summaryrefslogtreecommitdiffstats
path: root/drivers/usb/wusbcore/wa-rpipe.c
blob: 6d6da127f6de0578361eac94a11f841254d283cd (plain)
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
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
/*
 * WUSB Wire Adapter
 * rpipe management
 *
 * Copyright (C) 2005-2006 Intel Corporation
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 *
 * FIXME: docs
 *
 * RPIPE
 *
 *   Targeted at different downstream endpoints
 *
 *   Descriptor: use to config the remote pipe.
 *
 *   The number of blocks could be dynamic (wBlocks in descriptor is
 *   0)--need to schedule them then.
 *
 * Each bit in wa->rpipe_bm represents if an rpipe is being used or
 * not. Rpipes are represented with a 'struct wa_rpipe' that is
 * attached to the hcpriv member of a 'struct usb_host_endpoint'.
 *
 * When you need to xfer data to an endpoint, you get an rpipe for it
 * with wa_ep_rpipe_get(), which gives you a reference to the rpipe
 * and keeps a single one (the first one) with the endpoint. When you
 * are done transferring, you drop that reference. At the end the
 * rpipe is always allocated and bound to the endpoint. There it might
 * be recycled when not used.
 *
 * Addresses:
 *
 *  We use a 1:1 mapping mechanism between port address (0 based
 *  index, actually) and the address. The USB stack knows about this.
 *
 *  USB Stack port number    4 (1 based)
 *  WUSB code port index     3 (0 based)
 *  USB Address             5 (2 based -- 0 is for default, 1 for root hub)
 *
 *  Now, because we don't use the concept as default address exactly
 *  like the (wired) USB code does, we need to kind of skip it. So we
 *  never take addresses from the urb->pipe, but from the
 *  urb->dev->devnum, to make sure that we always have the right
 *  destination address.
 */
#include <linux/atomic.h>
#include <linux/bitmap.h>
#include <linux/slab.h>
#include <linux/export.h>

#include "wusbhc.h"
#include "wa-hc.h"

static int __rpipe_get_descr(struct wahc *wa,
			     struct usb_rpipe_descriptor *descr, u16 index)
{
	ssize_t result;
	struct device *dev = &wa->usb_iface->dev;

	/* Get the RPIPE descriptor -- we cannot use the usb_get_descriptor()
	 * function because the arguments are different.
	 */
	result = usb_control_msg(
		wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
		USB_REQ_GET_DESCRIPTOR,
		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_RPIPE,
		USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
		USB_CTRL_GET_TIMEOUT);
	if (result < 0) {
		dev_err(dev, "rpipe %u: get descriptor failed: %d\n",
			index, (int)result);
		goto error;
	}
	if (result < sizeof(*descr)) {
		dev_err(dev, "rpipe %u: got short descriptor "
			"(%zd vs %zd bytes needed)\n",
			index, result, sizeof(*descr));
		result = -EINVAL;
		goto error;
	}
	result = 0;

error:
	return result;
}

/*
 *
 * The descriptor is assumed to be properly initialized (ie: you got
 * it through __rpipe_get_descr()).
 */
static int __rpipe_set_descr(struct wahc *wa,
			     struct usb_rpipe_descriptor *descr, u16 index)
{
	ssize_t result;
	struct device *dev = &wa->usb_iface->dev;

	/* we cannot use the usb_get_descriptor() function because the
	 * arguments are different.
	 */
	result = usb_control_msg(
		wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
		USB_REQ_SET_DESCRIPTOR,
		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
		USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
		USB_CTRL_SET_TIMEOUT);
	if (result < 0) {
		dev_err(dev, "rpipe %u: set descriptor failed: %d\n",
			index, (int)result);
		goto error;
	}
	if (result < sizeof(*descr)) {
		dev_err(dev, "rpipe %u: sent short descriptor "
			"(%zd vs %zd bytes required)\n",
			index, result, sizeof(*descr));
		result = -EINVAL;
		goto error;
	}
	result = 0;

error:
	return result;

}

static void rpipe_init(struct wa_rpipe *rpipe)
{
	kref_init(&rpipe->refcnt);
	spin_lock_init(&rpipe->seg_lock);
	INIT_LIST_HEAD(&rpipe->seg_list);
	INIT_LIST_HEAD(&rpipe->list_node);
}

static unsigned rpipe_get_idx(struct wahc *wa, unsigned rpipe_idx)
{
	unsigned long flags;

	spin_lock_irqsave(&wa->rpipe_lock, flags);
	rpipe_idx = find_next_zero_bit(wa->rpipe_bm, wa->rpipes, rpipe_idx);
	if (rpipe_idx < wa->rpipes)
		set_bit(rpipe_idx, wa->rpipe_bm);
	spin_unlock_irqrestore(&wa->rpipe_lock, flags);

	return rpipe_idx;
}

static void rpipe_put_idx(struct wahc *wa, unsigned rpipe_idx)
{
	unsigned long flags;

	spin_lock_irqsave(&wa->rpipe_lock, flags);
	clear_bit(rpipe_idx, wa->rpipe_bm);
	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
}

void rpipe_destroy(struct kref *_rpipe)
{
	struct wa_rpipe *rpipe = container_of(_rpipe, struct wa_rpipe, refcnt);
	u8 index = le16_to_cpu(rpipe->descr.wRPipeIndex);

	if (rpipe->ep)
		rpipe->ep->hcpriv = NULL;
	rpipe_put_idx(rpipe->wa, index);
	wa_put(rpipe->wa);
	kfree(rpipe);
}
EXPORT_SYMBOL_GPL(rpipe_destroy);

/*
 * Locate an idle rpipe, create an structure for it and return it
 *
 * @wa	  is referenced and unlocked
 * @crs   enum rpipe_attr, required endpoint characteristics
 *
 * The rpipe can be used only sequentially (not in parallel).
 *
 * The rpipe is moved into the "ready" state.
 */
static int rpipe_get_idle(struct wa_rpipe **prpipe, struct wahc *wa, u8 crs,
			  gfp_t gfp)
{
	int result;
	unsigned rpipe_idx;
	struct wa_rpipe *rpipe;
	struct device *dev = &wa->usb_iface->dev;

	rpipe = kzalloc(sizeof(*rpipe), gfp);
	if (rpipe == NULL)
		return -ENOMEM;
	rpipe_init(rpipe);

	/* Look for an idle pipe */
	for (rpipe_idx = 0; rpipe_idx < wa->rpipes; rpipe_idx++) {
		rpipe_idx = rpipe_get_idx(wa, rpipe_idx);
		if (rpipe_idx >= wa->rpipes)	/* no more pipes :( */
			break;
		result =  __rpipe_get_descr(wa, &rpipe->descr, rpipe_idx);
		if (result < 0)
			dev_err(dev, "Can't get descriptor for rpipe %u: %d\n",
				rpipe_idx, result);
		else if ((rpipe->descr.bmCharacteristics & crs) != 0)
			goto found;
		rpipe_put_idx(wa, rpipe_idx);
	}
	*prpipe = NULL;
	kfree(rpipe);
	return -ENXIO;

found:
	set_bit(rpipe_idx, wa->rpipe_bm);
	rpipe->wa = wa_get(wa);
	*prpipe = rpipe;
	return 0;
}

static int __rpipe_reset(struct wahc *wa, unsigned index)
{
	int result;
	struct device *dev = &wa->usb_iface->dev;

	result = usb_control_msg(
		wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
		USB_REQ_RPIPE_RESET,
		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
		0, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
	if (result < 0)
		dev_err(dev, "rpipe %u: reset failed: %d\n",
			index, result);
	return result;
}

/*
 * Fake companion descriptor for ep0
 *
 * See WUSB1.0[7.4.4], most of this is zero for bulk/int/ctl
 */
static struct usb_wireless_ep_comp_descriptor epc0 = {
	.bLength = sizeof(epc0),
	.bDescriptorType = USB_DT_WIRELESS_ENDPOINT_COMP,
	.bMaxBurst = 1,
	.bMaxSequence = 2,
};

/*
 * Look for EP companion descriptor
 *
 * Get there, look for Inara in the endpoint's extra descriptors
 */
static struct usb_wireless_ep_comp_descriptor *rpipe_epc_find(
		struct device *dev, struct usb_host_endpoint *ep)
{
	void *itr;
	size_t itr_size;
	struct usb_descriptor_header *hdr;
	struct usb_wireless_ep_comp_descriptor *epcd;

	if (ep->desc.bEndpointAddress == 0) {
		epcd = &epc0;
		goto out;
	}
	itr = ep->extra;
	itr_size = ep->extralen;
	epcd = NULL;
	while (itr_size > 0) {
		if (itr_size < sizeof(*hdr)) {
			dev_err(dev, "HW Bug? ep 0x%02x: extra descriptors "
				"at offset %zu: only %zu bytes left\n",
				ep->desc.bEndpointAddress,
				itr - (void *) ep->extra, itr_size);
			break;
		}
		hdr = itr;
		if (hdr->bDescriptorType == USB_DT_WIRELESS_ENDPOINT_COMP) {
			epcd = itr;
			break;
		}
		if (hdr->bLength > itr_size) {
			dev_err(dev, "HW Bug? ep 0x%02x: extra descriptor "
				"at offset %zu (type 0x%02x) "
				"length %d but only %zu bytes left\n",
				ep->desc.bEndpointAddress,
				itr - (void *) ep->extra, hdr->bDescriptorType,
				hdr->bLength, itr_size);
			break;
		}
		itr += hdr->bLength;
		itr_size -= hdr->bLength;
	}
out:
	return epcd;
}

/*
 * Aim an rpipe to its device & endpoint destination
 *
 * Make sure we change the address to unauthenticated if the device
 * is WUSB and it is not authenticated.
 */
static int rpipe_aim(struct wa_rpipe *rpipe, struct wahc *wa,
		     struct usb_host_endpoint *ep, struct urb *urb, gfp_t gfp)
{
	int result = -ENOMSG;	/* better code for lack of companion? */
	struct device *dev = &wa->usb_iface->dev;
	struct usb_device *usb_dev = urb->dev;
	struct usb_wireless_ep_comp_descriptor *epcd;
	u32 ack_window, epcd_max_sequence;
	u8 unauth;

	epcd = rpipe_epc_find(dev, ep);
	if (epcd == NULL) {
		dev_err(dev, "ep 0x%02x: can't find companion descriptor\n",
			ep->desc.bEndpointAddress);
		goto error;
	}
	unauth = usb_dev->wusb && !usb_dev->authenticated ? 0x80 : 0;
	__rpipe_reset(wa, le16_to_cpu(rpipe->descr.wRPipeIndex));
	atomic_set(&rpipe->segs_available,
		le16_to_cpu(rpipe->descr.wRequests));
	/* FIXME: block allocation system; request with queuing and timeout */
	/* FIXME: compute so seg_size > ep->maxpktsize */
	rpipe->descr.wBlocks = cpu_to_le16(16);		/* given */
	/* ep0 maxpktsize is 0x200 (WUSB1.0[4.8.1]) */
	if (usb_endpoint_xfer_isoc(&ep->desc))
		rpipe->descr.wMaxPacketSize = epcd->wOverTheAirPacketSize;
	else
		rpipe->descr.wMaxPacketSize = ep->desc.wMaxPacketSize;

	rpipe->descr.hwa_bMaxBurst = max(min_t(unsigned int,
				epcd->bMaxBurst, 16U), 1U);
	rpipe->descr.hwa_bDeviceInfoIndex =
			wusb_port_no_to_idx(urb->dev->portnum);
	/* FIXME: use maximum speed as supported or recommended by device */
	rpipe->descr.bSpeed = usb_pipeendpoint(urb->pipe) == 0 ?
		UWB_PHY_RATE_53 : UWB_PHY_RATE_200;

	dev_dbg(dev, "addr %u (0x%02x) rpipe #%u ep# %u speed %d\n",
		urb->dev->devnum, urb->dev->devnum | unauth,
		le16_to_cpu(rpipe->descr.wRPipeIndex),
		usb_pipeendpoint(urb->pipe), rpipe->descr.bSpeed);

	rpipe->descr.hwa_reserved = 0;

	rpipe->descr.bEndpointAddress = ep->desc.bEndpointAddress;
	/* FIXME: bDataSequence */
	rpipe->descr.bDataSequence = 0;

	/* start with base window of hwa_bMaxBurst bits starting at 0. */
	ack_window = 0xFFFFFFFF >> (32 - rpipe->descr.hwa_bMaxBurst);
	rpipe->descr.dwCurrentWindow = cpu_to_le32(ack_window);
	epcd_max_sequence = max(min_t(unsigned int,
			epcd->bMaxSequence, 32U), 2U);
	rpipe->descr.bMaxDataSequence = epcd_max_sequence - 1;
	rpipe->descr.bInterval = ep->desc.bInterval;
	if (usb_endpoint_xfer_isoc(&ep->desc))
		rpipe->descr.bOverTheAirInterval = epcd->bOverTheAirInterval;
	else
		rpipe->descr.bOverTheAirInterval = 0;	/* 0 if not isoc */
	/* FIXME: xmit power & preamble blah blah */
	rpipe->descr.bmAttribute = (ep->desc.bmAttributes &
					USB_ENDPOINT_XFERTYPE_MASK);
	/* rpipe->descr.bmCharacteristics RO */
	rpipe->descr.bmRetryOptions = (wa->wusb->retry_count & 0xF);
	/* FIXME: use for assessing link quality? */
	rpipe->descr.wNumTransactionErrors = 0;
	result = __rpipe_set_descr(wa, &rpipe->descr,
				   le16_to_cpu(rpipe->descr.wRPipeIndex));
	if (result < 0) {
		dev_err(dev, "Cannot aim rpipe: %d\n", result);
		goto error;
	}
	result = 0;
error:
	return result;
}

/*
 * Check an aimed rpipe to make sure it points to where we want
 *
 * We use bit 19 of the Linux USB pipe bitmap for unauth vs auth
 * space; when it is like that, we or 0x80 to make an unauth address.
 */
static int rpipe_check_aim(const struct wa_rpipe *rpipe, const struct wahc *wa,
			   const struct usb_host_endpoint *ep,
			   const struct urb *urb, gfp_t gfp)
{
	int result = 0;
	struct device *dev = &wa->usb_iface->dev;
	u8 portnum = wusb_port_no_to_idx(urb->dev->portnum);

#define AIM_CHECK(rdf, val, text)					\
	do {								\
		if (rpipe->descr.rdf != (val)) {			\
			dev_err(dev,					\
				"rpipe aim discrepancy: " #rdf " " text "\n", \
				rpipe->descr.rdf, (val));		\
			result = -EINVAL;				\
			WARN_ON(1);					\
		}							\
	} while (0)
	AIM_CHECK(hwa_bDeviceInfoIndex, portnum, "(%u vs %u)");
	AIM_CHECK(bSpeed, usb_pipeendpoint(urb->pipe) == 0 ?
			UWB_PHY_RATE_53 : UWB_PHY_RATE_200,
		  "(%u vs %u)");
	AIM_CHECK(bEndpointAddress, ep->desc.bEndpointAddress, "(%u vs %u)");
	AIM_CHECK(bInterval, ep->desc.bInterval, "(%u vs %u)");
	AIM_CHECK(bmAttribute, ep->desc.bmAttributes & 0x03, "(%u vs %u)");
#undef AIM_CHECK
	return result;
}

#ifndef CONFIG_BUG
#define CONFIG_BUG 0
#endif

/*
 * Make sure there is an rpipe allocated for an endpoint
 *
 * If already allocated, we just refcount it; if not, we get an
 * idle one, aim it to the right location and take it.
 *
 * Attaches to ep->hcpriv and rpipe->ep to ep.
 */
int rpipe_get_by_ep(struct wahc *wa, struct usb_host_endpoint *ep,
		    struct urb *urb, gfp_t gfp)
{
	int result = 0;
	struct device *dev = &wa->usb_iface->dev;
	struct wa_rpipe *rpipe;
	u8 eptype;

	mutex_lock(&wa->rpipe_mutex);
	rpipe = ep->hcpriv;
	if (rpipe != NULL) {
		if (CONFIG_BUG == 1) {
			result = rpipe_check_aim(rpipe, wa, ep, urb, gfp);
			if (result < 0)
				goto error;
		}
		__rpipe_get(rpipe);
		dev_dbg(dev, "ep 0x%02x: reusing rpipe %u\n",
			ep->desc.bEndpointAddress,
			le16_to_cpu(rpipe->descr.wRPipeIndex));
	} else {
		/* hmm, assign idle rpipe, aim it */
		result = -ENOBUFS;
		eptype = ep->desc.bmAttributes & 0x03;
		result = rpipe_get_idle(&rpipe, wa, 1 << eptype, gfp);
		if (result < 0)
			goto error;
		result = rpipe_aim(rpipe, wa, ep, urb, gfp);
		if (result < 0) {
			rpipe_put(rpipe);
			goto error;
		}
		ep->hcpriv = rpipe;
		rpipe->ep = ep;
		__rpipe_get(rpipe);	/* for caching into ep->hcpriv */
		dev_dbg(dev, "ep 0x%02x: using rpipe %u\n",
			ep->desc.bEndpointAddress,
			le16_to_cpu(rpipe->descr.wRPipeIndex));
	}
error:
	mutex_unlock(&wa->rpipe_mutex);
	return result;
}

/*
 * Allocate the bitmap for each rpipe.
 */
int wa_rpipes_create(struct wahc *wa)
{
	wa->rpipes = le16_to_cpu(wa->wa_descr->wNumRPipes);
	wa->rpipe_bm = kzalloc(BITS_TO_LONGS(wa->rpipes)*sizeof(unsigned long),
			       GFP_KERNEL);
	if (wa->rpipe_bm == NULL)
		return -ENOMEM;
	return 0;
}

void wa_rpipes_destroy(struct wahc *wa)
{
	struct device *dev = &wa->usb_iface->dev;

	if (!bitmap_empty(wa->rpipe_bm, wa->rpipes)) {
		char buf[256];
		WARN_ON(1);
		bitmap_scnprintf(buf, sizeof(buf), wa->rpipe_bm, wa->rpipes);
		dev_err(dev, "BUG: pipes not released on exit: %s\n", buf);
	}
	kfree(wa->rpipe_bm);
}

/*
 * Release resources allocated for an endpoint
 *
 * If there is an associated rpipe to this endpoint, Abort any pending
 * transfers and put it. If the rpipe ends up being destroyed,
 * __rpipe_destroy() will cleanup ep->hcpriv.
 *
 * This is called before calling hcd->stop(), so you don't need to do
 * anything else in there.
 */
void rpipe_ep_disable(struct wahc *wa, struct usb_host_endpoint *ep)
{
	struct wa_rpipe *rpipe;

	mutex_lock(&wa->rpipe_mutex);
	rpipe = ep->hcpriv;
	if (rpipe != NULL) {
		u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);

		usb_control_msg(
			wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
			USB_REQ_RPIPE_ABORT,
			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
			0, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
		rpipe_put(rpipe);
	}
	mutex_unlock(&wa->rpipe_mutex);
}
EXPORT_SYMBOL_GPL(rpipe_ep_disable);

/* Clear the stalled status of an RPIPE. */
void rpipe_clear_feature_stalled(struct wahc *wa, struct usb_host_endpoint *ep)
{
	struct wa_rpipe *rpipe;

	mutex_lock(&wa->rpipe_mutex);
	rpipe = ep->hcpriv;
	if (rpipe != NULL) {
		u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);

		usb_control_msg(
			wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
			USB_REQ_CLEAR_FEATURE,
			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
			RPIPE_STALL, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
	}
	mutex_unlock(&wa->rpipe_mutex);
}
EXPORT_SYMBOL_GPL(rpipe_clear_feature_stalled);