/*
   * 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.
   *
   */
  #ifndef _HID_SENSORS_HUB_H
  #define _HID_SENSORS_HUB_H
  
  #include <linux/hid.h>
  #include <linux/hid-sensor-ids.h>
  #include <linux/iio/iio.h>
  #include <linux/iio/trigger.h>
  
  /**
   * struct hid_sensor_hub_attribute_info - Attribute info
   * @usage_id:		Parent usage id of a physical device.
   * @attrib_id:		Attribute id for this attribute.
   * @report_id:		Report id in which this information resides.
   * @index:		Field index in the report.
   * @units:		Measurment unit for this attribute.
   * @unit_expo:		Exponent used in the data.
   * @size:		Size in bytes for data size.
   * @logical_minimum:	Logical minimum value for this attribute.
   * @logical_maximum:	Logical maximum value for this attribute.
   */
  struct hid_sensor_hub_attribute_info {
  	u32 usage_id;
  	u32 attrib_id;
  	s32 report_id;
  	s32 index;
  	s32 units;
  	s32 unit_expo;
  	s32 size;
  	s32 logical_minimum;
  	s32 logical_maximum;
  };
  
  /**
   * struct sensor_hub_pending - Synchronous read pending information
   * @status:		Pending status true/false.
   * @ready:		Completion synchronization data.
   * @usage_id:		Usage id for physical device, E.g. Gyro usage id.
   * @attr_usage_id:	Usage Id of a field, E.g. X-AXIS for a gyro.
   * @raw_size:		Response size for a read request.
   * @raw_data:		Place holder for received response.
   */
  struct sensor_hub_pending {
  	bool status;
  	struct completion ready;
  	u32 usage_id;
  	u32 attr_usage_id;
  	int raw_size;
  	u8  *raw_data;
  };
  
  /**
   * struct hid_sensor_hub_device - Stores the hub instance data
   * @hdev:		Stores the hid instance.
   * @vendor_id:		Vendor id of hub device.
   * @product_id:		Product id of hub device.
   * @usage:		Usage id for this hub device instance.
   * @start_collection_index: Starting index for a phy type collection
   * @end_collection_index: Last index for a phy type collection
   * @mutex_ptr:		synchronizing mutex pointer.
   * @pending:		Holds information of pending sync read request.
   */
  struct hid_sensor_hub_device {
  	struct hid_device *hdev;
  	u32 vendor_id;
  	u32 product_id;
  	u32 usage;
  	int start_collection_index;
  	int end_collection_index;
  	struct mutex *mutex_ptr;
  	struct sensor_hub_pending pending;
  };
  
  /**
   * struct hid_sensor_hub_callbacks - Client callback functions
   * @pdev:		Platform device instance of the client driver.
   * @suspend:		Suspend callback.
   * @resume:		Resume callback.
   * @capture_sample:	Callback to get a sample.
   * @send_event:		Send notification to indicate all samples are
   *			captured, process and send event
   */
  struct hid_sensor_hub_callbacks {
  	struct platform_device *pdev;
  	int (*suspend)(struct hid_sensor_hub_device *hsdev, void *priv);
  	int (*resume)(struct hid_sensor_hub_device *hsdev, void *priv);
  	int (*capture_sample)(struct hid_sensor_hub_device *hsdev,
  			u32 usage_id, size_t raw_len, char *raw_data,
  			void *priv);
  	int (*send_event)(struct hid_sensor_hub_device *hsdev, u32 usage_id,
  			 void *priv);
  };
  
  /**
  * sensor_hub_device_open() - Open hub device
  * @hsdev:	Hub device instance.
  *
  * Used to open hid device for sensor hub.
  */
  int sensor_hub_device_open(struct hid_sensor_hub_device *hsdev);
  
  /**
  * sensor_hub_device_clode() - Close hub device
  * @hsdev:	Hub device instance.
  *
  * Used to clode hid device for sensor hub.
  */
  void sensor_hub_device_close(struct hid_sensor_hub_device *hsdev);
  
  /* Registration functions */
  
  /**
  * sensor_hub_register_callback() - Register client callbacks
  * @hsdev:	Hub device instance.
  * @usage_id:	Usage id of the client (E.g. 0x200076 for Gyro).
  * @usage_callback: Callback function storage
  *
  * Used to register callbacks by client processing drivers. Sensor
  * hub core driver will call these callbacks to offload processing
  * of data streams and notifications.
  */
  int sensor_hub_register_callback(struct hid_sensor_hub_device *hsdev,
  			u32 usage_id,
  			struct hid_sensor_hub_callbacks *usage_callback);
  
  /**
  * sensor_hub_remove_callback() - Remove client callbacks
  * @hsdev:	Hub device instance.
  * @usage_id:	Usage id of the client (E.g. 0x200076 for Gyro).
  *
  * If there is a callback registred, this call will remove that
  * callbacks, so that it will stop data and event notifications.
  */
  int sensor_hub_remove_callback(struct hid_sensor_hub_device *hsdev,
  			u32 usage_id);
  
  
  /* Hid sensor hub core interfaces */
  
  /**
  * sensor_hub_input_get_attribute_info() - Get an attribute information
  * @hsdev:	Hub device instance.
  * @type:	Type of this attribute, input/output/feature
  * @usage_id:	Attribute usage id of parent physical device as per spec
  * @attr_usage_id:	Attribute usage id as per spec
  * @info:	return information about attribute after parsing report
  *
  * Parses report and returns the attribute information such as report id,
  * field index, units and exponet etc.
  */
  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);
  
  /**
  * sensor_hub_input_attr_get_raw_value() - Synchronous read request
  * @hsdev:	Hub device instance.
  * @usage_id:	Attribute usage id of parent physical device as per spec
  * @attr_usage_id:	Attribute usage id as per spec
  * @report_id:	Report id to look for
  * @flag:      Synchronous or asynchronous read
  *
  * Issues a synchronous or asynchronous read request for an input attribute.
  * Returns data upto 32 bits.
  */
  
  enum sensor_hub_read_flags {
  	SENSOR_HUB_SYNC,
  	SENSOR_HUB_ASYNC,
  };
  
  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
  );
  
  /**
  * sensor_hub_set_feature() - Feature set request
  * @hsdev:	Hub device instance.
  * @report_id:	Report id to look for
  * @field_index:	Field index inside a report
  * @buffer_size: size of the buffer
  * @buffer:	buffer to use in the feature set
  *
  * Used to set a field in feature report. For example this can set polling
  * interval, sensitivity, activate/deactivate state.
  */
  int sensor_hub_set_feature(struct hid_sensor_hub_device *hsdev, u32 report_id,
  			   u32 field_index, int buffer_size, void *buffer);
  
  /**
  * sensor_hub_get_feature() - Feature get request
  * @hsdev:	Hub device instance.
  * @report_id:	Report id to look for
  * @field_index:	Field index inside a report
  * @buffer_size:	size of the buffer
  * @buffer:	buffer to copy output
  *
  * Used to get a field in feature report. For example this can get polling
  * interval, sensitivity, activate/deactivate state. On success it returns
  * number of bytes copied to buffer. On failure, it returns value < 0.
  */
  int sensor_hub_get_feature(struct hid_sensor_hub_device *hsdev, u32 report_id,
  			   u32 field_index, int buffer_size, void *buffer);
  
  /* hid-sensor-attributes */
  
  /* Common hid sensor iio structure */
  struct hid_sensor_common {
  	struct hid_sensor_hub_device *hsdev;
  	struct platform_device *pdev;
  	unsigned usage_id;
  	atomic_t data_ready;
  	atomic_t user_requested_state;
  	struct iio_trigger *trigger;
  	struct hid_sensor_hub_attribute_info poll;
  	struct hid_sensor_hub_attribute_info report_state;
  	struct hid_sensor_hub_attribute_info power_state;
  	struct hid_sensor_hub_attribute_info sensitivity;
  };
  
  /* Convert from hid unit expo to regular exponent */
  static inline int hid_sensor_convert_exponent(int unit_expo)
  {
  	if (unit_expo < 0x08)
  		return unit_expo;
  	else if (unit_expo <= 0x0f)
  		return -(0x0f-unit_expo+1);
  	else
  		return 0;
  }
  
  int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
  					u32 usage_id,
  					struct hid_sensor_common *st);
  int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
  					int val1, int val2);
  int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
  					int *val1, int *val2);
  int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
  					int val1, int val2);
  int hid_sensor_read_samp_freq_value(struct hid_sensor_common *st,
  					int *val1, int *val2);
  
  int hid_sensor_get_usage_index(struct hid_sensor_hub_device *hsdev,
  				u32 report_id, int field_index, u32 usage_id);
  
  int hid_sensor_format_scale(u32 usage_id,
  			    struct hid_sensor_hub_attribute_info *attr_info,
  			    int *val0, int *val1);
  
  s32 hid_sensor_read_poll_value(struct hid_sensor_common *st);
  
  #endif