--- /dev/null
+/*
+ * 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");
projects / platform / kernel / linux-rpi.git / commitdiff