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v3.1
 
  1/*
  2 * WUSB Wire Adapter
  3 * rpipe management
  4 *
  5 * Copyright (C) 2005-2006 Intel Corporation
  6 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
  7 *
  8 * This program is free software; you can redistribute it and/or
  9 * modify it under the terms of the GNU General Public License version
 10 * 2 as published by the Free Software Foundation.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, write to the Free Software
 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 20 * 02110-1301, USA.
 21 *
 22 *
 23 * FIXME: docs
 24 *
 25 * RPIPE
 26 *
 27 *   Targeted at different downstream endpoints
 28 *
 29 *   Descriptor: use to config the remote pipe.
 30 *
 31 *   The number of blocks could be dynamic (wBlocks in descriptor is
 32 *   0)--need to schedule them then.
 33 *
 34 * Each bit in wa->rpipe_bm represents if an rpipe is being used or
 35 * not. Rpipes are represented with a 'struct wa_rpipe' that is
 36 * attached to the hcpriv member of a 'struct usb_host_endpoint'.
 37 *
 38 * When you need to xfer data to an endpoint, you get an rpipe for it
 39 * with wa_ep_rpipe_get(), which gives you a reference to the rpipe
 40 * and keeps a single one (the first one) with the endpoint. When you
 41 * are done transferring, you drop that reference. At the end the
 42 * rpipe is always allocated and bound to the endpoint. There it might
 43 * be recycled when not used.
 44 *
 45 * Addresses:
 46 *
 47 *  We use a 1:1 mapping mechanism between port address (0 based
 48 *  index, actually) and the address. The USB stack knows about this.
 49 *
 50 *  USB Stack port number    4 (1 based)
 51 *  WUSB code port index     3 (0 based)
 52 *  USB Address             5 (2 based -- 0 is for default, 1 for root hub)
 53 *
 54 *  Now, because we don't use the concept as default address exactly
 55 *  like the (wired) USB code does, we need to kind of skip it. So we
 56 *  never take addresses from the urb->pipe, but from the
 57 *  urb->dev->devnum, to make sure that we always have the right
 58 *  destination address.
 59 */
 60#include <linux/init.h>
 61#include <linux/atomic.h>
 62#include <linux/bitmap.h>
 63#include <linux/slab.h>
 
 64
 65#include "wusbhc.h"
 66#include "wa-hc.h"
 67
 68static int __rpipe_get_descr(struct wahc *wa,
 69			     struct usb_rpipe_descriptor *descr, u16 index)
 70{
 71	ssize_t result;
 72	struct device *dev = &wa->usb_iface->dev;
 73
 74	/* Get the RPIPE descriptor -- we cannot use the usb_get_descriptor()
 75	 * function because the arguments are different.
 76	 */
 77	result = usb_control_msg(
 78		wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
 79		USB_REQ_GET_DESCRIPTOR,
 80		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_RPIPE,
 81		USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
 82		1000 /* FIXME: arbitrary */);
 83	if (result < 0) {
 84		dev_err(dev, "rpipe %u: get descriptor failed: %d\n",
 85			index, (int)result);
 86		goto error;
 87	}
 88	if (result < sizeof(*descr)) {
 89		dev_err(dev, "rpipe %u: got short descriptor "
 90			"(%zd vs %zd bytes needed)\n",
 91			index, result, sizeof(*descr));
 92		result = -EINVAL;
 93		goto error;
 94	}
 95	result = 0;
 96
 97error:
 98	return result;
 99}
100
101/*
102 *
103 * The descriptor is assumed to be properly initialized (ie: you got
104 * it through __rpipe_get_descr()).
105 */
106static int __rpipe_set_descr(struct wahc *wa,
107			     struct usb_rpipe_descriptor *descr, u16 index)
108{
109	ssize_t result;
110	struct device *dev = &wa->usb_iface->dev;
111
112	/* we cannot use the usb_get_descriptor() function because the
113	 * arguments are different.
114	 */
115	result = usb_control_msg(
116		wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
117		USB_REQ_SET_DESCRIPTOR,
118		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
119		USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
120		HZ / 10);
121	if (result < 0) {
122		dev_err(dev, "rpipe %u: set descriptor failed: %d\n",
123			index, (int)result);
124		goto error;
125	}
126	if (result < sizeof(*descr)) {
127		dev_err(dev, "rpipe %u: sent short descriptor "
128			"(%zd vs %zd bytes required)\n",
129			index, result, sizeof(*descr));
130		result = -EINVAL;
131		goto error;
132	}
133	result = 0;
134
135error:
136	return result;
137
138}
139
140static void rpipe_init(struct wa_rpipe *rpipe)
141{
142	kref_init(&rpipe->refcnt);
143	spin_lock_init(&rpipe->seg_lock);
144	INIT_LIST_HEAD(&rpipe->seg_list);
 
145}
146
147static unsigned rpipe_get_idx(struct wahc *wa, unsigned rpipe_idx)
148{
149	unsigned long flags;
150
151	spin_lock_irqsave(&wa->rpipe_bm_lock, flags);
152	rpipe_idx = find_next_zero_bit(wa->rpipe_bm, wa->rpipes, rpipe_idx);
153	if (rpipe_idx < wa->rpipes)
154		set_bit(rpipe_idx, wa->rpipe_bm);
155	spin_unlock_irqrestore(&wa->rpipe_bm_lock, flags);
156
157	return rpipe_idx;
158}
159
160static void rpipe_put_idx(struct wahc *wa, unsigned rpipe_idx)
161{
162	unsigned long flags;
163
164	spin_lock_irqsave(&wa->rpipe_bm_lock, flags);
165	clear_bit(rpipe_idx, wa->rpipe_bm);
166	spin_unlock_irqrestore(&wa->rpipe_bm_lock, flags);
167}
168
169void rpipe_destroy(struct kref *_rpipe)
170{
171	struct wa_rpipe *rpipe = container_of(_rpipe, struct wa_rpipe, refcnt);
172	u8 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
173
174	if (rpipe->ep)
175		rpipe->ep->hcpriv = NULL;
176	rpipe_put_idx(rpipe->wa, index);
177	wa_put(rpipe->wa);
178	kfree(rpipe);
179}
180EXPORT_SYMBOL_GPL(rpipe_destroy);
181
182/*
183 * Locate an idle rpipe, create an structure for it and return it
184 *
185 * @wa 	  is referenced and unlocked
186 * @crs   enum rpipe_attr, required endpoint characteristics
187 *
188 * The rpipe can be used only sequentially (not in parallel).
189 *
190 * The rpipe is moved into the "ready" state.
191 */
192static int rpipe_get_idle(struct wa_rpipe **prpipe, struct wahc *wa, u8 crs,
193			  gfp_t gfp)
194{
195	int result;
196	unsigned rpipe_idx;
197	struct wa_rpipe *rpipe;
198	struct device *dev = &wa->usb_iface->dev;
199
200	rpipe = kzalloc(sizeof(*rpipe), gfp);
201	if (rpipe == NULL)
202		return -ENOMEM;
203	rpipe_init(rpipe);
204
205	/* Look for an idle pipe */
206	for (rpipe_idx = 0; rpipe_idx < wa->rpipes; rpipe_idx++) {
207		rpipe_idx = rpipe_get_idx(wa, rpipe_idx);
208		if (rpipe_idx >= wa->rpipes)	/* no more pipes :( */
209			break;
210		result =  __rpipe_get_descr(wa, &rpipe->descr, rpipe_idx);
211		if (result < 0)
212			dev_err(dev, "Can't get descriptor for rpipe %u: %d\n",
213				rpipe_idx, result);
214		else if ((rpipe->descr.bmCharacteristics & crs) != 0)
215			goto found;
216		rpipe_put_idx(wa, rpipe_idx);
217	}
218	*prpipe = NULL;
219	kfree(rpipe);
220	return -ENXIO;
221
222found:
223	set_bit(rpipe_idx, wa->rpipe_bm);
224	rpipe->wa = wa_get(wa);
225	*prpipe = rpipe;
226	return 0;
227}
228
229static int __rpipe_reset(struct wahc *wa, unsigned index)
230{
231	int result;
232	struct device *dev = &wa->usb_iface->dev;
233
234	result = usb_control_msg(
235		wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
236		USB_REQ_RPIPE_RESET,
237		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
238		0, index, NULL, 0, 1000 /* FIXME: arbitrary */);
239	if (result < 0)
240		dev_err(dev, "rpipe %u: reset failed: %d\n",
241			index, result);
242	return result;
243}
244
245/*
246 * Fake companion descriptor for ep0
247 *
248 * See WUSB1.0[7.4.4], most of this is zero for bulk/int/ctl
249 */
250static struct usb_wireless_ep_comp_descriptor epc0 = {
251	.bLength = sizeof(epc0),
252	.bDescriptorType = USB_DT_WIRELESS_ENDPOINT_COMP,
253/*	.bMaxBurst = 1, */
254	.bMaxSequence = 31,
255};
256
257/*
258 * Look for EP companion descriptor
259 *
260 * Get there, look for Inara in the endpoint's extra descriptors
261 */
262static struct usb_wireless_ep_comp_descriptor *rpipe_epc_find(
263		struct device *dev, struct usb_host_endpoint *ep)
264{
265	void *itr;
266	size_t itr_size;
267	struct usb_descriptor_header *hdr;
268	struct usb_wireless_ep_comp_descriptor *epcd;
269
270	if (ep->desc.bEndpointAddress == 0) {
271		epcd = &epc0;
272		goto out;
273	}
274	itr = ep->extra;
275	itr_size = ep->extralen;
276	epcd = NULL;
277	while (itr_size > 0) {
278		if (itr_size < sizeof(*hdr)) {
279			dev_err(dev, "HW Bug? ep 0x%02x: extra descriptors "
280				"at offset %zu: only %zu bytes left\n",
281				ep->desc.bEndpointAddress,
282				itr - (void *) ep->extra, itr_size);
283			break;
284		}
285		hdr = itr;
286		if (hdr->bDescriptorType == USB_DT_WIRELESS_ENDPOINT_COMP) {
287			epcd = itr;
288			break;
289		}
290		if (hdr->bLength > itr_size) {
291			dev_err(dev, "HW Bug? ep 0x%02x: extra descriptor "
292				"at offset %zu (type 0x%02x) "
293				"length %d but only %zu bytes left\n",
294				ep->desc.bEndpointAddress,
295				itr - (void *) ep->extra, hdr->bDescriptorType,
296				hdr->bLength, itr_size);
297			break;
298		}
299		itr += hdr->bLength;
300		itr_size -= hdr->bDescriptorType;
301	}
302out:
303	return epcd;
304}
305
306/*
307 * Aim an rpipe to its device & endpoint destination
308 *
309 * Make sure we change the address to unauthenticathed if the device
310 * is WUSB and it is not authenticated.
311 */
312static int rpipe_aim(struct wa_rpipe *rpipe, struct wahc *wa,
313		     struct usb_host_endpoint *ep, struct urb *urb, gfp_t gfp)
314{
315	int result = -ENOMSG;	/* better code for lack of companion? */
316	struct device *dev = &wa->usb_iface->dev;
317	struct usb_device *usb_dev = urb->dev;
318	struct usb_wireless_ep_comp_descriptor *epcd;
 
319	u8 unauth;
320
321	epcd = rpipe_epc_find(dev, ep);
322	if (epcd == NULL) {
323		dev_err(dev, "ep 0x%02x: can't find companion descriptor\n",
324			ep->desc.bEndpointAddress);
325		goto error;
326	}
327	unauth = usb_dev->wusb && !usb_dev->authenticated ? 0x80 : 0;
328	__rpipe_reset(wa, le16_to_cpu(rpipe->descr.wRPipeIndex));
329	atomic_set(&rpipe->segs_available, le16_to_cpu(rpipe->descr.wRequests));
 
330	/* FIXME: block allocation system; request with queuing and timeout */
331	/* FIXME: compute so seg_size > ep->maxpktsize */
332	rpipe->descr.wBlocks = cpu_to_le16(16);		/* given */
333	/* ep0 maxpktsize is 0x200 (WUSB1.0[4.8.1]) */
334	rpipe->descr.wMaxPacketSize = cpu_to_le16(ep->desc.wMaxPacketSize);
335	rpipe->descr.bHSHubAddress = 0;			/* reserved: zero */
336	rpipe->descr.bHSHubPort = wusb_port_no_to_idx(urb->dev->portnum);
 
 
 
 
 
 
337	/* FIXME: use maximum speed as supported or recommended by device */
338	rpipe->descr.bSpeed = usb_pipeendpoint(urb->pipe) == 0 ?
339		UWB_PHY_RATE_53 : UWB_PHY_RATE_200;
340
341	dev_dbg(dev, "addr %u (0x%02x) rpipe #%u ep# %u speed %d\n",
342		urb->dev->devnum, urb->dev->devnum | unauth,
343		le16_to_cpu(rpipe->descr.wRPipeIndex),
344		usb_pipeendpoint(urb->pipe), rpipe->descr.bSpeed);
345
346	/* see security.c:wusb_update_address() */
347	if (unlikely(urb->dev->devnum == 0x80))
348		rpipe->descr.bDeviceAddress = 0;
349	else
350		rpipe->descr.bDeviceAddress = urb->dev->devnum | unauth;
351	rpipe->descr.bEndpointAddress = ep->desc.bEndpointAddress;
352	/* FIXME: bDataSequence */
353	rpipe->descr.bDataSequence = 0;
354	/* FIXME: dwCurrentWindow */
355	rpipe->descr.dwCurrentWindow = cpu_to_le32(1);
356	/* FIXME: bMaxDataSequence */
357	rpipe->descr.bMaxDataSequence = epcd->bMaxSequence - 1;
 
 
 
358	rpipe->descr.bInterval = ep->desc.bInterval;
359	/* FIXME: bOverTheAirInterval */
360	rpipe->descr.bOverTheAirInterval = 0;	/* 0 if not isoc */
 
 
361	/* FIXME: xmit power & preamble blah blah */
362	rpipe->descr.bmAttribute = ep->desc.bmAttributes & 0x03;
 
363	/* rpipe->descr.bmCharacteristics RO */
364	/* FIXME: bmRetryOptions */
365	rpipe->descr.bmRetryOptions = 15;
366	/* FIXME: use for assessing link quality? */
367	rpipe->descr.wNumTransactionErrors = 0;
368	result = __rpipe_set_descr(wa, &rpipe->descr,
369				   le16_to_cpu(rpipe->descr.wRPipeIndex));
370	if (result < 0) {
371		dev_err(dev, "Cannot aim rpipe: %d\n", result);
372		goto error;
373	}
374	result = 0;
375error:
376	return result;
377}
378
379/*
380 * Check an aimed rpipe to make sure it points to where we want
381 *
382 * We use bit 19 of the Linux USB pipe bitmap for unauth vs auth
383 * space; when it is like that, we or 0x80 to make an unauth address.
384 */
385static int rpipe_check_aim(const struct wa_rpipe *rpipe, const struct wahc *wa,
386			   const struct usb_host_endpoint *ep,
387			   const struct urb *urb, gfp_t gfp)
388{
389	int result = 0;		/* better code for lack of companion? */
390	struct device *dev = &wa->usb_iface->dev;
391	struct usb_device *usb_dev = urb->dev;
392	u8 unauth = (usb_dev->wusb && !usb_dev->authenticated) ? 0x80 : 0;
393	u8 portnum = wusb_port_no_to_idx(urb->dev->portnum);
394
395#define AIM_CHECK(rdf, val, text)					\
396	do {								\
397		if (rpipe->descr.rdf != (val)) {			\
398			dev_err(dev,					\
399				"rpipe aim discrepancy: " #rdf " " text "\n", \
400				rpipe->descr.rdf, (val));		\
401			result = -EINVAL;				\
402			WARN_ON(1);					\
403		}							\
404	} while (0)
405	AIM_CHECK(wMaxPacketSize, cpu_to_le16(ep->desc.wMaxPacketSize),
406		  "(%u vs %u)");
407	AIM_CHECK(bHSHubPort, portnum, "(%u vs %u)");
408	AIM_CHECK(bSpeed, usb_pipeendpoint(urb->pipe) == 0 ?
409			UWB_PHY_RATE_53 : UWB_PHY_RATE_200,
410		  "(%u vs %u)");
411	AIM_CHECK(bDeviceAddress, urb->dev->devnum | unauth, "(%u vs %u)");
412	AIM_CHECK(bEndpointAddress, ep->desc.bEndpointAddress, "(%u vs %u)");
413	AIM_CHECK(bInterval, ep->desc.bInterval, "(%u vs %u)");
414	AIM_CHECK(bmAttribute, ep->desc.bmAttributes & 0x03, "(%u vs %u)");
415#undef AIM_CHECK
416	return result;
417}
418
419#ifndef CONFIG_BUG
420#define CONFIG_BUG 0
421#endif
422
423/*
424 * Make sure there is an rpipe allocated for an endpoint
425 *
426 * If already allocated, we just refcount it; if not, we get an
427 * idle one, aim it to the right location and take it.
428 *
429 * Attaches to ep->hcpriv and rpipe->ep to ep.
430 */
431int rpipe_get_by_ep(struct wahc *wa, struct usb_host_endpoint *ep,
432		    struct urb *urb, gfp_t gfp)
433{
434	int result = 0;
435	struct device *dev = &wa->usb_iface->dev;
436	struct wa_rpipe *rpipe;
437	u8 eptype;
438
439	mutex_lock(&wa->rpipe_mutex);
440	rpipe = ep->hcpriv;
441	if (rpipe != NULL) {
442		if (CONFIG_BUG == 1) {
443			result = rpipe_check_aim(rpipe, wa, ep, urb, gfp);
444			if (result < 0)
445				goto error;
446		}
447		__rpipe_get(rpipe);
448		dev_dbg(dev, "ep 0x%02x: reusing rpipe %u\n",
449			ep->desc.bEndpointAddress,
450			le16_to_cpu(rpipe->descr.wRPipeIndex));
451	} else {
452		/* hmm, assign idle rpipe, aim it */
453		result = -ENOBUFS;
454		eptype = ep->desc.bmAttributes & 0x03;
455		result = rpipe_get_idle(&rpipe, wa, 1 << eptype, gfp);
456		if (result < 0)
457			goto error;
458		result = rpipe_aim(rpipe, wa, ep, urb, gfp);
459		if (result < 0) {
460			rpipe_put(rpipe);
461			goto error;
462		}
463		ep->hcpriv = rpipe;
464		rpipe->ep = ep;
465		__rpipe_get(rpipe);	/* for caching into ep->hcpriv */
466		dev_dbg(dev, "ep 0x%02x: using rpipe %u\n",
467			ep->desc.bEndpointAddress,
468			le16_to_cpu(rpipe->descr.wRPipeIndex));
469	}
470error:
471	mutex_unlock(&wa->rpipe_mutex);
472	return result;
473}
474
475/*
476 * Allocate the bitmap for each rpipe.
477 */
478int wa_rpipes_create(struct wahc *wa)
479{
480	wa->rpipes = wa->wa_descr->wNumRPipes;
481	wa->rpipe_bm = kzalloc(BITS_TO_LONGS(wa->rpipes)*sizeof(unsigned long),
482			       GFP_KERNEL);
483	if (wa->rpipe_bm == NULL)
484		return -ENOMEM;
485	return 0;
486}
487
488void wa_rpipes_destroy(struct wahc *wa)
489{
490	struct device *dev = &wa->usb_iface->dev;
491
492	if (!bitmap_empty(wa->rpipe_bm, wa->rpipes)) {
493		char buf[256];
494		WARN_ON(1);
495		bitmap_scnprintf(buf, sizeof(buf), wa->rpipe_bm, wa->rpipes);
496		dev_err(dev, "BUG: pipes not released on exit: %s\n", buf);
497	}
498	kfree(wa->rpipe_bm);
499}
500
501/*
502 * Release resources allocated for an endpoint
503 *
504 * If there is an associated rpipe to this endpoint, Abort any pending
505 * transfers and put it. If the rpipe ends up being destroyed,
506 * __rpipe_destroy() will cleanup ep->hcpriv.
507 *
508 * This is called before calling hcd->stop(), so you don't need to do
509 * anything else in there.
510 */
511void rpipe_ep_disable(struct wahc *wa, struct usb_host_endpoint *ep)
512{
513	struct wa_rpipe *rpipe;
514
515	mutex_lock(&wa->rpipe_mutex);
516	rpipe = ep->hcpriv;
517	if (rpipe != NULL) {
518		u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
519
520		usb_control_msg(
521			wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
522			USB_REQ_RPIPE_ABORT,
523			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
524			0, index, NULL, 0, 1000 /* FIXME: arbitrary */);
525		rpipe_put(rpipe);
526	}
527	mutex_unlock(&wa->rpipe_mutex);
528}
529EXPORT_SYMBOL_GPL(rpipe_ep_disable);
v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * WUSB Wire Adapter
  4 * rpipe management
  5 *
  6 * Copyright (C) 2005-2006 Intel Corporation
  7 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
  8 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9 * FIXME: docs
 10 *
 11 * RPIPE
 12 *
 13 *   Targeted at different downstream endpoints
 14 *
 15 *   Descriptor: use to config the remote pipe.
 16 *
 17 *   The number of blocks could be dynamic (wBlocks in descriptor is
 18 *   0)--need to schedule them then.
 19 *
 20 * Each bit in wa->rpipe_bm represents if an rpipe is being used or
 21 * not. Rpipes are represented with a 'struct wa_rpipe' that is
 22 * attached to the hcpriv member of a 'struct usb_host_endpoint'.
 23 *
 24 * When you need to xfer data to an endpoint, you get an rpipe for it
 25 * with wa_ep_rpipe_get(), which gives you a reference to the rpipe
 26 * and keeps a single one (the first one) with the endpoint. When you
 27 * are done transferring, you drop that reference. At the end the
 28 * rpipe is always allocated and bound to the endpoint. There it might
 29 * be recycled when not used.
 30 *
 31 * Addresses:
 32 *
 33 *  We use a 1:1 mapping mechanism between port address (0 based
 34 *  index, actually) and the address. The USB stack knows about this.
 35 *
 36 *  USB Stack port number    4 (1 based)
 37 *  WUSB code port index     3 (0 based)
 38 *  USB Address             5 (2 based -- 0 is for default, 1 for root hub)
 39 *
 40 *  Now, because we don't use the concept as default address exactly
 41 *  like the (wired) USB code does, we need to kind of skip it. So we
 42 *  never take addresses from the urb->pipe, but from the
 43 *  urb->dev->devnum, to make sure that we always have the right
 44 *  destination address.
 45 */
 
 46#include <linux/atomic.h>
 47#include <linux/bitmap.h>
 48#include <linux/slab.h>
 49#include <linux/export.h>
 50
 51#include "wusbhc.h"
 52#include "wa-hc.h"
 53
 54static int __rpipe_get_descr(struct wahc *wa,
 55			     struct usb_rpipe_descriptor *descr, u16 index)
 56{
 57	ssize_t result;
 58	struct device *dev = &wa->usb_iface->dev;
 59
 60	/* Get the RPIPE descriptor -- we cannot use the usb_get_descriptor()
 61	 * function because the arguments are different.
 62	 */
 63	result = usb_control_msg(
 64		wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
 65		USB_REQ_GET_DESCRIPTOR,
 66		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_RPIPE,
 67		USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
 68		USB_CTRL_GET_TIMEOUT);
 69	if (result < 0) {
 70		dev_err(dev, "rpipe %u: get descriptor failed: %d\n",
 71			index, (int)result);
 72		goto error;
 73	}
 74	if (result < sizeof(*descr)) {
 75		dev_err(dev, "rpipe %u: got short descriptor "
 76			"(%zd vs %zd bytes needed)\n",
 77			index, result, sizeof(*descr));
 78		result = -EINVAL;
 79		goto error;
 80	}
 81	result = 0;
 82
 83error:
 84	return result;
 85}
 86
 87/*
 88 *
 89 * The descriptor is assumed to be properly initialized (ie: you got
 90 * it through __rpipe_get_descr()).
 91 */
 92static int __rpipe_set_descr(struct wahc *wa,
 93			     struct usb_rpipe_descriptor *descr, u16 index)
 94{
 95	ssize_t result;
 96	struct device *dev = &wa->usb_iface->dev;
 97
 98	/* we cannot use the usb_get_descriptor() function because the
 99	 * arguments are different.
100	 */
101	result = usb_control_msg(
102		wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
103		USB_REQ_SET_DESCRIPTOR,
104		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
105		USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
106		USB_CTRL_SET_TIMEOUT);
107	if (result < 0) {
108		dev_err(dev, "rpipe %u: set descriptor failed: %d\n",
109			index, (int)result);
110		goto error;
111	}
112	if (result < sizeof(*descr)) {
113		dev_err(dev, "rpipe %u: sent short descriptor "
114			"(%zd vs %zd bytes required)\n",
115			index, result, sizeof(*descr));
116		result = -EINVAL;
117		goto error;
118	}
119	result = 0;
120
121error:
122	return result;
123
124}
125
126static void rpipe_init(struct wa_rpipe *rpipe)
127{
128	kref_init(&rpipe->refcnt);
129	spin_lock_init(&rpipe->seg_lock);
130	INIT_LIST_HEAD(&rpipe->seg_list);
131	INIT_LIST_HEAD(&rpipe->list_node);
132}
133
134static unsigned rpipe_get_idx(struct wahc *wa, unsigned rpipe_idx)
135{
136	unsigned long flags;
137
138	spin_lock_irqsave(&wa->rpipe_lock, flags);
139	rpipe_idx = find_next_zero_bit(wa->rpipe_bm, wa->rpipes, rpipe_idx);
140	if (rpipe_idx < wa->rpipes)
141		set_bit(rpipe_idx, wa->rpipe_bm);
142	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
143
144	return rpipe_idx;
145}
146
147static void rpipe_put_idx(struct wahc *wa, unsigned rpipe_idx)
148{
149	unsigned long flags;
150
151	spin_lock_irqsave(&wa->rpipe_lock, flags);
152	clear_bit(rpipe_idx, wa->rpipe_bm);
153	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
154}
155
156void rpipe_destroy(struct kref *_rpipe)
157{
158	struct wa_rpipe *rpipe = container_of(_rpipe, struct wa_rpipe, refcnt);
159	u8 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
160
161	if (rpipe->ep)
162		rpipe->ep->hcpriv = NULL;
163	rpipe_put_idx(rpipe->wa, index);
164	wa_put(rpipe->wa);
165	kfree(rpipe);
166}
167EXPORT_SYMBOL_GPL(rpipe_destroy);
168
169/*
170 * Locate an idle rpipe, create an structure for it and return it
171 *
172 * @wa	  is referenced and unlocked
173 * @crs   enum rpipe_attr, required endpoint characteristics
174 *
175 * The rpipe can be used only sequentially (not in parallel).
176 *
177 * The rpipe is moved into the "ready" state.
178 */
179static int rpipe_get_idle(struct wa_rpipe **prpipe, struct wahc *wa, u8 crs,
180			  gfp_t gfp)
181{
182	int result;
183	unsigned rpipe_idx;
184	struct wa_rpipe *rpipe;
185	struct device *dev = &wa->usb_iface->dev;
186
187	rpipe = kzalloc(sizeof(*rpipe), gfp);
188	if (rpipe == NULL)
189		return -ENOMEM;
190	rpipe_init(rpipe);
191
192	/* Look for an idle pipe */
193	for (rpipe_idx = 0; rpipe_idx < wa->rpipes; rpipe_idx++) {
194		rpipe_idx = rpipe_get_idx(wa, rpipe_idx);
195		if (rpipe_idx >= wa->rpipes)	/* no more pipes :( */
196			break;
197		result =  __rpipe_get_descr(wa, &rpipe->descr, rpipe_idx);
198		if (result < 0)
199			dev_err(dev, "Can't get descriptor for rpipe %u: %d\n",
200				rpipe_idx, result);
201		else if ((rpipe->descr.bmCharacteristics & crs) != 0)
202			goto found;
203		rpipe_put_idx(wa, rpipe_idx);
204	}
205	*prpipe = NULL;
206	kfree(rpipe);
207	return -ENXIO;
208
209found:
210	set_bit(rpipe_idx, wa->rpipe_bm);
211	rpipe->wa = wa_get(wa);
212	*prpipe = rpipe;
213	return 0;
214}
215
216static int __rpipe_reset(struct wahc *wa, unsigned index)
217{
218	int result;
219	struct device *dev = &wa->usb_iface->dev;
220
221	result = usb_control_msg(
222		wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
223		USB_REQ_RPIPE_RESET,
224		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
225		0, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
226	if (result < 0)
227		dev_err(dev, "rpipe %u: reset failed: %d\n",
228			index, result);
229	return result;
230}
231
232/*
233 * Fake companion descriptor for ep0
234 *
235 * See WUSB1.0[7.4.4], most of this is zero for bulk/int/ctl
236 */
237static struct usb_wireless_ep_comp_descriptor epc0 = {
238	.bLength = sizeof(epc0),
239	.bDescriptorType = USB_DT_WIRELESS_ENDPOINT_COMP,
240	.bMaxBurst = 1,
241	.bMaxSequence = 2,
242};
243
244/*
245 * Look for EP companion descriptor
246 *
247 * Get there, look for Inara in the endpoint's extra descriptors
248 */
249static struct usb_wireless_ep_comp_descriptor *rpipe_epc_find(
250		struct device *dev, struct usb_host_endpoint *ep)
251{
252	void *itr;
253	size_t itr_size;
254	struct usb_descriptor_header *hdr;
255	struct usb_wireless_ep_comp_descriptor *epcd;
256
257	if (ep->desc.bEndpointAddress == 0) {
258		epcd = &epc0;
259		goto out;
260	}
261	itr = ep->extra;
262	itr_size = ep->extralen;
263	epcd = NULL;
264	while (itr_size > 0) {
265		if (itr_size < sizeof(*hdr)) {
266			dev_err(dev, "HW Bug? ep 0x%02x: extra descriptors "
267				"at offset %zu: only %zu bytes left\n",
268				ep->desc.bEndpointAddress,
269				itr - (void *) ep->extra, itr_size);
270			break;
271		}
272		hdr = itr;
273		if (hdr->bDescriptorType == USB_DT_WIRELESS_ENDPOINT_COMP) {
274			epcd = itr;
275			break;
276		}
277		if (hdr->bLength > itr_size) {
278			dev_err(dev, "HW Bug? ep 0x%02x: extra descriptor "
279				"at offset %zu (type 0x%02x) "
280				"length %d but only %zu bytes left\n",
281				ep->desc.bEndpointAddress,
282				itr - (void *) ep->extra, hdr->bDescriptorType,
283				hdr->bLength, itr_size);
284			break;
285		}
286		itr += hdr->bLength;
287		itr_size -= hdr->bLength;
288	}
289out:
290	return epcd;
291}
292
293/*
294 * Aim an rpipe to its device & endpoint destination
295 *
296 * Make sure we change the address to unauthenticated if the device
297 * is WUSB and it is not authenticated.
298 */
299static int rpipe_aim(struct wa_rpipe *rpipe, struct wahc *wa,
300		     struct usb_host_endpoint *ep, struct urb *urb, gfp_t gfp)
301{
302	int result = -ENOMSG;	/* better code for lack of companion? */
303	struct device *dev = &wa->usb_iface->dev;
304	struct usb_device *usb_dev = urb->dev;
305	struct usb_wireless_ep_comp_descriptor *epcd;
306	u32 ack_window, epcd_max_sequence;
307	u8 unauth;
308
309	epcd = rpipe_epc_find(dev, ep);
310	if (epcd == NULL) {
311		dev_err(dev, "ep 0x%02x: can't find companion descriptor\n",
312			ep->desc.bEndpointAddress);
313		goto error;
314	}
315	unauth = usb_dev->wusb && !usb_dev->authenticated ? 0x80 : 0;
316	__rpipe_reset(wa, le16_to_cpu(rpipe->descr.wRPipeIndex));
317	atomic_set(&rpipe->segs_available,
318		le16_to_cpu(rpipe->descr.wRequests));
319	/* FIXME: block allocation system; request with queuing and timeout */
320	/* FIXME: compute so seg_size > ep->maxpktsize */
321	rpipe->descr.wBlocks = cpu_to_le16(16);		/* given */
322	/* ep0 maxpktsize is 0x200 (WUSB1.0[4.8.1]) */
323	if (usb_endpoint_xfer_isoc(&ep->desc))
324		rpipe->descr.wMaxPacketSize = epcd->wOverTheAirPacketSize;
325	else
326		rpipe->descr.wMaxPacketSize = ep->desc.wMaxPacketSize;
327
328	rpipe->descr.hwa_bMaxBurst = max(min_t(unsigned int,
329				epcd->bMaxBurst, 16U), 1U);
330	rpipe->descr.hwa_bDeviceInfoIndex =
331			wusb_port_no_to_idx(urb->dev->portnum);
332	/* FIXME: use maximum speed as supported or recommended by device */
333	rpipe->descr.bSpeed = usb_pipeendpoint(urb->pipe) == 0 ?
334		UWB_PHY_RATE_53 : UWB_PHY_RATE_200;
335
336	dev_dbg(dev, "addr %u (0x%02x) rpipe #%u ep# %u speed %d\n",
337		urb->dev->devnum, urb->dev->devnum | unauth,
338		le16_to_cpu(rpipe->descr.wRPipeIndex),
339		usb_pipeendpoint(urb->pipe), rpipe->descr.bSpeed);
340
341	rpipe->descr.hwa_reserved = 0;
342
 
 
 
343	rpipe->descr.bEndpointAddress = ep->desc.bEndpointAddress;
344	/* FIXME: bDataSequence */
345	rpipe->descr.bDataSequence = 0;
346
347	/* start with base window of hwa_bMaxBurst bits starting at 0. */
348	ack_window = 0xFFFFFFFF >> (32 - rpipe->descr.hwa_bMaxBurst);
349	rpipe->descr.dwCurrentWindow = cpu_to_le32(ack_window);
350	epcd_max_sequence = max(min_t(unsigned int,
351			epcd->bMaxSequence, 32U), 2U);
352	rpipe->descr.bMaxDataSequence = epcd_max_sequence - 1;
353	rpipe->descr.bInterval = ep->desc.bInterval;
354	if (usb_endpoint_xfer_isoc(&ep->desc))
355		rpipe->descr.bOverTheAirInterval = epcd->bOverTheAirInterval;
356	else
357		rpipe->descr.bOverTheAirInterval = 0;	/* 0 if not isoc */
358	/* FIXME: xmit power & preamble blah blah */
359	rpipe->descr.bmAttribute = (ep->desc.bmAttributes &
360					USB_ENDPOINT_XFERTYPE_MASK);
361	/* rpipe->descr.bmCharacteristics RO */
362	rpipe->descr.bmRetryOptions = (wa->wusb->retry_count & 0xF);
 
363	/* FIXME: use for assessing link quality? */
364	rpipe->descr.wNumTransactionErrors = 0;
365	result = __rpipe_set_descr(wa, &rpipe->descr,
366				   le16_to_cpu(rpipe->descr.wRPipeIndex));
367	if (result < 0) {
368		dev_err(dev, "Cannot aim rpipe: %d\n", result);
369		goto error;
370	}
371	result = 0;
372error:
373	return result;
374}
375
376/*
377 * Check an aimed rpipe to make sure it points to where we want
378 *
379 * We use bit 19 of the Linux USB pipe bitmap for unauth vs auth
380 * space; when it is like that, we or 0x80 to make an unauth address.
381 */
382static int rpipe_check_aim(const struct wa_rpipe *rpipe, const struct wahc *wa,
383			   const struct usb_host_endpoint *ep,
384			   const struct urb *urb, gfp_t gfp)
385{
386	int result = 0;
387	struct device *dev = &wa->usb_iface->dev;
 
 
388	u8 portnum = wusb_port_no_to_idx(urb->dev->portnum);
389
390#define AIM_CHECK(rdf, val, text)					\
391	do {								\
392		if (rpipe->descr.rdf != (val)) {			\
393			dev_err(dev,					\
394				"rpipe aim discrepancy: " #rdf " " text "\n", \
395				rpipe->descr.rdf, (val));		\
396			result = -EINVAL;				\
397			WARN_ON(1);					\
398		}							\
399	} while (0)
400	AIM_CHECK(hwa_bDeviceInfoIndex, portnum, "(%u vs %u)");
 
 
401	AIM_CHECK(bSpeed, usb_pipeendpoint(urb->pipe) == 0 ?
402			UWB_PHY_RATE_53 : UWB_PHY_RATE_200,
403		  "(%u vs %u)");
 
404	AIM_CHECK(bEndpointAddress, ep->desc.bEndpointAddress, "(%u vs %u)");
405	AIM_CHECK(bInterval, ep->desc.bInterval, "(%u vs %u)");
406	AIM_CHECK(bmAttribute, ep->desc.bmAttributes & 0x03, "(%u vs %u)");
407#undef AIM_CHECK
408	return result;
409}
410
411#ifndef CONFIG_BUG
412#define CONFIG_BUG 0
413#endif
414
415/*
416 * Make sure there is an rpipe allocated for an endpoint
417 *
418 * If already allocated, we just refcount it; if not, we get an
419 * idle one, aim it to the right location and take it.
420 *
421 * Attaches to ep->hcpriv and rpipe->ep to ep.
422 */
423int rpipe_get_by_ep(struct wahc *wa, struct usb_host_endpoint *ep,
424		    struct urb *urb, gfp_t gfp)
425{
426	int result = 0;
427	struct device *dev = &wa->usb_iface->dev;
428	struct wa_rpipe *rpipe;
429	u8 eptype;
430
431	mutex_lock(&wa->rpipe_mutex);
432	rpipe = ep->hcpriv;
433	if (rpipe != NULL) {
434		if (CONFIG_BUG == 1) {
435			result = rpipe_check_aim(rpipe, wa, ep, urb, gfp);
436			if (result < 0)
437				goto error;
438		}
439		__rpipe_get(rpipe);
440		dev_dbg(dev, "ep 0x%02x: reusing rpipe %u\n",
441			ep->desc.bEndpointAddress,
442			le16_to_cpu(rpipe->descr.wRPipeIndex));
443	} else {
444		/* hmm, assign idle rpipe, aim it */
445		result = -ENOBUFS;
446		eptype = ep->desc.bmAttributes & 0x03;
447		result = rpipe_get_idle(&rpipe, wa, 1 << eptype, gfp);
448		if (result < 0)
449			goto error;
450		result = rpipe_aim(rpipe, wa, ep, urb, gfp);
451		if (result < 0) {
452			rpipe_put(rpipe);
453			goto error;
454		}
455		ep->hcpriv = rpipe;
456		rpipe->ep = ep;
457		__rpipe_get(rpipe);	/* for caching into ep->hcpriv */
458		dev_dbg(dev, "ep 0x%02x: using rpipe %u\n",
459			ep->desc.bEndpointAddress,
460			le16_to_cpu(rpipe->descr.wRPipeIndex));
461	}
462error:
463	mutex_unlock(&wa->rpipe_mutex);
464	return result;
465}
466
467/*
468 * Allocate the bitmap for each rpipe.
469 */
470int wa_rpipes_create(struct wahc *wa)
471{
472	wa->rpipes = le16_to_cpu(wa->wa_descr->wNumRPipes);
473	wa->rpipe_bm = kzalloc(BITS_TO_LONGS(wa->rpipes)*sizeof(unsigned long),
474			       GFP_KERNEL);
475	if (wa->rpipe_bm == NULL)
476		return -ENOMEM;
477	return 0;
478}
479
480void wa_rpipes_destroy(struct wahc *wa)
481{
482	struct device *dev = &wa->usb_iface->dev;
483
484	if (!bitmap_empty(wa->rpipe_bm, wa->rpipes)) {
 
485		WARN_ON(1);
486		dev_err(dev, "BUG: pipes not released on exit: %*pb\n",
487			wa->rpipes, wa->rpipe_bm);
488	}
489	kfree(wa->rpipe_bm);
490}
491
492/*
493 * Release resources allocated for an endpoint
494 *
495 * If there is an associated rpipe to this endpoint, Abort any pending
496 * transfers and put it. If the rpipe ends up being destroyed,
497 * __rpipe_destroy() will cleanup ep->hcpriv.
498 *
499 * This is called before calling hcd->stop(), so you don't need to do
500 * anything else in there.
501 */
502void rpipe_ep_disable(struct wahc *wa, struct usb_host_endpoint *ep)
503{
504	struct wa_rpipe *rpipe;
505
506	mutex_lock(&wa->rpipe_mutex);
507	rpipe = ep->hcpriv;
508	if (rpipe != NULL) {
509		u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
510
511		usb_control_msg(
512			wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
513			USB_REQ_RPIPE_ABORT,
514			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
515			0, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
516		rpipe_put(rpipe);
517	}
518	mutex_unlock(&wa->rpipe_mutex);
519}
520EXPORT_SYMBOL_GPL(rpipe_ep_disable);
521
522/* Clear the stalled status of an RPIPE. */
523void rpipe_clear_feature_stalled(struct wahc *wa, struct usb_host_endpoint *ep)
524{
525	struct wa_rpipe *rpipe;
526
527	mutex_lock(&wa->rpipe_mutex);
528	rpipe = ep->hcpriv;
529	if (rpipe != NULL) {
530		u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
531
532		usb_control_msg(
533			wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
534			USB_REQ_CLEAR_FEATURE,
535			USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
536			RPIPE_STALL, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
537	}
538	mutex_unlock(&wa->rpipe_mutex);
539}
540EXPORT_SYMBOL_GPL(rpipe_clear_feature_stalled);