields */
1064  
1065  	kref_init(&instance->refcount);		/* dropped in usbatm_usb_disconnect */
1066  	mutex_init(&instance->serialize);
1067  
1068  	instance->thread = NULL;
1069  	init_completion(&instance->thread_started);
1070  	init_completion(&instance->thread_exited);
1071  
1072  	INIT_LIST_HEAD(&instance->vcc_list);
1073  	skb_queue_head_init(&instance->sndqueue);
1074  
1075  	usbatm_init_channel(&instance->rx_channel);
1076  	usbatm_init_channel(&instance->tx_channel);
1077  	tasklet_setup(&instance->rx_channel.tasklet, usbatm_rx_process);
1078  	tasklet_setup(&instance->tx_channel.tasklet, usbatm_tx_process);
1079  	instance->rx_channel.stride = ATM_CELL_SIZE + driver->rx_padding;
1080  	instance->tx_channel.stride = ATM_CELL_SIZE + driver->tx_padding;
1081  	instance->rx_channel.usbatm = instance->tx_channel.usbatm = instance;
1082  
1083  	if ((instance->flags & UDSL_USE_ISOC) && driver->isoc_in)
1084  		instance->rx_channel.endpoint = usb_rcvisocpipe(usb_dev, driver->isoc_in);
1085  	else
1086  		instance->rx_channel.endpoint = usb_rcvbulkpipe(usb_dev, driver->bulk_in);
1087  
1088  	instance->tx_channel.endpoint = usb_sndbulkpipe(usb_dev, driver->bulk_out);
1089  
1090  	/* tx buffer size must be a positive multiple of the stride */
1091  	instance->tx_channel.buf_size = max(instance->tx_channel.stride,
1092  			snd_buf_bytes - (snd_buf_bytes % instance->tx_channel.stride));
1093  
1094  	/* rx buffer size must be a positive multiple of the endpoint maxpacket */
1095  	maxpacket = usb_maxpacket(usb_dev, instance->rx_channel.endpoint);
1096  
1097  	if ((maxpacket < 1) || (maxpacket > UDSL_MAX_BUF_SIZE)) {
1098  		dev_err(dev, "%s: invalid endpoint %02x!\n", __func__,
1099  				usb_pipeendpoint(instance->rx_channel.endpoint));
1100  		error = -EINVAL;
1101  		goto fail_unbind;
1102  	}
1103  
1104  	num_packets = max(1U, (rcv_buf_bytes + maxpacket / 2) / maxpacket); /* round */
1105  
1106  	if (num_packets * maxpacket > UDSL_MAX_BUF_SIZE)
1107  		num_packets--;
1108  
1109  	instance->rx_channel.buf_size = num_packets * maxpacket;
1110  	instance->rx_channel.packet_size = maxpacket;
1111  
1112  	for (i = 0; i < 2; i++) {
1113  		struct usbatm_channel *channel = i ?
1114  			&instance->tx_channel : &instance->rx_channel;
1115  
1116  		dev_dbg(dev, "%s: using %d byte buffer for %s channel 0x%p\n",
1117  			__func__, channel->buf_size, i ? "tx" : "rx", channel);
1118  	}
1119  
1120  	/* initialize urbs */
1121  
1122  	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1123  		u8 *buffer;
1124  		struct usbatm_channel *channel = i < num_rcv_urbs ?
1125  			&instance->rx_channel : &instance->tx_channel;
1126  		struct urb *urb;
1127  		unsigned int iso_packets = usb_pipeisoc(channel->endpoint) ? channel->buf_size / channel->packet_size : 0;
1128  
1129  		urb = usb_alloc_urb(iso_packets, GFP_KERNEL);
1130  		if (!urb) {
1131  			error = -ENOMEM;
1132  			goto fail_unbind;
1133  		}
1134  
1135  		instance->urbs[i] = urb;
1136  
1137  		/* zero the tx padding to avoid leaking information */
1138  		buffer = kzalloc(channel->buf_size, GFP_KERNEL);
1139  		if (!buffer) {
1140  			error = -ENOMEM;
1141  			goto fail_unbind;
1142  		}
1143  
1144  		usb_fill_bulk_urb(urb, instance->usb_dev, channel->endpoint,
1145  				  buffer, channel->buf_size, usbatm_complete, channel);
1146  		if (iso_packets) {
1147  			int j;
1148  			urb->interval = 1;
1149  			urb->transfer_flags = URB_ISO_ASAP;
1150  			urb->number_of_packets = iso_packets;
1151  			for (j = 0; j < iso_packets; j++) {
1152  				urb->iso_frame_desc[j].offset = channel->packet_size * j;
1153  				urb->iso_frame_desc[j].length = channel->packet_size;
1154  			}
1155  		}
1156  
1157  		/* put all tx URBs on the list of spares */
1158  		if (i >= num_rcv_urbs)
1159  			list_add_tail(&urb->urb_list, &channel->list);
1160  
1161  		vdbg(&intf->dev, "%s: allocated buffer 0x%p buf size %u urb 0x%p",
1162  		     __func__, urb->transfer_buffer, urb->transfer_buffer_length, urb);
1163  	}
1164  
1165  	instance->cached_vpi = ATM_VPI_UNSPEC;
1166  	instance->cached_vci = ATM_VCI_UNSPEC;
1167  	instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL);
1168  
1169  	if (!instance->cell_buf) {
1170  		error = -ENOMEM;
1171  		goto fail_unbind;
1172  	}
1173  
1174  	if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) {
1175  		error = usbatm_heavy_init(instance);
1176  	} else {
1177  		complete(&instance->thread_exited);	/* pretend that heavy_init was run */
1178  		error = usbatm_atm_init(instance);
1179  	}
1180  
1181  	if (error < 0)
1182  		goto fail_unbind;
1183  
1184  	usb_get_dev(usb_dev);
1185  	usb_set_intfdata(intf, instance);
1186  
1187  	return 0;
1188  
1189   fail_unbind:
1190  	if (instance->driver->unbind)
1191  		instance->driver->unbind(instance, intf);
1192   fail_free:
1193  	kfree(instance->cell_buf);
1194  
1195  	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1196  		if (instance->urbs[i])
1197  			kfree(instance->urbs[i]->transfer_buffer);
1198  		usb_free_urb(instance->urbs[i]);
1199  	}
1200  
1201  	kfree(instance);
1202  
1203  	return error;
1204  }
1205  EXPORT_SYMBOL_GPL(usbatm_usb_probe);
1206  
usbatm_usb_disconnect(struct usb_interface * intf)1207  void usbatm_usb_disconnect(struct usb_interface *intf)
1208  {
1209  	struct device *dev = &intf->dev;
1210  	struct usbatm_data *instance = usb_get_intfdata(intf);
1211  	struct usbatm_vcc_data *vcc_data;
1212  	int i;
1213  
1214  	if (!instance) {
1215  		dev_dbg(dev, "%s: NULL instance!\n", __func__);
1216  		return;
1217  	}
1218  
1219  	usb_set_intfdata(intf, NULL);
1220  
1221  	mutex_lock(&instance->serialize);
1222  	instance->disconnected = 1;
1223  	if (instance->thread != NULL)
1224  		send_sig(SIGTERM, instance->thread, 1);
1225  	mutex_unlock(&instance->serialize);
1226  
1227  	wait_for_completion(&instance->thread_exited);
1228  
1229  	mutex_lock(&instance->serialize);
1230  	list_for_each_entry(vcc_data, &instance->vcc_list, list)
1231  		vcc_release_async(vcc_data->vcc, -EPIPE);
1232  	mutex_unlock(&instance->serialize);
1233  
1234  	tasklet_disable(&instance->rx_channel.tasklet);
1235  	tasklet_disable(&instance->tx_channel.tasklet);
1236  
1237  	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++)
1238  		usb_kill_urb(instance->urbs[i]);
1239  
1240  	timer_delete_sync(&instance->rx_channel.delay);
1241  	timer_delete_sync(&instance->tx_channel.delay);
1242  
1243  	/* turn usbatm_[rt]x_process into something close to a no-op */
1244  	/* no need to take the spinlock */
1245  	INIT_LIST_HEAD(&instance->rx_channel.list);
1246  	INIT_LIST_HEAD(&instance->tx_channel.list);
1247  
1248  	tasklet_enable(&instance->rx_channel.tasklet);
1249  	tasklet_enable(&instance->tx_channel.tasklet);
1250  
1251  	if (instance->atm_dev && instance->driver->atm_stop)
1252  		instance->driver->atm_stop(instance, instance->atm_dev);
1253  
1254  	if (instance->driver->unbind)
1255  		instance->driver->unbind(instance, intf);
1256  
1257  	instance->driver_data = NULL;
1258  
1259  	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1260  		kfree(instance->urbs[i]->transfer_buffer);
1261  		usb_free_urb(instance->urbs[i]);
1262  	}
1263  
1264  	kfree(instance->cell_buf);
1265  
1266  	/* ATM finalize */
1267  	if (instance->atm_dev) {
1268  		atm_dev_deregister(instance->atm_dev);
1269  		instance->atm_dev = NULL;
1270  	}
1271  
1272  	usbatm_put_instance(instance);	/* taken in usbatm_usb_probe */
1273  }
1274  EXPORT_SYMBOL_GPL(usbatm_usb_disconnect);
1275  
1276  
1277  /***********
1278  **  init  **
1279  ***********/
1280  
usbatm_usb_init(void)1281  static int __init usbatm_usb_init(void)
1282  {
1283  	if (sizeof(struct usbatm_control) > sizeof_field(struct sk_buff, cb)) {
1284  		pr_err("%s unusable with this kernel!\n", usbatm_driver_name);
1285  		return -EIO;
1286  	}
1287  
1288  	if ((num_rcv_urbs > UDSL_MAX_RCV_URBS)
1289  	    || (num_snd_urbs > UDSL_MAX_SND_URBS)
1290  	    || (rcv_buf_bytes < 1)
1291  	    || (rcv_buf_bytes > UDSL_MAX_BUF_SIZE)
1292  	    || (snd_buf_bytes < 1)
1293  	    || (snd_buf_bytes > UDSL_MAX_BUF_SIZE))
1294  		return -EINVAL;
1295  
1296  	return 0;
1297  }
1298  module_init(usbatm_usb_init);
1299  
usbatm_usb_exit(void)1300  static void __exit usbatm_usb_exit(void)
1301  {
1302  }
1303  module_exit(usbatm_usb_exit);
1304  
1305  MODULE_AUTHOR(DRIVER_AUTHOR);
1306  MODULE_DESCRIPTION(DRIVER_DESC);
1307  MODULE_LICENSE("GPL");
1308  
1309  /************
1310  **  debug  **
1311  ************/
1312  
1313  #ifdef VERBOSE_DEBUG
usbatm_print_packet(struct usbatm_data * instance,const unsigned char * data,int len)1314  static int usbatm_print_packet(struct usbatm_data *instance,
1315  			       const unsigned char *data, int len)
1316  {
1317  	unsigned char buffer[256];
1318  	int i = 0, j = 0;
1319  
1320  	for (i = 0; i < len;) {
1321  		buffer[0] = '\0';
1322  		sprintf(buffer, "%.3d :", i);
1323  		for (j = 0; (j < 16) && (i < len); j++, i++)
1324  			sprintf(buffer, "%s %2.2x", buffer, data[i]);
1325  		dev_dbg(&instance->usb_intf->dev, "%s", buffer);
1326  	}
1327  	return i;
1328  }
1329  #endif
1330