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/drivers/tty/ipwireless/network.c

http://github.com/mirrors/linux
C | 517 lines | 382 code | 73 blank | 62 comment | 64 complexity | 23b7475c7e831578cf73f727d7f819b5 MD5 | raw file
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * IPWireless 3G PCMCIA Network Driver
  4 *
  5 * Original code
  6 *   by Stephen Blackheath <stephen@blacksapphire.com>,
  7 *      Ben Martel <benm@symmetric.co.nz>
  8 *
  9 * Copyrighted as follows:
 10 *   Copyright (C) 2004 by Symmetric Systems Ltd (NZ)
 11 *
 12 * Various driver changes and rewrites, port to new kernels
 13 *   Copyright (C) 2006-2007 Jiri Kosina
 14 *
 15 * Misc code cleanups and updates
 16 *   Copyright (C) 2007 David Sterba
 17 */
 18
 19#include <linux/interrupt.h>
 20#include <linux/kernel.h>
 21#include <linux/mutex.h>
 22#include <linux/netdevice.h>
 23#include <linux/ppp_channel.h>
 24#include <linux/ppp_defs.h>
 25#include <linux/slab.h>
 26#include <linux/ppp-ioctl.h>
 27#include <linux/skbuff.h>
 28
 29#include "network.h"
 30#include "hardware.h"
 31#include "main.h"
 32#include "tty.h"
 33
 34#define MAX_ASSOCIATED_TTYS 2
 35
 36#define SC_RCV_BITS     (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
 37
 38struct ipw_network {
 39	/* Hardware context, used for calls to hardware layer. */
 40	struct ipw_hardware *hardware;
 41	/* Context for kernel 'generic_ppp' functionality */
 42	struct ppp_channel *ppp_channel;
 43	/* tty context connected with IPW console */
 44	struct ipw_tty *associated_ttys[NO_OF_IPW_CHANNELS][MAX_ASSOCIATED_TTYS];
 45	/* True if ppp needs waking up once we're ready to xmit */
 46	int ppp_blocked;
 47	/* Number of packets queued up in hardware module. */
 48	int outgoing_packets_queued;
 49	/* Spinlock to avoid interrupts during shutdown */
 50	spinlock_t lock;
 51	struct mutex close_lock;
 52
 53	/* PPP ioctl data, not actually used anywere */
 54	unsigned int flags;
 55	unsigned int rbits;
 56	u32 xaccm[8];
 57	u32 raccm;
 58	int mru;
 59
 60	int shutting_down;
 61	unsigned int ras_control_lines;
 62
 63	struct work_struct work_go_online;
 64	struct work_struct work_go_offline;
 65};
 66
 67static void notify_packet_sent(void *callback_data, unsigned int packet_length)
 68{
 69	struct ipw_network *network = callback_data;
 70	unsigned long flags;
 71
 72	spin_lock_irqsave(&network->lock, flags);
 73	network->outgoing_packets_queued--;
 74	if (network->ppp_channel != NULL) {
 75		if (network->ppp_blocked) {
 76			network->ppp_blocked = 0;
 77			spin_unlock_irqrestore(&network->lock, flags);
 78			ppp_output_wakeup(network->ppp_channel);
 79			if (ipwireless_debug)
 80				printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME
 81				       ": ppp unblocked\n");
 82		} else
 83			spin_unlock_irqrestore(&network->lock, flags);
 84	} else
 85		spin_unlock_irqrestore(&network->lock, flags);
 86}
 87
 88/*
 89 * Called by the ppp system when it has a packet to send to the hardware.
 90 */
 91static int ipwireless_ppp_start_xmit(struct ppp_channel *ppp_channel,
 92				     struct sk_buff *skb)
 93{
 94	struct ipw_network *network = ppp_channel->private;
 95	unsigned long flags;
 96
 97	spin_lock_irqsave(&network->lock, flags);
 98	if (network->outgoing_packets_queued < ipwireless_out_queue) {
 99		unsigned char *buf;
100		static unsigned char header[] = {
101			PPP_ALLSTATIONS, /* 0xff */
102			PPP_UI,		 /* 0x03 */
103		};
104		int ret;
105
106		network->outgoing_packets_queued++;
107		spin_unlock_irqrestore(&network->lock, flags);
108
109		/*
110		 * If we have the requested amount of headroom in the skb we
111		 * were handed, then we can add the header efficiently.
112		 */
113		if (skb_headroom(skb) >= 2) {
114			memcpy(skb_push(skb, 2), header, 2);
115			ret = ipwireless_send_packet(network->hardware,
116					       IPW_CHANNEL_RAS, skb->data,
117					       skb->len,
118					       notify_packet_sent,
119					       network);
120			if (ret == -1) {
121				skb_pull(skb, 2);
122				return 0;
123			}
124		} else {
125			/* Otherwise (rarely) we do it inefficiently. */
126			buf = kmalloc(skb->len + 2, GFP_ATOMIC);
127			if (!buf)
128				return 0;
129			memcpy(buf + 2, skb->data, skb->len);
130			memcpy(buf, header, 2);
131			ret = ipwireless_send_packet(network->hardware,
132					       IPW_CHANNEL_RAS, buf,
133					       skb->len + 2,
134					       notify_packet_sent,
135					       network);
136			kfree(buf);
137			if (ret == -1)
138				return 0;
139		}
140		kfree_skb(skb);
141		return 1;
142	} else {
143		/*
144		 * Otherwise reject the packet, and flag that the ppp system
145		 * needs to be unblocked once we are ready to send.
146		 */
147		network->ppp_blocked = 1;
148		spin_unlock_irqrestore(&network->lock, flags);
149		if (ipwireless_debug)
150			printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": ppp blocked\n");
151		return 0;
152	}
153}
154
155/* Handle an ioctl call that has come in via ppp. (copy of ppp_async_ioctl() */
156static int ipwireless_ppp_ioctl(struct ppp_channel *ppp_channel,
157				unsigned int cmd, unsigned long arg)
158{
159	struct ipw_network *network = ppp_channel->private;
160	int err, val;
161	u32 accm[8];
162	int __user *user_arg = (int __user *) arg;
163
164	err = -EFAULT;
165	switch (cmd) {
166	case PPPIOCGFLAGS:
167		val = network->flags | network->rbits;
168		if (put_user(val, user_arg))
169			break;
170		err = 0;
171		break;
172
173	case PPPIOCSFLAGS:
174		if (get_user(val, user_arg))
175			break;
176		network->flags = val & ~SC_RCV_BITS;
177		network->rbits = val & SC_RCV_BITS;
178		err = 0;
179		break;
180
181	case PPPIOCGASYNCMAP:
182		if (put_user(network->xaccm[0], user_arg))
183			break;
184		err = 0;
185		break;
186
187	case PPPIOCSASYNCMAP:
188		if (get_user(network->xaccm[0], user_arg))
189			break;
190		err = 0;
191		break;
192
193	case PPPIOCGRASYNCMAP:
194		if (put_user(network->raccm, user_arg))
195			break;
196		err = 0;
197		break;
198
199	case PPPIOCSRASYNCMAP:
200		if (get_user(network->raccm, user_arg))
201			break;
202		err = 0;
203		break;
204
205	case PPPIOCGXASYNCMAP:
206		if (copy_to_user((void __user *) arg, network->xaccm,
207					sizeof(network->xaccm)))
208			break;
209		err = 0;
210		break;
211
212	case PPPIOCSXASYNCMAP:
213		if (copy_from_user(accm, (void __user *) arg, sizeof(accm)))
214			break;
215		accm[2] &= ~0x40000000U;	/* can't escape 0x5e */
216		accm[3] |= 0x60000000U;	/* must escape 0x7d, 0x7e */
217		memcpy(network->xaccm, accm, sizeof(network->xaccm));
218		err = 0;
219		break;
220
221	case PPPIOCGMRU:
222		if (put_user(network->mru, user_arg))
223			break;
224		err = 0;
225		break;
226
227	case PPPIOCSMRU:
228		if (get_user(val, user_arg))
229			break;
230		if (val < PPP_MRU)
231			val = PPP_MRU;
232		network->mru = val;
233		err = 0;
234		break;
235
236	default:
237		err = -ENOTTY;
238	}
239
240	return err;
241}
242
243static const struct ppp_channel_ops ipwireless_ppp_channel_ops = {
244	.start_xmit = ipwireless_ppp_start_xmit,
245	.ioctl      = ipwireless_ppp_ioctl
246};
247
248static void do_go_online(struct work_struct *work_go_online)
249{
250	struct ipw_network *network =
251		container_of(work_go_online, struct ipw_network,
252				work_go_online);
253	unsigned long flags;
254
255	spin_lock_irqsave(&network->lock, flags);
256	if (!network->ppp_channel) {
257		struct ppp_channel *channel;
258
259		spin_unlock_irqrestore(&network->lock, flags);
260		channel = kzalloc(sizeof(struct ppp_channel), GFP_KERNEL);
261		if (!channel) {
262			printk(KERN_ERR IPWIRELESS_PCCARD_NAME
263					": unable to allocate PPP channel\n");
264			return;
265		}
266		channel->private = network;
267		channel->mtu = 16384;	/* Wild guess */
268		channel->hdrlen = 2;
269		channel->ops = &ipwireless_ppp_channel_ops;
270
271		network->flags = 0;
272		network->rbits = 0;
273		network->mru = PPP_MRU;
274		memset(network->xaccm, 0, sizeof(network->xaccm));
275		network->xaccm[0] = ~0U;
276		network->xaccm[3] = 0x60000000U;
277		network->raccm = ~0U;
278		if (ppp_register_channel(channel) < 0) {
279			printk(KERN_ERR IPWIRELESS_PCCARD_NAME
280					": unable to register PPP channel\n");
281			kfree(channel);
282			return;
283		}
284		spin_lock_irqsave(&network->lock, flags);
285		network->ppp_channel = channel;
286	}
287	spin_unlock_irqrestore(&network->lock, flags);
288}
289
290static void do_go_offline(struct work_struct *work_go_offline)
291{
292	struct ipw_network *network =
293		container_of(work_go_offline, struct ipw_network,
294				work_go_offline);
295	unsigned long flags;
296
297	mutex_lock(&network->close_lock);
298	spin_lock_irqsave(&network->lock, flags);
299	if (network->ppp_channel != NULL) {
300		struct ppp_channel *channel = network->ppp_channel;
301
302		network->ppp_channel = NULL;
303		spin_unlock_irqrestore(&network->lock, flags);
304		mutex_unlock(&network->close_lock);
305		ppp_unregister_channel(channel);
306	} else {
307		spin_unlock_irqrestore(&network->lock, flags);
308		mutex_unlock(&network->close_lock);
309	}
310}
311
312void ipwireless_network_notify_control_line_change(struct ipw_network *network,
313						   unsigned int channel_idx,
314						   unsigned int control_lines,
315						   unsigned int changed_mask)
316{
317	int i;
318
319	if (channel_idx == IPW_CHANNEL_RAS)
320		network->ras_control_lines = control_lines;
321
322	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
323		struct ipw_tty *tty =
324			network->associated_ttys[channel_idx][i];
325
326		/*
327		 * If it's associated with a tty (other than the RAS channel
328		 * when we're online), then send the data to that tty.  The RAS
329		 * channel's data is handled above - it always goes through
330		 * ppp_generic.
331		 */
332		if (tty)
333			ipwireless_tty_notify_control_line_change(tty,
334								  channel_idx,
335								  control_lines,
336								  changed_mask);
337	}
338}
339
340/*
341 * Some versions of firmware stuff packets with 0xff 0x03 (PPP: ALLSTATIONS, UI)
342 * bytes, which are required on sent packet, but not always present on received
343 * packets
344 */
345static struct sk_buff *ipw_packet_received_skb(unsigned char *data,
346					       unsigned int length)
347{
348	struct sk_buff *skb;
349
350	if (length > 2 && data[0] == PPP_ALLSTATIONS && data[1] == PPP_UI) {
351		length -= 2;
352		data += 2;
353	}
354
355	skb = dev_alloc_skb(length + 4);
356	if (skb == NULL)
357		return NULL;
358	skb_reserve(skb, 2);
359	skb_put_data(skb, data, length);
360
361	return skb;
362}
363
364void ipwireless_network_packet_received(struct ipw_network *network,
365					unsigned int channel_idx,
366					unsigned char *data,
367					unsigned int length)
368{
369	int i;
370	unsigned long flags;
371
372	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
373		struct ipw_tty *tty = network->associated_ttys[channel_idx][i];
374
375		if (!tty)
376			continue;
377
378		/*
379		 * If it's associated with a tty (other than the RAS channel
380		 * when we're online), then send the data to that tty.  The RAS
381		 * channel's data is handled above - it always goes through
382		 * ppp_generic.
383		 */
384		if (channel_idx == IPW_CHANNEL_RAS
385				&& (network->ras_control_lines &
386					IPW_CONTROL_LINE_DCD) != 0
387				&& ipwireless_tty_is_modem(tty)) {
388			/*
389			 * If data came in on the RAS channel and this tty is
390			 * the modem tty, and we are online, then we send it to
391			 * the PPP layer.
392			 */
393			mutex_lock(&network->close_lock);
394			spin_lock_irqsave(&network->lock, flags);
395			if (network->ppp_channel != NULL) {
396				struct sk_buff *skb;
397
398				spin_unlock_irqrestore(&network->lock,
399						flags);
400
401				/* Send the data to the ppp_generic module. */
402				skb = ipw_packet_received_skb(data, length);
403				if (skb)
404					ppp_input(network->ppp_channel, skb);
405			} else
406				spin_unlock_irqrestore(&network->lock,
407						flags);
408			mutex_unlock(&network->close_lock);
409		}
410		/* Otherwise we send it out the tty. */
411		else
412			ipwireless_tty_received(tty, data, length);
413	}
414}
415
416struct ipw_network *ipwireless_network_create(struct ipw_hardware *hw)
417{
418	struct ipw_network *network =
419		kzalloc(sizeof(struct ipw_network), GFP_KERNEL);
420
421	if (!network)
422		return NULL;
423
424	spin_lock_init(&network->lock);
425	mutex_init(&network->close_lock);
426
427	network->hardware = hw;
428
429	INIT_WORK(&network->work_go_online, do_go_online);
430	INIT_WORK(&network->work_go_offline, do_go_offline);
431
432	ipwireless_associate_network(hw, network);
433
434	return network;
435}
436
437void ipwireless_network_free(struct ipw_network *network)
438{
439	network->shutting_down = 1;
440
441	ipwireless_ppp_close(network);
442	flush_work(&network->work_go_online);
443	flush_work(&network->work_go_offline);
444
445	ipwireless_stop_interrupts(network->hardware);
446	ipwireless_associate_network(network->hardware, NULL);
447
448	kfree(network);
449}
450
451void ipwireless_associate_network_tty(struct ipw_network *network,
452				      unsigned int channel_idx,
453				      struct ipw_tty *tty)
454{
455	int i;
456
457	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
458		if (network->associated_ttys[channel_idx][i] == NULL) {
459			network->associated_ttys[channel_idx][i] = tty;
460			break;
461		}
462}
463
464void ipwireless_disassociate_network_ttys(struct ipw_network *network,
465					  unsigned int channel_idx)
466{
467	int i;
468
469	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
470		network->associated_ttys[channel_idx][i] = NULL;
471}
472
473void ipwireless_ppp_open(struct ipw_network *network)
474{
475	if (ipwireless_debug)
476		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": online\n");
477	schedule_work(&network->work_go_online);
478}
479
480void ipwireless_ppp_close(struct ipw_network *network)
481{
482	/* Disconnect from the wireless network. */
483	if (ipwireless_debug)
484		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": offline\n");
485	schedule_work(&network->work_go_offline);
486}
487
488int ipwireless_ppp_channel_index(struct ipw_network *network)
489{
490	int ret = -1;
491	unsigned long flags;
492
493	spin_lock_irqsave(&network->lock, flags);
494	if (network->ppp_channel != NULL)
495		ret = ppp_channel_index(network->ppp_channel);
496	spin_unlock_irqrestore(&network->lock, flags);
497
498	return ret;
499}
500
501int ipwireless_ppp_unit_number(struct ipw_network *network)
502{
503	int ret = -1;
504	unsigned long flags;
505
506	spin_lock_irqsave(&network->lock, flags);
507	if (network->ppp_channel != NULL)
508		ret = ppp_unit_number(network->ppp_channel);
509	spin_unlock_irqrestore(&network->lock, flags);
510
511	return ret;
512}
513
514int ipwireless_ppp_mru(const struct ipw_network *network)
515{
516	return network->mru;
517}