drivers/platform/mellanox/mlxreg-hotplug.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Mellanox hotplug driver
   4  *
   5  * Copyright (C) 2016-2020 Mellanox Technologies
   6  */
   7
   8 #include <linux/bitops.h>
   9 #include <linux/device.h>
  10 #include <linux/hwmon.h>
  11 #include <linux/hwmon-sysfs.h>
  12 #include <linux/i2c.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/module.h>
  15 #include <linux/of_device.h>
  16 #include <linux/platform_data/mlxreg.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/spinlock.h>
  19 #include <linux/string_helpers.h>
  20 #include <linux/regmap.h>
  21 #include <linux/workqueue.h>
  22
  23 /* Offset of event and mask registers from status register. */
  24 #define MLXREG_HOTPLUG_EVENT_OFF        1
  25 #define MLXREG_HOTPLUG_MASK_OFF         2
  26 #define MLXREG_HOTPLUG_AGGR_MASK_OFF    1
  27
  28 /* ASIC good health mask. */
  29 #define MLXREG_HOTPLUG_GOOD_HEALTH_MASK 0x02
  30
  31 #define MLXREG_HOTPLUG_ATTRS_MAX        24
  32 #define MLXREG_HOTPLUG_NOT_ASSERT       3
  33
  34 /**
  35  * struct mlxreg_hotplug_priv_data - platform private data:
  36  * @irq: platform device interrupt number;
  37  * @dev: basic device;
  38  * @pdev: platform device;
  39  * @plat: platform data;
  40  * @regmap: register map handle;
  41  * @dwork_irq: delayed work template;
  42  * @lock: spin lock;
  43  * @hwmon: hwmon device;
  44  * @mlxreg_hotplug_attr: sysfs attributes array;
  45  * @mlxreg_hotplug_dev_attr: sysfs sensor device attribute array;
  46  * @group: sysfs attribute group;
  47  * @groups: list of sysfs attribute group for hwmon registration;
  48  * @cell: location of top aggregation interrupt register;
  49  * @mask: top aggregation interrupt common mask;
  50  * @aggr_cache: last value of aggregation register status;
  51  * @after_probe: flag indication probing completion;
  52  * @not_asserted: number of entries in workqueue with no signal assertion;
  53  */
  54 struct mlxreg_hotplug_priv_data {
  55         int irq;
  56         struct device *dev;
  57         struct platform_device *pdev;
  58         struct mlxreg_hotplug_platform_data *plat;
  59         struct regmap *regmap;
  60         struct delayed_work dwork_irq;
  61         spinlock_t lock; /* sync with interrupt */
  62         struct device *hwmon;
  63         struct attribute *mlxreg_hotplug_attr[MLXREG_HOTPLUG_ATTRS_MAX + 1];
  64         struct sensor_device_attribute_2
  65                         mlxreg_hotplug_dev_attr[MLXREG_HOTPLUG_ATTRS_MAX];
  66         struct attribute_group group;
  67         const struct attribute_group *groups[2];
  68         u32 cell;
  69         u32 mask;
  70         u32 aggr_cache;
  71         bool after_probe;
  72         u8 not_asserted;
  73 };
  74
  75 /* Environment variables array for udev. */
  76 static char *mlxreg_hotplug_udev_envp[] = { NULL, NULL };
  77
  78 static int
  79 mlxreg_hotplug_udev_event_send(struct kobject *kobj,
  80                                struct mlxreg_core_data *data, bool action)
  81 {
  82         char event_str[MLXREG_CORE_LABEL_MAX_SIZE + 2];
  83         char label[MLXREG_CORE_LABEL_MAX_SIZE] = { 0 };
  84
  85         mlxreg_hotplug_udev_envp[0] = event_str;
  86         string_upper(label, data->label);
  87         snprintf(event_str, MLXREG_CORE_LABEL_MAX_SIZE, "%s=%d", label, !!action);
  88
  89         return kobject_uevent_env(kobj, KOBJ_CHANGE, mlxreg_hotplug_udev_envp);
  90 }
  91
  92 static int mlxreg_hotplug_device_create(struct mlxreg_hotplug_priv_data *priv,
  93                                         struct mlxreg_core_data *data)
  94 {
  95         struct mlxreg_core_hotplug_platform_data *pdata;
  96         struct i2c_client *client;
  97
  98         /* Notify user by sending hwmon uevent. */
  99         mlxreg_hotplug_udev_event_send(&priv->hwmon->kobj, data, true);
 100
 101         /*
 102          * Return if adapter number is negative. It could be in case hotplug
 103          * event is not associated with hotplug device.
 104          */
 105         if (data->hpdev.nr < 0)
 106                 return 0;
 107
 108         pdata = dev_get_platdata(&priv->pdev->dev);
 109         data->hpdev.adapter = i2c_get_adapter(data->hpdev.nr +
 110                                               pdata->shift_nr);
 111         if (!data->hpdev.adapter) {
 112                 dev_err(priv->dev, "Failed to get adapter for bus %d\n",
 113                         data->hpdev.nr + pdata->shift_nr);
 114                 return -EFAULT;
 115         }
 116
 117         client = i2c_new_client_device(data->hpdev.adapter,
 118                                        data->hpdev.brdinfo);
 119         if (IS_ERR(client)) {
 120                 dev_err(priv->dev, "Failed to create client %s at bus %d at addr 0x%02x\n",
 121                         data->hpdev.brdinfo->type, data->hpdev.nr +
 122                         pdata->shift_nr, data->hpdev.brdinfo->addr);
 123
 124                 i2c_put_adapter(data->hpdev.adapter);
 125                 data->hpdev.adapter = NULL;
 126                 return PTR_ERR(client);
 127         }
 128
 129         data->hpdev.client = client;
 130
 131         return 0;
 132 }
 133
 134 static void
 135 mlxreg_hotplug_device_destroy(struct mlxreg_hotplug_priv_data *priv,
 136                               struct mlxreg_core_data *data)
 137 {
 138         /* Notify user by sending hwmon uevent. */
 139         mlxreg_hotplug_udev_event_send(&priv->hwmon->kobj, data, false);
 140
 141         if (data->hpdev.client) {
 142                 i2c_unregister_device(data->hpdev.client);
 143                 data->hpdev.client = NULL;
 144         }
 145
 146         if (data->hpdev.adapter) {
 147                 i2c_put_adapter(data->hpdev.adapter);
 148                 data->hpdev.adapter = NULL;
 149         }
 150 }
 151
 152 static ssize_t mlxreg_hotplug_attr_show(struct device *dev,
 153                                         struct device_attribute *attr,
 154                                         char *buf)
 155 {
 156         struct mlxreg_hotplug_priv_data *priv = dev_get_drvdata(dev);
 157         struct mlxreg_core_hotplug_platform_data *pdata;
 158         int index = to_sensor_dev_attr_2(attr)->index;
 159         int nr = to_sensor_dev_attr_2(attr)->nr;
 160         struct mlxreg_core_item *item;
 161         struct mlxreg_core_data *data;
 162         u32 regval;
 163         int ret;
 164
 165         pdata = dev_get_platdata(&priv->pdev->dev);
 166         item = pdata->items + nr;
 167         data = item->data + index;
 168
 169         ret = regmap_read(priv->regmap, data->reg, &regval);
 170         if (ret)
 171                 return ret;
 172
 173         if (item->health) {
 174                 regval &= data->mask;
 175         } else {
 176                 /* Bit = 0 : functional if item->inversed is true. */
 177                 if (item->inversed)
 178                         regval = !(regval & data->mask);
 179                 else
 180                         regval = !!(regval & data->mask);
 181         }
 182
 183         return sprintf(buf, "%u\n", regval);
 184 }
 185
 186 #define PRIV_ATTR(i) priv->mlxreg_hotplug_attr[i]
 187 #define PRIV_DEV_ATTR(i) priv->mlxreg_hotplug_dev_attr[i]
 188
 189 static int mlxreg_hotplug_attr_init(struct mlxreg_hotplug_priv_data *priv)
 190 {
 191         struct mlxreg_core_hotplug_platform_data *pdata;
 192         struct mlxreg_core_item *item;
 193         struct mlxreg_core_data *data;
 194         unsigned long mask;
 195         u32 regval;
 196         int num_attrs = 0, id = 0, i, j, k, ret;
 197
 198         pdata = dev_get_platdata(&priv->pdev->dev);
 199         item = pdata->items;
 200
 201         /* Go over all kinds of items - psu, pwr, fan. */
 202         for (i = 0; i < pdata->counter; i++, item++) {
 203                 if (item->capability) {
 204                         /*
 205                          * Read group capability register to get actual number
 206                          * of interrupt capable components and set group mask
 207                          * accordingly.
 208                          */
 209                         ret = regmap_read(priv->regmap, item->capability,
 210                                           &regval);
 211                         if (ret)
 212                                 return ret;
 213
 214                         item->mask = GENMASK((regval & item->mask) - 1, 0);
 215                 }
 216
 217                 data = item->data;
 218
 219                 /* Go over all unmasked units within item. */
 220                 mask = item->mask;
 221                 k = 0;
 222                 for_each_set_bit(j, &mask, item->count) {
 223                         if (data->capability) {
 224                                 /*
 225                                  * Read capability register and skip non
 226                                  * relevant attributes.
 227                                  */
 228                                 ret = regmap_read(priv->regmap,
 229                                                   data->capability, &regval);
 230                                 if (ret)
 231                                         return ret;
 232                                 if (!(regval & data->bit)) {
 233                                         data++;
 234                                         continue;
 235                                 }
 236                         }
 237                         PRIV_ATTR(id) = &PRIV_DEV_ATTR(id).dev_attr.attr;
 238                         PRIV_ATTR(id)->name = devm_kasprintf(&priv->pdev->dev,
 239                                                              GFP_KERNEL,
 240                                                              data->label);
 241
 242                         if (!PRIV_ATTR(id)->name) {
 243                                 dev_err(priv->dev, "Memory allocation failed for attr %d.\n",
 244                                         id);
 245                                 return -ENOMEM;
 246                         }
 247
 248                         PRIV_DEV_ATTR(id).dev_attr.attr.name =
 249                                                         PRIV_ATTR(id)->name;
 250                         PRIV_DEV_ATTR(id).dev_attr.attr.mode = 0444;
 251                         PRIV_DEV_ATTR(id).dev_attr.show =
 252                                                 mlxreg_hotplug_attr_show;
 253                         PRIV_DEV_ATTR(id).nr = i;
 254                         PRIV_DEV_ATTR(id).index = k;
 255                         sysfs_attr_init(&PRIV_DEV_ATTR(id).dev_attr.attr);
 256                         data++;
 257                         id++;
 258                         k++;
 259                 }
 260                 num_attrs += k;
 261         }
 262
 263         priv->group.attrs = devm_kcalloc(&priv->pdev->dev,
 264                                          num_attrs,
 265                                          sizeof(struct attribute *),
 266                                          GFP_KERNEL);
 267         if (!priv->group.attrs)
 268                 return -ENOMEM;
 269
 270         priv->group.attrs = priv->mlxreg_hotplug_attr;
 271         priv->groups[0] = &priv->group;
 272         priv->groups[1] = NULL;
 273
 274         return 0;
 275 }
 276
 277 static void
 278 mlxreg_hotplug_work_helper(struct mlxreg_hotplug_priv_data *priv,
 279                            struct mlxreg_core_item *item)
 280 {
 281         struct mlxreg_core_data *data;
 282         unsigned long asserted;
 283         u32 regval, bit;
 284         int ret;
 285
 286         /*
 287          * Validate if item related to received signal type is valid.
 288          * It should never happen, excepted the situation when some
 289          * piece of hardware is broken. In such situation just produce
 290          * error message and return. Caller must continue to handle the
 291          * signals from other devices if any.
 292          */
 293         if (unlikely(!item)) {
 294                 dev_err(priv->dev, "False signal: at offset:mask 0x%02x:0x%02x.\n",
 295                         item->reg, item->mask);
 296
 297                 return;
 298         }
 299
 300         /* Mask event. */
 301         ret = regmap_write(priv->regmap, item->reg + MLXREG_HOTPLUG_MASK_OFF,
 302                            0);
 303         if (ret)
 304                 goto out;
 305
 306         /* Read status. */
 307         ret = regmap_read(priv->regmap, item->reg, &regval);
 308         if (ret)
 309                 goto out;
 310
 311         /* Set asserted bits and save last status. */
 312         regval &= item->mask;
 313         asserted = item->cache ^ regval;
 314         item->cache = regval;
 315
 316         for_each_set_bit(bit, &asserted, 8) {
 317                 data = item->data + bit;
 318                 if (regval & BIT(bit)) {
 319                         if (item->inversed)
 320                                 mlxreg_hotplug_device_destroy(priv, data);
 321                         else
 322                                 mlxreg_hotplug_device_create(priv, data);
 323                 } else {
 324                         if (item->inversed)
 325                                 mlxreg_hotplug_device_create(priv, data);
 326                         else
 327                                 mlxreg_hotplug_device_destroy(priv, data);
 328                 }
 329         }
 330
 331         /* Acknowledge event. */
 332         ret = regmap_write(priv->regmap, item->reg + MLXREG_HOTPLUG_EVENT_OFF,
 333                            0);
 334         if (ret)
 335                 goto out;
 336
 337         /* Unmask event. */
 338         ret = regmap_write(priv->regmap, item->reg + MLXREG_HOTPLUG_MASK_OFF,
 339                            item->mask);
 340
 341  out:
 342         if (ret)
 343                 dev_err(priv->dev, "Failed to complete workqueue.\n");
 344 }
 345
 346 static void
 347 mlxreg_hotplug_health_work_helper(struct mlxreg_hotplug_priv_data *priv,
 348                                   struct mlxreg_core_item *item)
 349 {
 350         struct mlxreg_core_data *data = item->data;
 351         u32 regval;
 352         int i, ret = 0;
 353
 354         for (i = 0; i < item->count; i++, data++) {
 355                 /* Mask event. */
 356                 ret = regmap_write(priv->regmap, data->reg +
 357                                    MLXREG_HOTPLUG_MASK_OFF, 0);
 358                 if (ret)
 359                         goto out;
 360
 361                 /* Read status. */
 362                 ret = regmap_read(priv->regmap, data->reg, &regval);
 363                 if (ret)
 364                         goto out;
 365
 366                 regval &= data->mask;
 367
 368                 if (item->cache == regval)
 369                         goto ack_event;
 370
 371                 /*
 372                  * ASIC health indication is provided through two bits. Bits
 373                  * value 0x2 indicates that ASIC reached the good health, value
 374                  * 0x0 indicates ASIC the bad health or dormant state and value
 375                  * 0x3 indicates the booting state. During ASIC reset it should
 376                  * pass the following states: dormant -> booting -> good.
 377                  */
 378                 if (regval == MLXREG_HOTPLUG_GOOD_HEALTH_MASK) {
 379                         if (!data->attached) {
 380                                 /*
 381                                  * ASIC is in steady state. Connect associated
 382                                  * device, if configured.
 383                                  */
 384                                 mlxreg_hotplug_device_create(priv, data);
 385                                 data->attached = true;
 386                         }
 387                 } else {
 388                         if (data->attached) {
 389                                 /*
 390                                  * ASIC health is failed after ASIC has been
 391                                  * in steady state. Disconnect associated
 392                                  * device, if it has been connected.
 393                                  */
 394                                 mlxreg_hotplug_device_destroy(priv, data);
 395                                 data->attached = false;
 396                                 data->health_cntr = 0;
 397                         }
 398                 }
 399                 item->cache = regval;
 400 ack_event:
 401                 /* Acknowledge event. */
 402                 ret = regmap_write(priv->regmap, data->reg +
 403                                    MLXREG_HOTPLUG_EVENT_OFF, 0);
 404                 if (ret)
 405                         goto out;
 406
 407                 /* Unmask event. */
 408                 ret = regmap_write(priv->regmap, data->reg +
 409                                    MLXREG_HOTPLUG_MASK_OFF, data->mask);
 410                 if (ret)
 411                         goto out;
 412         }
 413
 414  out:
 415         if (ret)
 416                 dev_err(priv->dev, "Failed to complete workqueue.\n");
 417 }
 418
 419 /*
 420  * mlxreg_hotplug_work_handler - performs traversing of device interrupt
 421  * registers according to the below hierarchy schema:
 422  *
 423  *                              Aggregation registers (status/mask)
 424  * PSU registers:               *---*
 425  * *-----------------*          |   |
 426  * |status/event/mask|----->    | * |
 427  * *-----------------*          |   |
 428  * Power registers:             |   |
 429  * *-----------------*          |   |
 430  * |status/event/mask|----->    | * |
 431  * *-----------------*          |   |
 432  * FAN registers:               |   |--> CPU
 433  * *-----------------*          |   |
 434  * |status/event/mask|----->    | * |
 435  * *-----------------*          |   |
 436  * ASIC registers:              |   |
 437  * *-----------------*          |   |
 438  * |status/event/mask|----->    | * |
 439  * *-----------------*          |   |
 440  *                              *---*
 441  *
 442  * In case some system changed are detected: FAN in/out, PSU in/out, power
 443  * cable attached/detached, ASIC health good/bad, relevant device is created
 444  * or destroyed.
 445  */
 446 static void mlxreg_hotplug_work_handler(struct work_struct *work)
 447 {
 448         struct mlxreg_core_hotplug_platform_data *pdata;
 449         struct mlxreg_hotplug_priv_data *priv;
 450         struct mlxreg_core_item *item;
 451         u32 regval, aggr_asserted;
 452         unsigned long flags;
 453         int i, ret;
 454
 455         priv = container_of(work, struct mlxreg_hotplug_priv_data,
 456                             dwork_irq.work);
 457         pdata = dev_get_platdata(&priv->pdev->dev);
 458         item = pdata->items;
 459
 460         /* Mask aggregation event. */
 461         ret = regmap_write(priv->regmap, pdata->cell +
 462                            MLXREG_HOTPLUG_AGGR_MASK_OFF, 0);
 463         if (ret < 0)
 464                 goto out;
 465
 466         /* Read aggregation status. */
 467         ret = regmap_read(priv->regmap, pdata->cell, &regval);
 468         if (ret)
 469                 goto out;
 470
 471         regval &= pdata->mask;
 472         aggr_asserted = priv->aggr_cache ^ regval;
 473         priv->aggr_cache = regval;
 474
 475         /*
 476          * Handler is invoked, but no assertion is detected at top aggregation
 477          * status level. Set aggr_asserted to mask value to allow handler extra
 478          * run over all relevant signals to recover any missed signal.
 479          */
 480         if (priv->not_asserted == MLXREG_HOTPLUG_NOT_ASSERT) {
 481                 priv->not_asserted = 0;
 482                 aggr_asserted = pdata->mask;
 483         }
 484         if (!aggr_asserted)
 485                 goto unmask_event;
 486
 487         /* Handle topology and health configuration changes. */
 488         for (i = 0; i < pdata->counter; i++, item++) {
 489                 if (aggr_asserted & item->aggr_mask) {
 490                         if (item->health)
 491                                 mlxreg_hotplug_health_work_helper(priv, item);
 492                         else
 493                                 mlxreg_hotplug_work_helper(priv, item);
 494                 }
 495         }
 496
 497         spin_lock_irqsave(&priv->lock, flags);
 498
 499         /*
 500          * It is possible, that some signals have been inserted, while
 501          * interrupt has been masked by mlxreg_hotplug_work_handler. In this
 502          * case such signals will be missed. In order to handle these signals
 503          * delayed work is canceled and work task re-scheduled for immediate
 504          * execution. It allows to handle missed signals, if any. In other case
 505          * work handler just validates that no new signals have been received
 506          * during masking.
 507          */
 508         cancel_delayed_work(&priv->dwork_irq);
 509         schedule_delayed_work(&priv->dwork_irq, 0);
 510
 511         spin_unlock_irqrestore(&priv->lock, flags);
 512
 513         return;
 514
 515 unmask_event:
 516         priv->not_asserted++;
 517         /* Unmask aggregation event (no need acknowledge). */
 518         ret = regmap_write(priv->regmap, pdata->cell +
 519                            MLXREG_HOTPLUG_AGGR_MASK_OFF, pdata->mask);
 520
 521  out:
 522         if (ret)
 523                 dev_err(priv->dev, "Failed to complete workqueue.\n");
 524 }
 525
 526 static int mlxreg_hotplug_set_irq(struct mlxreg_hotplug_priv_data *priv)
 527 {
 528         struct mlxreg_core_hotplug_platform_data *pdata;
 529         struct mlxreg_core_item *item;
 530         struct mlxreg_core_data *data;
 531         u32 regval;
 532         int i, j, ret;
 533
 534         pdata = dev_get_platdata(&priv->pdev->dev);
 535         item = pdata->items;
 536
 537         for (i = 0; i < pdata->counter; i++, item++) {
 538                 /* Clear group presense event. */
 539                 ret = regmap_write(priv->regmap, item->reg +
 540                                    MLXREG_HOTPLUG_EVENT_OFF, 0);
 541                 if (ret)
 542                         goto out;
 543
 544                 /*
 545                  * Verify if hardware configuration requires to disable
 546                  * interrupt capability for some of components.
 547                  */
 548                 data = item->data;
 549                 for (j = 0; j < item->count; j++, data++) {
 550                         /* Verify if the attribute has capability register. */
 551                         if (data->capability) {
 552                                 /* Read capability register. */
 553                                 ret = regmap_read(priv->regmap,
 554                                                   data->capability, &regval);
 555                                 if (ret)
 556                                         goto out;
 557
 558                                 if (!(regval & data->bit))
 559                                         item->mask &= ~BIT(j);
 560                         }
 561                 }
 562
 563                 /* Set group initial status as mask and unmask group event. */
 564                 if (item->inversed) {
 565                         item->cache = item->mask;
 566                         ret = regmap_write(priv->regmap, item->reg +
 567                                            MLXREG_HOTPLUG_MASK_OFF,
 568                                            item->mask);
 569                         if (ret)
 570                                 goto out;
 571                 }
 572         }
 573
 574         /* Keep aggregation initial status as zero and unmask events. */
 575         ret = regmap_write(priv->regmap, pdata->cell +
 576                            MLXREG_HOTPLUG_AGGR_MASK_OFF, pdata->mask);
 577         if (ret)
 578                 goto out;
 579
 580         /* Keep low aggregation initial status as zero and unmask events. */
 581         if (pdata->cell_low) {
 582                 ret = regmap_write(priv->regmap, pdata->cell_low +
 583                                    MLXREG_HOTPLUG_AGGR_MASK_OFF,
 584                                    pdata->mask_low);
 585                 if (ret)
 586                         goto out;
 587         }
 588
 589         /* Invoke work handler for initializing hot plug devices setting. */
 590         mlxreg_hotplug_work_handler(&priv->dwork_irq.work);
 591
 592  out:
 593         if (ret)
 594                 dev_err(priv->dev, "Failed to set interrupts.\n");
 595         enable_irq(priv->irq);
 596         return ret;
 597 }
 598
 599 static void mlxreg_hotplug_unset_irq(struct mlxreg_hotplug_priv_data *priv)
 600 {
 601         struct mlxreg_core_hotplug_platform_data *pdata;
 602         struct mlxreg_core_item *item;
 603         struct mlxreg_core_data *data;
 604         int count, i, j;
 605
 606         pdata = dev_get_platdata(&priv->pdev->dev);
 607         item = pdata->items;
 608         disable_irq(priv->irq);
 609         cancel_delayed_work_sync(&priv->dwork_irq);
 610
 611         /* Mask low aggregation event, if defined. */
 612         if (pdata->cell_low)
 613                 regmap_write(priv->regmap, pdata->cell_low +
 614                              MLXREG_HOTPLUG_AGGR_MASK_OFF, 0);
 615
 616         /* Mask aggregation event. */
 617         regmap_write(priv->regmap, pdata->cell + MLXREG_HOTPLUG_AGGR_MASK_OFF,
 618                      0);
 619
 620         /* Clear topology configurations. */
 621         for (i = 0; i < pdata->counter; i++, item++) {
 622                 data = item->data;
 623                 /* Mask group presense event. */
 624                 regmap_write(priv->regmap, data->reg + MLXREG_HOTPLUG_MASK_OFF,
 625                              0);
 626                 /* Clear group presense event. */
 627                 regmap_write(priv->regmap, data->reg +
 628                              MLXREG_HOTPLUG_EVENT_OFF, 0);
 629
 630                 /* Remove all the attached devices in group. */
 631                 count = item->count;
 632                 for (j = 0; j < count; j++, data++)
 633                         mlxreg_hotplug_device_destroy(priv, data);
 634         }
 635 }
 636
 637 static irqreturn_t mlxreg_hotplug_irq_handler(int irq, void *dev)
 638 {
 639         struct mlxreg_hotplug_priv_data *priv;
 640
 641         priv = (struct mlxreg_hotplug_priv_data *)dev;
 642
 643         /* Schedule work task for immediate execution.*/
 644         schedule_delayed_work(&priv->dwork_irq, 0);
 645
 646         return IRQ_HANDLED;
 647 }
 648
 649 static int mlxreg_hotplug_probe(struct platform_device *pdev)
 650 {
 651         struct mlxreg_core_hotplug_platform_data *pdata;
 652         struct mlxreg_hotplug_priv_data *priv;
 653         struct i2c_adapter *deferred_adap;
 654         int err;
 655
 656         pdata = dev_get_platdata(&pdev->dev);
 657         if (!pdata) {
 658                 dev_err(&pdev->dev, "Failed to get platform data.\n");
 659                 return -EINVAL;
 660         }
 661
 662         /* Defer probing if the necessary adapter is not configured yet. */
 663         deferred_adap = i2c_get_adapter(pdata->deferred_nr);
 664         if (!deferred_adap)
 665                 return -EPROBE_DEFER;
 666         i2c_put_adapter(deferred_adap);
 667
 668         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 669         if (!priv)
 670                 return -ENOMEM;
 671
 672         if (pdata->irq) {
 673                 priv->irq = pdata->irq;
 674         } else {
 675                 priv->irq = platform_get_irq(pdev, 0);
 676                 if (priv->irq < 0)
 677                         return priv->irq;
 678         }
 679
 680         priv->regmap = pdata->regmap;
 681         priv->dev = pdev->dev.parent;
 682         priv->pdev = pdev;
 683
 684         err = devm_request_irq(&pdev->dev, priv->irq,
 685                                mlxreg_hotplug_irq_handler, IRQF_TRIGGER_FALLING
 686                                | IRQF_SHARED, "mlxreg-hotplug", priv);
 687         if (err) {
 688                 dev_err(&pdev->dev, "Failed to request irq: %d\n", err);
 689                 return err;
 690         }
 691
 692         disable_irq(priv->irq);
 693         spin_lock_init(&priv->lock);
 694         INIT_DELAYED_WORK(&priv->dwork_irq, mlxreg_hotplug_work_handler);
 695         dev_set_drvdata(&pdev->dev, priv);
 696
 697         err = mlxreg_hotplug_attr_init(priv);
 698         if (err) {
 699                 dev_err(&pdev->dev, "Failed to allocate attributes: %d\n",
 700                         err);
 701                 return err;
 702         }
 703
 704         priv->hwmon = devm_hwmon_device_register_with_groups(&pdev->dev,
 705                                         "mlxreg_hotplug", priv, priv->groups);
 706         if (IS_ERR(priv->hwmon)) {
 707                 dev_err(&pdev->dev, "Failed to register hwmon device %ld\n",
 708                         PTR_ERR(priv->hwmon));
 709                 return PTR_ERR(priv->hwmon);
 710         }
 711
 712         /* Perform initial interrupts setup. */
 713         mlxreg_hotplug_set_irq(priv);
 714         priv->after_probe = true;
 715
 716         return 0;
 717 }
 718
 719 static int mlxreg_hotplug_remove(struct platform_device *pdev)
 720 {
 721         struct mlxreg_hotplug_priv_data *priv = dev_get_drvdata(&pdev->dev);
 722
 723         /* Clean interrupts setup. */
 724         mlxreg_hotplug_unset_irq(priv);
 725         devm_free_irq(&pdev->dev, priv->irq, priv);
 726
 727         return 0;
 728 }
 729
 730 static struct platform_driver mlxreg_hotplug_driver = {
 731         .driver = {
 732                 .name = "mlxreg-hotplug",
 733         },
 734         .probe = mlxreg_hotplug_probe,
 735         .remove = mlxreg_hotplug_remove,
 736 };
 737
 738 module_platform_driver(mlxreg_hotplug_driver);
 739
 740 MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
 741 MODULE_DESCRIPTION("Mellanox regmap hotplug platform driver");
 742 MODULE_LICENSE("Dual BSD/GPL");
 743 MODULE_ALIAS("platform:mlxreg-hotplug");