drivers/net/wimax/i2400m/usb.c

   1 /*
   2  * Intel Wireless WiMAX Connection 2400m
   3  * Linux driver model glue for USB device, reset & fw upload
   4  *
   5  *
   6  * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>
   7  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   8  * Yanir Lubetkin <yanirx.lubetkin@intel.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License version
  12  * 2 as published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  22  * 02110-1301, USA.
  23  *
  24  *
  25  * See i2400m-usb.h for a general description of this driver.
  26  *
  27  * This file implements driver model glue, and hook ups for the
  28  * generic driver to implement the bus-specific functions (device
  29  * communication setup/tear down, firmware upload and resetting).
  30  *
  31  * ROADMAP
  32  *
  33  * i2400mu_probe()
  34  *   alloc_netdev()...
  35  *     i2400mu_netdev_setup()
  36  *       i2400mu_init()
  37  *       i2400m_netdev_setup()
  38  *   i2400m_setup()...
  39  *
  40  * i2400mu_disconnect
  41  *   i2400m_release()
  42  *   free_netdev()
  43  *
  44  * i2400mu_suspend()
  45  *   i2400m_cmd_enter_powersave()
  46  *   i2400mu_notification_release()
  47  *
  48  * i2400mu_resume()
  49  *   i2400mu_notification_setup()
  50  *
  51  * i2400mu_bus_dev_start()        Called by i2400m_dev_start() [who is
  52  *   i2400mu_tx_setup()           called by i2400m_setup()]
  53  *   i2400mu_rx_setup()
  54  *   i2400mu_notification_setup()
  55  *
  56  * i2400mu_bus_dev_stop()         Called by i2400m_dev_stop() [who is
  57  *   i2400mu_notification_release()  called by i2400m_release()]
  58  *   i2400mu_rx_release()
  59  *   i2400mu_tx_release()
  60  *
  61  * i2400mu_bus_reset()            Called by i2400m_reset
  62  *   __i2400mu_reset()
  63  *     __i2400mu_send_barker()
  64  *   usb_reset_device()
  65  */
  66 #include "i2400m-usb.h"
  67 #include <linux/wimax/i2400m.h>
  68 #include <linux/debugfs.h>
  69 #include <linux/slab.h>
  70 #include <linux/module.h>
  71
  72
  73 #define D_SUBMODULE usb
  74 #include "usb-debug-levels.h"
  75
  76 static char i2400mu_debug_params[128];
  77 module_param_string(debug, i2400mu_debug_params, sizeof(i2400mu_debug_params),
  78                     0644);
  79 MODULE_PARM_DESC(debug,
  80                  "String of space-separated NAME:VALUE pairs, where NAMEs "
  81                  "are the different debug submodules and VALUE are the "
  82                  "initial debug value to set.");
  83
  84 /* Our firmware file name */
  85 static const char *i2400mu_bus_fw_names_5x50[] = {
  86 #define I2400MU_FW_FILE_NAME_v1_5 "i2400m-fw-usb-1.5.sbcf"
  87         I2400MU_FW_FILE_NAME_v1_5,
  88 #define I2400MU_FW_FILE_NAME_v1_4 "i2400m-fw-usb-1.4.sbcf"
  89         I2400MU_FW_FILE_NAME_v1_4,
  90         NULL,
  91 };
  92
  93
  94 static const char *i2400mu_bus_fw_names_6050[] = {
  95 #define I6050U_FW_FILE_NAME_v1_5 "i6050-fw-usb-1.5.sbcf"
  96         I6050U_FW_FILE_NAME_v1_5,
  97         NULL,
  98 };
  99
 100
 101 static
 102 int i2400mu_bus_dev_start(struct i2400m *i2400m)
 103 {
 104         int result;
 105         struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
 106         struct device *dev = &i2400mu->usb_iface->dev;
 107
 108         d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
 109         result = i2400mu_tx_setup(i2400mu);
 110         if (result < 0)
 111                 goto error_usb_tx_setup;
 112         result = i2400mu_rx_setup(i2400mu);
 113         if (result < 0)
 114                 goto error_usb_rx_setup;
 115         result = i2400mu_notification_setup(i2400mu);
 116         if (result < 0)
 117                 goto error_notif_setup;
 118         d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
 119         return result;
 120
 121 error_notif_setup:
 122         i2400mu_rx_release(i2400mu);
 123 error_usb_rx_setup:
 124         i2400mu_tx_release(i2400mu);
 125 error_usb_tx_setup:
 126         d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
 127         return result;
 128 }
 129
 130
 131 static
 132 void i2400mu_bus_dev_stop(struct i2400m *i2400m)
 133 {
 134         struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
 135         struct device *dev = &i2400mu->usb_iface->dev;
 136
 137         d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
 138         i2400mu_notification_release(i2400mu);
 139         i2400mu_rx_release(i2400mu);
 140         i2400mu_tx_release(i2400mu);
 141         d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
 142 }
 143
 144
 145 /*
 146  * Sends a barker buffer to the device
 147  *
 148  * This helper will allocate a kmalloced buffer and use it to transmit
 149  * (then free it). Reason for this is that other arches cannot use
 150  * stack/vmalloc/text areas for DMA transfers.
 151  *
 152  * Error recovery here is simpler: anything is considered a hard error
 153  * and will move the reset code to use a last-resort bus-based reset.
 154  */
 155 static
 156 int __i2400mu_send_barker(struct i2400mu *i2400mu,
 157                           const __le32 *barker,
 158                           size_t barker_size,
 159                           unsigned endpoint)
 160 {
 161         struct usb_endpoint_descriptor *epd = NULL;
 162         int pipe, actual_len, ret;
 163         struct device *dev = &i2400mu->usb_iface->dev;
 164         void *buffer;
 165         int do_autopm = 1;
 166
 167         ret = usb_autopm_get_interface(i2400mu->usb_iface);
 168         if (ret < 0) {
 169                 dev_err(dev, "RESET: can't get autopm: %d\n", ret);
 170                 do_autopm = 0;
 171         }
 172         ret = -ENOMEM;
 173         buffer = kmalloc(barker_size, GFP_KERNEL);
 174         if (buffer == NULL)
 175                 goto error_kzalloc;
 176         epd = usb_get_epd(i2400mu->usb_iface, endpoint);
 177         pipe = usb_sndbulkpipe(i2400mu->usb_dev, epd->bEndpointAddress);
 178         memcpy(buffer, barker, barker_size);
 179 retry:
 180         ret = usb_bulk_msg(i2400mu->usb_dev, pipe, buffer, barker_size,
 181                            &actual_len, 200);
 182         switch (ret) {
 183         case 0:
 184                 if (actual_len != barker_size) {        /* Too short? drop it */
 185                         dev_err(dev, "E: %s: short write (%d B vs %zu "
 186                                 "expected)\n",
 187                                 __func__, actual_len, barker_size);
 188                         ret = -EIO;
 189                 }
 190                 break;
 191         case -EPIPE:
 192                 /*
 193                  * Stall -- maybe the device is choking with our
 194                  * requests. Clear it and give it some time. If they
 195                  * happen to often, it might be another symptom, so we
 196                  * reset.
 197                  *
 198                  * No error handling for usb_clear_halt(0; if it
 199                  * works, the retry works; if it fails, this switch
 200                  * does the error handling for us.
 201                  */
 202                 if (edc_inc(&i2400mu->urb_edc,
 203                             10 * EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
 204                         dev_err(dev, "E: %s: too many stalls in "
 205                                 "URB; resetting device\n", __func__);
 206                         usb_queue_reset_device(i2400mu->usb_iface);
 207                         /* fallthrough */
 208                 } else {
 209                         usb_clear_halt(i2400mu->usb_dev, pipe);
 210                         msleep(10);     /* give the device some time */
 211                         goto retry;
 212                 }
 213         case -EINVAL:                   /* while removing driver */
 214         case -ENODEV:                   /* dev disconnect ... */
 215         case -ENOENT:                   /* just ignore it */
 216         case -ESHUTDOWN:                /* and exit */
 217         case -ECONNRESET:
 218                 ret = -ESHUTDOWN;
 219                 break;
 220         default:                        /* Some error? */
 221                 if (edc_inc(&i2400mu->urb_edc,
 222                             EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
 223                         dev_err(dev, "E: %s: maximum errors in URB "
 224                                 "exceeded; resetting device\n",
 225                                 __func__);
 226                         usb_queue_reset_device(i2400mu->usb_iface);
 227                 } else {
 228                         dev_warn(dev, "W: %s: cannot send URB: %d\n",
 229                                  __func__, ret);
 230                         goto retry;
 231                 }
 232         }
 233         kfree(buffer);
 234 error_kzalloc:
 235         if (do_autopm)
 236                 usb_autopm_put_interface(i2400mu->usb_iface);
 237         return ret;
 238 }
 239
 240
 241 /*
 242  * Reset a device at different levels (warm, cold or bus)
 243  *
 244  * @i2400m: device descriptor
 245  * @reset_type: soft, warm or bus reset (I2400M_RT_WARM/SOFT/BUS)
 246  *
 247  * Warm and cold resets get a USB reset if they fail.
 248  *
 249  * Warm reset:
 250  *
 251  * The device will be fully reset internally, but won't be
 252  * disconnected from the USB bus (so no reenumeration will
 253  * happen). Firmware upload will be necessary.
 254  *
 255  * The device will send a reboot barker in the notification endpoint
 256  * that will trigger the driver to reinitialize the state
 257  * automatically from notif.c:i2400m_notification_grok() into
 258  * i2400m_dev_bootstrap_delayed().
 259  *
 260  * Cold and bus (USB) reset:
 261  *
 262  * The device will be fully reset internally, disconnected from the
 263  * USB bus an a reenumeration will happen. Firmware upload will be
 264  * necessary. Thus, we don't do any locking or struct
 265  * reinitialization, as we are going to be fully disconnected and
 266  * reenumerated.
 267  *
 268  * Note we need to return -ENODEV if a warm reset was requested and we
 269  * had to resort to a bus reset. See i2400m_op_reset(), wimax_reset()
 270  * and wimax_dev->op_reset.
 271  *
 272  * WARNING: no driver state saved/fixed
 273  */
 274 static
 275 int i2400mu_bus_reset(struct i2400m *i2400m, enum i2400m_reset_type rt)
 276 {
 277         int result;
 278         struct i2400mu *i2400mu =
 279                 container_of(i2400m, struct i2400mu, i2400m);
 280         struct device *dev = i2400m_dev(i2400m);
 281         static const __le32 i2400m_WARM_BOOT_BARKER[4] = {
 282                 cpu_to_le32(I2400M_WARM_RESET_BARKER),
 283                 cpu_to_le32(I2400M_WARM_RESET_BARKER),
 284                 cpu_to_le32(I2400M_WARM_RESET_BARKER),
 285                 cpu_to_le32(I2400M_WARM_RESET_BARKER),
 286         };
 287         static const __le32 i2400m_COLD_BOOT_BARKER[4] = {
 288                 cpu_to_le32(I2400M_COLD_RESET_BARKER),
 289                 cpu_to_le32(I2400M_COLD_RESET_BARKER),
 290                 cpu_to_le32(I2400M_COLD_RESET_BARKER),
 291                 cpu_to_le32(I2400M_COLD_RESET_BARKER),
 292         };
 293
 294         d_fnstart(3, dev, "(i2400m %p rt %u)\n", i2400m, rt);
 295         if (rt == I2400M_RT_WARM)
 296                 result = __i2400mu_send_barker(
 297                         i2400mu, i2400m_WARM_BOOT_BARKER,
 298                         sizeof(i2400m_WARM_BOOT_BARKER),
 299                         i2400mu->endpoint_cfg.bulk_out);
 300         else if (rt == I2400M_RT_COLD)
 301                 result = __i2400mu_send_barker(
 302                         i2400mu, i2400m_COLD_BOOT_BARKER,
 303                         sizeof(i2400m_COLD_BOOT_BARKER),
 304                         i2400mu->endpoint_cfg.reset_cold);
 305         else if (rt == I2400M_RT_BUS) {
 306                 result = usb_reset_device(i2400mu->usb_dev);
 307                 switch (result) {
 308                 case 0:
 309                 case -EINVAL:   /* device is gone */
 310                 case -ENODEV:
 311                 case -ENOENT:
 312                 case -ESHUTDOWN:
 313                         result = 0;
 314                         break;  /* We assume the device is disconnected */
 315                 default:
 316                         dev_err(dev, "USB reset failed (%d), giving up!\n",
 317                                 result);
 318                 }
 319         } else {
 320                 result = -EINVAL;       /* shut gcc up in certain arches */
 321                 BUG();
 322         }
 323         if (result < 0
 324             && result != -EINVAL        /* device is gone */
 325             && rt != I2400M_RT_BUS) {
 326                 /*
 327                  * Things failed -- resort to lower level reset, that
 328                  * we queue in another context; the reason for this is
 329                  * that the pre and post reset functionality requires
 330                  * the i2400m->init_mutex; RT_WARM and RT_COLD can
 331                  * come from areas where i2400m->init_mutex is taken.
 332                  */
 333                 dev_err(dev, "%s reset failed (%d); trying USB reset\n",
 334                         rt == I2400M_RT_WARM ? "warm" : "cold", result);
 335                 usb_queue_reset_device(i2400mu->usb_iface);
 336                 result = -ENODEV;
 337         }
 338         d_fnend(3, dev, "(i2400m %p rt %u) = %d\n", i2400m, rt, result);
 339         return result;
 340 }
 341
 342
 343 static
 344 void i2400mu_netdev_setup(struct net_device *net_dev)
 345 {
 346         struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 347         struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
 348         i2400mu_init(i2400mu);
 349         i2400m_netdev_setup(net_dev);
 350 }
 351
 352
 353 /*
 354  * Debug levels control; see debug.h
 355  */
 356 struct d_level D_LEVEL[] = {
 357         D_SUBMODULE_DEFINE(usb),
 358         D_SUBMODULE_DEFINE(fw),
 359         D_SUBMODULE_DEFINE(notif),
 360         D_SUBMODULE_DEFINE(rx),
 361         D_SUBMODULE_DEFINE(tx),
 362 };
 363 size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);
 364
 365
 366 #define __debugfs_register(prefix, name, parent)                        \
 367 do {                                                                    \
 368         result = d_level_register_debugfs(prefix, name, parent);        \
 369         if (result < 0)                                                 \
 370                 goto error;                                             \
 371 } while (0)
 372
 373
 374 static
 375 int i2400mu_debugfs_add(struct i2400mu *i2400mu)
 376 {
 377         int result;
 378         struct device *dev = &i2400mu->usb_iface->dev;
 379         struct dentry *dentry = i2400mu->i2400m.wimax_dev.debugfs_dentry;
 380         struct dentry *fd;
 381
 382         dentry = debugfs_create_dir("i2400m-usb", dentry);
 383         result = PTR_ERR(dentry);
 384         if (IS_ERR(dentry)) {
 385                 if (result == -ENODEV)
 386                         result = 0;     /* No debugfs support */
 387                 goto error;
 388         }
 389         i2400mu->debugfs_dentry = dentry;
 390         __debugfs_register("dl_", usb, dentry);
 391         __debugfs_register("dl_", fw, dentry);
 392         __debugfs_register("dl_", notif, dentry);
 393         __debugfs_register("dl_", rx, dentry);
 394         __debugfs_register("dl_", tx, dentry);
 395
 396         /* Don't touch these if you don't know what you are doing */
 397         fd = debugfs_create_u8("rx_size_auto_shrink", 0600, dentry,
 398                                &i2400mu->rx_size_auto_shrink);
 399         result = PTR_ERR(fd);
 400         if (IS_ERR(fd) && result != -ENODEV) {
 401                 dev_err(dev, "Can't create debugfs entry "
 402                         "rx_size_auto_shrink: %d\n", result);
 403                 goto error;
 404         }
 405
 406         fd = debugfs_create_size_t("rx_size", 0600, dentry,
 407                                    &i2400mu->rx_size);
 408         result = PTR_ERR(fd);
 409         if (IS_ERR(fd) && result != -ENODEV) {
 410                 dev_err(dev, "Can't create debugfs entry "
 411                         "rx_size: %d\n", result);
 412                 goto error;
 413         }
 414
 415         return 0;
 416
 417 error:
 418         debugfs_remove_recursive(i2400mu->debugfs_dentry);
 419         return result;
 420 }
 421
 422
 423 static struct device_type i2400mu_type = {
 424         .name   = "wimax",
 425 };
 426
 427 /*
 428  * Probe a i2400m interface and register it
 429  *
 430  * @iface:   USB interface to link to
 431  * @id:      USB class/subclass/protocol id
 432  * @returns: 0 if ok, < 0 errno code on error.
 433  *
 434  * Alloc a net device, initialize the bus-specific details and then
 435  * calls the bus-generic initialization routine. That will register
 436  * the wimax and netdev devices, upload the firmware [using
 437  * _bus_bm_*()], call _bus_dev_start() to finalize the setup of the
 438  * communication with the device and then will start to talk to it to
 439  * finnish setting it up.
 440  */
 441 static
 442 int i2400mu_probe(struct usb_interface *iface,
 443                   const struct usb_device_id *id)
 444 {
 445         int result;
 446         struct net_device *net_dev;
 447         struct device *dev = &iface->dev;
 448         struct i2400m *i2400m;
 449         struct i2400mu *i2400mu;
 450         struct usb_device *usb_dev = interface_to_usbdev(iface);
 451
 452         if (usb_dev->speed != USB_SPEED_HIGH)
 453                 dev_err(dev, "device not connected as high speed\n");
 454
 455         /* Allocate instance [calls i2400m_netdev_setup() on it]. */
 456         result = -ENOMEM;
 457         net_dev = alloc_netdev(sizeof(*i2400mu), "wmx%d",
 458                                i2400mu_netdev_setup);
 459         if (net_dev == NULL) {
 460                 dev_err(dev, "no memory for network device instance\n");
 461                 goto error_alloc_netdev;
 462         }
 463         SET_NETDEV_DEV(net_dev, dev);
 464         SET_NETDEV_DEVTYPE(net_dev, &i2400mu_type);
 465         i2400m = net_dev_to_i2400m(net_dev);
 466         i2400mu = container_of(i2400m, struct i2400mu, i2400m);
 467         i2400m->wimax_dev.net_dev = net_dev;
 468         i2400mu->usb_dev = usb_get_dev(usb_dev);
 469         i2400mu->usb_iface = iface;
 470         usb_set_intfdata(iface, i2400mu);
 471
 472         i2400m->bus_tx_block_size = I2400MU_BLK_SIZE;
 473         /*
 474          * Room required in the Tx queue for USB message to accommodate
 475          * a smallest payload while allocating header space is 16 bytes.
 476          * Adding this room  for the new tx message increases the
 477          * possibilities of including any payload with size <= 16 bytes.
 478          */
 479         i2400m->bus_tx_room_min = I2400MU_BLK_SIZE;
 480         i2400m->bus_pl_size_max = I2400MU_PL_SIZE_MAX;
 481         i2400m->bus_setup = NULL;
 482         i2400m->bus_dev_start = i2400mu_bus_dev_start;
 483         i2400m->bus_dev_stop = i2400mu_bus_dev_stop;
 484         i2400m->bus_release = NULL;
 485         i2400m->bus_tx_kick = i2400mu_bus_tx_kick;
 486         i2400m->bus_reset = i2400mu_bus_reset;
 487         i2400m->bus_bm_retries = I2400M_USB_BOOT_RETRIES;
 488         i2400m->bus_bm_cmd_send = i2400mu_bus_bm_cmd_send;
 489         i2400m->bus_bm_wait_for_ack = i2400mu_bus_bm_wait_for_ack;
 490         i2400m->bus_bm_mac_addr_impaired = 0;
 491
 492         switch (id->idProduct) {
 493         case USB_DEVICE_ID_I6050:
 494         case USB_DEVICE_ID_I6050_2:
 495         case USB_DEVICE_ID_I6250:
 496                 i2400mu->i6050 = 1;
 497                 break;
 498         default:
 499                 break;
 500         }
 501
 502         if (i2400mu->i6050) {
 503                 i2400m->bus_fw_names = i2400mu_bus_fw_names_6050;
 504                 i2400mu->endpoint_cfg.bulk_out = 0;
 505                 i2400mu->endpoint_cfg.notification = 3;
 506                 i2400mu->endpoint_cfg.reset_cold = 2;
 507                 i2400mu->endpoint_cfg.bulk_in = 1;
 508         } else {
 509                 i2400m->bus_fw_names = i2400mu_bus_fw_names_5x50;
 510                 i2400mu->endpoint_cfg.bulk_out = 0;
 511                 i2400mu->endpoint_cfg.notification = 1;
 512                 i2400mu->endpoint_cfg.reset_cold = 2;
 513                 i2400mu->endpoint_cfg.bulk_in = 3;
 514         }
 515 #ifdef CONFIG_PM
 516         iface->needs_remote_wakeup = 1;         /* autosuspend (15s delay) */
 517         device_init_wakeup(dev, 1);
 518         pm_runtime_set_autosuspend_delay(&usb_dev->dev, 15000);
 519         usb_enable_autosuspend(usb_dev);
 520 #endif
 521
 522         result = i2400m_setup(i2400m, I2400M_BRI_MAC_REINIT);
 523         if (result < 0) {
 524                 dev_err(dev, "cannot setup device: %d\n", result);
 525                 goto error_setup;
 526         }
 527         result = i2400mu_debugfs_add(i2400mu);
 528         if (result < 0) {
 529                 dev_err(dev, "Can't register i2400mu's debugfs: %d\n", result);
 530                 goto error_debugfs_add;
 531         }
 532         return 0;
 533
 534 error_debugfs_add:
 535         i2400m_release(i2400m);
 536 error_setup:
 537         usb_set_intfdata(iface, NULL);
 538         usb_put_dev(i2400mu->usb_dev);
 539         free_netdev(net_dev);
 540 error_alloc_netdev:
 541         return result;
 542 }
 543
 544
 545 /*
 546  * Disconect a i2400m from the system.
 547  *
 548  * i2400m_stop() has been called before, so al the rx and tx contexts
 549  * have been taken down already. Make sure the queue is stopped,
 550  * unregister netdev and i2400m, free and kill.
 551  */
 552 static
 553 void i2400mu_disconnect(struct usb_interface *iface)
 554 {
 555         struct i2400mu *i2400mu = usb_get_intfdata(iface);
 556         struct i2400m *i2400m = &i2400mu->i2400m;
 557         struct net_device *net_dev = i2400m->wimax_dev.net_dev;
 558         struct device *dev = &iface->dev;
 559
 560         d_fnstart(3, dev, "(iface %p i2400m %p)\n", iface, i2400m);
 561
 562         debugfs_remove_recursive(i2400mu->debugfs_dentry);
 563         i2400m_release(i2400m);
 564         usb_set_intfdata(iface, NULL);
 565         usb_put_dev(i2400mu->usb_dev);
 566         free_netdev(net_dev);
 567         d_fnend(3, dev, "(iface %p i2400m %p) = void\n", iface, i2400m);
 568 }
 569
 570
 571 /*
 572  * Get the device ready for USB port or system standby and hibernation
 573  *
 574  * USB port and system standby are handled the same.
 575  *
 576  * When the system hibernates, the USB device is powered down and then
 577  * up, so we don't really have to do much here, as it will be seen as
 578  * a reconnect. Still for simplicity we consider this case the same as
 579  * suspend, so that the device has a chance to do notify the base
 580  * station (if connected).
 581  *
 582  * So at the end, the three cases require common handling.
 583  *
 584  * If at the time of this call the device's firmware is not loaded,
 585  * nothing has to be done. Note we can be "loose" about not reading
 586  * i2400m->updown under i2400m->init_mutex. If it happens to change
 587  * inmediately, other parts of the call flow will fail and effectively
 588  * catch it.
 589  *
 590  * If the firmware is loaded, we need to:
 591  *
 592  *  - tell the device to go into host interface power save mode, wait
 593  *    for it to ack
 594  *
 595  *    This is quite more interesting than it is; we need to execute a
 596  *    command, but this time, we don't want the code in usb-{tx,rx}.c
 597  *    to call the usb_autopm_get/put_interface() barriers as it'd
 598  *    deadlock, so we need to decrement i2400mu->do_autopm, that acts
 599  *    as a poor man's semaphore. Ugly, but it works.
 600  *
 601  *    As well, the device might refuse going to sleep for whichever
 602  *    reason. In this case we just fail. For system suspend/hibernate,
 603  *    we *can't* fail. We check PMSG_IS_AUTO to see if the
 604  *    suspend call comes from the USB stack or from the system and act
 605  *    in consequence.
 606  *
 607  *  - stop the notification endpoint polling
 608  */
 609 static
 610 int i2400mu_suspend(struct usb_interface *iface, pm_message_t pm_msg)
 611 {
 612         int result = 0;
 613         struct device *dev = &iface->dev;
 614         struct i2400mu *i2400mu = usb_get_intfdata(iface);
 615         unsigned is_autosuspend = 0;
 616         struct i2400m *i2400m = &i2400mu->i2400m;
 617
 618 #ifdef CONFIG_PM
 619         if (PMSG_IS_AUTO(pm_msg))
 620                 is_autosuspend = 1;
 621 #endif
 622
 623         d_fnstart(3, dev, "(iface %p pm_msg %u)\n", iface, pm_msg.event);
 624         rmb();          /* see i2400m->updown's documentation  */
 625         if (i2400m->updown == 0)
 626                 goto no_firmware;
 627         if (i2400m->state == I2400M_SS_DATA_PATH_CONNECTED && is_autosuspend) {
 628                 /* ugh -- the device is connected and this suspend
 629                  * request is an autosuspend one (not a system standby
 630                  * / hibernate).
 631                  *
 632                  * The only way the device can go to standby is if the
 633                  * link with the base station is in IDLE mode; that
 634                  * were the case, we'd be in status
 635                  * I2400M_SS_CONNECTED_IDLE. But we are not.
 636                  *
 637                  * If we *tell* him to go power save now, it'll reset
 638                  * as a precautionary measure, so if this is an
 639                  * autosuspend thing, say no and it'll come back
 640                  * later, when the link is IDLE
 641                  */
 642                 result = -EBADF;
 643                 d_printf(1, dev, "fw up, link up, not-idle, autosuspend: "
 644                          "not entering powersave\n");
 645                 goto error_not_now;
 646         }
 647         d_printf(1, dev, "fw up: entering powersave\n");
 648         atomic_dec(&i2400mu->do_autopm);
 649         result = i2400m_cmd_enter_powersave(i2400m);
 650         atomic_inc(&i2400mu->do_autopm);
 651         if (result < 0 && !is_autosuspend) {
 652                 /* System suspend, can't fail */
 653                 dev_err(dev, "failed to suspend, will reset on resume\n");
 654                 result = 0;
 655         }
 656         if (result < 0)
 657                 goto error_enter_powersave;
 658         i2400mu_notification_release(i2400mu);
 659         d_printf(1, dev, "powersave requested\n");
 660 error_enter_powersave:
 661 error_not_now:
 662 no_firmware:
 663         d_fnend(3, dev, "(iface %p pm_msg %u) = %d\n",
 664                 iface, pm_msg.event, result);
 665         return result;
 666 }
 667
 668
 669 static
 670 int i2400mu_resume(struct usb_interface *iface)
 671 {
 672         int ret = 0;
 673         struct device *dev = &iface->dev;
 674         struct i2400mu *i2400mu = usb_get_intfdata(iface);
 675         struct i2400m *i2400m = &i2400mu->i2400m;
 676
 677         d_fnstart(3, dev, "(iface %p)\n", iface);
 678         rmb();          /* see i2400m->updown's documentation  */
 679         if (i2400m->updown == 0) {
 680                 d_printf(1, dev, "fw was down, no resume neeed\n");
 681                 goto out;
 682         }
 683         d_printf(1, dev, "fw was up, resuming\n");
 684         i2400mu_notification_setup(i2400mu);
 685         /* USB has flow control, so we don't need to give it time to
 686          * come back; otherwise, we'd use something like a get-state
 687          * command... */
 688 out:
 689         d_fnend(3, dev, "(iface %p) = %d\n", iface, ret);
 690         return ret;
 691 }
 692
 693
 694 static
 695 int i2400mu_reset_resume(struct usb_interface *iface)
 696 {
 697         int result;
 698         struct device *dev = &iface->dev;
 699         struct i2400mu *i2400mu = usb_get_intfdata(iface);
 700         struct i2400m *i2400m = &i2400mu->i2400m;
 701
 702         d_fnstart(3, dev, "(iface %p)\n", iface);
 703         result = i2400m_dev_reset_handle(i2400m, "device reset on resume");
 704         d_fnend(3, dev, "(iface %p) = %d\n", iface, result);
 705         return result < 0 ? result : 0;
 706 }
 707
 708
 709 /*
 710  * Another driver or user space is triggering a reset on the device
 711  * which contains the interface passed as an argument. Cease IO and
 712  * save any device state you need to restore.
 713  *
 714  * If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if
 715  * you are in atomic context.
 716  */
 717 static
 718 int i2400mu_pre_reset(struct usb_interface *iface)
 719 {
 720         struct i2400mu *i2400mu = usb_get_intfdata(iface);
 721         return i2400m_pre_reset(&i2400mu->i2400m);
 722 }
 723
 724
 725 /*
 726  * The reset has completed.  Restore any saved device state and begin
 727  * using the device again.
 728  *
 729  * If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if
 730  * you are in atomic context.
 731  */
 732 static
 733 int i2400mu_post_reset(struct usb_interface *iface)
 734 {
 735         struct i2400mu *i2400mu = usb_get_intfdata(iface);
 736         return i2400m_post_reset(&i2400mu->i2400m);
 737 }
 738
 739
 740 static
 741 struct usb_device_id i2400mu_id_table[] = {
 742         { USB_DEVICE(0x8086, USB_DEVICE_ID_I6050) },
 743         { USB_DEVICE(0x8086, USB_DEVICE_ID_I6050_2) },
 744         { USB_DEVICE(0x8086, USB_DEVICE_ID_I6250) },
 745         { USB_DEVICE(0x8086, 0x0181) },
 746         { USB_DEVICE(0x8086, 0x1403) },
 747         { USB_DEVICE(0x8086, 0x1405) },
 748         { USB_DEVICE(0x8086, 0x0180) },
 749         { USB_DEVICE(0x8086, 0x0182) },
 750         { USB_DEVICE(0x8086, 0x1406) },
 751         { USB_DEVICE(0x8086, 0x1403) },
 752         { },
 753 };
 754 MODULE_DEVICE_TABLE(usb, i2400mu_id_table);
 755
 756
 757 static
 758 struct usb_driver i2400mu_driver = {
 759         .name = KBUILD_MODNAME,
 760         .suspend = i2400mu_suspend,
 761         .resume = i2400mu_resume,
 762         .reset_resume = i2400mu_reset_resume,
 763         .probe = i2400mu_probe,
 764         .disconnect = i2400mu_disconnect,
 765         .pre_reset = i2400mu_pre_reset,
 766         .post_reset = i2400mu_post_reset,
 767         .id_table = i2400mu_id_table,
 768         .supports_autosuspend = 1,
 769 };
 770
 771 static
 772 int __init i2400mu_driver_init(void)
 773 {
 774         d_parse_params(D_LEVEL, D_LEVEL_SIZE, i2400mu_debug_params,
 775                        "i2400m_usb.debug");
 776         return usb_register(&i2400mu_driver);
 777 }
 778 module_init(i2400mu_driver_init);
 779
 780
 781 static
 782 void __exit i2400mu_driver_exit(void)
 783 {
 784         usb_deregister(&i2400mu_driver);
 785 }
 786 module_exit(i2400mu_driver_exit);
 787
 788 MODULE_AUTHOR("Intel Corporation <linux-wimax@intel.com>");
 789 MODULE_DESCRIPTION("Driver for USB based Intel Wireless WiMAX Connection 2400M "
 790                    "(5x50 & 6050)");
 791 MODULE_LICENSE("GPL");
 792 MODULE_FIRMWARE(I2400MU_FW_FILE_NAME_v1_5);
 793 MODULE_FIRMWARE(I6050U_FW_FILE_NAME_v1_5);