iio: hid: Add humidity sensor support
authorSong Hongyan <hongyan.song@intel.com>
Mon, 20 Mar 2017 14:28:45 +0000 (22:28 +0800)
committerJonathan Cameron <jic23@kernel.org>
Sat, 25 Mar 2017 16:32:24 +0000 (16:32 +0000)
Environmental humidity sensor is a hid defined sensor,
it shows raw humidity measurement of air.

More information can be found in:
http://www.usb.org/developers/hidpage/HUTRR39b.pdf

According to IIO ABI definition, humidityrelative data output unit is
milli percent. Add the unit convert from percent to milli percent.

Signed-off-by: Song Hongyan <hongyan.song@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
drivers/iio/common/hid-sensors/hid-sensor-attributes.c
drivers/iio/humidity/Kconfig
drivers/iio/humidity/Makefile
drivers/iio/humidity/hid-sensor-humidity.c [new file with mode: 0644]
include/linux/hid-sensor-ids.h

index cfb2fdc3177f1bfa9f112421f77e96bedadfc03b..81647cc64a7b7ea07be3c3533ea020e6fa5a12a6 100644 (file)
@@ -71,6 +71,8 @@ static struct {
 
        {HID_USAGE_SENSOR_TEMPERATURE, 0, 1000, 0},
        {HID_USAGE_SENSOR_TEMPERATURE, HID_USAGE_SENSOR_UNITS_DEGREES, 1000, 0},
+
+       {HID_USAGE_SENSOR_HUMIDITY, 0, 1000, 0},
 };
 
 static int pow_10(unsigned power)
index 912477d54be2e7894f493b0250f63a5be8fbb5b9..14b9ce453d9de004cd51459857e68667ff0cdd00 100644 (file)
@@ -36,6 +36,20 @@ config HDC100X
          To compile this driver as a module, choose M here: the module
          will be called hdc100x.
 
+config HID_SENSOR_HUMIDITY
+       tristate "HID Environmental humidity sensor"
+       depends on HID_SENSOR_HUB
+       select IIO_BUFFER
+       select IIO_TRIGGERED_BUFFER
+       select HID_SENSOR_IIO_COMMON
+       select HID_SENSOR_IIO_TRIGGER
+       help
+         Say yes here to build support for the HID SENSOR
+         humidity driver
+
+         To compile this driver as a module, choose M here: the module
+         will be called hid-sensor-humidity.
+
 config HTS221
        tristate "STMicroelectronics HTS221 sensor Driver"
        depends on (I2C || SPI)
index a6850e47c100981264081310855e5e061620728e..be0dedeb8f3c60c3eb232a99fca77142ffe1030d 100644 (file)
@@ -5,6 +5,7 @@
 obj-$(CONFIG_AM2315) += am2315.o
 obj-$(CONFIG_DHT11) += dht11.o
 obj-$(CONFIG_HDC100X) += hdc100x.o
+obj-$(CONFIG_HID_SENSOR_HUMIDITY) += hid-sensor-humidity.o
 
 hts221-y := hts221_core.o \
            hts221_buffer.o
@@ -15,3 +16,5 @@ obj-$(CONFIG_HTS221_SPI) += hts221_spi.o
 obj-$(CONFIG_HTU21) += htu21.o
 obj-$(CONFIG_SI7005) += si7005.o
 obj-$(CONFIG_SI7020) += si7020.o
+
+ccflags-y += -I$(srctree)/drivers/iio/common/hid-sensors
diff --git a/drivers/iio/humidity/hid-sensor-humidity.c b/drivers/iio/humidity/hid-sensor-humidity.c
new file mode 100644 (file)
index 0000000..6e09c1a
--- /dev/null
@@ -0,0 +1,315 @@
+/*
+ * 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");
index 46dd1f27d2f21f3e0d8e2099025628bcfbee5c2d..761f86242473609ed94cee70672e9e639e32e818 100644 (file)
 #define        HID_USAGE_SENSOR_TEMPERATURE                            0x200033
 #define        HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE         0x200434
 
+/* humidity */
+#define HID_USAGE_SENSOR_HUMIDITY                              0x200032
+#define HID_USAGE_SENSOR_ATMOSPHERIC_HUMIDITY                  0x200433
+
 /* Gyro 3D: (200076) */
 #define HID_USAGE_SENSOR_GYRO_3D                               0x200076
 #define HID_USAGE_SENSOR_DATA_ANGL_VELOCITY                    0x200456