Quelle  hid-sensor-hub.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * HID Sensors Driver
 * Copyright (c) 2012, Intel Corporation.
 */

#include <linux/device.h>
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mfd/core.h>
#include <linux/list.h>
#include <linux/hid-sensor-ids.h>
#include <linux/hid-sensor-hub.h>
#include "hid-ids.h"

#define HID_SENSOR_HUB_ENUM_QUIRK 0x01

/**
 * struct sensor_hub_data - Hold a instance data for a HID hub device
 * @mutex: Mutex to serialize synchronous request.
 * @lock: Spin lock to protect pending request structure.
 * @dyn_callback_list: Holds callback function
 * @dyn_callback_lock: spin lock to protect callback list
 * @hid_sensor_hub_client_devs: Stores all MFD cells for a hub instance.
 * @hid_sensor_client_cnt: Number of MFD cells, (no of sensors attached).
 * @ref_cnt: Number of MFD clients have opened this device
 */
struct sensor_hub_data {
 struct mutex mutex;
 spinlock_t lock;
 struct list_head dyn_callback_list;
 spinlock_t dyn_callback_lock;
 struct mfd_cell *hid_sensor_hub_client_devs;
 int hid_sensor_client_cnt;
 int ref_cnt;
};

/**
 * struct hid_sensor_hub_callbacks_list - Stores callback list
 * @list: list head.
 * @usage_id: usage id for a physical device.
 * @hsdev: Stored hid instance for current hub device.
 * @usage_callback: Stores registered callback functions.
 * @priv: Private data for a physical device.
 */
struct hid_sensor_hub_callbacks_list {
 struct list_head list;
 u32 usage_id;
 struct hid_sensor_hub_device *hsdev;
 struct hid_sensor_hub_callbacks *usage_callback;
 void *priv;
};

static struct hid_report *sensor_hub_report(int id, struct hid_device *hdev,
      int dir)
{
 struct hid_report *report;

 list_for_each_entry(report, &hdev->report_enum[dir].report_list, list) {
  if (report->id == id)
   return report;
 }
 hid_warn(hdev, "No report with id 0x%x found\n", id);

 return NULL;
}

static int sensor_hub_get_physical_device_count(struct hid_device *hdev)
{
 int i;
 int count = 0;

 for (i = 0; i < hdev->maxcollection; ++i) {
  struct hid_collection *collection = &hdev->collection[i];
  if (collection->type == HID_COLLECTION_PHYSICAL ||
      collection->type == HID_COLLECTION_APPLICATION)
   ++count;
 }

 return count;
}

static void sensor_hub_fill_attr_info(
  struct hid_sensor_hub_attribute_info *info,
  s32 index, s32 report_id, struct hid_field *field)
{
 info->index = index;
 info->report_id = report_id;
 info->units = field->unit;
 info->unit_expo = field->unit_exponent;
 info->size = (field->report_size * field->report_count)/8;
 info->logical_minimum = field->logical_minimum;
 info->logical_maximum = field->logical_maximum;
}

static struct hid_sensor_hub_callbacks *sensor_hub_get_callback(
     struct hid_device *hdev,
     u32 usage_id,
     int collection_index,
     struct hid_sensor_hub_device **hsdev,
     void **priv)
{
 struct hid_sensor_hub_callbacks_list *callback;
 struct sensor_hub_data *pdata = hid_get_drvdata(hdev);
 unsigned long flags;

 spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
 list_for_each_entry(callback, &pdata->dyn_callback_list, list)
  if ((callback->usage_id == usage_id ||
       callback->usage_id == HID_USAGE_SENSOR_COLLECTION) &&
   (collection_index >=
    callback->hsdev->start_collection_index) &&
   (collection_index <
    callback->hsdev->end_collection_index)) {
   *priv = callback->priv;
   *hsdev = callback->hsdev;
   spin_unlock_irqrestore(&pdata->dyn_callback_lock,
            flags);
   return callback->usage_callback;
  }
 spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);

 return NULL;
}

int sensor_hub_register_callback(struct hid_sensor_hub_device *hsdev,
   u32 usage_id,
   struct hid_sensor_hub_callbacks *usage_callback)
{
 struct hid_sensor_hub_callbacks_list *callback;
 struct sensor_hub_data *pdata = hid_get_drvdata(hsdev->hdev);
 unsigned long flags;

 spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
 list_for_each_entry(callback, &pdata->dyn_callback_list, list)
  if (callback->usage_id == usage_id &&
      callback->hsdev == hsdev) {
   spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
   return -EINVAL;
  }
 callback = kzalloc(sizeof(*callback), GFP_ATOMIC);
 if (!callback) {
  spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
  return -ENOMEM;
 }
 callback->hsdev = hsdev;
 callback->usage_callback = usage_callback;
 callback->usage_id = usage_id;
 callback->priv = NULL;
 /*
 * If there is a handler registered for the collection type, then
 * it will handle all reports for sensors in this collection. If
 * there is also an individual sensor handler registration, then
 * we want to make sure that the reports are directed to collection
 * handler, as this may be a fusion sensor. So add collection handlers
 * to the beginning of the list, so that they are matched first.
 */
 if (usage_id == HID_USAGE_SENSOR_COLLECTION)
  list_add(&callback->list, &pdata->dyn_callback_list);
 else
  list_add_tail(&callback->list, &pdata->dyn_callback_list);
 spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);

 return 0;
}
EXPORT_SYMBOL_GPL(sensor_hub_register_callback);

int sensor_hub_remove_callback(struct hid_sensor_hub_device *hsdev,
    u32 usage_id)
{
 struct hid_sensor_hub_callbacks_list *callback;
 struct sensor_hub_data *pdata = hid_get_drvdata(hsdev->hdev);
 unsigned long flags;

 spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
 list_for_each_entry(callback, &pdata->dyn_callback_list, list)
  if (callback->usage_id == usage_id &&
      callback->hsdev == hsdev) {
   list_del(&callback->list);
   kfree(callback);
   break;
  }
 spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);

 return 0;
}
EXPORT_SYMBOL_GPL(sensor_hub_remove_callback);

int sensor_hub_set_feature(struct hid_sensor_hub_device *hsdev, u32 report_id,
      u32 field_index, int buffer_size, void *buffer)
{
 struct hid_report *report;
 struct sensor_hub_data *data = hid_get_drvdata(hsdev->hdev);
 __s32 *buf32 = buffer;
 int i = 0;
 int remaining_bytes;
 __s32 value;
 int ret = 0;

 mutex_lock(&data->mutex);
 report = sensor_hub_report(report_id, hsdev->hdev, HID_FEATURE_REPORT);
 if (!report || (field_index >= report->maxfield)) {
  ret = -EINVAL;
  goto done_proc;
 }

 remaining_bytes = buffer_size % sizeof(__s32);
 buffer_size = buffer_size / sizeof(__s32);
 if (buffer_size) {
  for (i = 0; i < buffer_size; ++i) {
   ret = hid_set_field(report->field[field_index], i,
         (__force __s32)cpu_to_le32(*buf32));
   if (ret)
    goto done_proc;

   ++buf32;
  }
 }
 if (remaining_bytes) {
  value = 0;
  memcpy(&value, (u8 *)buf32, remaining_bytes);
  ret = hid_set_field(report->field[field_index], i,
        (__force __s32)cpu_to_le32(value));
  if (ret)
   goto done_proc;
 }
 hid_hw_request(hsdev->hdev, report, HID_REQ_SET_REPORT);
 hid_hw_wait(hsdev->hdev);

done_proc:
 mutex_unlock(&data->mutex);

 return ret;
}
EXPORT_SYMBOL_GPL(sensor_hub_set_feature);

int sensor_hub_get_feature(struct hid_sensor_hub_device *hsdev, u32 report_id,
      u32 field_index, int buffer_size, void *buffer)
{
 struct hid_report *report;
 struct sensor_hub_data *data = hid_get_drvdata(hsdev->hdev);
 int report_size;
 int ret = 0;
 u8 *val_ptr;
 int buffer_index = 0;
 int i;

 memset(buffer, 0, buffer_size);

 mutex_lock(&data->mutex);
 report = sensor_hub_report(report_id, hsdev->hdev, HID_FEATURE_REPORT);
 if (!report || (field_index >= report->maxfield) ||
     report->field[field_index]->report_count < 1) {
  ret = -EINVAL;
  goto done_proc;
 }
 hid_hw_request(hsdev->hdev, report, HID_REQ_GET_REPORT);
 hid_hw_wait(hsdev->hdev);

 /* calculate number of bytes required to read this field */
 report_size = DIV_ROUND_UP(report->field[field_index]->report_size,
       8) *
       report->field[field_index]->report_count;
 if (!report_size) {
  ret = -EINVAL;
  goto done_proc;
 }
 ret = min(report_size, buffer_size);

 val_ptr = (u8 *)report->field[field_index]->value;
 for (i = 0; i < report->field[field_index]->report_count; ++i) {
  if (buffer_index >= ret)
   break;

  memcpy(&((u8 *)buffer)[buffer_index], val_ptr,
         report->field[field_index]->report_size / 8);
  val_ptr += sizeof(__s32);
  buffer_index += (report->field[field_index]->report_size / 8);
 }

done_proc:
 mutex_unlock(&data->mutex);

 return ret;
}
EXPORT_SYMBOL_GPL(sensor_hub_get_feature);


int sensor_hub_input_attr_get_raw_value(struct hid_sensor_hub_device *hsdev,
     u32 usage_id,
     u32 attr_usage_id, u32 report_id,
     enum sensor_hub_read_flags flag,
     bool is_signed)
{
 struct sensor_hub_data *data = hid_get_drvdata(hsdev->hdev);
 unsigned long flags;
 struct hid_report *report;
 int ret_val = 0;

 report = sensor_hub_report(report_id, hsdev->hdev,
       HID_INPUT_REPORT);
 if (!report)
  return -EINVAL;

 mutex_lock(hsdev->mutex_ptr);
 if (flag == SENSOR_HUB_SYNC) {
  memset(&hsdev->pending, 0, sizeof(hsdev->pending));
  init_completion(&hsdev->pending.ready);
  hsdev->pending.usage_id = usage_id;
  hsdev->pending.attr_usage_id = attr_usage_id;
  hsdev->pending.raw_size = 0;

  spin_lock_irqsave(&data->lock, flags);
  hsdev->pending.status = true;
  spin_unlock_irqrestore(&data->lock, flags);
 }
 mutex_lock(&data->mutex);
 hid_hw_request(hsdev->hdev, report, HID_REQ_GET_REPORT);
 mutex_unlock(&data->mutex);
 if (flag == SENSOR_HUB_SYNC) {
  wait_for_completion_interruptible_timeout(
      &hsdev->pending.ready, HZ*5);
  switch (hsdev->pending.raw_size) {
  case 1:
   if (is_signed)
    ret_val = *(s8 *)hsdev->pending.raw_data;
   else
    ret_val = *(u8 *)hsdev->pending.raw_data;
   break;
  case 2:
   if (is_signed)
    ret_val = *(s16 *)hsdev->pending.raw_data;
   else
    ret_val = *(u16 *)hsdev->pending.raw_data;
   break;
  case 4:
   ret_val = *(u32 *)hsdev->pending.raw_data;
   break;
  default:
   ret_val = 0;
  }
  kfree(hsdev->pending.raw_data);
  hsdev->pending.status = false;
 }
 mutex_unlock(hsdev->mutex_ptr);

 return ret_val;
}
EXPORT_SYMBOL_GPL(sensor_hub_input_attr_get_raw_value);

int hid_sensor_get_usage_index(struct hid_sensor_hub_device *hsdev,
    u32 report_id, int field_index, u32 usage_id)
{
 struct hid_report *report;
 struct hid_field *field;
 int i;

 report = sensor_hub_report(report_id, hsdev->hdev, HID_FEATURE_REPORT);
 if (!report || (field_index >= report->maxfield))
  goto done_proc;

 field = report->field[field_index];
 for (i = 0; i < field->maxusage; ++i) {
  if (field->usage[i].hid == usage_id)
   return field->usage[i].usage_index;
 }

done_proc:
 return -EINVAL;
}
EXPORT_SYMBOL_GPL(hid_sensor_get_usage_index);

int sensor_hub_input_get_attribute_info(struct hid_sensor_hub_device *hsdev,
    u8 type,
    u32 usage_id,
    u32 attr_usage_id,
    struct hid_sensor_hub_attribute_info *info)
{
 int ret = -1;
 int i;
 struct hid_report *report;
 struct hid_field *field;
 struct hid_report_enum *report_enum;
 struct hid_device *hdev = hsdev->hdev;

 /* Initialize with defaults */
 info->usage_id = usage_id;
 info->attrib_id = attr_usage_id;
 info->report_id = -1;
 info->index = -1;
 info->units = -1;
 info->unit_expo = -1;

 report_enum = &hdev->report_enum[type];
 list_for_each_entry(report, &report_enum->report_list, list) {
  for (i = 0; i < report->maxfield; ++i) {
   field = report->field[i];
   if (field->maxusage) {
    if ((field->physical == usage_id ||
         field->application == usage_id) &&
     (field->logical == attr_usage_id ||
     field->usage[0].hid ==
       attr_usage_id) &&
     (field->usage[0].collection_index >=
     hsdev->start_collection_index) &&
     (field->usage[0].collection_index <
     hsdev->end_collection_index)) {

     sensor_hub_fill_attr_info(info, i,
        report->id,
        field);
     ret = 0;
     break;
    }
   }
  }

 }

 return ret;
}
EXPORT_SYMBOL_GPL(sensor_hub_input_get_attribute_info);

#ifdef CONFIG_PM
static int sensor_hub_suspend(struct hid_device *hdev, pm_message_t message)
{
 struct sensor_hub_data *pdata = hid_get_drvdata(hdev);
 struct hid_sensor_hub_callbacks_list *callback;
 unsigned long flags;

 hid_dbg(hdev, " sensor_hub_suspend\n");
 spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
 list_for_each_entry(callback, &pdata->dyn_callback_list, list) {
  if (callback->usage_callback->suspend)
   callback->usage_callback->suspend(
     callback->hsdev, callback->priv);
 }
 spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);

 return 0;
}

static int sensor_hub_resume(struct hid_device *hdev)
{
 struct sensor_hub_data *pdata = hid_get_drvdata(hdev);
 struct hid_sensor_hub_callbacks_list *callback;
 unsigned long flags;

 hid_dbg(hdev, " sensor_hub_resume\n");
 spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
 list_for_each_entry(callback, &pdata->dyn_callback_list, list) {
  if (callback->usage_callback->resume)
   callback->usage_callback->resume(
     callback->hsdev, callback->priv);
 }
 spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);

 return 0;
}

static int sensor_hub_reset_resume(struct hid_device *hdev)
{
 return 0;
}
#endif

/*
 * Handle raw report as sent by device
 */
static int sensor_hub_raw_event(struct hid_device *hdev,
  struct hid_report *report, u8 *raw_data, int size)
{
 int i;
 u8 *ptr;
 int sz;
 struct sensor_hub_data *pdata = hid_get_drvdata(hdev);
 unsigned long flags;
 struct hid_sensor_hub_callbacks *callback = NULL;
 struct hid_collection *collection = NULL;
 void *priv = NULL;
 struct hid_sensor_hub_device *hsdev = NULL;

 hid_dbg(hdev, "sensor_hub_raw_event report id:0x%x size:%d type:%d\n",
    report->id, size, report->type);
 hid_dbg(hdev, "maxfield:%d\n", report->maxfield);
 if (report->type != HID_INPUT_REPORT)
  return 1;

 ptr = raw_data;
 if (report->id)
  ptr++; /* Skip report id */

 spin_lock_irqsave(&pdata->lock, flags);

 for (i = 0; i < report->maxfield; ++i) {
  hid_dbg(hdev, "%d collection_index:%x hid:%x sz:%x\n",
    i, report->field[i]->usage->collection_index,
    report->field[i]->usage->hid,
    (report->field[i]->report_size *
     report->field[i]->report_count)/8);
  sz = (report->field[i]->report_size *
     report->field[i]->report_count)/8;
  collection = &hdev->collection[
    report->field[i]->usage->collection_index];
  hid_dbg(hdev, "collection->usage %x\n",
     collection->usage);

  callback = sensor_hub_get_callback(hdev,
    report->field[i]->physical ? report->field[i]->physical :
            report->field[i]->application,
    report->field[i]->usage[0].collection_index,
    &hsdev, &priv);
  if (!callback) {
   ptr += sz;
   continue;
  }
  if (hsdev->pending.status && (hsdev->pending.attr_usage_id ==
           report->field[i]->usage->hid ||
           hsdev->pending.attr_usage_id ==
           report->field[i]->logical)) {
   hid_dbg(hdev, "data was pending ...\n");
   hsdev->pending.raw_data = kmemdup(ptr, sz, GFP_ATOMIC);
   if (hsdev->pending.raw_data)
    hsdev->pending.raw_size = sz;
   else
    hsdev->pending.raw_size = 0;
   complete(&hsdev->pending.ready);
  }
  if (callback->capture_sample) {
   if (report->field[i]->logical)
    callback->capture_sample(hsdev,
     report->field[i]->logical, sz, ptr,
     callback->pdev);
   else
    callback->capture_sample(hsdev,
     report->field[i]->usage->hid, sz, ptr,
     callback->pdev);
  }
  ptr += sz;
 }
 if (callback && collection && callback->send_event)
  callback->send_event(hsdev, collection->usage,
    callback->pdev);
 spin_unlock_irqrestore(&pdata->lock, flags);

 return 1;
}

int sensor_hub_device_open(struct hid_sensor_hub_device *hsdev)
{
 int ret = 0;
 struct sensor_hub_data *data =  hid_get_drvdata(hsdev->hdev);

 mutex_lock(&data->mutex);
 if (!data->ref_cnt) {
  ret = hid_hw_open(hsdev->hdev);
  if (ret) {
   hid_err(hsdev->hdev, "failed to open hid device\n");
   mutex_unlock(&data->mutex);
   return ret;
  }
 }
 data->ref_cnt++;
 mutex_unlock(&data->mutex);

 return ret;
}
EXPORT_SYMBOL_GPL(sensor_hub_device_open);

void sensor_hub_device_close(struct hid_sensor_hub_device *hsdev)
{
 struct sensor_hub_data *data =  hid_get_drvdata(hsdev->hdev);

 mutex_lock(&data->mutex);
 data->ref_cnt--;
 if (!data->ref_cnt)
  hid_hw_close(hsdev->hdev);
 mutex_unlock(&data->mutex);
}
EXPORT_SYMBOL_GPL(sensor_hub_device_close);

static const __u8 *sensor_hub_report_fixup(struct hid_device *hdev, __u8 *rdesc,
  unsigned int *rsize)
{
 /*
 * Checks if the report descriptor of Thinkpad Helix 2 has a logical
 * minimum for magnetic flux axis greater than the maximum.
 */
 if (hdev->product == USB_DEVICE_ID_TEXAS_INSTRUMENTS_LENOVO_YOGA &&
  *rsize == 2558 && rdesc[913] == 0x17 && rdesc[914] == 0x40 &&
  rdesc[915] == 0x81 && rdesc[916] == 0x08 &&
  rdesc[917] == 0x00 && rdesc[918] == 0x27 &&
  rdesc[921] == 0x07 && rdesc[922] == 0x00) {
  /* Sets negative logical minimum for mag x, y and z */
  rdesc[914] = rdesc[935] = rdesc[956] = 0xc0;
  rdesc[915] = rdesc[936] = rdesc[957] = 0x7e;
  rdesc[916] = rdesc[937] = rdesc[958] = 0xf7;
  rdesc[917] = rdesc[938] = rdesc[959] = 0xff;
 }

 return rdesc;
}

static int sensor_hub_probe(struct hid_device *hdev,
    const struct hid_device_id *id)
{
 int ret;
 struct sensor_hub_data *sd;
 int i;
 char *name;
 int dev_cnt;
 struct hid_sensor_hub_device *hsdev;
 struct hid_sensor_hub_device *last_hsdev = NULL;
 struct hid_sensor_hub_device *collection_hsdev = NULL;

 sd = devm_kzalloc(&hdev->dev, sizeof(*sd), GFP_KERNEL);
 if (!sd) {
  hid_err(hdev, "cannot allocate Sensor data\n");
  return -ENOMEM;
 }

 hid_set_drvdata(hdev, sd);

 spin_lock_init(&sd->lock);
 spin_lock_init(&sd->dyn_callback_lock);
 mutex_init(&sd->mutex);
 ret = hid_parse(hdev);
 if (ret) {
  hid_err(hdev, "parse failed\n");
  return ret;
 }
 INIT_LIST_HEAD(&hdev->inputs);

 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT | HID_CONNECT_DRIVER);
 if (ret) {
  hid_err(hdev, "hw start failed\n");
  return ret;
 }
 INIT_LIST_HEAD(&sd->dyn_callback_list);
 sd->hid_sensor_client_cnt = 0;

 dev_cnt = sensor_hub_get_physical_device_count(hdev);
 if (dev_cnt > HID_MAX_PHY_DEVICES) {
  hid_err(hdev, "Invalid Physical device count\n");
  ret = -EINVAL;
  goto err_stop_hw;
 }
 sd->hid_sensor_hub_client_devs = devm_kcalloc(&hdev->dev,
            dev_cnt,
            sizeof(struct mfd_cell),
            GFP_KERNEL);
 if (sd->hid_sensor_hub_client_devs == NULL) {
  hid_err(hdev, "Failed to allocate memory for mfd cells\n");
  ret = -ENOMEM;
  goto err_stop_hw;
 }

 for (i = 0; i < hdev->maxcollection; ++i) {
  struct hid_collection *collection = &hdev->collection[i];

  if (collection->type == HID_COLLECTION_PHYSICAL ||
      collection->type == HID_COLLECTION_APPLICATION) {

   hsdev = devm_kzalloc(&hdev->dev, sizeof(*hsdev),
          GFP_KERNEL);
   if (!hsdev) {
    hid_err(hdev, "cannot allocate hid_sensor_hub_device\n");
    ret = -ENOMEM;
    goto err_stop_hw;
   }
   hsdev->hdev = hdev;
   hsdev->vendor_id = hdev->vendor;
   hsdev->product_id = hdev->product;
   hsdev->usage = collection->usage;
   hsdev->mutex_ptr = devm_kzalloc(&hdev->dev,
       sizeof(struct mutex),
       GFP_KERNEL);
   if (!hsdev->mutex_ptr) {
    ret = -ENOMEM;
    goto err_stop_hw;
   }
   mutex_init(hsdev->mutex_ptr);
   hsdev->start_collection_index = i;
   if (last_hsdev)
    last_hsdev->end_collection_index = i;
   last_hsdev = hsdev;
   name = devm_kasprintf(&hdev->dev, GFP_KERNEL,
           "HID-SENSOR-%x",
           collection->usage);
   if (name == NULL) {
    hid_err(hdev, "Failed MFD device name\n");
    ret = -ENOMEM;
    goto err_stop_hw;
   }
   sd->hid_sensor_hub_client_devs[
    sd->hid_sensor_client_cnt].name = name;
   sd->hid_sensor_hub_client_devs[
    sd->hid_sensor_client_cnt].platform_data =
       hsdev;
   sd->hid_sensor_hub_client_devs[
    sd->hid_sensor_client_cnt].pdata_size =
       sizeof(*hsdev);
   hid_dbg(hdev, "Adding %s:%d\n", name,
     hsdev->start_collection_index);
   sd->hid_sensor_client_cnt++;
   if (collection_hsdev)
    collection_hsdev->end_collection_index = i;
   if (collection->type == HID_COLLECTION_APPLICATION &&
       collection->usage == HID_USAGE_SENSOR_COLLECTION)
    collection_hsdev = hsdev;
  }
 }
 if (last_hsdev)
  last_hsdev->end_collection_index = i;
 if (collection_hsdev)
  collection_hsdev->end_collection_index = i;

 ret = mfd_add_hotplug_devices(&hdev->dev,
   sd->hid_sensor_hub_client_devs,
   sd->hid_sensor_client_cnt);
 if (ret < 0)
  goto err_stop_hw;

 return ret;

err_stop_hw:
 hid_hw_stop(hdev);

 return ret;
}

static int sensor_hub_finalize_pending_fn(struct device *dev, void *data)
{
 struct hid_sensor_hub_device *hsdev = dev->platform_data;

 if (hsdev->pending.status)
  complete(&hsdev->pending.ready);

 return 0;
}

static void sensor_hub_remove(struct hid_device *hdev)
{
 struct sensor_hub_data *data = hid_get_drvdata(hdev);
 unsigned long flags;

 hid_dbg(hdev, " hardware removed\n");
 hid_hw_close(hdev);
 hid_hw_stop(hdev);

 spin_lock_irqsave(&data->lock, flags);
 device_for_each_child(&hdev->dev, NULL,
         sensor_hub_finalize_pending_fn);
 spin_unlock_irqrestore(&data->lock, flags);

 mfd_remove_devices(&hdev->dev);
 mutex_destroy(&data->mutex);
}

static const struct hid_device_id sensor_hub_devices[] = {
 { HID_DEVICE(HID_BUS_ANY, HID_GROUP_SENSOR_HUB, HID_ANY_ID,
       HID_ANY_ID) },
 { }
};
MODULE_DEVICE_TABLE(hid, sensor_hub_devices);

static struct hid_driver sensor_hub_driver = {
 .name = "hid-sensor-hub",
 .id_table = sensor_hub_devices,
 .probe = sensor_hub_probe,
 .remove = sensor_hub_remove,
 .raw_event = sensor_hub_raw_event,
 .report_fixup = sensor_hub_report_fixup,
#ifdef CONFIG_PM
 .suspend = sensor_hub_suspend,
 .resume = sensor_hub_resume,
 .reset_resume = sensor_hub_reset_resume,
#endif
};
module_hid_driver(sensor_hub_driver);

MODULE_DESCRIPTION("HID Sensor Hub driver");
MODULE_AUTHOR("Srinivas Pandruvada ");
MODULE_LICENSE("GPL");