drivers/staging/greybus/es2.c

   1 /*
   2  * Greybus "AP" USB driver for "ES2" controller chips
   3  *
   4  * Copyright 2014-2015 Google Inc.
   5  * Copyright 2014-2015 Linaro Ltd.
   6  *
   7  * Released under the GPLv2 only.
   8  */
   9 #include <linux/kthread.h>
  10 #include <linux/sizes.h>
  11 #include <linux/usb.h>
  12 #include <linux/kfifo.h>
  13 #include <linux/debugfs.h>
  14 #include <asm/unaligned.h>
  15
  16 #include "greybus.h"
  17 #include "kernel_ver.h"
  18 #include "connection.h"
  19 #include "greybus_trace.h"
  20
  21
  22 /* Fixed CPort numbers */
  23 #define ES2_CPORT_CDSI0         16
  24 #define ES2_CPORT_CDSI1         17
  25
  26 /* Memory sizes for the buffers sent to/from the ES2 controller */
  27 #define ES2_GBUF_MSG_SIZE_MAX   2048
  28
  29 static const struct usb_device_id id_table[] = {
  30         { USB_DEVICE(0x18d1, 0x1eaf) },
  31         { },
  32 };
  33 MODULE_DEVICE_TABLE(usb, id_table);
  34
  35 #define APB1_LOG_SIZE           SZ_16K
  36
  37 /* Number of bulk in and bulk out couple */
  38 #define NUM_BULKS               7
  39
  40 /*
  41  * Number of CPort IN urbs in flight at any point in time.
  42  * Adjust if we are having stalls in the USB buffer due to not enough urbs in
  43  * flight.
  44  */
  45 #define NUM_CPORT_IN_URB        4
  46
  47 /* Number of CPort OUT urbs in flight at any point in time.
  48  * Adjust if we get messages saying we are out of urbs in the system log.
  49  */
  50 #define NUM_CPORT_OUT_URB       (8 * NUM_BULKS)
  51
  52 /*
  53  * @endpoint: bulk in endpoint for CPort data
  54  * @urb: array of urbs for the CPort in messages
  55  * @buffer: array of buffers for the @cport_in_urb urbs
  56  */
  57 struct es2_cport_in {
  58         __u8 endpoint;
  59         struct urb *urb[NUM_CPORT_IN_URB];
  60         u8 *buffer[NUM_CPORT_IN_URB];
  61 };
  62
  63 /*
  64  * @endpoint: bulk out endpoint for CPort data
  65  */
  66 struct es2_cport_out {
  67         __u8 endpoint;
  68 };
  69
  70 /**
  71  * es2_ap_dev - ES2 USB Bridge to AP structure
  72  * @usb_dev: pointer to the USB device we are.
  73  * @usb_intf: pointer to the USB interface we are bound to.
  74  * @hd: pointer to our gb_host_device structure
  75
  76  * @cport_in: endpoint, urbs and buffer for cport in messages
  77  * @cport_out: endpoint for for cport out messages
  78  * @cport_out_urb: array of urbs for the CPort out messages
  79  * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or
  80  *                      not.
  81  * @cport_out_urb_cancelled: array of flags indicating whether the
  82  *                      corresponding @cport_out_urb is being cancelled
  83  * @cport_out_urb_lock: locks the @cport_out_urb_busy "list"
  84  *
  85  * @apb_log_task: task pointer for logging thread
  86  * @apb_log_dentry: file system entry for the log file interface
  87  * @apb_log_enable_dentry: file system entry for enabling logging
  88  * @apb_log_fifo: kernel FIFO to carry logged data
  89  */
  90 struct es2_ap_dev {
  91         struct usb_device *usb_dev;
  92         struct usb_interface *usb_intf;
  93         struct gb_host_device *hd;
  94
  95         struct es2_cport_in cport_in[NUM_BULKS];
  96         struct es2_cport_out cport_out[NUM_BULKS];
  97         struct urb *cport_out_urb[NUM_CPORT_OUT_URB];
  98         bool cport_out_urb_busy[NUM_CPORT_OUT_URB];
  99         bool cport_out_urb_cancelled[NUM_CPORT_OUT_URB];
 100         spinlock_t cport_out_urb_lock;
 101
 102         int *cport_to_ep;
 103
 104         struct task_struct *apb_log_task;
 105         struct dentry *apb_log_dentry;
 106         struct dentry *apb_log_enable_dentry;
 107         DECLARE_KFIFO(apb_log_fifo, char, APB1_LOG_SIZE);
 108 };
 109
 110 /**
 111  * cport_to_ep - information about cport to endpoints mapping
 112  * @cport_id: the id of cport to map to endpoints
 113  * @endpoint_in: the endpoint number to use for in transfer
 114  * @endpoint_out: he endpoint number to use for out transfer
 115  */
 116 struct cport_to_ep {
 117         __le16 cport_id;
 118         __u8 endpoint_in;
 119         __u8 endpoint_out;
 120 };
 121
 122 static inline struct es2_ap_dev *hd_to_es2(struct gb_host_device *hd)
 123 {
 124         return (struct es2_ap_dev *)&hd->hd_priv;
 125 }
 126
 127 static void cport_out_callback(struct urb *urb);
 128 static void usb_log_enable(struct es2_ap_dev *es2);
 129 static void usb_log_disable(struct es2_ap_dev *es2);
 130
 131 /* Get the endpoints pair mapped to the cport */
 132 static int cport_to_ep_pair(struct es2_ap_dev *es2, u16 cport_id)
 133 {
 134         if (cport_id >= es2->hd->num_cports)
 135                 return 0;
 136         return es2->cport_to_ep[cport_id];
 137 }
 138
 139 #define ES2_TIMEOUT     500     /* 500 ms for the SVC to do something */
 140
 141 /* Disable for now until we work all of this out to keep a warning-free build */
 142 #if 0
 143 /* Test if the endpoints pair is already mapped to a cport */
 144 static int ep_pair_in_use(struct es2_ap_dev *es2, int ep_pair)
 145 {
 146         int i;
 147
 148         for (i = 0; i < es2->hd->num_cports; i++) {
 149                 if (es2->cport_to_ep[i] == ep_pair)
 150                         return 1;
 151         }
 152         return 0;
 153 }
 154
 155 /* Configure the endpoint mapping and send the request to APBridge */
 156 static int map_cport_to_ep(struct es2_ap_dev *es2,
 157                                 u16 cport_id, int ep_pair)
 158 {
 159         int retval;
 160         struct cport_to_ep *cport_to_ep;
 161
 162         if (ep_pair < 0 || ep_pair >= NUM_BULKS)
 163                 return -EINVAL;
 164         if (cport_id >= es2->hd->num_cports)
 165                 return -EINVAL;
 166         if (ep_pair && ep_pair_in_use(es2, ep_pair))
 167                 return -EINVAL;
 168
 169         cport_to_ep = kmalloc(sizeof(*cport_to_ep), GFP_KERNEL);
 170         if (!cport_to_ep)
 171                 return -ENOMEM;
 172
 173         es2->cport_to_ep[cport_id] = ep_pair;
 174         cport_to_ep->cport_id = cpu_to_le16(cport_id);
 175         cport_to_ep->endpoint_in = es2->cport_in[ep_pair].endpoint;
 176         cport_to_ep->endpoint_out = es2->cport_out[ep_pair].endpoint;
 177
 178         retval = usb_control_msg(es2->usb_dev,
 179                                  usb_sndctrlpipe(es2->usb_dev, 0),
 180                                  GB_APB_REQUEST_EP_MAPPING,
 181                                  USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 182                                  0x00, 0x00,
 183                                  (char *)cport_to_ep,
 184                                  sizeof(*cport_to_ep),
 185                                  ES2_TIMEOUT);
 186         if (retval == sizeof(*cport_to_ep))
 187                 retval = 0;
 188         kfree(cport_to_ep);
 189
 190         return retval;
 191 }
 192
 193 /* Unmap a cport: use the muxed endpoints pair */
 194 static int unmap_cport(struct es2_ap_dev *es2, u16 cport_id)
 195 {
 196         return map_cport_to_ep(es2, cport_id, 0);
 197 }
 198 #endif
 199
 200 static int output_sync(struct es2_ap_dev *es2, void *req, u16 size, u8 cmd)
 201 {
 202         struct usb_device *udev = es2->usb_dev;
 203         u8 *data;
 204         int retval;
 205
 206         data = kmalloc(size, GFP_KERNEL);
 207         if (!data)
 208                 return -ENOMEM;
 209         memcpy(data, req, size);
 210
 211         retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 212                                  cmd,
 213                                  USB_DIR_OUT | USB_TYPE_VENDOR |
 214                                  USB_RECIP_INTERFACE,
 215                                  0, 0, data, size, ES2_TIMEOUT);
 216         if (retval < 0)
 217                 dev_err(&udev->dev, "%s: return error %d\n", __func__, retval);
 218         else
 219                 retval = 0;
 220
 221         kfree(data);
 222         return retval;
 223 }
 224
 225 static void ap_urb_complete(struct urb *urb)
 226 {
 227         struct usb_ctrlrequest *dr = urb->context;
 228
 229         kfree(dr);
 230         usb_free_urb(urb);
 231 }
 232
 233 static int output_async(struct es2_ap_dev *es2, void *req, u16 size, u8 cmd)
 234 {
 235         struct usb_device *udev = es2->usb_dev;
 236         struct urb *urb;
 237         struct usb_ctrlrequest *dr;
 238         u8 *buf;
 239         int retval;
 240
 241         urb = usb_alloc_urb(0, GFP_ATOMIC);
 242         if (!urb)
 243                 return -ENOMEM;
 244
 245         dr = kmalloc(sizeof(*dr) + size, GFP_ATOMIC);
 246         if (!dr) {
 247                 usb_free_urb(urb);
 248                 return -ENOMEM;
 249         }
 250
 251         buf = (u8 *)dr + sizeof(*dr);
 252         memcpy(buf, req, size);
 253
 254         dr->bRequest = cmd;
 255         dr->bRequestType = USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE;
 256         dr->wValue = 0;
 257         dr->wIndex = 0;
 258         dr->wLength = cpu_to_le16(size);
 259
 260         usb_fill_control_urb(urb, udev, usb_sndctrlpipe(udev, 0),
 261                              (unsigned char *)dr, buf, size,
 262                              ap_urb_complete, dr);
 263         retval = usb_submit_urb(urb, GFP_ATOMIC);
 264         if (retval) {
 265                 usb_free_urb(urb);
 266                 kfree(dr);
 267         }
 268         return retval;
 269 }
 270
 271 static int output(struct gb_host_device *hd, void *req, u16 size, u8 cmd,
 272                      bool async)
 273 {
 274         struct es2_ap_dev *es2 = hd_to_es2(hd);
 275
 276         if (async)
 277                 return output_async(es2, req, size, cmd);
 278
 279         return output_sync(es2, req, size, cmd);
 280 }
 281
 282 static int es2_cport_in_enable(struct es2_ap_dev *es2,
 283                                 struct es2_cport_in *cport_in)
 284 {
 285         struct urb *urb;
 286         int ret;
 287         int i;
 288
 289         for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
 290                 urb = cport_in->urb[i];
 291
 292                 ret = usb_submit_urb(urb, GFP_KERNEL);
 293                 if (ret) {
 294                         dev_err(&es2->usb_dev->dev,
 295                                         "failed to submit in-urb: %d\n", ret);
 296                         goto err_kill_urbs;
 297                 }
 298         }
 299
 300         return 0;
 301
 302 err_kill_urbs:
 303         for (--i; i >= 0; --i) {
 304                 urb = cport_in->urb[i];
 305                 usb_kill_urb(urb);
 306         }
 307
 308         return ret;
 309 }
 310
 311 static void es2_cport_in_disable(struct es2_ap_dev *es2,
 312                                 struct es2_cport_in *cport_in)
 313 {
 314         struct urb *urb;
 315         int i;
 316
 317         for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
 318                 urb = cport_in->urb[i];
 319                 usb_kill_urb(urb);
 320         }
 321 }
 322
 323 static struct urb *next_free_urb(struct es2_ap_dev *es2, gfp_t gfp_mask)
 324 {
 325         struct urb *urb = NULL;
 326         unsigned long flags;
 327         int i;
 328
 329         spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
 330
 331         /* Look in our pool of allocated urbs first, as that's the "fastest" */
 332         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 333                 if (es2->cport_out_urb_busy[i] == false &&
 334                                 es2->cport_out_urb_cancelled[i] == false) {
 335                         es2->cport_out_urb_busy[i] = true;
 336                         urb = es2->cport_out_urb[i];
 337                         break;
 338                 }
 339         }
 340         spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
 341         if (urb)
 342                 return urb;
 343
 344         /*
 345          * Crap, pool is empty, complain to the syslog and go allocate one
 346          * dynamically as we have to succeed.
 347          */
 348         dev_dbg(&es2->usb_dev->dev,
 349                 "No free CPort OUT urbs, having to dynamically allocate one!\n");
 350         return usb_alloc_urb(0, gfp_mask);
 351 }
 352
 353 static void free_urb(struct es2_ap_dev *es2, struct urb *urb)
 354 {
 355         unsigned long flags;
 356         int i;
 357         /*
 358          * See if this was an urb in our pool, if so mark it "free", otherwise
 359          * we need to free it ourselves.
 360          */
 361         spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
 362         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 363                 if (urb == es2->cport_out_urb[i]) {
 364                         es2->cport_out_urb_busy[i] = false;
 365                         urb = NULL;
 366                         break;
 367                 }
 368         }
 369         spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
 370
 371         /* If urb is not NULL, then we need to free this urb */
 372         usb_free_urb(urb);
 373 }
 374
 375 /*
 376  * We (ab)use the operation-message header pad bytes to transfer the
 377  * cport id in order to minimise overhead.
 378  */
 379 static void
 380 gb_message_cport_pack(struct gb_operation_msg_hdr *header, u16 cport_id)
 381 {
 382         header->pad[0] = cport_id;
 383 }
 384
 385 /* Clear the pad bytes used for the CPort id */
 386 static void gb_message_cport_clear(struct gb_operation_msg_hdr *header)
 387 {
 388         header->pad[0] = 0;
 389 }
 390
 391 /* Extract the CPort id packed into the header, and clear it */
 392 static u16 gb_message_cport_unpack(struct gb_operation_msg_hdr *header)
 393 {
 394         u16 cport_id = header->pad[0];
 395
 396         gb_message_cport_clear(header);
 397
 398         return cport_id;
 399 }
 400
 401 /*
 402  * Returns zero if the message was successfully queued, or a negative errno
 403  * otherwise.
 404  */
 405 static int message_send(struct gb_host_device *hd, u16 cport_id,
 406                         struct gb_message *message, gfp_t gfp_mask)
 407 {
 408         struct es2_ap_dev *es2 = hd_to_es2(hd);
 409         struct usb_device *udev = es2->usb_dev;
 410         size_t buffer_size;
 411         int retval;
 412         struct urb *urb;
 413         int ep_pair;
 414         unsigned long flags;
 415
 416         /*
 417          * The data actually transferred will include an indication
 418          * of where the data should be sent.  Do one last check of
 419          * the target CPort id before filling it in.
 420          */
 421         if (!cport_id_valid(hd, cport_id)) {
 422                 dev_err(&udev->dev, "invalid cport %u\n", cport_id);
 423                 return -EINVAL;
 424         }
 425
 426         /* Find a free urb */
 427         urb = next_free_urb(es2, gfp_mask);
 428         if (!urb)
 429                 return -ENOMEM;
 430
 431         spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
 432         message->hcpriv = urb;
 433         spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
 434
 435         /* Pack the cport id into the message header */
 436         gb_message_cport_pack(message->header, cport_id);
 437
 438         buffer_size = sizeof(*message->header) + message->payload_size;
 439
 440         ep_pair = cport_to_ep_pair(es2, cport_id);
 441         usb_fill_bulk_urb(urb, udev,
 442                           usb_sndbulkpipe(udev,
 443                                           es2->cport_out[ep_pair].endpoint),
 444                           message->buffer, buffer_size,
 445                           cport_out_callback, message);
 446         urb->transfer_flags |= URB_ZERO_PACKET;
 447         trace_gb_host_device_send(hd, cport_id, buffer_size);
 448         retval = usb_submit_urb(urb, gfp_mask);
 449         if (retval) {
 450                 dev_err(&udev->dev, "failed to submit out-urb: %d\n", retval);
 451
 452                 spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
 453                 message->hcpriv = NULL;
 454                 spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
 455
 456                 free_urb(es2, urb);
 457                 gb_message_cport_clear(message->header);
 458
 459                 return retval;
 460         }
 461
 462         return 0;
 463 }
 464
 465 /*
 466  * Can not be called in atomic context.
 467  */
 468 static void message_cancel(struct gb_message *message)
 469 {
 470         struct gb_host_device *hd = message->operation->connection->hd;
 471         struct es2_ap_dev *es2 = hd_to_es2(hd);
 472         struct urb *urb;
 473         int i;
 474
 475         might_sleep();
 476
 477         spin_lock_irq(&es2->cport_out_urb_lock);
 478         urb = message->hcpriv;
 479
 480         /* Prevent dynamically allocated urb from being deallocated. */
 481         usb_get_urb(urb);
 482
 483         /* Prevent pre-allocated urb from being reused. */
 484         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 485                 if (urb == es2->cport_out_urb[i]) {
 486                         es2->cport_out_urb_cancelled[i] = true;
 487                         break;
 488                 }
 489         }
 490         spin_unlock_irq(&es2->cport_out_urb_lock);
 491
 492         usb_kill_urb(urb);
 493
 494         if (i < NUM_CPORT_OUT_URB) {
 495                 spin_lock_irq(&es2->cport_out_urb_lock);
 496                 es2->cport_out_urb_cancelled[i] = false;
 497                 spin_unlock_irq(&es2->cport_out_urb_lock);
 498         }
 499
 500         usb_free_urb(urb);
 501 }
 502
 503 static int cport_reset(struct gb_host_device *hd, u16 cport_id)
 504 {
 505         struct es2_ap_dev *es2 = hd_to_es2(hd);
 506         struct usb_device *udev = es2->usb_dev;
 507         int retval;
 508
 509         retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 510                                  GB_APB_REQUEST_RESET_CPORT,
 511                                  USB_DIR_OUT | USB_TYPE_VENDOR |
 512                                  USB_RECIP_INTERFACE, cport_id, 0,
 513                                  NULL, 0, ES2_TIMEOUT);
 514         if (retval < 0) {
 515                 dev_err(&udev->dev, "failed to reset cport %u: %d\n", cport_id,
 516                         retval);
 517                 return retval;
 518         }
 519
 520         return 0;
 521 }
 522
 523 static int cport_enable(struct gb_host_device *hd, u16 cport_id)
 524 {
 525         int retval;
 526
 527         if (cport_id != GB_SVC_CPORT_ID) {
 528                 retval = cport_reset(hd, cport_id);
 529                 if (retval)
 530                         return retval;
 531         }
 532
 533         return 0;
 534 }
 535
 536 static int latency_tag_enable(struct gb_host_device *hd, u16 cport_id)
 537 {
 538         int retval;
 539         struct es2_ap_dev *es2 = hd_to_es2(hd);
 540         struct usb_device *udev = es2->usb_dev;
 541
 542         if (!cport_id_valid(hd, cport_id)) {
 543                 dev_err(&udev->dev, "invalid cport %u\n", cport_id);
 544                 return -EINVAL;
 545         }
 546
 547         retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 548                                  GB_APB_REQUEST_LATENCY_TAG_EN,
 549                                  USB_DIR_OUT | USB_TYPE_VENDOR |
 550                                  USB_RECIP_INTERFACE, cport_id, 0, NULL,
 551                                  0, ES2_TIMEOUT);
 552
 553         if (retval < 0)
 554                 dev_err(&udev->dev, "Cannot enable latency tag for cport %d\n",
 555                         cport_id);
 556         return retval;
 557 }
 558
 559 static int latency_tag_disable(struct gb_host_device *hd, u16 cport_id)
 560 {
 561         int retval;
 562         struct es2_ap_dev *es2 = hd_to_es2(hd);
 563         struct usb_device *udev = es2->usb_dev;
 564
 565         if (!cport_id_valid(hd, cport_id)) {
 566                 dev_err(&udev->dev, "invalid cport %u\n", cport_id);
 567                 return -EINVAL;
 568         }
 569
 570         retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 571                                  GB_APB_REQUEST_LATENCY_TAG_DIS,
 572                                  USB_DIR_OUT | USB_TYPE_VENDOR |
 573                                  USB_RECIP_INTERFACE, cport_id, 0, NULL,
 574                                  0, ES2_TIMEOUT);
 575
 576         if (retval < 0)
 577                 dev_err(&udev->dev, "Cannot disable latency tag for cport %d\n",
 578                         cport_id);
 579         return retval;
 580 }
 581
 582 static int cport_features_enable(struct gb_host_device *hd, u16 cport_id)
 583 {
 584         int retval;
 585         struct es2_ap_dev *es2 = hd_to_es2(hd);
 586         struct usb_device *udev = es2->usb_dev;
 587
 588         retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 589                                  GB_APB_REQUEST_CPORT_FEAT_EN,
 590                                  USB_DIR_OUT | USB_TYPE_VENDOR |
 591                                  USB_RECIP_INTERFACE, cport_id, 0, NULL,
 592                                  0, ES2_TIMEOUT);
 593         if (retval < 0)
 594                 dev_err(&udev->dev, "Cannot enable CPort features for cport %u: %d\n",
 595                         cport_id, retval);
 596         return retval;
 597 }
 598
 599 static int cport_features_disable(struct gb_host_device *hd, u16 cport_id)
 600 {
 601         int retval;
 602         struct es2_ap_dev *es2 = hd_to_es2(hd);
 603         struct usb_device *udev = es2->usb_dev;
 604
 605         retval = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 606                                  GB_APB_REQUEST_CPORT_FEAT_DIS,
 607                                  USB_DIR_OUT | USB_TYPE_VENDOR |
 608                                  USB_RECIP_INTERFACE, cport_id, 0, NULL,
 609                                  0, ES2_TIMEOUT);
 610         if (retval < 0)
 611                 dev_err(&udev->dev,
 612                         "Cannot disable CPort features for cport %u: %d\n",
 613                         cport_id, retval);
 614         return retval;
 615 }
 616
 617 static struct gb_hd_driver es2_driver = {
 618         .hd_priv_size           = sizeof(struct es2_ap_dev),
 619         .message_send           = message_send,
 620         .message_cancel         = message_cancel,
 621         .cport_enable           = cport_enable,
 622         .latency_tag_enable     = latency_tag_enable,
 623         .latency_tag_disable    = latency_tag_disable,
 624         .output                 = output,
 625         .cport_features_enable  = cport_features_enable,
 626         .cport_features_disable = cport_features_disable,
 627 };
 628
 629 /* Common function to report consistent warnings based on URB status */
 630 static int check_urb_status(struct urb *urb)
 631 {
 632         struct device *dev = &urb->dev->dev;
 633         int status = urb->status;
 634
 635         switch (status) {
 636         case 0:
 637                 return 0;
 638
 639         case -EOVERFLOW:
 640                 dev_err(dev, "%s: overflow actual length is %d\n",
 641                         __func__, urb->actual_length);
 642         case -ECONNRESET:
 643         case -ENOENT:
 644         case -ESHUTDOWN:
 645         case -EILSEQ:
 646         case -EPROTO:
 647                 /* device is gone, stop sending */
 648                 return status;
 649         }
 650         dev_err(dev, "%s: unknown status %d\n", __func__, status);
 651
 652         return -EAGAIN;
 653 }
 654
 655 static void es2_destroy(struct es2_ap_dev *es2)
 656 {
 657         struct usb_device *udev;
 658         int bulk_in;
 659         int i;
 660
 661         debugfs_remove(es2->apb_log_enable_dentry);
 662         usb_log_disable(es2);
 663
 664         /* Tear down everything! */
 665         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 666                 struct urb *urb = es2->cport_out_urb[i];
 667
 668                 if (!urb)
 669                         break;
 670                 usb_kill_urb(urb);
 671                 usb_free_urb(urb);
 672                 es2->cport_out_urb[i] = NULL;
 673                 es2->cport_out_urb_busy[i] = false;     /* just to be anal */
 674         }
 675
 676         for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
 677                 struct es2_cport_in *cport_in = &es2->cport_in[bulk_in];
 678
 679                 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
 680                         struct urb *urb = cport_in->urb[i];
 681
 682                         if (!urb)
 683                                 break;
 684                         usb_free_urb(urb);
 685                         kfree(cport_in->buffer[i]);
 686                         cport_in->buffer[i] = NULL;
 687                 }
 688         }
 689
 690         kfree(es2->cport_to_ep);
 691
 692         udev = es2->usb_dev;
 693         gb_hd_put(es2->hd);
 694
 695         usb_put_dev(udev);
 696 }
 697
 698 static void cport_in_callback(struct urb *urb)
 699 {
 700         struct gb_host_device *hd = urb->context;
 701         struct device *dev = &urb->dev->dev;
 702         struct gb_operation_msg_hdr *header;
 703         int status = check_urb_status(urb);
 704         int retval;
 705         u16 cport_id;
 706
 707         if (status) {
 708                 if ((status == -EAGAIN) || (status == -EPROTO))
 709                         goto exit;
 710
 711                 /* The urb is being unlinked */
 712                 if (status == -ENOENT || status == -ESHUTDOWN)
 713                         return;
 714
 715                 dev_err(dev, "urb cport in error %d (dropped)\n", status);
 716                 return;
 717         }
 718
 719         if (urb->actual_length < sizeof(*header)) {
 720                 dev_err(dev, "short message received\n");
 721                 goto exit;
 722         }
 723
 724         /* Extract the CPort id, which is packed in the message header */
 725         header = urb->transfer_buffer;
 726         cport_id = gb_message_cport_unpack(header);
 727
 728         if (cport_id_valid(hd, cport_id)) {
 729                 trace_gb_host_device_recv(hd, cport_id, urb->actual_length);
 730                 greybus_data_rcvd(hd, cport_id, urb->transfer_buffer,
 731                                                         urb->actual_length);
 732         } else {
 733                 dev_err(dev, "invalid cport id %u received\n", cport_id);
 734         }
 735 exit:
 736         /* put our urb back in the request pool */
 737         retval = usb_submit_urb(urb, GFP_ATOMIC);
 738         if (retval)
 739                 dev_err(dev, "failed to resubmit in-urb: %d\n", retval);
 740 }
 741
 742 static void cport_out_callback(struct urb *urb)
 743 {
 744         struct gb_message *message = urb->context;
 745         struct gb_host_device *hd = message->operation->connection->hd;
 746         struct es2_ap_dev *es2 = hd_to_es2(hd);
 747         int status = check_urb_status(urb);
 748         unsigned long flags;
 749
 750         gb_message_cport_clear(message->header);
 751
 752         spin_lock_irqsave(&es2->cport_out_urb_lock, flags);
 753         message->hcpriv = NULL;
 754         spin_unlock_irqrestore(&es2->cport_out_urb_lock, flags);
 755
 756         /*
 757          * Tell the submitter that the message send (attempt) is
 758          * complete, and report the status.
 759          */
 760         greybus_message_sent(hd, message, status);
 761
 762         free_urb(es2, urb);
 763 }
 764
 765 #define APB1_LOG_MSG_SIZE       64
 766 static void apb_log_get(struct es2_ap_dev *es2, char *buf)
 767 {
 768         int retval;
 769
 770         /* SVC messages go down our control pipe */
 771         do {
 772                 retval = usb_control_msg(es2->usb_dev,
 773                                         usb_rcvctrlpipe(es2->usb_dev, 0),
 774                                         GB_APB_REQUEST_LOG,
 775                                         USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 776                                         0x00, 0x00,
 777                                         buf,
 778                                         APB1_LOG_MSG_SIZE,
 779                                         ES2_TIMEOUT);
 780                 if (retval > 0)
 781                         kfifo_in(&es2->apb_log_fifo, buf, retval);
 782         } while (retval > 0);
 783 }
 784
 785 static int apb_log_poll(void *data)
 786 {
 787         struct es2_ap_dev *es2 = data;
 788         char *buf;
 789
 790         buf = kmalloc(APB1_LOG_MSG_SIZE, GFP_KERNEL);
 791         if (!buf)
 792                 return -ENOMEM;
 793
 794         while (!kthread_should_stop()) {
 795                 msleep(1000);
 796                 apb_log_get(es2, buf);
 797         }
 798
 799         kfree(buf);
 800
 801         return 0;
 802 }
 803
 804 static ssize_t apb_log_read(struct file *f, char __user *buf,
 805                                 size_t count, loff_t *ppos)
 806 {
 807         struct es2_ap_dev *es2 = f->f_inode->i_private;
 808         ssize_t ret;
 809         size_t copied;
 810         char *tmp_buf;
 811
 812         if (count > APB1_LOG_SIZE)
 813                 count = APB1_LOG_SIZE;
 814
 815         tmp_buf = kmalloc(count, GFP_KERNEL);
 816         if (!tmp_buf)
 817                 return -ENOMEM;
 818
 819         copied = kfifo_out(&es2->apb_log_fifo, tmp_buf, count);
 820         ret = simple_read_from_buffer(buf, count, ppos, tmp_buf, copied);
 821
 822         kfree(tmp_buf);
 823
 824         return ret;
 825 }
 826
 827 static const struct file_operations apb_log_fops = {
 828         .read   = apb_log_read,
 829 };
 830
 831 static void usb_log_enable(struct es2_ap_dev *es2)
 832 {
 833         if (!IS_ERR_OR_NULL(es2->apb_log_task))
 834                 return;
 835
 836         /* get log from APB1 */
 837         es2->apb_log_task = kthread_run(apb_log_poll, es2, "apb_log");
 838         if (IS_ERR(es2->apb_log_task))
 839                 return;
 840         /* XXX We will need to rename this per APB */
 841         es2->apb_log_dentry = debugfs_create_file("apb_log", S_IRUGO,
 842                                                 gb_debugfs_get(), es2,
 843                                                 &apb_log_fops);
 844 }
 845
 846 static void usb_log_disable(struct es2_ap_dev *es2)
 847 {
 848         if (IS_ERR_OR_NULL(es2->apb_log_task))
 849                 return;
 850
 851         debugfs_remove(es2->apb_log_dentry);
 852         es2->apb_log_dentry = NULL;
 853
 854         kthread_stop(es2->apb_log_task);
 855         es2->apb_log_task = NULL;
 856 }
 857
 858 static ssize_t apb_log_enable_read(struct file *f, char __user *buf,
 859                                 size_t count, loff_t *ppos)
 860 {
 861         struct es2_ap_dev *es2 = f->f_inode->i_private;
 862         int enable = !IS_ERR_OR_NULL(es2->apb_log_task);
 863         char tmp_buf[3];
 864
 865         sprintf(tmp_buf, "%d\n", enable);
 866         return simple_read_from_buffer(buf, count, ppos, tmp_buf, 3);
 867 }
 868
 869 static ssize_t apb_log_enable_write(struct file *f, const char __user *buf,
 870                                 size_t count, loff_t *ppos)
 871 {
 872         int enable;
 873         ssize_t retval;
 874         struct es2_ap_dev *es2 = f->f_inode->i_private;
 875
 876         retval = kstrtoint_from_user(buf, count, 10, &enable);
 877         if (retval)
 878                 return retval;
 879
 880         if (enable)
 881                 usb_log_enable(es2);
 882         else
 883                 usb_log_disable(es2);
 884
 885         return count;
 886 }
 887
 888 static const struct file_operations apb_log_enable_fops = {
 889         .read   = apb_log_enable_read,
 890         .write  = apb_log_enable_write,
 891 };
 892
 893 static int apb_get_cport_count(struct usb_device *udev)
 894 {
 895         int retval;
 896         __le16 *cport_count;
 897
 898         cport_count = kzalloc(sizeof(*cport_count), GFP_KERNEL);
 899         if (!cport_count)
 900                 return -ENOMEM;
 901
 902         retval = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 903                                  GB_APB_REQUEST_CPORT_COUNT,
 904                                  USB_DIR_IN | USB_TYPE_VENDOR |
 905                                  USB_RECIP_INTERFACE, 0, 0, cport_count,
 906                                  sizeof(*cport_count), ES2_TIMEOUT);
 907         if (retval != sizeof(*cport_count)) {
 908                 dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
 909                         retval);
 910
 911                 if (retval >= 0)
 912                         retval = -EIO;
 913
 914                 goto out;
 915         }
 916
 917         retval = le16_to_cpu(*cport_count);
 918
 919         /* We need to fit a CPort ID in one byte of a message header */
 920         if (retval > U8_MAX) {
 921                 retval = U8_MAX;
 922                 dev_warn(&udev->dev, "Limiting number of CPorts to U8_MAX\n");
 923         }
 924
 925 out:
 926         kfree(cport_count);
 927         return retval;
 928 }
 929
 930 /*
 931  * The ES2 USB Bridge device has 15 endpoints
 932  * 1 Control - usual USB stuff + AP -> APBridgeA messages
 933  * 7 Bulk IN - CPort data in
 934  * 7 Bulk OUT - CPort data out
 935  */
 936 static int ap_probe(struct usb_interface *interface,
 937                     const struct usb_device_id *id)
 938 {
 939         struct es2_ap_dev *es2;
 940         struct gb_host_device *hd;
 941         struct usb_device *udev;
 942         struct usb_host_interface *iface_desc;
 943         struct usb_endpoint_descriptor *endpoint;
 944         int bulk_in = 0;
 945         int bulk_out = 0;
 946         int retval;
 947         int i;
 948         int num_cports;
 949
 950         udev = usb_get_dev(interface_to_usbdev(interface));
 951
 952         num_cports = apb_get_cport_count(udev);
 953         if (num_cports < 0) {
 954                 usb_put_dev(udev);
 955                 dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
 956                         num_cports);
 957                 return num_cports;
 958         }
 959
 960         hd = gb_hd_create(&es2_driver, &udev->dev, ES2_GBUF_MSG_SIZE_MAX,
 961                                 num_cports);
 962         if (IS_ERR(hd)) {
 963                 usb_put_dev(udev);
 964                 return PTR_ERR(hd);
 965         }
 966
 967         es2 = hd_to_es2(hd);
 968         es2->hd = hd;
 969         es2->usb_intf = interface;
 970         es2->usb_dev = udev;
 971         spin_lock_init(&es2->cport_out_urb_lock);
 972         INIT_KFIFO(es2->apb_log_fifo);
 973         usb_set_intfdata(interface, es2);
 974
 975         /*
 976          * Reserve the CDSI0 and CDSI1 CPorts so they won't be allocated
 977          * dynamically.
 978          */
 979         retval = gb_hd_cport_reserve(hd, ES2_CPORT_CDSI0);
 980         if (retval)
 981                 goto error;
 982         retval = gb_hd_cport_reserve(hd, ES2_CPORT_CDSI1);
 983         if (retval)
 984                 goto error;
 985
 986         es2->cport_to_ep = kcalloc(hd->num_cports, sizeof(*es2->cport_to_ep),
 987                                    GFP_KERNEL);
 988         if (!es2->cport_to_ep) {
 989                 retval = -ENOMEM;
 990                 goto error;
 991         }
 992
 993         /* find all bulk endpoints */
 994         iface_desc = interface->cur_altsetting;
 995         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 996                 endpoint = &iface_desc->endpoint[i].desc;
 997
 998                 if (usb_endpoint_is_bulk_in(endpoint)) {
 999                         es2->cport_in[bulk_in++].endpoint =
1000                                 endpoint->bEndpointAddress;
1001                 } else if (usb_endpoint_is_bulk_out(endpoint)) {
1002                         es2->cport_out[bulk_out++].endpoint =
1003                                 endpoint->bEndpointAddress;
1004                 } else {
1005                         dev_err(&udev->dev,
1006                                 "Unknown endpoint type found, address 0x%02x\n",
1007                                 endpoint->bEndpointAddress);
1008                 }
1009         }
1010         if (bulk_in != NUM_BULKS || bulk_out != NUM_BULKS) {
1011                 dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n");
1012                 retval = -ENODEV;
1013                 goto error;
1014         }
1015
1016         /* Allocate buffers for our cport in messages */
1017         for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
1018                 struct es2_cport_in *cport_in = &es2->cport_in[bulk_in];
1019
1020                 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
1021                         struct urb *urb;
1022                         u8 *buffer;
1023
1024                         urb = usb_alloc_urb(0, GFP_KERNEL);
1025                         if (!urb) {
1026                                 retval = -ENOMEM;
1027                                 goto error;
1028                         }
1029                         buffer = kmalloc(ES2_GBUF_MSG_SIZE_MAX, GFP_KERNEL);
1030                         if (!buffer) {
1031                                 retval = -ENOMEM;
1032                                 goto error;
1033                         }
1034
1035                         usb_fill_bulk_urb(urb, udev,
1036                                           usb_rcvbulkpipe(udev,
1037                                                           cport_in->endpoint),
1038                                           buffer, ES2_GBUF_MSG_SIZE_MAX,
1039                                           cport_in_callback, hd);
1040                         cport_in->urb[i] = urb;
1041                         cport_in->buffer[i] = buffer;
1042                 }
1043         }
1044
1045         /* Allocate urbs for our CPort OUT messages */
1046         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
1047                 struct urb *urb;
1048
1049                 urb = usb_alloc_urb(0, GFP_KERNEL);
1050                 if (!urb) {
1051                         retval = -ENOMEM;
1052                         goto error;
1053                 }
1054
1055                 es2->cport_out_urb[i] = urb;
1056                 es2->cport_out_urb_busy[i] = false;     /* just to be anal */
1057         }
1058
1059         /* XXX We will need to rename this per APB */
1060         es2->apb_log_enable_dentry = debugfs_create_file("apb_log_enable",
1061                                                         (S_IWUSR | S_IRUGO),
1062                                                         gb_debugfs_get(), es2,
1063                                                         &apb_log_enable_fops);
1064
1065         retval = gb_hd_add(hd);
1066         if (retval)
1067                 goto error;
1068
1069         for (i = 0; i < NUM_BULKS; ++i) {
1070                 retval = es2_cport_in_enable(es2, &es2->cport_in[i]);
1071                 if (retval)
1072                         goto err_disable_cport_in;
1073         }
1074
1075         return 0;
1076
1077 err_disable_cport_in:
1078         for (--i; i >= 0; --i)
1079                 es2_cport_in_disable(es2, &es2->cport_in[i]);
1080         gb_hd_del(hd);
1081 error:
1082         es2_destroy(es2);
1083
1084         return retval;
1085 }
1086
1087 static void ap_disconnect(struct usb_interface *interface)
1088 {
1089         struct es2_ap_dev *es2 = usb_get_intfdata(interface);
1090         int i;
1091
1092         gb_hd_del(es2->hd);
1093
1094         for (i = 0; i < NUM_BULKS; ++i)
1095                 es2_cport_in_disable(es2, &es2->cport_in[i]);
1096
1097         es2_destroy(es2);
1098 }
1099
1100 static struct usb_driver es2_ap_driver = {
1101         .name =         "es2_ap_driver",
1102         .probe =        ap_probe,
1103         .disconnect =   ap_disconnect,
1104         .id_table =     id_table,
1105         .soft_unbind =  1,
1106 };
1107
1108 module_usb_driver(es2_ap_driver);
1109
1110 MODULE_LICENSE("GPL v2");
1111 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");