kernel/drivers/staging/most/hdm-usb/hdm_usb.c

   1 /*
   2  * hdm_usb.c - Hardware dependent module for USB
   3  *
   4  * Copyright (C) 2013-2015 Microchip Technology Germany II GmbH & Co. KG
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * This file is licensed under GPLv2.
  12  */
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15 #include <linux/module.h>
  16 #include <linux/fs.h>
  17 #include <linux/usb.h>
  18 #include <linux/slab.h>
  19 #include <linux/init.h>
  20 #include <linux/cdev.h>
  21 #include <linux/device.h>
  22 #include <linux/list.h>
  23 #include <linux/completion.h>
  24 #include <linux/mutex.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/workqueue.h>
  28 #include <linux/sysfs.h>
  29 #include <linux/dma-mapping.h>
  30 #include <linux/etherdevice.h>
  31 #include <linux/uaccess.h>
  32 #include "mostcore.h"
  33 #include "networking.h"
  34
  35 #define USB_MTU                 512
  36 #define NO_ISOCHRONOUS_URB      0
  37 #define AV_PACKETS_PER_XACT     2
  38 #define BUF_CHAIN_SIZE          0xFFFF
  39 #define MAX_NUM_ENDPOINTS       30
  40 #define MAX_SUFFIX_LEN          10
  41 #define MAX_STRING_LEN          80
  42 #define MAX_BUF_SIZE            0xFFFF
  43 #define CEILING(x, y)           (((x) + (y) - 1) / (y))
  44
  45 #define USB_VENDOR_ID_SMSC      0x0424  /* VID: SMSC */
  46 #define USB_DEV_ID_BRDG         0xC001  /* PID: USB Bridge */
  47 #define USB_DEV_ID_INIC         0xCF18  /* PID: USB INIC */
  48 #define HW_RESYNC               0x0000
  49 /* DRCI Addresses */
  50 #define DRCI_REG_NI_STATE       0x0100
  51 #define DRCI_REG_PACKET_BW      0x0101
  52 #define DRCI_REG_NODE_ADDR      0x0102
  53 #define DRCI_REG_NODE_POS       0x0103
  54 #define DRCI_REG_MEP_FILTER     0x0140
  55 #define DRCI_REG_HASH_TBL0      0x0141
  56 #define DRCI_REG_HASH_TBL1      0x0142
  57 #define DRCI_REG_HASH_TBL2      0x0143
  58 #define DRCI_REG_HASH_TBL3      0x0144
  59 #define DRCI_REG_HW_ADDR_HI     0x0145
  60 #define DRCI_REG_HW_ADDR_MI     0x0146
  61 #define DRCI_REG_HW_ADDR_LO     0x0147
  62 #define DRCI_REG_BASE           0x1100
  63 #define DRCI_COMMAND            0x02
  64 #define DRCI_READ_REQ           0xA0
  65 #define DRCI_WRITE_REQ          0xA1
  66
  67 /**
  68  * struct buf_anchor - used to create a list of pending URBs
  69  * @urb: pointer to USB request block
  70  * @clear_work_obj:
  71  * @list: linked list
  72  * @urb_completion:
  73  */
  74 struct buf_anchor {
  75         struct urb *urb;
  76         struct work_struct clear_work_obj;
  77         struct list_head list;
  78         struct completion urb_compl;
  79 };
  80
  81 #define to_buf_anchor(w) container_of(w, struct buf_anchor, clear_work_obj)
  82
  83 /**
  84  * struct most_dci_obj - Direct Communication Interface
  85  * @kobj:position in sysfs
  86  * @usb_device: pointer to the usb device
  87  */
  88 struct most_dci_obj {
  89         struct kobject kobj;
  90         struct usb_device *usb_device;
  91 };
  92
  93 #define to_dci_obj(p) container_of(p, struct most_dci_obj, kobj)
  94
  95 /**
  96  * struct most_dev - holds all usb interface specific stuff
  97  * @parent: parent object in sysfs
  98  * @usb_device: pointer to usb device
  99  * @iface: hardware interface
 100  * @cap: channel capabilities
 101  * @conf: channel configuration
 102  * @dci: direct communication interface of hardware
 103  * @hw_addr: MAC address of hardware
 104  * @ep_address: endpoint address table
 105  * @link_stat: link status of hardware
 106  * @description: device description
 107  * @suffix: suffix for channel name
 108  * @anchor_list_lock: locks list access
 109  * @padding_active: indicates channel uses padding
 110  * @is_channel_healthy: health status table of each channel
 111  * @anchor_list: list of anchored items
 112  * @io_mutex: synchronize I/O with disconnect
 113  * @link_stat_timer: timer for link status reports
 114  * @poll_work_obj: work for polling link status
 115  */
 116 struct most_dev {
 117         struct kobject *parent;
 118         struct usb_device *usb_device;
 119         struct most_interface iface;
 120         struct most_channel_capability *cap;
 121         struct most_channel_config *conf;
 122         struct most_dci_obj *dci;
 123         u8 hw_addr[6];
 124         u8 *ep_address;
 125         u16 link_stat;
 126         char description[MAX_STRING_LEN];
 127         char suffix[MAX_NUM_ENDPOINTS][MAX_SUFFIX_LEN];
 128         spinlock_t anchor_list_lock[MAX_NUM_ENDPOINTS];
 129         bool padding_active[MAX_NUM_ENDPOINTS];
 130         bool is_channel_healthy[MAX_NUM_ENDPOINTS];
 131         struct list_head *anchor_list;
 132         struct mutex io_mutex;
 133         struct timer_list link_stat_timer;
 134         struct work_struct poll_work_obj;
 135 };
 136
 137 #define to_mdev(d) container_of(d, struct most_dev, iface)
 138 #define to_mdev_from_work(w) container_of(w, struct most_dev, poll_work_obj)
 139
 140 static struct workqueue_struct *schedule_usb_work;
 141 static void wq_clear_halt(struct work_struct *wq_obj);
 142 static void wq_netinfo(struct work_struct *wq_obj);
 143
 144 /**
 145  * drci_rd_reg - read a DCI register
 146  * @dev: usb device
 147  * @reg: register address
 148  * @buf: buffer to store data
 149  *
 150  * This is reads data from INIC's direct register communication interface
 151  */
 152 static inline int drci_rd_reg(struct usb_device *dev, u16 reg, u16 *buf)
 153 {
 154         int retval;
 155         u16 *dma_buf = kzalloc(sizeof(u16), GFP_KERNEL);
 156         u8 req_type = USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE;
 157
 158         if (!dma_buf)
 159                 return -ENOMEM;
 160
 161         retval = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 162                                  DRCI_READ_REQ, req_type,
 163                                  0x0000,
 164                                  reg, dma_buf, sizeof(u16), 5 * HZ);
 165         *buf = le16_to_cpu(*dma_buf);
 166         kfree(dma_buf);
 167
 168         return retval;
 169 }
 170
 171 /**
 172  * drci_wr_reg - write a DCI register
 173  * @dev: usb device
 174  * @reg: register address
 175  * @data: data to write
 176  *
 177  * This is writes data to INIC's direct register communication interface
 178  */
 179 static inline int drci_wr_reg(struct usb_device *dev, u16 reg, u16 data)
 180 {
 181         return usb_control_msg(dev,
 182                                usb_sndctrlpipe(dev, 0),
 183                                DRCI_WRITE_REQ,
 184                                USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 185                                data,
 186                                reg,
 187                                NULL,
 188                                0,
 189                                5 * HZ);
 190 }
 191
 192 /**
 193  * free_anchored_buffers - free device's anchored items
 194  * @mdev: the device
 195  * @channel: channel ID
 196  */
 197 static void free_anchored_buffers(struct most_dev *mdev, unsigned int channel)
 198 {
 199         struct mbo *mbo;
 200         struct buf_anchor *anchor, *tmp;
 201         unsigned long flags;
 202
 203         spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 204         list_for_each_entry_safe(anchor, tmp, &mdev->anchor_list[channel],
 205                                  list) {
 206                 struct urb *urb = anchor->urb;
 207
 208                 spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 209                 if (likely(urb)) {
 210                         mbo = urb->context;
 211                         if (!irqs_disabled()) {
 212                                 usb_kill_urb(urb);
 213                         } else {
 214                                 usb_unlink_urb(urb);
 215                                 wait_for_completion(&anchor->urb_compl);
 216                         }
 217                         if ((mbo) && (mbo->complete)) {
 218                                 mbo->status = MBO_E_CLOSE;
 219                                 mbo->processed_length = 0;
 220                                 mbo->complete(mbo);
 221                         }
 222                         usb_free_urb(urb);
 223                 }
 224                 spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 225                 list_del(&anchor->list);
 226                 kfree(anchor);
 227         }
 228         spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 229 }
 230
 231 /**
 232  * get_stream_frame_size - calculate frame size of current configuration
 233  * @cfg: channel configuration
 234  */
 235 static unsigned int get_stream_frame_size(struct most_channel_config *cfg)
 236 {
 237         unsigned int frame_size = 0;
 238         unsigned int sub_size = cfg->subbuffer_size;
 239
 240         if (!sub_size) {
 241                 pr_warn("Misconfig: Subbuffer size zero.\n");
 242                 return frame_size;
 243         }
 244         switch (cfg->data_type) {
 245         case MOST_CH_ISOC_AVP:
 246                 frame_size = AV_PACKETS_PER_XACT * sub_size;
 247                 break;
 248         case MOST_CH_SYNC:
 249                 if (cfg->packets_per_xact == 0) {
 250                         pr_warn("Misconfig: Packets per XACT zero\n");
 251                         frame_size = 0;
 252                 } else if (cfg->packets_per_xact == 0xFF) {
 253                         frame_size = (USB_MTU / sub_size) * sub_size;
 254                 } else {
 255                         frame_size = cfg->packets_per_xact * sub_size;
 256                 }
 257                 break;
 258         default:
 259                 pr_warn("Query frame size of non-streaming channel\n");
 260                 break;
 261         }
 262         return frame_size;
 263 }
 264
 265 /**
 266  * hdm_poison_channel - mark buffers of this channel as invalid
 267  * @iface: pointer to the interface
 268  * @channel: channel ID
 269  *
 270  * This unlinks all URBs submitted to the HCD,
 271  * calls the associated completion function of the core and removes
 272  * them from the list.
 273  *
 274  * Returns 0 on success or error code otherwise.
 275  */
 276 static int hdm_poison_channel(struct most_interface *iface, int channel)
 277 {
 278         struct most_dev *mdev;
 279
 280         mdev = to_mdev(iface);
 281         if (unlikely(!iface)) {
 282                 dev_warn(&mdev->usb_device->dev, "Poison: Bad interface.\n");
 283                 return -EIO;
 284         }
 285         if (unlikely((channel < 0) || (channel >= iface->num_channels))) {
 286                 dev_warn(&mdev->usb_device->dev, "Channel ID out of range.\n");
 287                 return -ECHRNG;
 288         }
 289
 290         mdev->is_channel_healthy[channel] = false;
 291
 292         mutex_lock(&mdev->io_mutex);
 293         free_anchored_buffers(mdev, channel);
 294         if (mdev->padding_active[channel])
 295                 mdev->padding_active[channel] = false;
 296
 297         if (mdev->conf[channel].data_type == MOST_CH_ASYNC) {
 298                 del_timer_sync(&mdev->link_stat_timer);
 299                 cancel_work_sync(&mdev->poll_work_obj);
 300         }
 301         mutex_unlock(&mdev->io_mutex);
 302         return 0;
 303 }
 304
 305 /**
 306  * hdm_add_padding - add padding bytes
 307  * @mdev: most device
 308  * @channel: channel ID
 309  * @mbo: buffer object
 310  *
 311  * This inserts the INIC hardware specific padding bytes into a streaming
 312  * channel's buffer
 313  */
 314 static int hdm_add_padding(struct most_dev *mdev, int channel, struct mbo *mbo)
 315 {
 316         struct most_channel_config *conf = &mdev->conf[channel];
 317         unsigned int j, num_frames, frame_size;
 318         u16 rd_addr, wr_addr;
 319
 320         frame_size = get_stream_frame_size(conf);
 321         if (!frame_size)
 322                 return -EIO;
 323         num_frames = mbo->buffer_length / frame_size;
 324
 325         if (num_frames < 1) {
 326                 dev_err(&mdev->usb_device->dev,
 327                         "Missed minimal transfer unit.\n");
 328                 return -EIO;
 329         }
 330
 331         for (j = 1; j < num_frames; j++) {
 332                 wr_addr = (num_frames - j) * USB_MTU;
 333                 rd_addr = (num_frames - j) * frame_size;
 334                 memmove(mbo->virt_address + wr_addr,
 335                         mbo->virt_address + rd_addr,
 336                         frame_size);
 337         }
 338         mbo->buffer_length = num_frames * USB_MTU;
 339         return 0;
 340 }
 341
 342 /**
 343  * hdm_remove_padding - remove padding bytes
 344  * @mdev: most device
 345  * @channel: channel ID
 346  * @mbo: buffer object
 347  *
 348  * This takes the INIC hardware specific padding bytes off a streaming
 349  * channel's buffer.
 350  */
 351 static int hdm_remove_padding(struct most_dev *mdev, int channel,
 352                               struct mbo *mbo)
 353 {
 354         unsigned int j, num_frames, frame_size;
 355         struct most_channel_config *const conf = &mdev->conf[channel];
 356
 357         frame_size = get_stream_frame_size(conf);
 358         if (!frame_size)
 359                 return -EIO;
 360         num_frames = mbo->processed_length / USB_MTU;
 361
 362         for (j = 1; j < num_frames; j++)
 363                 memmove(mbo->virt_address + frame_size * j,
 364                         mbo->virt_address + USB_MTU * j,
 365                         frame_size);
 366
 367         mbo->processed_length = frame_size * num_frames;
 368         return 0;
 369 }
 370
 371 /**
 372  * hdm_write_completion - completion function for submitted Tx URBs
 373  * @urb: the URB that has been completed
 374  *
 375  * This checks the status of the completed URB. In case the URB has been
 376  * unlinked before, it is immediately freed. On any other error the MBO
 377  * transfer flag is set. On success it frees allocated resources and calls
 378  * the completion function.
 379  *
 380  * Context: interrupt!
 381  */
 382 static void hdm_write_completion(struct urb *urb)
 383 {
 384         struct mbo *mbo;
 385         struct buf_anchor *anchor;
 386         struct most_dev *mdev;
 387         struct device *dev;
 388         unsigned int channel;
 389         unsigned long flags;
 390
 391         mbo = urb->context;
 392         anchor = mbo->priv;
 393         mdev = to_mdev(mbo->ifp);
 394         channel = mbo->hdm_channel_id;
 395         dev = &mdev->usb_device->dev;
 396
 397         if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 398             (!mdev->is_channel_healthy[channel])) {
 399                 complete(&anchor->urb_compl);
 400                 return;
 401         }
 402
 403         if (unlikely(urb->status && !(urb->status == -ENOENT ||
 404                                       urb->status == -ECONNRESET ||
 405                                       urb->status == -ESHUTDOWN))) {
 406                 mbo->processed_length = 0;
 407                 switch (urb->status) {
 408                 case -EPIPE:
 409                         dev_warn(dev, "Broken OUT pipe detected\n");
 410                         most_stop_enqueue(&mdev->iface, channel);
 411                         mbo->status = MBO_E_INVAL;
 412                         usb_unlink_urb(urb);
 413                         INIT_WORK(&anchor->clear_work_obj, wq_clear_halt);
 414                         queue_work(schedule_usb_work, &anchor->clear_work_obj);
 415                         return;
 416                 case -ENODEV:
 417                 case -EPROTO:
 418                         mbo->status = MBO_E_CLOSE;
 419                         break;
 420                 default:
 421                         mbo->status = MBO_E_INVAL;
 422                         break;
 423                 }
 424         } else {
 425                 mbo->status = MBO_SUCCESS;
 426                 mbo->processed_length = urb->actual_length;
 427         }
 428
 429         spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 430         list_del(&anchor->list);
 431         spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 432         kfree(anchor);
 433
 434         if (likely(mbo->complete))
 435                 mbo->complete(mbo);
 436         usb_free_urb(urb);
 437 }
 438
 439 /**
 440  * hdm_read_completion - completion function for submitted Rx URBs
 441  * @urb: the URB that has been completed
 442  *
 443  * This checks the status of the completed URB. In case the URB has been
 444  * unlinked before it is immediately freed. On any other error the MBO transfer
 445  * flag is set. On success it frees allocated resources, removes
 446  * padding bytes -if necessary- and calls the completion function.
 447  *
 448  * Context: interrupt!
 449  *
 450  * **************************************************************************
 451  *                   Error codes returned by in urb->status
 452  *                   or in iso_frame_desc[n].status (for ISO)
 453  * *************************************************************************
 454  *
 455  * USB device drivers may only test urb status values in completion handlers.
 456  * This is because otherwise there would be a race between HCDs updating
 457  * these values on one CPU, and device drivers testing them on another CPU.
 458  *
 459  * A transfer's actual_length may be positive even when an error has been
 460  * reported.  That's because transfers often involve several packets, so that
 461  * one or more packets could finish before an error stops further endpoint I/O.
 462  *
 463  * For isochronous URBs, the urb status value is non-zero only if the URB is
 464  * unlinked, the device is removed, the host controller is disabled or the total
 465  * transferred length is less than the requested length and the URB_SHORT_NOT_OK
 466  * flag is set.  Completion handlers for isochronous URBs should only see
 467  * urb->status set to zero, -ENOENT, -ECONNRESET, -ESHUTDOWN, or -EREMOTEIO.
 468  * Individual frame descriptor status fields may report more status codes.
 469  *
 470  *
 471  * 0                    Transfer completed successfully
 472  *
 473  * -ENOENT              URB was synchronously unlinked by usb_unlink_urb
 474  *
 475  * -EINPROGRESS         URB still pending, no results yet
 476  *                      (That is, if drivers see this it's a bug.)
 477  *
 478  * -EPROTO (*, **)      a) bitstuff error
 479  *                      b) no response packet received within the
 480  *                         prescribed bus turn-around time
 481  *                      c) unknown USB error
 482  *
 483  * -EILSEQ (*, **)      a) CRC mismatch
 484  *                      b) no response packet received within the
 485  *                         prescribed bus turn-around time
 486  *                      c) unknown USB error
 487  *
 488  *                      Note that often the controller hardware does not
 489  *                      distinguish among cases a), b), and c), so a
 490  *                      driver cannot tell whether there was a protocol
 491  *                      error, a failure to respond (often caused by
 492  *                      device disconnect), or some other fault.
 493  *
 494  * -ETIME (**)          No response packet received within the prescribed
 495  *                      bus turn-around time.  This error may instead be
 496  *                      reported as -EPROTO or -EILSEQ.
 497  *
 498  * -ETIMEDOUT           Synchronous USB message functions use this code
 499  *                      to indicate timeout expired before the transfer
 500  *                      completed, and no other error was reported by HC.
 501  *
 502  * -EPIPE (**)          Endpoint stalled.  For non-control endpoints,
 503  *                      reset this status with usb_clear_halt().
 504  *
 505  * -ECOMM               During an IN transfer, the host controller
 506  *                      received data from an endpoint faster than it
 507  *                      could be written to system memory
 508  *
 509  * -ENOSR               During an OUT transfer, the host controller
 510  *                      could not retrieve data from system memory fast
 511  *                      enough to keep up with the USB data rate
 512  *
 513  * -EOVERFLOW (*)       The amount of data returned by the endpoint was
 514  *                      greater than either the max packet size of the
 515  *                      endpoint or the remaining buffer size.  "Babble".
 516  *
 517  * -EREMOTEIO           The data read from the endpoint did not fill the
 518  *                      specified buffer, and URB_SHORT_NOT_OK was set in
 519  *                      urb->transfer_flags.
 520  *
 521  * -ENODEV              Device was removed.  Often preceded by a burst of
 522  *                      other errors, since the hub driver doesn't detect
 523  *                      device removal events immediately.
 524  *
 525  * -EXDEV               ISO transfer only partially completed
 526  *                      (only set in iso_frame_desc[n].status, not urb->status)
 527  *
 528  * -EINVAL              ISO madness, if this happens: Log off and go home
 529  *
 530  * -ECONNRESET          URB was asynchronously unlinked by usb_unlink_urb
 531  *
 532  * -ESHUTDOWN           The device or host controller has been disabled due
 533  *                      to some problem that could not be worked around,
 534  *                      such as a physical disconnect.
 535  *
 536  *
 537  * (*) Error codes like -EPROTO, -EILSEQ and -EOVERFLOW normally indicate
 538  * hardware problems such as bad devices (including firmware) or cables.
 539  *
 540  * (**) This is also one of several codes that different kinds of host
 541  * controller use to indicate a transfer has failed because of device
 542  * disconnect.  In the interval before the hub driver starts disconnect
 543  * processing, devices may receive such fault reports for every request.
 544  *
 545  * See <https://www.kernel.org/doc/Documentation/usb/error-codes.txt>
 546  */
 547 static void hdm_read_completion(struct urb *urb)
 548 {
 549         struct mbo *mbo;
 550         struct buf_anchor *anchor;
 551         struct most_dev *mdev;
 552         struct device *dev;
 553         unsigned long flags;
 554         unsigned int channel;
 555
 556         mbo = urb->context;
 557         anchor = mbo->priv;
 558         mdev = to_mdev(mbo->ifp);
 559         channel = mbo->hdm_channel_id;
 560         dev = &mdev->usb_device->dev;
 561
 562         if ((urb->status == -ENOENT) || (urb->status == -ECONNRESET) ||
 563             (!mdev->is_channel_healthy[channel])) {
 564                 complete(&anchor->urb_compl);
 565                 return;
 566         }
 567
 568         if (unlikely(urb->status && !(urb->status == -ENOENT ||
 569                                       urb->status == -ECONNRESET ||
 570                                       urb->status == -ESHUTDOWN))) {
 571                 mbo->processed_length = 0;
 572                 switch (urb->status) {
 573                 case -EPIPE:
 574                         dev_warn(dev, "Broken IN pipe detected\n");
 575                         mbo->status = MBO_E_INVAL;
 576                         usb_unlink_urb(urb);
 577                         INIT_WORK(&anchor->clear_work_obj, wq_clear_halt);
 578                         queue_work(schedule_usb_work, &anchor->clear_work_obj);
 579                         return;
 580                 case -ENODEV:
 581                 case -EPROTO:
 582                         mbo->status = MBO_E_CLOSE;
 583                         break;
 584                 case -EOVERFLOW:
 585                         dev_warn(dev, "Babble on IN pipe detected\n");
 586                 default:
 587                         mbo->status = MBO_E_INVAL;
 588                         break;
 589                 }
 590         } else {
 591                 mbo->processed_length = urb->actual_length;
 592                 if (!mdev->padding_active[channel]) {
 593                         mbo->status = MBO_SUCCESS;
 594                 } else {
 595                         if (hdm_remove_padding(mdev, channel, mbo)) {
 596                                 mbo->processed_length = 0;
 597                                 mbo->status = MBO_E_INVAL;
 598                         } else {
 599                                 mbo->status = MBO_SUCCESS;
 600                         }
 601                 }
 602         }
 603         spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 604         list_del(&anchor->list);
 605         spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 606         kfree(anchor);
 607
 608         if (likely(mbo->complete))
 609                 mbo->complete(mbo);
 610         usb_free_urb(urb);
 611 }
 612
 613 /**
 614  * hdm_enqueue - receive a buffer to be used for data transfer
 615  * @iface: interface to enqueue to
 616  * @channel: ID of the channel
 617  * @mbo: pointer to the buffer object
 618  *
 619  * This allocates a new URB and fills it according to the channel
 620  * that is being used for transmission of data. Before the URB is
 621  * submitted it is stored in the private anchor list.
 622  *
 623  * Returns 0 on success. On any error the URB is freed and a error code
 624  * is returned.
 625  *
 626  * Context: Could in _some_ cases be interrupt!
 627  */
 628 static int hdm_enqueue(struct most_interface *iface, int channel,
 629                        struct mbo *mbo)
 630 {
 631         struct most_dev *mdev;
 632         struct buf_anchor *anchor;
 633         struct most_channel_config *conf;
 634         struct device *dev;
 635         int retval = 0;
 636         struct urb *urb;
 637         unsigned long flags;
 638         unsigned long length;
 639         void *virt_address;
 640
 641         if (unlikely(!iface || !mbo))
 642                 return -EIO;
 643         if (unlikely(iface->num_channels <= channel) || (channel < 0))
 644                 return -ECHRNG;
 645
 646         mdev = to_mdev(iface);
 647         conf = &mdev->conf[channel];
 648         dev = &mdev->usb_device->dev;
 649
 650         if (!mdev->usb_device)
 651                 return -ENODEV;
 652
 653         urb = usb_alloc_urb(NO_ISOCHRONOUS_URB, GFP_ATOMIC);
 654         if (!urb) {
 655                 dev_err(dev, "Failed to allocate URB\n");
 656                 return -ENOMEM;
 657         }
 658
 659         anchor = kzalloc(sizeof(*anchor), GFP_ATOMIC);
 660         if (!anchor) {
 661                 retval = -ENOMEM;
 662                 goto _error;
 663         }
 664
 665         anchor->urb = urb;
 666         init_completion(&anchor->urb_compl);
 667         mbo->priv = anchor;
 668
 669         spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 670         list_add_tail(&anchor->list, &mdev->anchor_list[channel]);
 671         spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 672
 673         if ((mdev->padding_active[channel]) &&
 674             (conf->direction & MOST_CH_TX))
 675                 if (hdm_add_padding(mdev, channel, mbo)) {
 676                         retval = -EIO;
 677                         goto _error_1;
 678                 }
 679
 680         urb->transfer_dma = mbo->bus_address;
 681         virt_address = mbo->virt_address;
 682         length = mbo->buffer_length;
 683
 684         if (conf->direction & MOST_CH_TX) {
 685                 usb_fill_bulk_urb(urb, mdev->usb_device,
 686                                   usb_sndbulkpipe(mdev->usb_device,
 687                                                   mdev->ep_address[channel]),
 688                                   virt_address,
 689                                   length,
 690                                   hdm_write_completion,
 691                                   mbo);
 692                 if (conf->data_type != MOST_CH_ISOC_AVP)
 693                         urb->transfer_flags |= URB_ZERO_PACKET;
 694         } else {
 695                 usb_fill_bulk_urb(urb, mdev->usb_device,
 696                                   usb_rcvbulkpipe(mdev->usb_device,
 697                                                   mdev->ep_address[channel]),
 698                                   virt_address,
 699                                   length + conf->extra_len,
 700                                   hdm_read_completion,
 701                                   mbo);
 702         }
 703         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 704
 705         retval = usb_submit_urb(urb, GFP_KERNEL);
 706         if (retval) {
 707                 dev_err(dev, "URB submit failed with error %d.\n", retval);
 708                 goto _error_1;
 709         }
 710         return 0;
 711
 712 _error_1:
 713         spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 714         list_del(&anchor->list);
 715         spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 716         kfree(anchor);
 717 _error:
 718         usb_free_urb(urb);
 719         return retval;
 720 }
 721
 722 /**
 723  * hdm_configure_channel - receive channel configuration from core
 724  * @iface: interface
 725  * @channel: channel ID
 726  * @conf: structure that holds the configuration information
 727  */
 728 static int hdm_configure_channel(struct most_interface *iface, int channel,
 729                                  struct most_channel_config *conf)
 730 {
 731         unsigned int num_frames;
 732         unsigned int frame_size;
 733         unsigned int temp_size;
 734         unsigned int tail_space;
 735         struct most_dev *mdev;
 736         struct device *dev;
 737
 738         mdev = to_mdev(iface);
 739         mdev->is_channel_healthy[channel] = true;
 740         dev = &mdev->usb_device->dev;
 741
 742         if (unlikely(!iface || !conf)) {
 743                 dev_err(dev, "Bad interface or config pointer.\n");
 744                 return -EINVAL;
 745         }
 746         if (unlikely((channel < 0) || (channel >= iface->num_channels))) {
 747                 dev_err(dev, "Channel ID out of range.\n");
 748                 return -EINVAL;
 749         }
 750         if ((!conf->num_buffers) || (!conf->buffer_size)) {
 751                 dev_err(dev, "Misconfig: buffer size or #buffers zero.\n");
 752                 return -EINVAL;
 753         }
 754
 755         if (!(conf->data_type == MOST_CH_SYNC) &&
 756             !((conf->data_type == MOST_CH_ISOC_AVP) &&
 757               (conf->packets_per_xact != 0xFF))) {
 758                 mdev->padding_active[channel] = false;
 759                 goto exit;
 760         }
 761
 762         mdev->padding_active[channel] = true;
 763         temp_size = conf->buffer_size;
 764
 765         frame_size = get_stream_frame_size(conf);
 766         if ((frame_size == 0) || (frame_size > USB_MTU)) {
 767                 dev_warn(dev, "Misconfig: frame size wrong\n");
 768                 return -EINVAL;
 769         }
 770
 771         if (conf->buffer_size % frame_size) {
 772                 u16 tmp_val;
 773
 774                 tmp_val = conf->buffer_size / frame_size;
 775                 conf->buffer_size = tmp_val * frame_size;
 776                 dev_notice(dev,
 777                            "Channel %d - rounding buffer size to %d bytes, channel config says %d bytes\n",
 778                            channel,
 779                            conf->buffer_size,
 780                            temp_size);
 781         }
 782
 783         num_frames = conf->buffer_size / frame_size;
 784         tail_space = num_frames * (USB_MTU - frame_size);
 785         temp_size += tail_space;
 786
 787         /* calculate extra length to comply w/ HW padding */
 788         conf->extra_len = (CEILING(temp_size, USB_MTU) * USB_MTU)
 789                           - conf->buffer_size;
 790 exit:
 791         mdev->conf[channel] = *conf;
 792         return 0;
 793 }
 794
 795 /**
 796  * hdm_update_netinfo - retrieve latest networking information
 797  * @mdev: device interface
 798  *
 799  * This triggers the USB vendor requests to read the hardware address and
 800  * the current link status of the attached device.
 801  */
 802 static int hdm_update_netinfo(struct most_dev *mdev)
 803 {
 804         struct usb_device *usb_device = mdev->usb_device;
 805         struct device *dev = &usb_device->dev;
 806         u16 hi, mi, lo, link;
 807
 808         if (!is_valid_ether_addr(mdev->hw_addr)) {
 809                 if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_HI, &hi) < 0) {
 810                         dev_err(dev, "Vendor request \"hw_addr_hi\" failed\n");
 811                         return -1;
 812                 }
 813
 814                 if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_MI, &mi) < 0) {
 815                         dev_err(dev, "Vendor request \"hw_addr_mid\" failed\n");
 816                         return -1;
 817                 }
 818
 819                 if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_LO, &lo) < 0) {
 820                         dev_err(dev, "Vendor request \"hw_addr_low\" failed\n");
 821                         return -1;
 822                 }
 823
 824                 mutex_lock(&mdev->io_mutex);
 825                 mdev->hw_addr[0] = hi >> 8;
 826                 mdev->hw_addr[1] = hi;
 827                 mdev->hw_addr[2] = mi >> 8;
 828                 mdev->hw_addr[3] = mi;
 829                 mdev->hw_addr[4] = lo >> 8;
 830                 mdev->hw_addr[5] = lo;
 831                 mutex_unlock(&mdev->io_mutex);
 832         }
 833
 834         if (drci_rd_reg(usb_device, DRCI_REG_NI_STATE, &link) < 0) {
 835                 dev_err(dev, "Vendor request \"link status\" failed\n");
 836                 return -1;
 837         }
 838
 839         mutex_lock(&mdev->io_mutex);
 840         mdev->link_stat = link;
 841         mutex_unlock(&mdev->io_mutex);
 842         return 0;
 843 }
 844
 845 /**
 846  * hdm_request_netinfo - request network information
 847  * @iface: pointer to interface
 848  * @channel: channel ID
 849  *
 850  * This is used as trigger to set up the link status timer that
 851  * polls for the NI state of the INIC every 2 seconds.
 852  *
 853  */
 854 static void hdm_request_netinfo(struct most_interface *iface, int channel)
 855 {
 856         struct most_dev *mdev;
 857
 858         BUG_ON(!iface);
 859         mdev = to_mdev(iface);
 860         mdev->link_stat_timer.expires = jiffies + HZ;
 861         mod_timer(&mdev->link_stat_timer, mdev->link_stat_timer.expires);
 862 }
 863
 864 /**
 865  * link_stat_timer_handler - add work to link_stat work queue
 866  * @data: pointer to USB device instance
 867  *
 868  * The handler runs in interrupt context. That's why we need to defer the
 869  * tasks to a work queue.
 870  */
 871 static void link_stat_timer_handler(unsigned long data)
 872 {
 873         struct most_dev *mdev = (struct most_dev *)data;
 874
 875         queue_work(schedule_usb_work, &mdev->poll_work_obj);
 876         mdev->link_stat_timer.expires = jiffies + (2 * HZ);
 877         add_timer(&mdev->link_stat_timer);
 878 }
 879
 880 /**
 881  * wq_netinfo - work queue function
 882  * @wq_obj: object that holds data for our deferred work to do
 883  *
 884  * This retrieves the network interface status of the USB INIC
 885  * and compares it with the current status. If the status has
 886  * changed, it updates the status of the core.
 887  */
 888 static void wq_netinfo(struct work_struct *wq_obj)
 889 {
 890         struct most_dev *mdev;
 891         int i, prev_link_stat;
 892         u8 prev_hw_addr[6];
 893
 894         mdev = to_mdev_from_work(wq_obj);
 895         prev_link_stat = mdev->link_stat;
 896
 897         for (i = 0; i < 6; i++)
 898                 prev_hw_addr[i] = mdev->hw_addr[i];
 899
 900         if (hdm_update_netinfo(mdev) < 0)
 901                 return;
 902         if ((prev_link_stat != mdev->link_stat) ||
 903             (prev_hw_addr[0] != mdev->hw_addr[0]) ||
 904             (prev_hw_addr[1] != mdev->hw_addr[1]) ||
 905             (prev_hw_addr[2] != mdev->hw_addr[2]) ||
 906             (prev_hw_addr[3] != mdev->hw_addr[3]) ||
 907             (prev_hw_addr[4] != mdev->hw_addr[4]) ||
 908             (prev_hw_addr[5] != mdev->hw_addr[5]))
 909                 most_deliver_netinfo(&mdev->iface, mdev->link_stat,
 910                                      &mdev->hw_addr[0]);
 911 }
 912
 913 /**
 914  * wq_clear_halt - work queue function
 915  * @wq_obj: work_struct object to execute
 916  *
 917  * This sends a clear_halt to the given USB pipe.
 918  */
 919 static void wq_clear_halt(struct work_struct *wq_obj)
 920 {
 921         struct buf_anchor *anchor;
 922         struct most_dev *mdev;
 923         struct mbo *mbo;
 924         struct urb *urb;
 925         unsigned int channel;
 926         unsigned long flags;
 927
 928         anchor = to_buf_anchor(wq_obj);
 929         urb = anchor->urb;
 930         mbo = urb->context;
 931         mdev = to_mdev(mbo->ifp);
 932         channel = mbo->hdm_channel_id;
 933
 934         if (usb_clear_halt(urb->dev, urb->pipe))
 935                 dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
 936
 937         usb_free_urb(urb);
 938         spin_lock_irqsave(&mdev->anchor_list_lock[channel], flags);
 939         list_del(&anchor->list);
 940         spin_unlock_irqrestore(&mdev->anchor_list_lock[channel], flags);
 941
 942         if (likely(mbo->complete))
 943                 mbo->complete(mbo);
 944         if (mdev->conf[channel].direction & MOST_CH_TX)
 945                 most_resume_enqueue(&mdev->iface, channel);
 946
 947         kfree(anchor);
 948 }
 949
 950 /**
 951  * hdm_usb_fops - file operation table for USB driver
 952  */
 953 static const struct file_operations hdm_usb_fops = {
 954         .owner = THIS_MODULE,
 955 };
 956
 957 /**
 958  * usb_device_id - ID table for HCD device probing
 959  */
 960 static struct usb_device_id usbid[] = {
 961         { USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_BRDG), },
 962         { USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_INIC), },
 963         { } /* Terminating entry */
 964 };
 965
 966 #define MOST_DCI_RO_ATTR(_name) \
 967         struct most_dci_attribute most_dci_attr_##_name = \
 968                 __ATTR(_name, S_IRUGO, show_value, NULL)
 969
 970 #define MOST_DCI_ATTR(_name) \
 971         struct most_dci_attribute most_dci_attr_##_name = \
 972                 __ATTR(_name, S_IRUGO | S_IWUSR, show_value, store_value)
 973
 974 /**
 975  * struct most_dci_attribute - to access the attributes of a dci object
 976  * @attr: attributes of a dci object
 977  * @show: pointer to the show function
 978  * @store: pointer to the store function
 979  */
 980 struct most_dci_attribute {
 981         struct attribute attr;
 982         ssize_t (*show)(struct most_dci_obj *d,
 983                         struct most_dci_attribute *attr,
 984                         char *buf);
 985         ssize_t (*store)(struct most_dci_obj *d,
 986                          struct most_dci_attribute *attr,
 987                          const char *buf,
 988                          size_t count);
 989 };
 990
 991 #define to_dci_attr(a) container_of(a, struct most_dci_attribute, attr)
 992
 993 /**
 994  * dci_attr_show - show function for dci object
 995  * @kobj: pointer to kobject
 996  * @attr: pointer to attribute struct
 997  * @buf: buffer
 998  */
 999 static ssize_t dci_attr_show(struct kobject *kobj, struct attribute *attr,
1000                              char *buf)
1001 {
1002         struct most_dci_attribute *dci_attr = to_dci_attr(attr);
1003         struct most_dci_obj *dci_obj = to_dci_obj(kobj);
1004
1005         if (!dci_attr->show)
1006                 return -EIO;
1007
1008         return dci_attr->show(dci_obj, dci_attr, buf);
1009 }
1010
1011 /**
1012  * dci_attr_store - store function for dci object
1013  * @kobj: pointer to kobject
1014  * @attr: pointer to attribute struct
1015  * @buf: buffer
1016  * @len: length of buffer
1017  */
1018 static ssize_t dci_attr_store(struct kobject *kobj,
1019                               struct attribute *attr,
1020                               const char *buf,
1021                               size_t len)
1022 {
1023         struct most_dci_attribute *dci_attr = to_dci_attr(attr);
1024         struct most_dci_obj *dci_obj = to_dci_obj(kobj);
1025
1026         if (!dci_attr->store)
1027                 return -EIO;
1028
1029         return dci_attr->store(dci_obj, dci_attr, buf, len);
1030 }
1031
1032 static const struct sysfs_ops most_dci_sysfs_ops = {
1033         .show = dci_attr_show,
1034         .store = dci_attr_store,
1035 };
1036
1037 /**
1038  * most_dci_release - release function for dci object
1039  * @kobj: pointer to kobject
1040  *
1041  * This frees the memory allocated for the dci object
1042  */
1043 static void most_dci_release(struct kobject *kobj)
1044 {
1045         struct most_dci_obj *dci_obj = to_dci_obj(kobj);
1046
1047         kfree(dci_obj);
1048 }
1049
1050 static ssize_t show_value(struct most_dci_obj *dci_obj,
1051                           struct most_dci_attribute *attr, char *buf)
1052 {
1053         u16 tmp_val;
1054         u16 reg_addr;
1055         int err;
1056
1057         if (!strcmp(attr->attr.name, "ni_state"))
1058                 reg_addr = DRCI_REG_NI_STATE;
1059         else if (!strcmp(attr->attr.name, "packet_bandwidth"))
1060                 reg_addr = DRCI_REG_PACKET_BW;
1061         else if (!strcmp(attr->attr.name, "node_address"))
1062                 reg_addr = DRCI_REG_NODE_ADDR;
1063         else if (!strcmp(attr->attr.name, "node_position"))
1064                 reg_addr = DRCI_REG_NODE_POS;
1065         else if (!strcmp(attr->attr.name, "mep_filter"))
1066                 reg_addr = DRCI_REG_MEP_FILTER;
1067         else if (!strcmp(attr->attr.name, "mep_hash0"))
1068                 reg_addr = DRCI_REG_HASH_TBL0;
1069         else if (!strcmp(attr->attr.name, "mep_hash1"))
1070                 reg_addr = DRCI_REG_HASH_TBL1;
1071         else if (!strcmp(attr->attr.name, "mep_hash2"))
1072                 reg_addr = DRCI_REG_HASH_TBL2;
1073         else if (!strcmp(attr->attr.name, "mep_hash3"))
1074                 reg_addr = DRCI_REG_HASH_TBL3;
1075         else if (!strcmp(attr->attr.name, "mep_eui48_hi"))
1076                 reg_addr = DRCI_REG_HW_ADDR_HI;
1077         else if (!strcmp(attr->attr.name, "mep_eui48_mi"))
1078                 reg_addr = DRCI_REG_HW_ADDR_MI;
1079         else if (!strcmp(attr->attr.name, "mep_eui48_lo"))
1080                 reg_addr = DRCI_REG_HW_ADDR_LO;
1081         else
1082                 return -EIO;
1083
1084         err = drci_rd_reg(dci_obj->usb_device, reg_addr, &tmp_val);
1085         if (err < 0)
1086                 return err;
1087
1088         return snprintf(buf, PAGE_SIZE, "%04x\n", tmp_val);
1089 }
1090
1091 static ssize_t store_value(struct most_dci_obj *dci_obj,
1092                            struct most_dci_attribute *attr,
1093                            const char *buf, size_t count)
1094 {
1095         u16 val;
1096         u16 reg_addr;
1097         int err;
1098
1099         if (!strcmp(attr->attr.name, "mep_filter"))
1100                 reg_addr = DRCI_REG_MEP_FILTER;
1101         else if (!strcmp(attr->attr.name, "mep_hash0"))
1102                 reg_addr = DRCI_REG_HASH_TBL0;
1103         else if (!strcmp(attr->attr.name, "mep_hash1"))
1104                 reg_addr = DRCI_REG_HASH_TBL1;
1105         else if (!strcmp(attr->attr.name, "mep_hash2"))
1106                 reg_addr = DRCI_REG_HASH_TBL2;
1107         else if (!strcmp(attr->attr.name, "mep_hash3"))
1108                 reg_addr = DRCI_REG_HASH_TBL3;
1109         else if (!strcmp(attr->attr.name, "mep_eui48_hi"))
1110                 reg_addr = DRCI_REG_HW_ADDR_HI;
1111         else if (!strcmp(attr->attr.name, "mep_eui48_mi"))
1112                 reg_addr = DRCI_REG_HW_ADDR_MI;
1113         else if (!strcmp(attr->attr.name, "mep_eui48_lo"))
1114                 reg_addr = DRCI_REG_HW_ADDR_LO;
1115         else
1116                 return -EIO;
1117
1118         err = kstrtou16(buf, 16, &val);
1119         if (err)
1120                 return err;
1121
1122         err = drci_wr_reg(dci_obj->usb_device, reg_addr, val);
1123         if (err < 0)
1124                 return err;
1125
1126         return count;
1127 }
1128
1129 static MOST_DCI_RO_ATTR(ni_state);
1130 static MOST_DCI_RO_ATTR(packet_bandwidth);
1131 static MOST_DCI_RO_ATTR(node_address);
1132 static MOST_DCI_RO_ATTR(node_position);
1133 static MOST_DCI_ATTR(mep_filter);
1134 static MOST_DCI_ATTR(mep_hash0);
1135 static MOST_DCI_ATTR(mep_hash1);
1136 static MOST_DCI_ATTR(mep_hash2);
1137 static MOST_DCI_ATTR(mep_hash3);
1138 static MOST_DCI_ATTR(mep_eui48_hi);
1139 static MOST_DCI_ATTR(mep_eui48_mi);
1140 static MOST_DCI_ATTR(mep_eui48_lo);
1141
1142 /**
1143  * most_dci_def_attrs - array of default attribute files of the dci object
1144  */
1145 static struct attribute *most_dci_def_attrs[] = {
1146         &most_dci_attr_ni_state.attr,
1147         &most_dci_attr_packet_bandwidth.attr,
1148         &most_dci_attr_node_address.attr,
1149         &most_dci_attr_node_position.attr,
1150         &most_dci_attr_mep_filter.attr,
1151         &most_dci_attr_mep_hash0.attr,
1152         &most_dci_attr_mep_hash1.attr,
1153         &most_dci_attr_mep_hash2.attr,
1154         &most_dci_attr_mep_hash3.attr,
1155         &most_dci_attr_mep_eui48_hi.attr,
1156         &most_dci_attr_mep_eui48_mi.attr,
1157         &most_dci_attr_mep_eui48_lo.attr,
1158         NULL,
1159 };
1160
1161 /**
1162  * DCI ktype
1163  */
1164 static struct kobj_type most_dci_ktype = {
1165         .sysfs_ops = &most_dci_sysfs_ops,
1166         .release = most_dci_release,
1167         .default_attrs = most_dci_def_attrs,
1168 };
1169
1170 /**
1171  * create_most_dci_obj - allocates a dci object
1172  * @parent: parent kobject
1173  *
1174  * This creates a dci object and registers it with sysfs.
1175  * Returns a pointer to the object or NULL when something went wrong.
1176  */
1177 static struct
1178 most_dci_obj *create_most_dci_obj(struct kobject *parent)
1179 {
1180         struct most_dci_obj *most_dci;
1181         int retval;
1182
1183         most_dci = kzalloc(sizeof(*most_dci), GFP_KERNEL);
1184         if (!most_dci)
1185                 return NULL;
1186
1187         retval = kobject_init_and_add(&most_dci->kobj, &most_dci_ktype, parent,
1188                                       "dci");
1189         if (retval) {
1190                 kobject_put(&most_dci->kobj);
1191                 return NULL;
1192         }
1193         return most_dci;
1194 }
1195
1196 /**
1197  * destroy_most_dci_obj - DCI object release function
1198  * @p: pointer to dci object
1199  */
1200 static void destroy_most_dci_obj(struct most_dci_obj *p)
1201 {
1202         kobject_put(&p->kobj);
1203 }
1204
1205 /**
1206  * hdm_probe - probe function of USB device driver
1207  * @interface: Interface of the attached USB device
1208  * @id: Pointer to the USB ID table.
1209  *
1210  * This allocates and initializes the device instance, adds the new
1211  * entry to the internal list, scans the USB descriptors and registers
1212  * the interface with the core.
1213  * Additionally, the DCI objects are created and the hardware is sync'd.
1214  *
1215  * Return 0 on success. In case of an error a negative number is returned.
1216  */
1217 static int
1218 hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
1219 {
1220         unsigned int i;
1221         unsigned int num_endpoints;
1222         struct most_channel_capability *tmp_cap;
1223         struct most_dev *mdev;
1224         struct usb_device *usb_dev;
1225         struct device *dev;
1226         struct usb_host_interface *usb_iface_desc;
1227         struct usb_endpoint_descriptor *ep_desc;
1228         int ret = 0;
1229         int err;
1230
1231         usb_iface_desc = interface->cur_altsetting;
1232         usb_dev = interface_to_usbdev(interface);
1233         dev = &usb_dev->dev;
1234         mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
1235         if (!mdev)
1236                 goto exit_ENOMEM;
1237
1238         usb_set_intfdata(interface, mdev);
1239         num_endpoints = usb_iface_desc->desc.bNumEndpoints;
1240         mutex_init(&mdev->io_mutex);
1241         INIT_WORK(&mdev->poll_work_obj, wq_netinfo);
1242         setup_timer(&mdev->link_stat_timer, link_stat_timer_handler,
1243                     (unsigned long)mdev);
1244
1245         mdev->usb_device = usb_dev;
1246         mdev->link_stat_timer.expires = jiffies + (2 * HZ);
1247
1248         mdev->iface.mod = hdm_usb_fops.owner;
1249         mdev->iface.interface = ITYPE_USB;
1250         mdev->iface.configure = hdm_configure_channel;
1251         mdev->iface.request_netinfo = hdm_request_netinfo;
1252         mdev->iface.enqueue = hdm_enqueue;
1253         mdev->iface.poison_channel = hdm_poison_channel;
1254         mdev->iface.description = mdev->description;
1255         mdev->iface.num_channels = num_endpoints;
1256
1257         snprintf(mdev->description, sizeof(mdev->description),
1258                  "usb_device %d-%s:%d.%d",
1259                  usb_dev->bus->busnum,
1260                  usb_dev->devpath,
1261                  usb_dev->config->desc.bConfigurationValue,
1262                  usb_iface_desc->desc.bInterfaceNumber);
1263
1264         mdev->conf = kcalloc(num_endpoints, sizeof(*mdev->conf), GFP_KERNEL);
1265         if (!mdev->conf)
1266                 goto exit_free;
1267
1268         mdev->cap = kcalloc(num_endpoints, sizeof(*mdev->cap), GFP_KERNEL);
1269         if (!mdev->cap)
1270                 goto exit_free1;
1271
1272         mdev->iface.channel_vector = mdev->cap;
1273         mdev->iface.priv = NULL;
1274
1275         mdev->ep_address =
1276                 kcalloc(num_endpoints, sizeof(*mdev->ep_address), GFP_KERNEL);
1277         if (!mdev->ep_address)
1278                 goto exit_free2;
1279
1280         mdev->anchor_list =
1281                 kcalloc(num_endpoints, sizeof(*mdev->anchor_list), GFP_KERNEL);
1282         if (!mdev->anchor_list)
1283                 goto exit_free3;
1284
1285         tmp_cap = mdev->cap;
1286         for (i = 0; i < num_endpoints; i++) {
1287                 ep_desc = &usb_iface_desc->endpoint[i].desc;
1288                 mdev->ep_address[i] = ep_desc->bEndpointAddress;
1289                 mdev->padding_active[i] = false;
1290                 mdev->is_channel_healthy[i] = true;
1291
1292                 snprintf(&mdev->suffix[i][0], MAX_SUFFIX_LEN, "ep%02x",
1293                          mdev->ep_address[i]);
1294
1295                 tmp_cap->name_suffix = &mdev->suffix[i][0];
1296                 tmp_cap->buffer_size_packet = MAX_BUF_SIZE;
1297                 tmp_cap->buffer_size_streaming = MAX_BUF_SIZE;
1298                 tmp_cap->num_buffers_packet = BUF_CHAIN_SIZE;
1299                 tmp_cap->num_buffers_streaming = BUF_CHAIN_SIZE;
1300                 tmp_cap->data_type = MOST_CH_CONTROL | MOST_CH_ASYNC |
1301                                      MOST_CH_ISOC_AVP | MOST_CH_SYNC;
1302                 if (ep_desc->bEndpointAddress & USB_DIR_IN)
1303                         tmp_cap->direction = MOST_CH_RX;
1304                 else
1305                         tmp_cap->direction = MOST_CH_TX;
1306                 tmp_cap++;
1307                 INIT_LIST_HEAD(&mdev->anchor_list[i]);
1308                 spin_lock_init(&mdev->anchor_list_lock[i]);
1309                 err = drci_wr_reg(usb_dev,
1310                                   DRCI_REG_BASE + DRCI_COMMAND +
1311                                   ep_desc->bEndpointAddress * 16,
1312                                   1);
1313                 if (err < 0)
1314                         pr_warn("DCI Sync for EP %02x failed",
1315                                 ep_desc->bEndpointAddress);
1316         }
1317         dev_notice(dev, "claimed gadget: Vendor=%4.4x ProdID=%4.4x Bus=%02x Device=%02x\n",
1318                    le16_to_cpu(usb_dev->descriptor.idVendor),
1319                    le16_to_cpu(usb_dev->descriptor.idProduct),
1320                    usb_dev->bus->busnum,
1321                    usb_dev->devnum);
1322
1323         dev_notice(dev, "device path: /sys/bus/usb/devices/%d-%s:%d.%d\n",
1324                    usb_dev->bus->busnum,
1325                    usb_dev->devpath,
1326                    usb_dev->config->desc.bConfigurationValue,
1327                    usb_iface_desc->desc.bInterfaceNumber);
1328
1329         mdev->parent = most_register_interface(&mdev->iface);
1330         if (IS_ERR(mdev->parent)) {
1331                 ret = PTR_ERR(mdev->parent);
1332                 goto exit_free4;
1333         }
1334
1335         mutex_lock(&mdev->io_mutex);
1336         if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_INIC) {
1337                 /* this increments the reference count of the instance
1338                  * object of the core
1339                  */
1340                 mdev->dci = create_most_dci_obj(mdev->parent);
1341                 if (!mdev->dci) {
1342                         mutex_unlock(&mdev->io_mutex);
1343                         most_deregister_interface(&mdev->iface);
1344                         ret = -ENOMEM;
1345                         goto exit_free4;
1346                 }
1347
1348                 kobject_uevent(&mdev->dci->kobj, KOBJ_ADD);
1349                 mdev->dci->usb_device = mdev->usb_device;
1350         }
1351         mutex_unlock(&mdev->io_mutex);
1352         return 0;
1353
1354 exit_free4:
1355         kfree(mdev->anchor_list);
1356 exit_free3:
1357         kfree(mdev->ep_address);
1358 exit_free2:
1359         kfree(mdev->cap);
1360 exit_free1:
1361         kfree(mdev->conf);
1362 exit_free:
1363         kfree(mdev);
1364 exit_ENOMEM:
1365         if (ret == 0 || ret == -ENOMEM) {
1366                 ret = -ENOMEM;
1367                 dev_err(dev, "out of memory\n");
1368         }
1369         return ret;
1370 }
1371
1372 /**
1373  * hdm_disconnect - disconnect function of USB device driver
1374  * @interface: Interface of the attached USB device
1375  *
1376  * This deregisters the interface with the core, removes the kernel timer
1377  * and frees resources.
1378  *
1379  * Context: hub kernel thread
1380  */
1381 static void hdm_disconnect(struct usb_interface *interface)
1382 {
1383         struct most_dev *mdev;
1384
1385         mdev = usb_get_intfdata(interface);
1386         mutex_lock(&mdev->io_mutex);
1387         usb_set_intfdata(interface, NULL);
1388         mdev->usb_device = NULL;
1389         mutex_unlock(&mdev->io_mutex);
1390
1391         del_timer_sync(&mdev->link_stat_timer);
1392         cancel_work_sync(&mdev->poll_work_obj);
1393
1394         destroy_most_dci_obj(mdev->dci);
1395         most_deregister_interface(&mdev->iface);
1396
1397         kfree(mdev->anchor_list);
1398         kfree(mdev->cap);
1399         kfree(mdev->conf);
1400         kfree(mdev->ep_address);
1401         kfree(mdev);
1402 }
1403
1404 static struct usb_driver hdm_usb = {
1405         .name = "hdm_usb",
1406         .id_table = usbid,
1407         .probe = hdm_probe,
1408         .disconnect = hdm_disconnect,
1409 };
1410
1411 static int __init hdm_usb_init(void)
1412 {
1413         pr_info("hdm_usb_init()\n");
1414         if (usb_register(&hdm_usb)) {
1415                 pr_err("could not register hdm_usb driver\n");
1416                 return -EIO;
1417         }
1418         schedule_usb_work = create_workqueue("hdmu_work");
1419         if (!schedule_usb_work) {
1420                 pr_err("could not create workqueue\n");
1421                 usb_deregister(&hdm_usb);
1422                 return -ENOMEM;
1423         }
1424         return 0;
1425 }
1426
1427 static void __exit hdm_usb_exit(void)
1428 {
1429         pr_info("hdm_usb_exit()\n");
1430         destroy_workqueue(schedule_usb_work);
1431         usb_deregister(&hdm_usb);
1432 }
1433
1434 module_init(hdm_usb_init);
1435 module_exit(hdm_usb_exit);
1436 MODULE_LICENSE("GPL");
1437 MODULE_AUTHOR("Christian Gromm <christian.gromm@microchip.com>");
1438 MODULE_DESCRIPTION("HDM_4_USB");