1 files changed, 792 insertions, 0 deletions

diff --git a/drivers/hid/hid-sensor-hub.c b/drivers/hid/hid-sensor-hub.c
new file mode 100644
index 000000000..ef62f36eb
--- /dev/null
+++ b/drivers/hid/hid-sensor-hub.c
@@ -0,0 +1,792 @@
+/*
+ * HID Sensors Driver
+ * Copyright (c) 2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#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
+ * @hsdev:		Stored hid instance for current 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;
+	unsigned long quirks;
+	int ref_cnt;
+};
+
+/**
+ * struct hid_sensor_hub_callbacks_list - Stores callback list
+ * @list:		list head.
+ * @usage_id:		usage id for a physical 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->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]->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 __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);
+	sd->quirks = id->driver_data;
+
+	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, 0);
+	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 void sensor_hub_remove(struct hid_device *hdev)
+{
+	struct sensor_hub_data *data = hid_get_drvdata(hdev);
+	unsigned long flags;
+	int i;
+
+	hid_dbg(hdev, " hardware removed\n");
+	hid_hw_close(hdev);
+	hid_hw_stop(hdev);
+	spin_lock_irqsave(&data->lock, flags);
+	for (i = 0; i < data->hid_sensor_client_cnt; ++i) {
+		struct hid_sensor_hub_device *hsdev =
+			data->hid_sensor_hub_client_devs[i].platform_data;
+		if (hsdev->pending.status)
+			complete(&hsdev->pending.ready);
+	}
+	spin_unlock_irqrestore(&data->lock, flags);
+	mfd_remove_devices(&hdev->dev);
+	hid_set_drvdata(hdev, NULL);
+	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 <srinivas.pandruvada@intel.com>");
+MODULE_LICENSE("GPL");