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
  20 /* Memory sizes for the buffers sent to/from the ES1 controller */
  21 #define ES1_GBUF_MSG_SIZE_MAX   2048
  22
  23 static const struct usb_device_id id_table[] = {
  24         /* Made up numbers for the SVC USB Bridge in ES2 */
  25         { USB_DEVICE(0xffff, 0x0002) },
  26         { },
  27 };
  28 MODULE_DEVICE_TABLE(usb, id_table);
  29
  30 #define APB1_LOG_SIZE           SZ_16K
  31 static struct dentry *apb1_log_dentry;
  32 static struct dentry *apb1_log_enable_dentry;
  33 static struct task_struct *apb1_log_task;
  34 static DEFINE_KFIFO(apb1_log_fifo, char, APB1_LOG_SIZE);
  35
  36 /* Number of bulk in and bulk out couple */
  37 #define NUM_BULKS               7
  38
  39 /*
  40  * Number of CPort IN urbs in flight at any point in time.
  41  * Adjust if we are having stalls in the USB buffer due to not enough urbs in
  42  * flight.
  43  */
  44 #define NUM_CPORT_IN_URB        4
  45
  46 /* Number of CPort OUT urbs in flight at any point in time.
  47  * Adjust if we get messages saying we are out of urbs in the system log.
  48  */
  49 #define NUM_CPORT_OUT_URB       (8 * NUM_BULKS)
  50
  51 /* vendor request AP message */
  52 #define REQUEST_SVC             0x01
  53
  54 /* vendor request APB1 log */
  55 #define REQUEST_LOG             0x02
  56
  57 /* vendor request to map a cport to bulk in and bulk out endpoints */
  58 #define REQUEST_EP_MAPPING      0x03
  59
  60 /* vendor request to get the number of cports available */
  61 #define REQUEST_CPORT_COUNT     0x04
  62
  63 /*
  64  * @endpoint: bulk in endpoint for CPort data
  65  * @urb: array of urbs for the CPort in messages
  66  * @buffer: array of buffers for the @cport_in_urb urbs
  67  */
  68 struct es1_cport_in {
  69         __u8 endpoint;
  70         struct urb *urb[NUM_CPORT_IN_URB];
  71         u8 *buffer[NUM_CPORT_IN_URB];
  72 };
  73
  74 /*
  75  * @endpoint: bulk out endpoint for CPort data
  76  */
  77 struct es1_cport_out {
  78         __u8 endpoint;
  79 };
  80
  81 /**
  82  * es1_ap_dev - ES1 USB Bridge to AP structure
  83  * @usb_dev: pointer to the USB device we are.
  84  * @usb_intf: pointer to the USB interface we are bound to.
  85  * @hd: pointer to our greybus_host_device structure
  86
  87  * @cport_in: endpoint, urbs and buffer for cport in messages
  88  * @cport_out: endpoint for for cport out messages
  89  * @cport_out_urb: array of urbs for the CPort out messages
  90  * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or
  91  *                      not.
  92  * @cport_out_urb_cancelled: array of flags indicating whether the
  93  *                      corresponding @cport_out_urb is being cancelled
  94  * @cport_out_urb_lock: locks the @cport_out_urb_busy "list"
  95  */
  96 struct es1_ap_dev {
  97         struct usb_device *usb_dev;
  98         struct usb_interface *usb_intf;
  99         struct greybus_host_device *hd;
 100
 101         struct es1_cport_in cport_in[NUM_BULKS];
 102         struct es1_cport_out cport_out[NUM_BULKS];
 103         struct urb *cport_out_urb[NUM_CPORT_OUT_URB];
 104         bool cport_out_urb_busy[NUM_CPORT_OUT_URB];
 105         bool cport_out_urb_cancelled[NUM_CPORT_OUT_URB];
 106         spinlock_t cport_out_urb_lock;
 107
 108         int *cport_to_ep;
 109 };
 110
 111 struct cport_to_ep {
 112         __le16 cport_id;
 113         __u8 endpoint_in;
 114         __u8 endpoint_out;
 115 };
 116
 117 static inline struct es1_ap_dev *hd_to_es1(struct greybus_host_device *hd)
 118 {
 119         return (struct es1_ap_dev *)&hd->hd_priv;
 120 }
 121
 122 static void cport_out_callback(struct urb *urb);
 123 static void usb_log_enable(struct es1_ap_dev *es1);
 124 static void usb_log_disable(struct es1_ap_dev *es1);
 125
 126 static int cport_to_ep_pair(struct es1_ap_dev *es1, u16 cport_id)
 127 {
 128         if (cport_id >= es1->hd->num_cports)
 129                 return 0;
 130         return es1->cport_to_ep[cport_id];
 131 }
 132
 133 #define ES1_TIMEOUT     500     /* 500 ms for the SVC to do something */
 134
 135 static int ep_pair_in_use(struct es1_ap_dev *es1, int ep_pair)
 136 {
 137         int i;
 138
 139         for (i = 0; i < es1->hd->num_cports; i++) {
 140                 if (es1->cport_to_ep[i] == ep_pair)
 141                         return 1;
 142         }
 143         return 0;
 144 }
 145
 146 static int map_cport_to_ep(struct es1_ap_dev *es1,
 147                                 u16 cport_id, int ep_pair)
 148 {
 149         int retval;
 150         struct cport_to_ep *cport_to_ep;
 151
 152         if (ep_pair < 0 || ep_pair >= NUM_BULKS)
 153                 return -EINVAL;
 154         if (cport_id >= es1->hd->num_cports)
 155                 return -EINVAL;
 156         if (ep_pair && ep_pair_in_use(es1, ep_pair))
 157                 return -EINVAL;
 158
 159         cport_to_ep = kmalloc(sizeof(*cport_to_ep), GFP_KERNEL);
 160         if (!cport_to_ep)
 161                 return -ENOMEM;
 162
 163         es1->cport_to_ep[cport_id] = ep_pair;
 164         cport_to_ep->cport_id = cpu_to_le16(cport_id);
 165         cport_to_ep->endpoint_in = es1->cport_in[ep_pair].endpoint;
 166         cport_to_ep->endpoint_out = es1->cport_out[ep_pair].endpoint;
 167
 168         retval = usb_control_msg(es1->usb_dev,
 169                                  usb_sndctrlpipe(es1->usb_dev, 0),
 170                                  REQUEST_EP_MAPPING,
 171                                  USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 172                                  0x00, 0x00,
 173                                  (char *)cport_to_ep,
 174                                  sizeof(*cport_to_ep),
 175                                  ES1_TIMEOUT);
 176         if (retval == sizeof(*cport_to_ep))
 177                 retval = 0;
 178         kfree(cport_to_ep);
 179
 180         return retval;
 181 }
 182
 183 static int unmap_cport(struct es1_ap_dev *es1, u16 cport_id)
 184 {
 185         return map_cport_to_ep(es1, cport_id, 0);
 186 }
 187
 188 static struct urb *next_free_urb(struct es1_ap_dev *es1, gfp_t gfp_mask)
 189 {
 190         struct urb *urb = NULL;
 191         unsigned long flags;
 192         int i;
 193
 194         spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
 195
 196         /* Look in our pool of allocated urbs first, as that's the "fastest" */
 197         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 198                 if (es1->cport_out_urb_busy[i] == false &&
 199                                 es1->cport_out_urb_cancelled[i] == false) {
 200                         es1->cport_out_urb_busy[i] = true;
 201                         urb = es1->cport_out_urb[i];
 202                         break;
 203                 }
 204         }
 205         spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
 206         if (urb)
 207                 return urb;
 208
 209         /*
 210          * Crap, pool is empty, complain to the syslog and go allocate one
 211          * dynamically as we have to succeed.
 212          */
 213         dev_err(&es1->usb_dev->dev,
 214                 "No free CPort OUT urbs, having to dynamically allocate one!\n");
 215         return usb_alloc_urb(0, gfp_mask);
 216 }
 217
 218 static void free_urb(struct es1_ap_dev *es1, struct urb *urb)
 219 {
 220         unsigned long flags;
 221         int i;
 222         /*
 223          * See if this was an urb in our pool, if so mark it "free", otherwise
 224          * we need to free it ourselves.
 225          */
 226         spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
 227         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 228                 if (urb == es1->cport_out_urb[i]) {
 229                         es1->cport_out_urb_busy[i] = false;
 230                         urb = NULL;
 231                         break;
 232                 }
 233         }
 234         spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
 235
 236         /* If urb is not NULL, then we need to free this urb */
 237         usb_free_urb(urb);
 238 }
 239
 240 /*
 241  * We (ab)use the operation-message header pad bytes to transfer the
 242  * cport id in order to minimise overhead.
 243  */
 244 static void
 245 gb_message_cport_pack(struct gb_operation_msg_hdr *header, u16 cport_id)
 246 {
 247         header->pad[0] = cport_id;
 248 }
 249
 250 /* Clear the pad bytes used for the CPort id */
 251 static void gb_message_cport_clear(struct gb_operation_msg_hdr *header)
 252 {
 253         header->pad[0] = 0;
 254 }
 255
 256 /* Extract the CPort id packed into the header, and clear it */
 257 static u16 gb_message_cport_unpack(struct gb_operation_msg_hdr *header)
 258 {
 259         u16 cport_id = header->pad[0];
 260
 261         gb_message_cport_clear(header);
 262
 263         return cport_id;
 264 }
 265
 266 /*
 267  * Returns zero if the message was successfully queued, or a negative errno
 268  * otherwise.
 269  */
 270 static int message_send(struct greybus_host_device *hd, u16 cport_id,
 271                         struct gb_message *message, gfp_t gfp_mask)
 272 {
 273         struct es1_ap_dev *es1 = hd_to_es1(hd);
 274         struct usb_device *udev = es1->usb_dev;
 275         size_t buffer_size;
 276         int retval;
 277         struct urb *urb;
 278         int ep_pair;
 279         unsigned long flags;
 280
 281         /*
 282          * The data actually transferred will include an indication
 283          * of where the data should be sent.  Do one last check of
 284          * the target CPort id before filling it in.
 285          */
 286         if (!cport_id_valid(hd, cport_id)) {
 287                 pr_err("invalid destination cport 0x%02x\n", cport_id);
 288                 return -EINVAL;
 289         }
 290
 291         /* Find a free urb */
 292         urb = next_free_urb(es1, gfp_mask);
 293         if (!urb)
 294                 return -ENOMEM;
 295
 296         spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
 297         message->hcpriv = urb;
 298         spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
 299
 300         /* Pack the cport id into the message header */
 301         gb_message_cport_pack(message->header, cport_id);
 302
 303         buffer_size = sizeof(*message->header) + message->payload_size;
 304
 305         ep_pair = cport_to_ep_pair(es1, cport_id);
 306         usb_fill_bulk_urb(urb, udev,
 307                           usb_sndbulkpipe(udev,
 308                                           es1->cport_out[ep_pair].endpoint),
 309                           message->buffer, buffer_size,
 310                           cport_out_callback, message);
 311         urb->transfer_flags |= URB_ZERO_PACKET;
 312         gb_connection_push_timestamp(message->operation->connection);
 313         retval = usb_submit_urb(urb, gfp_mask);
 314         if (retval) {
 315                 pr_err("error %d submitting URB\n", retval);
 316
 317                 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
 318                 message->hcpriv = NULL;
 319                 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
 320
 321                 free_urb(es1, urb);
 322                 gb_message_cport_clear(message->header);
 323
 324                 return retval;
 325         }
 326
 327         return 0;
 328 }
 329
 330 /*
 331  * Can not be called in atomic context.
 332  */
 333 static void message_cancel(struct gb_message *message)
 334 {
 335         struct greybus_host_device *hd = message->operation->connection->hd;
 336         struct es1_ap_dev *es1 = hd_to_es1(hd);
 337         struct urb *urb;
 338         int i;
 339
 340         might_sleep();
 341
 342         spin_lock_irq(&es1->cport_out_urb_lock);
 343         urb = message->hcpriv;
 344
 345         /* Prevent dynamically allocated urb from being deallocated. */
 346         usb_get_urb(urb);
 347
 348         /* Prevent pre-allocated urb from being reused. */
 349         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 350                 if (urb == es1->cport_out_urb[i]) {
 351                         es1->cport_out_urb_cancelled[i] = true;
 352                         break;
 353                 }
 354         }
 355         spin_unlock_irq(&es1->cport_out_urb_lock);
 356
 357         usb_kill_urb(urb);
 358
 359         if (i < NUM_CPORT_OUT_URB) {
 360                 spin_lock_irq(&es1->cport_out_urb_lock);
 361                 es1->cport_out_urb_cancelled[i] = false;
 362                 spin_unlock_irq(&es1->cport_out_urb_lock);
 363         }
 364
 365         usb_free_urb(urb);
 366 }
 367
 368 static struct greybus_host_driver es1_driver = {
 369         .hd_priv_size           = sizeof(struct es1_ap_dev),
 370         .message_send           = message_send,
 371         .message_cancel         = message_cancel,
 372 };
 373
 374 /* Common function to report consistent warnings based on URB status */
 375 static int check_urb_status(struct urb *urb)
 376 {
 377         struct device *dev = &urb->dev->dev;
 378         int status = urb->status;
 379
 380         switch (status) {
 381         case 0:
 382                 return 0;
 383
 384         case -EOVERFLOW:
 385                 dev_err(dev, "%s: overflow actual length is %d\n",
 386                         __func__, urb->actual_length);
 387         case -ECONNRESET:
 388         case -ENOENT:
 389         case -ESHUTDOWN:
 390         case -EILSEQ:
 391         case -EPROTO:
 392                 /* device is gone, stop sending */
 393                 return status;
 394         }
 395         dev_err(dev, "%s: unknown status %d\n", __func__, status);
 396
 397         return -EAGAIN;
 398 }
 399
 400 static void ap_disconnect(struct usb_interface *interface)
 401 {
 402         struct es1_ap_dev *es1;
 403         struct usb_device *udev;
 404         int bulk_in;
 405         int i;
 406
 407         es1 = usb_get_intfdata(interface);
 408         if (!es1)
 409                 return;
 410
 411         usb_log_disable(es1);
 412
 413         /* Tear down everything! */
 414         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 415                 struct urb *urb = es1->cport_out_urb[i];
 416
 417                 if (!urb)
 418                         break;
 419                 usb_kill_urb(urb);
 420                 usb_free_urb(urb);
 421                 es1->cport_out_urb[i] = NULL;
 422                 es1->cport_out_urb_busy[i] = false;     /* just to be anal */
 423         }
 424
 425         for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
 426                 struct es1_cport_in *cport_in = &es1->cport_in[bulk_in];
 427                 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
 428                         struct urb *urb = cport_in->urb[i];
 429
 430                         if (!urb)
 431                                 break;
 432                         usb_kill_urb(urb);
 433                         usb_free_urb(urb);
 434                         kfree(cport_in->buffer[i]);
 435                         cport_in->buffer[i] = NULL;
 436                 }
 437         }
 438
 439         usb_set_intfdata(interface, NULL);
 440         udev = es1->usb_dev;
 441         greybus_remove_hd(es1->hd);
 442         kfree(es1->cport_to_ep);
 443
 444         usb_put_dev(udev);
 445 }
 446
 447 static void cport_in_callback(struct urb *urb)
 448 {
 449         struct greybus_host_device *hd = urb->context;
 450         struct device *dev = &urb->dev->dev;
 451         struct gb_operation_msg_hdr *header;
 452         int status = check_urb_status(urb);
 453         int retval;
 454         u16 cport_id;
 455
 456         if (status) {
 457                 if ((status == -EAGAIN) || (status == -EPROTO))
 458                         goto exit;
 459                 dev_err(dev, "urb cport in error %d (dropped)\n", status);
 460                 return;
 461         }
 462
 463         if (urb->actual_length < sizeof(*header)) {
 464                 dev_err(dev, "%s: short message received\n", __func__);
 465                 goto exit;
 466         }
 467
 468         /* Extract the CPort id, which is packed in the message header */
 469         header = urb->transfer_buffer;
 470         cport_id = gb_message_cport_unpack(header);
 471
 472         if (cport_id_valid(hd, cport_id))
 473                 greybus_data_rcvd(hd, cport_id, urb->transfer_buffer,
 474                                                         urb->actual_length);
 475         else
 476                 dev_err(dev, "%s: invalid cport id 0x%02x received\n",
 477                                 __func__, cport_id);
 478 exit:
 479         /* put our urb back in the request pool */
 480         retval = usb_submit_urb(urb, GFP_ATOMIC);
 481         if (retval)
 482                 dev_err(dev, "%s: error %d in submitting urb.\n",
 483                         __func__, retval);
 484 }
 485
 486 static void cport_out_callback(struct urb *urb)
 487 {
 488         struct gb_message *message = urb->context;
 489         struct greybus_host_device *hd = message->operation->connection->hd;
 490         struct es1_ap_dev *es1 = hd_to_es1(hd);
 491         int status = check_urb_status(urb);
 492         unsigned long flags;
 493
 494         gb_message_cport_clear(message->header);
 495
 496         /*
 497          * Tell the submitter that the message send (attempt) is
 498          * complete, and report the status.
 499          */
 500         greybus_message_sent(hd, message, status);
 501
 502         spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
 503         message->hcpriv = NULL;
 504         spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
 505
 506         free_urb(es1, urb);
 507 }
 508
 509 #define APB1_LOG_MSG_SIZE       64
 510 static void apb1_log_get(struct es1_ap_dev *es1, char *buf)
 511 {
 512         int retval;
 513
 514         /* SVC messages go down our control pipe */
 515         do {
 516                 retval = usb_control_msg(es1->usb_dev,
 517                                         usb_rcvctrlpipe(es1->usb_dev, 0),
 518                                         REQUEST_LOG,
 519                                         USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 520                                         0x00, 0x00,
 521                                         buf,
 522                                         APB1_LOG_MSG_SIZE,
 523                                         ES1_TIMEOUT);
 524                 if (retval > 0)
 525                         kfifo_in(&apb1_log_fifo, buf, retval);
 526         } while (retval > 0);
 527 }
 528
 529 static int apb1_log_poll(void *data)
 530 {
 531         struct es1_ap_dev *es1 = data;
 532         char *buf;
 533
 534         buf = kmalloc(APB1_LOG_MSG_SIZE, GFP_KERNEL);
 535         if (!buf)
 536                 return -ENOMEM;
 537
 538         while (!kthread_should_stop()) {
 539                 msleep(1000);
 540                 apb1_log_get(es1, buf);
 541         }
 542
 543         kfree(buf);
 544
 545         return 0;
 546 }
 547
 548 static ssize_t apb1_log_read(struct file *f, char __user *buf,
 549                                 size_t count, loff_t *ppos)
 550 {
 551         ssize_t ret;
 552         size_t copied;
 553         char *tmp_buf;
 554
 555         if (count > APB1_LOG_SIZE)
 556                 count = APB1_LOG_SIZE;
 557
 558         tmp_buf = kmalloc(count, GFP_KERNEL);
 559         if (!tmp_buf)
 560                 return -ENOMEM;
 561
 562         copied = kfifo_out(&apb1_log_fifo, tmp_buf, count);
 563         ret = simple_read_from_buffer(buf, count, ppos, tmp_buf, copied);
 564
 565         kfree(tmp_buf);
 566
 567         return ret;
 568 }
 569
 570 static const struct file_operations apb1_log_fops = {
 571         .read   = apb1_log_read,
 572 };
 573
 574 static void usb_log_enable(struct es1_ap_dev *es1)
 575 {
 576         if (!IS_ERR_OR_NULL(apb1_log_task))
 577                 return;
 578
 579         /* get log from APB1 */
 580         apb1_log_task = kthread_run(apb1_log_poll, es1, "apb1_log");
 581         if (IS_ERR(apb1_log_task))
 582                 return;
 583         apb1_log_dentry = debugfs_create_file("apb1_log", S_IRUGO,
 584                                                 gb_debugfs_get(), NULL,
 585                                                 &apb1_log_fops);
 586 }
 587
 588 static void usb_log_disable(struct es1_ap_dev *es1)
 589 {
 590         if (IS_ERR_OR_NULL(apb1_log_task))
 591                 return;
 592
 593         debugfs_remove(apb1_log_dentry);
 594         apb1_log_dentry = NULL;
 595
 596         kthread_stop(apb1_log_task);
 597         apb1_log_task = NULL;
 598 }
 599
 600 static ssize_t apb1_log_enable_read(struct file *f, char __user *buf,
 601                                 size_t count, loff_t *ppos)
 602 {
 603         char tmp_buf[3];
 604         int enable = !IS_ERR_OR_NULL(apb1_log_task);
 605
 606         sprintf(tmp_buf, "%d\n", enable);
 607         return simple_read_from_buffer(buf, count, ppos, tmp_buf, 3);
 608 }
 609
 610 static ssize_t apb1_log_enable_write(struct file *f, const char __user *buf,
 611                                 size_t count, loff_t *ppos)
 612 {
 613         int enable;
 614         ssize_t retval;
 615         struct es1_ap_dev *es1 = (struct es1_ap_dev *)f->f_inode->i_private;
 616
 617         retval = kstrtoint_from_user(buf, count, 10, &enable);
 618         if (retval)
 619                 return retval;
 620
 621         if (enable)
 622                 usb_log_enable(es1);
 623         else
 624                 usb_log_disable(es1);
 625
 626         return count;
 627 }
 628
 629 static const struct file_operations apb1_log_enable_fops = {
 630         .read   = apb1_log_enable_read,
 631         .write  = apb1_log_enable_write,
 632 };
 633
 634 static int apb1_get_cport_count(struct usb_device *udev)
 635 {
 636         int retval;
 637         __le16 *cport_count;
 638
 639         cport_count = kmalloc(sizeof(*cport_count), GFP_KERNEL);
 640         if (!cport_count)
 641                 return -ENOMEM;
 642
 643         retval = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 644                                  REQUEST_CPORT_COUNT,
 645                                  USB_DIR_IN | USB_TYPE_VENDOR |
 646                                  USB_RECIP_INTERFACE, 0, 0, cport_count,
 647                                  sizeof(*cport_count), ES1_TIMEOUT);
 648         if (retval < 0) {
 649                 dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
 650                         retval);
 651                 goto out;
 652         }
 653
 654         retval = le16_to_cpu(*cport_count);
 655
 656         /* We need to fit a CPort ID in one byte of a message header */
 657         if (retval > U8_MAX) {
 658                 retval = U8_MAX;
 659                 dev_warn(&udev->dev, "Limiting number of CPorts to U8_MAX\n");
 660         }
 661
 662 out:
 663         kfree(cport_count);
 664         return retval;
 665 }
 666
 667 /*
 668  * The ES1 USB Bridge device contains 4 endpoints
 669  * 1 Control - usual USB stuff + AP -> SVC messages
 670  * 1 Interrupt IN - SVC -> AP messages
 671  * 1 Bulk IN - CPort data in
 672  * 1 Bulk OUT - CPort data out
 673  */
 674 static int ap_probe(struct usb_interface *interface,
 675                     const struct usb_device_id *id)
 676 {
 677         struct es1_ap_dev *es1;
 678         struct greybus_host_device *hd;
 679         struct usb_device *udev;
 680         struct usb_host_interface *iface_desc;
 681         struct usb_endpoint_descriptor *endpoint;
 682         int bulk_in = 0;
 683         int bulk_out = 0;
 684         int retval = -ENOMEM;
 685         int i;
 686         int num_cports;
 687
 688         udev = usb_get_dev(interface_to_usbdev(interface));
 689
 690         num_cports = apb1_get_cport_count(udev);
 691         if (num_cports < 0) {
 692                 usb_put_dev(udev);
 693                 dev_err(&udev->dev, "Cannot retrieve CPort count: %d\n",
 694                         num_cports);
 695                 return num_cports;
 696         }
 697
 698         hd = greybus_create_hd(&es1_driver, &udev->dev, ES1_GBUF_MSG_SIZE_MAX,
 699                                num_cports);
 700         if (IS_ERR(hd)) {
 701                 usb_put_dev(udev);
 702                 return PTR_ERR(hd);
 703         }
 704
 705         es1 = hd_to_es1(hd);
 706         es1->hd = hd;
 707         es1->usb_intf = interface;
 708         es1->usb_dev = udev;
 709         spin_lock_init(&es1->cport_out_urb_lock);
 710         usb_set_intfdata(interface, es1);
 711
 712         es1->cport_to_ep = kcalloc(hd->num_cports, sizeof(*es1->cport_to_ep),
 713                                    GFP_KERNEL);
 714         if (!es1->cport_to_ep) {
 715                 retval = -ENOMEM;
 716                 goto error;
 717         }
 718
 719         /* find all 3 of our endpoints */
 720         iface_desc = interface->cur_altsetting;
 721         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 722                 endpoint = &iface_desc->endpoint[i].desc;
 723
 724                 if (usb_endpoint_is_bulk_in(endpoint)) {
 725                         es1->cport_in[bulk_in++].endpoint =
 726                                 endpoint->bEndpointAddress;
 727                 } else if (usb_endpoint_is_bulk_out(endpoint)) {
 728                         es1->cport_out[bulk_out++].endpoint =
 729                                 endpoint->bEndpointAddress;
 730                 } else {
 731                         dev_err(&udev->dev,
 732                                 "Unknown endpoint type found, address %x\n",
 733                                 endpoint->bEndpointAddress);
 734                 }
 735         }
 736         if ((bulk_in == 0) ||
 737             (bulk_out == 0)) {
 738                 dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n");
 739                 goto error;
 740         }
 741
 742         /* Allocate buffers for our cport in messages and start them up */
 743         for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
 744                 struct es1_cport_in *cport_in = &es1->cport_in[bulk_in];
 745                 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
 746                         struct urb *urb;
 747                         u8 *buffer;
 748
 749                         urb = usb_alloc_urb(0, GFP_KERNEL);
 750                         if (!urb)
 751                                 goto error;
 752                         buffer = kmalloc(ES1_GBUF_MSG_SIZE_MAX, GFP_KERNEL);
 753                         if (!buffer)
 754                                 goto error;
 755
 756                         usb_fill_bulk_urb(urb, udev,
 757                                           usb_rcvbulkpipe(udev,
 758                                                           cport_in->endpoint),
 759                                           buffer, ES1_GBUF_MSG_SIZE_MAX,
 760                                           cport_in_callback, hd);
 761                         cport_in->urb[i] = urb;
 762                         cport_in->buffer[i] = buffer;
 763                         retval = usb_submit_urb(urb, GFP_KERNEL);
 764                         if (retval)
 765                                 goto error;
 766                 }
 767         }
 768
 769         /* Allocate urbs for our CPort OUT messages */
 770         for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
 771                 struct urb *urb;
 772
 773                 urb = usb_alloc_urb(0, GFP_KERNEL);
 774                 if (!urb)
 775                         goto error;
 776
 777                 es1->cport_out_urb[i] = urb;
 778                 es1->cport_out_urb_busy[i] = false;     /* just to be anal */
 779         }
 780
 781         apb1_log_enable_dentry = debugfs_create_file("apb1_log_enable",
 782                                                         (S_IWUSR | S_IRUGO),
 783                                                         gb_debugfs_get(), es1,
 784                                                         &apb1_log_enable_fops);
 785         return 0;
 786 error:
 787         ap_disconnect(interface);
 788
 789         return retval;
 790 }
 791
 792 static struct usb_driver es1_ap_driver = {
 793         .name =         "es2_ap_driver",
 794         .probe =        ap_probe,
 795         .disconnect =   ap_disconnect,
 796         .id_table =     id_table,
 797 };
 798
 799 module_usb_driver(es1_ap_driver);
 800
 801 MODULE_LICENSE("GPL v2");
 802 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");