/*
   * 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/platform_device.h>
  #include <linux/module.h>
  #include <linux/interrupt.h>
  #include <linux/irq.h>
  #include <linux/slab.h>
  #include <linux/delay.h>
  #include <linux/hid-sensor-hub.h>
  #include <linux/iio/iio.h>
  #include <linux/iio/trigger.h>
  #include <linux/iio/sysfs.h>
  #include "hid-sensor-trigger.h"
  
  static int _hid_sensor_power_state(struct hid_sensor_common *st, bool state)
  {
  	int state_val;
  	int report_val;
  	s32 poll_value = 0;
  
  	if (state) {
  		if (!atomic_read(&st->user_requested_state))
  			return 0;
  		if (sensor_hub_device_open(st->hsdev))
  			return -EIO;
  
  		atomic_inc(&st->data_ready);
  
  		state_val = hid_sensor_get_usage_index(st->hsdev,
  			st->power_state.report_id,
  			st->power_state.index,
  			HID_USAGE_SENSOR_PROP_POWER_STATE_D0_FULL_POWER_ENUM);
  		report_val = hid_sensor_get_usage_index(st->hsdev,
  			st->report_state.report_id,
  			st->report_state.index,
  			HID_USAGE_SENSOR_PROP_REPORTING_STATE_ALL_EVENTS_ENUM);
  
  		poll_value = hid_sensor_read_poll_value(st);
  	} else {
  		int val;
  
  		val = atomic_dec_if_positive(&st->data_ready);
  		if (val < 0)
  			return 0;
  
  		sensor_hub_device_close(st->hsdev);
  		state_val = hid_sensor_get_usage_index(st->hsdev,
  			st->power_state.report_id,
  			st->power_state.index,
  			HID_USAGE_SENSOR_PROP_POWER_STATE_D4_POWER_OFF_ENUM);
  		report_val = hid_sensor_get_usage_index(st->hsdev,
  			st->report_state.report_id,
  			st->report_state.index,
  			HID_USAGE_SENSOR_PROP_REPORTING_STATE_NO_EVENTS_ENUM);
  	}
  
  	if (state_val >= 0) {
  		state_val += st->power_state.logical_minimum;
  		sensor_hub_set_feature(st->hsdev, st->power_state.report_id,
  				       st->power_state.index, sizeof(state_val),
  				       &state_val);
  	}
  
  	if (report_val >= 0) {
  		report_val += st->report_state.logical_minimum;
  		sensor_hub_set_feature(st->hsdev, st->report_state.report_id,
  				       st->report_state.index,
  				       sizeof(report_val),
  				       &report_val);
  	}
  
  	sensor_hub_get_feature(st->hsdev, st->power_state.report_id,
  			       st->power_state.index,
  			       sizeof(state_val), &state_val);
  	if (state && poll_value)
  		msleep_interruptible(poll_value * 2);
  
  	return 0;
  }
  EXPORT_SYMBOL(hid_sensor_power_state);
  
  int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
  {
  
  #ifdef CONFIG_PM
  	int ret;
  
  	atomic_set(&st->user_requested_state, state);
  	if (state)
  		ret = pm_runtime_get_sync(&st->pdev->dev);
  	else {
  		pm_runtime_mark_last_busy(&st->pdev->dev);
  		ret = pm_runtime_put_autosuspend(&st->pdev->dev);
  	}
  	if (ret < 0) {
  		if (state)
  			pm_runtime_put_noidle(&st->pdev->dev);
  		return ret;
  	}
  
   	return 0;
  #else
  	atomic_set(&st->user_requested_state, state);
  	return _hid_sensor_power_state(st, state);
  #endif
  }
  
  static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
  						bool state)
  {
  	return hid_sensor_power_state(iio_trigger_get_drvdata(trig), state);
  }
  
  void hid_sensor_remove_trigger(struct hid_sensor_common *attrb)
  {
  	iio_trigger_unregister(attrb->trigger);
  	iio_trigger_free(attrb->trigger);
  }
  EXPORT_SYMBOL(hid_sensor_remove_trigger);
  
  static const struct iio_trigger_ops hid_sensor_trigger_ops = {
  	.owner = THIS_MODULE,
  	.set_trigger_state = &hid_sensor_data_rdy_trigger_set_state,
  };
  
  int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name,
  				struct hid_sensor_common *attrb)
  {
  	int ret;
  	struct iio_trigger *trig;
  
  	trig = iio_trigger_alloc("%s-dev%d", name, indio_dev->id);
  	if (trig == NULL) {
  		dev_err(&indio_dev->dev, "Trigger Allocate Failed
  ");
  		ret = -ENOMEM;
  		goto error_ret;
  	}
  
  	trig->dev.parent = indio_dev->dev.parent;
  	iio_trigger_set_drvdata(trig, attrb);
  	trig->ops = &hid_sensor_trigger_ops;
  	ret = iio_trigger_register(trig);
  
  	if (ret) {
  		dev_err(&indio_dev->dev, "Trigger Register Failed
  ");
  		goto error_free_trig;
  	}
  	attrb->trigger = trig;
  	indio_dev->trig = iio_trigger_get(trig);
  
  	ret = pm_runtime_set_active(&indio_dev->dev);
  	if (ret)
  		goto error_unreg_trigger;
  
  	iio_device_set_drvdata(indio_dev, attrb);
  	pm_suspend_ignore_children(&attrb->pdev->dev, true);
  	pm_runtime_enable(&attrb->pdev->dev);
  	/* Default to 3 seconds, but can be changed from sysfs */
  	pm_runtime_set_autosuspend_delay(&attrb->pdev->dev,
  					 3000);
  	pm_runtime_use_autosuspend(&attrb->pdev->dev);
  
  	return ret;
  error_unreg_trigger:
  	iio_trigger_unregister(trig);
  error_free_trig:
  	iio_trigger_free(trig);
  error_ret:
  	return ret;
  }
  EXPORT_SYMBOL(hid_sensor_setup_trigger);
  
  #ifdef CONFIG_PM
  static int hid_sensor_suspend(struct device *dev)
  {
  	struct platform_device *pdev = to_platform_device(dev);
  	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
  	struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
  
  	return _hid_sensor_power_state(attrb, false);
  }
  
  static int hid_sensor_resume(struct device *dev)
  {
  	struct platform_device *pdev = to_platform_device(dev);
  	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
  	struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
  
  	return _hid_sensor_power_state(attrb, true);
  }
  
  #endif
  
  const struct dev_pm_ops hid_sensor_pm_ops = {
  	SET_SYSTEM_SLEEP_PM_OPS(hid_sensor_suspend, hid_sensor_resume)
  	SET_RUNTIME_PM_OPS(hid_sensor_suspend,
  			   hid_sensor_resume, NULL)
  };
  EXPORT_SYMBOL(hid_sensor_pm_ops);
  
  MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
  MODULE_DESCRIPTION("HID Sensor trigger processing");
  MODULE_LICENSE("GPL");