drivers/usb/wusbcore/wa-rpipe.c

   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  *   Targetted 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 Addresss             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 <asm/atomic.h>
  62 #include <linux/bitmap.h>
  63 #include <linux/slab.h>
  64
  65 #include "wusbhc.h"
  66 #include "wa-hc.h"
  67
  68 static 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
  97 error:
  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  */
 106 static 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
 135 error:
 136         return result;
 137
 138 }
 139
 140 static 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
 147 static 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
 160 static 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
 169 void 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 }
 180 EXPORT_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  */
 192 static 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
 222 found:
 223         set_bit(rpipe_idx, wa->rpipe_bm);
 224         rpipe->wa = wa_get(wa);
 225         *prpipe = rpipe;
 226         return 0;
 227 }
 228
 229 static 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  */
 250 static 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  */
 262 static 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         }
 302 out:
 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  */
 312 static 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;
 375 error:
 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  */
 385 static 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  */
 431 int 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         }
 470 error:
 471         mutex_unlock(&wa->rpipe_mutex);
 472         return result;
 473 }
 474
 475 /*
 476  * Allocate the bitmap for each rpipe.
 477  */
 478 int 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
 488 void 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  */
 511 void 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 }
 529 EXPORT_SYMBOL_GPL(rpipe_ep_disable);