drivers/iio/humidity/hid-sensor-humidity.c - arm/linux - Git at Google

 /*
  * HID Sensors Driver
  * Copyright (c) 2017, 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.
  */
 #include <linux/device.h>
 #include <linux/hid-sensor-hub.h>
 #include <linux/iio/buffer.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/triggered_buffer.h>
 #include <linux/iio/trigger_consumer.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>

 #include "hid-sensor-trigger.h"

 struct hid_humidity_state {
 	struct hid_sensor_common common_attributes;
 	struct hid_sensor_hub_attribute_info humidity_attr;
 	s32 humidity_data;
 	int scale_pre_decml;
 	int scale_post_decml;
 	int scale_precision;
 	int value_offset;
 };

 /* Channel definitions */
 static const struct iio_chan_spec humidity_channels[] = {
 	{
 		.type = IIO_HUMIDITYRELATIVE,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 			BIT(IIO_CHAN_INFO_SCALE) |
 			BIT(IIO_CHAN_INFO_SAMP_FREQ) |
 			BIT(IIO_CHAN_INFO_HYSTERESIS),
 	},
 	IIO_CHAN_SOFT_TIMESTAMP(1)
 };

 /* Adjust channel real bits based on report descriptor */
 static void humidity_adjust_channel_bit_mask(struct iio_chan_spec *channels,
 					int channel, int size)
 {
 	channels[channel].scan_type.sign = 's';
 	/* Real storage bits will change based on the report desc. */
 	channels[channel].scan_type.realbits = size * 8;
 	/* Maximum size of a sample to capture is s32 */
 	channels[channel].scan_type.storagebits = sizeof(s32) * 8;
 }

 static int humidity_read_raw(struct iio_dev *indio_dev,
 				struct iio_chan_spec const *chan,
 				int *val, int *val2, long mask)
 {
 	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		if (chan->type != IIO_HUMIDITYRELATIVE)
 			return -EINVAL;
 		hid_sensor_power_state(&humid_st->common_attributes, true);
 		*val = sensor_hub_input_attr_get_raw_value(
 				humid_st->common_attributes.hsdev,
 				HID_USAGE_SENSOR_HUMIDITY,
 				HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
 				humid_st->humidity_attr.report_id,
 				SENSOR_HUB_SYNC);
 		hid_sensor_power_state(&humid_st->common_attributes, false);

 		return IIO_VAL_INT;

 	case IIO_CHAN_INFO_SCALE:
 		*val = humid_st->scale_pre_decml;
 		*val2 = humid_st->scale_post_decml;

 		return humid_st->scale_precision;

 	case IIO_CHAN_INFO_OFFSET:
 		*val = humid_st->value_offset;

 		return IIO_VAL_INT;

 	case IIO_CHAN_INFO_SAMP_FREQ:
 		return hid_sensor_read_samp_freq_value(
 				&humid_st->common_attributes, val, val2);

 	case IIO_CHAN_INFO_HYSTERESIS:
 		return hid_sensor_read_raw_hyst_value(
 				&humid_st->common_attributes, val, val2);

 	default:
 		return -EINVAL;
 	}
 }

 static int humidity_write_raw(struct iio_dev *indio_dev,
 				struct iio_chan_spec const *chan,
 				int val, int val2, long mask)
 {
 	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

 	switch (mask) {
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		return hid_sensor_write_samp_freq_value(
 				&humid_st->common_attributes, val, val2);

 	case IIO_CHAN_INFO_HYSTERESIS:
 		return hid_sensor_write_raw_hyst_value(
 				&humid_st->common_attributes, val, val2);

 	default:
 		return -EINVAL;
 	}
 }

 static const struct iio_info humidity_info = {
 	.driver_module = THIS_MODULE,
 	.read_raw = &humidity_read_raw,
 	.write_raw = &humidity_write_raw,
 };

 /* Callback handler to send event after all samples are received and captured */
 static int humidity_proc_event(struct hid_sensor_hub_device *hsdev,
 				unsigned int usage_id, void *pdev)
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

 	if (atomic_read(&humid_st->common_attributes.data_ready))
 		iio_push_to_buffers_with_timestamp(indio_dev,
 					&humid_st->humidity_data,
 					iio_get_time_ns(indio_dev));

 	return 0;
 }

 /* Capture samples in local storage */
 static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev,
 				unsigned int usage_id, size_t raw_len,
 				char *raw_data, void *pdev)
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

 	switch (usage_id) {
 	case HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY:
 		humid_st->humidity_data = *(s32 *)raw_data;

 		return 0;
 	default:
 		return -EINVAL;
 	}
 }

 /* Parse report which is specific to an usage id */
 static int humidity_parse_report(struct platform_device *pdev,
 				struct hid_sensor_hub_device *hsdev,
 				struct iio_chan_spec *channels,
 				unsigned int usage_id,
 				struct hid_humidity_state *st)
 {
 	int ret;

 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 					usage_id,
 					HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
 					&st->humidity_attr);
 	if (ret < 0)
 		return ret;

 	humidity_adjust_channel_bit_mask(channels, 0, st->humidity_attr.size);

 	st->scale_precision = hid_sensor_format_scale(
 						HID_USAGE_SENSOR_HUMIDITY,
 						&st->humidity_attr,
 						&st->scale_pre_decml,
 						&st->scale_post_decml);

 	/* Set Sensitivity field ids, when there is no individual modifier */
 	if (st->common_attributes.sensitivity.index < 0)
 		sensor_hub_input_get_attribute_info(hsdev,
 			HID_FEATURE_REPORT, usage_id,
 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 			HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
 			&st->common_attributes.sensitivity);

 	return ret;
 }

 static struct hid_sensor_hub_callbacks humidity_callbacks = {
 	.send_event = &humidity_proc_event,
 	.capture_sample = &humidity_capture_sample,
 };

 /* Function to initialize the processing for usage id */
 static int hid_humidity_probe(struct platform_device *pdev)
 {
 	static const char *name = "humidity";
 	struct iio_dev *indio_dev;
 	struct hid_humidity_state *humid_st;
 	struct iio_chan_spec *humid_chans;
 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 	int ret;

 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*humid_st));
 	if (!indio_dev)
 		return -ENOMEM;

 	humid_st = iio_priv(indio_dev);
 	humid_st->common_attributes.hsdev = hsdev;
 	humid_st->common_attributes.pdev = pdev;

 	ret = hid_sensor_parse_common_attributes(hsdev,
 					HID_USAGE_SENSOR_HUMIDITY,
 					&humid_st->common_attributes);
 	if (ret)
 		return ret;

 	humid_chans = devm_kmemdup(&indio_dev->dev, humidity_channels,
 					sizeof(humidity_channels), GFP_KERNEL);
 	if (!humid_chans)
 		return -ENOMEM;

 	ret = humidity_parse_report(pdev, hsdev, humid_chans,
 				HID_USAGE_SENSOR_HUMIDITY, humid_st);
 	if (ret)
 		return ret;

 	indio_dev->channels = humid_chans;
 	indio_dev->num_channels = ARRAY_SIZE(humidity_channels);
 	indio_dev->dev.parent = &pdev->dev;
 	indio_dev->info = &humidity_info;
 	indio_dev->name = name;
 	indio_dev->modes = INDIO_DIRECT_MODE;

 	ret = devm_iio_triggered_buffer_setup(&pdev->dev, indio_dev,
 					&iio_pollfunc_store_time, NULL, NULL);
 	if (ret)
 		return ret;

 	atomic_set(&humid_st->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 				&humid_st->common_attributes);
 	if (ret)
 		return ret;

 	platform_set_drvdata(pdev, indio_dev);

 	humidity_callbacks.pdev = pdev;
 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY,
 					&humidity_callbacks);
 	if (ret)
 		goto error_remove_trigger;

 	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto error_remove_callback;

 	return ret;

 error_remove_callback:
 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
 error_remove_trigger:
 	hid_sensor_remove_trigger(&humid_st->common_attributes);
 	return ret;
 }

 /* Function to deinitialize the processing for usage id */
 static int hid_humidity_remove(struct platform_device *pdev)
 {
 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

 	iio_device_unregister(indio_dev);
 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
 	hid_sensor_remove_trigger(&humid_st->common_attributes);

 	return 0;
 }

 static const struct platform_device_id hid_humidity_ids[] = {
 	{
 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 		.name = "HID-SENSOR-200032",
 	},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(platform, hid_humidity_ids);

 static struct platform_driver hid_humidity_platform_driver = {
 	.id_table = hid_humidity_ids,
 	.driver = {
 		.name	= KBUILD_MODNAME,
 		.pm	= &hid_sensor_pm_ops,
 	},
 	.probe		= hid_humidity_probe,
 	.remove		= hid_humidity_remove,
 };
 module_platform_driver(hid_humidity_platform_driver);

 MODULE_DESCRIPTION("HID Environmental humidity sensor");
 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
 MODULE_LICENSE("GPL v2");
	/*
	* HID Sensors Driver
	* Copyright (c) 2017, 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.
	*/
	#include <linux/device.h>
	#include <linux/hid-sensor-hub.h>
	#include <linux/iio/buffer.h>
	#include <linux/iio/iio.h>
	#include <linux/iio/triggered_buffer.h>
	#include <linux/iio/trigger_consumer.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>

	#include "hid-sensor-trigger.h"

	struct hid_humidity_state {
	struct hid_sensor_common common_attributes;
	struct hid_sensor_hub_attribute_info humidity_attr;
	s32 humidity_data;
	int scale_pre_decml;
	int scale_post_decml;
	int scale_precision;
	int value_offset;
	};

	/* Channel definitions */
	static const struct iio_chan_spec humidity_channels[] = {
	{
	.type = IIO_HUMIDITYRELATIVE,
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) \|
	BIT(IIO_CHAN_INFO_SCALE) \|
	BIT(IIO_CHAN_INFO_SAMP_FREQ) \|
	BIT(IIO_CHAN_INFO_HYSTERESIS),
	},
	IIO_CHAN_SOFT_TIMESTAMP(1)
	};

	/* Adjust channel real bits based on report descriptor */
	static void humidity_adjust_channel_bit_mask(struct iio_chan_spec *channels,
	int channel, int size)
	{
	channels[channel].scan_type.sign = 's';
	/* Real storage bits will change based on the report desc. */
	channels[channel].scan_type.realbits = size * 8;
	/* Maximum size of a sample to capture is s32 */
	channels[channel].scan_type.storagebits = sizeof(s32) * 8;
	}

	static int humidity_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	if (chan->type != IIO_HUMIDITYRELATIVE)
	return -EINVAL;
	hid_sensor_power_state(&humid_st->common_attributes, true);
	*val = sensor_hub_input_attr_get_raw_value(
	humid_st->common_attributes.hsdev,
	HID_USAGE_SENSOR_HUMIDITY,
	HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
	humid_st->humidity_attr.report_id,
	SENSOR_HUB_SYNC);
	hid_sensor_power_state(&humid_st->common_attributes, false);

	return IIO_VAL_INT;

	case IIO_CHAN_INFO_SCALE:
	*val = humid_st->scale_pre_decml;
	*val2 = humid_st->scale_post_decml;

	return humid_st->scale_precision;

	case IIO_CHAN_INFO_OFFSET:
	*val = humid_st->value_offset;

	return IIO_VAL_INT;

	case IIO_CHAN_INFO_SAMP_FREQ:
	return hid_sensor_read_samp_freq_value(
	&humid_st->common_attributes, val, val2);

	case IIO_CHAN_INFO_HYSTERESIS:
	return hid_sensor_read_raw_hyst_value(
	&humid_st->common_attributes, val, val2);

	default:
	return -EINVAL;
	}
	}

	static int humidity_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_SAMP_FREQ:
	return hid_sensor_write_samp_freq_value(
	&humid_st->common_attributes, val, val2);

	case IIO_CHAN_INFO_HYSTERESIS:
	return hid_sensor_write_raw_hyst_value(
	&humid_st->common_attributes, val, val2);

	default:
	return -EINVAL;
	}
	}

	static const struct iio_info humidity_info = {
	.driver_module = THIS_MODULE,
	.read_raw = &humidity_read_raw,
	.write_raw = &humidity_write_raw,
	};

	/* Callback handler to send event after all samples are received and captured */
	static int humidity_proc_event(struct hid_sensor_hub_device *hsdev,
	unsigned int usage_id, void *pdev)
	{
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

	if (atomic_read(&humid_st->common_attributes.data_ready))
	iio_push_to_buffers_with_timestamp(indio_dev,
	&humid_st->humidity_data,
	iio_get_time_ns(indio_dev));

	return 0;
	}

	/* Capture samples in local storage */
	static int humidity_capture_sample(struct hid_sensor_hub_device *hsdev,
	unsigned int usage_id, size_t raw_len,
	char raw_data, void pdev)
	{
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

	switch (usage_id) {
	case HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY:
	humid_st->humidity_data = (s32 )raw_data;

	return 0;
	default:
	return -EINVAL;
	}
	}

	/* Parse report which is specific to an usage id */
	static int humidity_parse_report(struct platform_device *pdev,
	struct hid_sensor_hub_device *hsdev,
	struct iio_chan_spec *channels,
	unsigned int usage_id,
	struct hid_humidity_state *st)
	{
	int ret;

	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
	usage_id,
	HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
	&st->humidity_attr);
	if (ret < 0)
	return ret;

	humidity_adjust_channel_bit_mask(channels, 0, st->humidity_attr.size);

	st->scale_precision = hid_sensor_format_scale(
	HID_USAGE_SENSOR_HUMIDITY,
	&st->humidity_attr,
	&st->scale_pre_decml,
	&st->scale_post_decml);

	/* Set Sensitivity field ids, when there is no individual modifier */
	if (st->common_attributes.sensitivity.index < 0)
	sensor_hub_input_get_attribute_info(hsdev,
	HID_FEATURE_REPORT, usage_id,
	HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS \|
	HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY,
	&st->common_attributes.sensitivity);

	return ret;
	}

	static struct hid_sensor_hub_callbacks humidity_callbacks = {
	.send_event = &humidity_proc_event,
	.capture_sample = &humidity_capture_sample,
	};

	/* Function to initialize the processing for usage id */
	static int hid_humidity_probe(struct platform_device *pdev)
	{
	static const char *name = "humidity";
	struct iio_dev *indio_dev;
	struct hid_humidity_state *humid_st;
	struct iio_chan_spec *humid_chans;
	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
	int ret;

	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*humid_st));
	if (!indio_dev)
	return -ENOMEM;

	humid_st = iio_priv(indio_dev);
	humid_st->common_attributes.hsdev = hsdev;
	humid_st->common_attributes.pdev = pdev;

	ret = hid_sensor_parse_common_attributes(hsdev,
	HID_USAGE_SENSOR_HUMIDITY,
	&humid_st->common_attributes);
	if (ret)
	return ret;

	humid_chans = devm_kmemdup(&indio_dev->dev, humidity_channels,
	sizeof(humidity_channels), GFP_KERNEL);
	if (!humid_chans)
	return -ENOMEM;

	ret = humidity_parse_report(pdev, hsdev, humid_chans,
	HID_USAGE_SENSOR_HUMIDITY, humid_st);
	if (ret)
	return ret;

	indio_dev->channels = humid_chans;
	indio_dev->num_channels = ARRAY_SIZE(humidity_channels);
	indio_dev->dev.parent = &pdev->dev;
	indio_dev->info = &humidity_info;
	indio_dev->name = name;
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = devm_iio_triggered_buffer_setup(&pdev->dev, indio_dev,
	&iio_pollfunc_store_time, NULL, NULL);
	if (ret)
	return ret;

	atomic_set(&humid_st->common_attributes.data_ready, 0);
	ret = hid_sensor_setup_trigger(indio_dev, name,
	&humid_st->common_attributes);
	if (ret)
	return ret;

	platform_set_drvdata(pdev, indio_dev);

	humidity_callbacks.pdev = pdev;
	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY,
	&humidity_callbacks);
	if (ret)
	goto error_remove_trigger;

	ret = iio_device_register(indio_dev);
	if (ret)
	goto error_remove_callback;

	return ret;

	error_remove_callback:
	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
	error_remove_trigger:
	hid_sensor_remove_trigger(&humid_st->common_attributes);
	return ret;
	}

	/* Function to deinitialize the processing for usage id */
	static int hid_humidity_remove(struct platform_device *pdev)
	{
	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	struct hid_humidity_state *humid_st = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_HUMIDITY);
	hid_sensor_remove_trigger(&humid_st->common_attributes);

	return 0;
	}

	static const struct platform_device_id hid_humidity_ids[] = {
	{
	/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
	.name = "HID-SENSOR-200032",
	},
	{ /* sentinel */ }
	};
	MODULE_DEVICE_TABLE(platform, hid_humidity_ids);

	static struct platform_driver hid_humidity_platform_driver = {
	.id_table = hid_humidity_ids,
	.driver = {
	.name = KBUILD_MODNAME,
	.pm = &hid_sensor_pm_ops,
	},
	.probe = hid_humidity_probe,
	.remove = hid_humidity_remove,
	};
	module_platform_driver(hid_humidity_platform_driver);

	MODULE_DESCRIPTION("HID Environmental humidity sensor");
	MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
	MODULE_LICENSE("GPL v2");