aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/char/pcmcia/ipwireless/network.c
blob: 2b07af05106d1a39cb9821d240fa155189f25b76 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
/*
 * IPWireless 3G PCMCIA Network Driver
 *
 * Original code
 *   by Stephen Blackheath <stephen@blacksapphire.com>,
 *      Ben Martel <benm@symmetric.co.nz>
 *
 * Copyrighted as follows:
 *   Copyright (C) 2004 by Symmetric Systems Ltd (NZ)
 *
 * Various driver changes and rewrites, port to new kernels
 *   Copyright (C) 2006-2007 Jiri Kosina
 *
 * Misc code cleanups and updates
 *   Copyright (C) 2007 David Sterba
 */

#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/ppp_channel.h>
#include <linux/ppp_defs.h>
#include <linux/if_ppp.h>
#include <linux/skbuff.h>

#include "network.h"
#include "hardware.h"
#include "main.h"
#include "tty.h"

#define MAX_ASSOCIATED_TTYS 2

#define SC_RCV_BITS     (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)

struct ipw_network {
	/* Hardware context, used for calls to hardware layer. */
	struct ipw_hardware *hardware;
	/* Context for kernel 'generic_ppp' functionality */
	struct ppp_channel *ppp_channel;
	/* tty context connected with IPW console */
	struct ipw_tty *associated_ttys[NO_OF_IPW_CHANNELS][MAX_ASSOCIATED_TTYS];
	/* True if ppp needs waking up once we're ready to xmit */
	int ppp_blocked;
	/* Number of packets queued up in hardware module. */
	int outgoing_packets_queued;
	/* Spinlock to avoid interrupts during shutdown */
	spinlock_t lock;
	struct mutex close_lock;

	/* PPP ioctl data, not actually used anywere */
	unsigned int flags;
	unsigned int rbits;
	u32 xaccm[8];
	u32 raccm;
	int mru;

	int shutting_down;
	unsigned int ras_control_lines;

	struct work_struct work_go_online;
	struct work_struct work_go_offline;
};

static void notify_packet_sent(void *callback_data, unsigned int packet_length)
{
	struct ipw_network *network = callback_data;
	unsigned long flags;

	spin_lock_irqsave(&network->lock, flags);
	network->outgoing_packets_queued--;
	if (network->ppp_channel != NULL) {
		if (network->ppp_blocked) {
			network->ppp_blocked = 0;
			spin_unlock_irqrestore(&network->lock, flags);
			ppp_output_wakeup(network->ppp_channel);
			if (ipwireless_debug)
				printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME
				       ": ppp unblocked\n");
		} else
			spin_unlock_irqrestore(&network->lock, flags);
	} else
		spin_unlock_irqrestore(&network->lock, flags);
}

/*
 * Called by the ppp system when it has a packet to send to the hardware.
 */
static int ipwireless_ppp_start_xmit(struct ppp_channel *ppp_channel,
				     struct sk_buff *skb)
{
	struct ipw_network *network = ppp_channel->private;
	unsigned long flags;

	spin_lock_irqsave(&network->lock, flags);
	if (network->outgoing_packets_queued < ipwireless_out_queue) {
		unsigned char *buf;
		static unsigned char header[] = {
			PPP_ALLSTATIONS, /* 0xff */
			PPP_UI,		 /* 0x03 */
		};
		int ret;

		network->outgoing_packets_queued++;
		spin_unlock_irqrestore(&network->lock, flags);

		/*
		 * If we have the requested amount of headroom in the skb we
		 * were handed, then we can add the header efficiently.
		 */
		if (skb_headroom(skb) >= 2) {
			memcpy(skb_push(skb, 2), header, 2);
			ret = ipwireless_send_packet(network->hardware,
					       IPW_CHANNEL_RAS, skb->data,
					       skb->len,
					       notify_packet_sent,
					       network);
			if (ret == -1) {
				skb_pull(skb, 2);
				return 0;
			}
		} else {
			/* Otherwise (rarely) we do it inefficiently. */
			buf = kmalloc(skb->len + 2, GFP_ATOMIC);
			if (!buf)
				return 0;
			memcpy(buf + 2, skb->data, skb->len);
			memcpy(buf, header, 2);
			ret = ipwireless_send_packet(network->hardware,
					       IPW_CHANNEL_RAS, buf,
					       skb->len + 2,
					       notify_packet_sent,
					       network);
			kfree(buf);
			if (ret == -1)
				return 0;
		}
		kfree_skb(skb);
		return 1;
	} else {
		/*
		 * Otherwise reject the packet, and flag that the ppp system
		 * needs to be unblocked once we are ready to send.
		 */
		network->ppp_blocked = 1;
		spin_unlock_irqrestore(&network->lock, flags);
		if (ipwireless_debug)
			printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": ppp blocked\n");
		return 0;
	}
}

/* Handle an ioctl call that has come in via ppp. (copy of ppp_async_ioctl() */
static int ipwireless_ppp_ioctl(struct ppp_channel *ppp_channel,
				unsigned int cmd, unsigned long arg)
{
	struct ipw_network *network = ppp_channel->private;
	int err, val;
	u32 accm[8];
	int __user *user_arg = (int __user *) arg;

	err = -EFAULT;
	switch (cmd) {
	case PPPIOCGFLAGS:
		val = network->flags | network->rbits;
		if (put_user(val, user_arg))
			break;
		err = 0;
		break;

	case PPPIOCSFLAGS:
		if (get_user(val, user_arg))
			break;
		network->flags = val & ~SC_RCV_BITS;
		network->rbits = val & SC_RCV_BITS;
		err = 0;
		break;

	case PPPIOCGASYNCMAP:
		if (put_user(network->xaccm[0], user_arg))
			break;
		err = 0;
		break;

	case PPPIOCSASYNCMAP:
		if (get_user(network->xaccm[0], user_arg))
			break;
		err = 0;
		break;

	case PPPIOCGRASYNCMAP:
		if (put_user(network->raccm, user_arg))
			break;
		err = 0;
		break;

	case PPPIOCSRASYNCMAP:
		if (get_user(network->raccm, user_arg))
			break;
		err = 0;
		break;

	case PPPIOCGXASYNCMAP:
		if (copy_to_user((void __user *) arg, network->xaccm,
					sizeof(network->xaccm)))
			break;
		err = 0;
		break;

	case PPPIOCSXASYNCMAP:
		if (copy_from_user(accm, (void __user *) arg, sizeof(accm)))
			break;
		accm[2] &= ~0x40000000U;	/* can't escape 0x5e */
		accm[3] |= 0x60000000U;	/* must escape 0x7d, 0x7e */
		memcpy(network->xaccm, accm, sizeof(network->xaccm));
		err = 0;
		break;

	case PPPIOCGMRU:
		if (put_user(network->mru, user_arg))
			break;
		err = 0;
		break;

	case PPPIOCSMRU:
		if (get_user(val, user_arg))
			break;
		if (val < PPP_MRU)
			val = PPP_MRU;
		network->mru = val;
		err = 0;
		break;

	default:
		err = -ENOTTY;
	}

	return err;
}

static struct ppp_channel_ops ipwireless_ppp_channel_ops = {
	.start_xmit = ipwireless_ppp_start_xmit,
	.ioctl      = ipwireless_ppp_ioctl
};

static void do_go_online(struct work_struct *work_go_online)
{
	struct ipw_network *network =
		container_of(work_go_online, struct ipw_network,
				work_go_online);
	unsigned long flags;

	spin_lock_irqsave(&network->lock, flags);
	if (!network->ppp_channel) {
		struct ppp_channel *channel;

		spin_unlock_irqrestore(&network->lock, flags);
		channel = kzalloc(sizeof(struct ppp_channel), GFP_KERNEL);
		if (!channel) {
			printk(KERN_ERR IPWIRELESS_PCCARD_NAME
					": unable to allocate PPP channel\n");
			return;
		}
		channel->private = network;
		channel->mtu = 16384;	/* Wild guess */
		channel->hdrlen = 2;
		channel->ops = &ipwireless_ppp_channel_ops;

		network->flags = 0;
		network->rbits = 0;
		network->mru = PPP_MRU;
		memset(network->xaccm, 0, sizeof(network->xaccm));
		network->xaccm[0] = ~0U;
		network->xaccm[3] = 0x60000000U;
		network->raccm = ~0U;
		ppp_register_channel(channel);
		spin_lock_irqsave(&network->lock, flags);
		network->ppp_channel = channel;
	}
	spin_unlock_irqrestore(&network->lock, flags);
}

static void do_go_offline(struct work_struct *work_go_offline)
{
	struct ipw_network *network =
		container_of(work_go_offline, struct ipw_network,
				work_go_offline);
	unsigned long flags;

	mutex_lock(&network->close_lock);
	spin_lock_irqsave(&network->lock, flags);
	if (network->ppp_channel != NULL) {
		struct ppp_channel *channel = network->ppp_channel;

		network->ppp_channel = NULL;
		spin_unlock_irqrestore(&network->lock, flags);
		mutex_unlock(&network->close_lock);
		ppp_unregister_channel(channel);
	} else {
		spin_unlock_irqrestore(&network->lock, flags);
		mutex_unlock(&network->close_lock);
	}
}

void ipwireless_network_notify_control_line_change(struct ipw_network *network,
						   unsigned int channel_idx,
						   unsigned int control_lines,
						   unsigned int changed_mask)
{
	int i;

	if (channel_idx == IPW_CHANNEL_RAS)
		network->ras_control_lines = control_lines;

	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
		struct ipw_tty *tty =
			network->associated_ttys[channel_idx][i];

		/*
		 * If it's associated with a tty (other than the RAS channel
		 * when we're online), then send the data to that tty.  The RAS
		 * channel's data is handled above - it always goes through
		 * ppp_generic.
		 */
		if (tty)
			ipwireless_tty_notify_control_line_change(tty,
								  channel_idx,
								  control_lines,
								  changed_mask);
	}
}

/*
 * Some versions of firmware stuff packets with 0xff 0x03 (PPP: ALLSTATIONS, UI)
 * bytes, which are required on sent packet, but not always present on received
 * packets
 */
static struct sk_buff *ipw_packet_received_skb(unsigned char *data,
					       unsigned int length)
{
	struct sk_buff *skb;

	if (length > 2 && data[0] == PPP_ALLSTATIONS && data[1] == PPP_UI) {
		length -= 2;
		data += 2;
	}

	skb = dev_alloc_skb(length + 4);
	skb_reserve(skb, 2);
	memcpy(skb_put(skb, length), data, length);

	return skb;
}

void ipwireless_network_packet_received(struct ipw_network *network,
					unsigned int channel_idx,
					unsigned char *data,
					unsigned int length)
{
	int i;
	unsigned long flags;

	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
		struct ipw_tty *tty = network->associated_ttys[channel_idx][i];

		if (!tty)
			continue;

		/*
		 * If it's associated with a tty (other than the RAS channel
		 * when we're online), then send the data to that tty.  The RAS
		 * channel's data is handled above - it always goes through
		 * ppp_generic.
		 */
		if (channel_idx == IPW_CHANNEL_RAS
				&& (network->ras_control_lines &
					IPW_CONTROL_LINE_DCD) != 0
				&& ipwireless_tty_is_modem(tty)) {
			/*
			 * If data came in on the RAS channel and this tty is
			 * the modem tty, and we are online, then we send it to
			 * the PPP layer.
			 */
			mutex_lock(&network->close_lock);
			spin_lock_irqsave(&network->lock, flags);
			if (network->ppp_channel != NULL) {
				struct sk_buff *skb;

				spin_unlock_irqrestore(&network->lock,
						flags);

				/* Send the data to the ppp_generic module. */
				skb = ipw_packet_received_skb(data, length);
				ppp_input(network->ppp_channel, skb);
			} else
				spin_unlock_irqrestore(&network->lock,
						flags);
			mutex_unlock(&network->close_lock);
		}
		/* Otherwise we send it out the tty. */
		else
			ipwireless_tty_received(tty, data, length);
	}
}

struct ipw_network *ipwireless_network_create(struct ipw_hardware *hw)
{
	struct ipw_network *network =
		kzalloc(sizeof(struct ipw_network), GFP_ATOMIC);

	if (!network)
		return NULL;

	spin_lock_init(&network->lock);
	mutex_init(&network->close_lock);

	network->hardware = hw;

	INIT_WORK(&network->work_go_online, do_go_online);
	INIT_WORK(&network->work_go_offline, do_go_offline);

	ipwireless_associate_network(hw, network);

	return network;
}

void ipwireless_network_free(struct ipw_network *network)
{
	network->shutting_down = 1;

	ipwireless_ppp_close(network);
	flush_scheduled_work();

	ipwireless_stop_interrupts(network->hardware);
	ipwireless_associate_network(network->hardware, NULL);

	kfree(network);
}

void ipwireless_associate_network_tty(struct ipw_network *network,
				      unsigned int channel_idx,
				      struct ipw_tty *tty)
{
	int i;

	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
		if (network->associated_ttys[channel_idx][i] == NULL) {
			network->associated_ttys[channel_idx][i] = tty;
			break;
		}
}

void ipwireless_disassociate_network_ttys(struct ipw_network *network,
					  unsigned int channel_idx)
{
	int i;

	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
		network->associated_ttys[channel_idx][i] = NULL;
}

void ipwireless_ppp_open(struct ipw_network *network)
{
	if (ipwireless_debug)
		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": online\n");
	schedule_work(&network->work_go_online);
}

void ipwireless_ppp_close(struct ipw_network *network)
{
	/* Disconnect from the wireless network. */
	if (ipwireless_debug)
		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": offline\n");
	schedule_work(&network->work_go_offline);
}

int ipwireless_ppp_channel_index(struct ipw_network *network)
{
	int ret = -1;
	unsigned long flags;

	spin_lock_irqsave(&network->lock, flags);
	if (network->ppp_channel != NULL)
		ret = ppp_channel_index(network->ppp_channel);
	spin_unlock_irqrestore(&network->lock, flags);

	return ret;
}

int ipwireless_ppp_unit_number(struct ipw_network *network)
{
	int ret = -1;
	unsigned long flags;

	spin_lock_irqsave(&network->lock, flags);
	if (network->ppp_channel != NULL)
		ret = ppp_unit_number(network->ppp_channel);
	spin_unlock_irqrestore(&network->lock, flags);

	return ret;
}