LXR linux/drivers/iio/temperature/hid-sensor-temperature.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * HID Sensors Driver
   4 * Copyright (c) 2017, Intel Corporation.
   5 */
   6#include <linux/device.h>
   7#include <linux/hid-sensor-hub.h>
   8#include <linux/iio/buffer.h>
   9#include <linux/iio/iio.h>
  10#include <linux/module.h>
  11#include <linux/mod_devicetable.h>
  12#include <linux/platform_device.h>
  13
  14#include "../common/hid-sensors/hid-sensor-trigger.h"
  15
  16struct temperature_state {
  17        struct hid_sensor_common common_attributes;
  18        struct hid_sensor_hub_attribute_info temperature_attr;
  19        struct {
  20                s32 temperature_data;
  21                u64 timestamp __aligned(8);
  22        } scan;
  23        int scale_pre_decml;
  24        int scale_post_decml;
  25        int scale_precision;
  26        int value_offset;
  27};
  28
  29static const u32 temperature_sensitivity_addresses[] = {
  30        HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  31};
  32
  33/* Channel definitions */
  34static const struct iio_chan_spec temperature_channels[] = {
  35        {
  36                .type = IIO_TEMP,
  37                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  38                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  39                        BIT(IIO_CHAN_INFO_SCALE) |
  40                        BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  41                        BIT(IIO_CHAN_INFO_HYSTERESIS),
  42        },
  43        IIO_CHAN_SOFT_TIMESTAMP(1),
  44};
  45
  46/* Adjust channel real bits based on report descriptor */
  47static void temperature_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  48                                        int channel, int size)
  49{
  50        channels[channel].scan_type.sign = 's';
  51        /* Real storage bits will change based on the report desc. */
  52        channels[channel].scan_type.realbits = size * 8;
  53        /* Maximum size of a sample to capture is s32 */
  54        channels[channel].scan_type.storagebits = sizeof(s32) * 8;
  55}
  56
  57static int temperature_read_raw(struct iio_dev *indio_dev,
  58                                struct iio_chan_spec const *chan,
  59                                int *val, int *val2, long mask)
  60{
  61        struct temperature_state *temp_st = iio_priv(indio_dev);
  62
  63        switch (mask) {
  64        case IIO_CHAN_INFO_RAW:
  65                if (chan->type != IIO_TEMP)
  66                        return -EINVAL;
  67                hid_sensor_power_state(
  68                        &temp_st->common_attributes, true);
  69                *val = sensor_hub_input_attr_get_raw_value(
  70                        temp_st->common_attributes.hsdev,
  71                        HID_USAGE_SENSOR_TEMPERATURE,
  72                        HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  73                        temp_st->temperature_attr.report_id,
  74                        SENSOR_HUB_SYNC,
  75                        temp_st->temperature_attr.logical_minimum < 0);
  76                hid_sensor_power_state(
  77                                &temp_st->common_attributes,
  78                                false);
  79
  80                return IIO_VAL_INT;
  81
  82        case IIO_CHAN_INFO_SCALE:
  83                *val = temp_st->scale_pre_decml;
  84                *val2 = temp_st->scale_post_decml;
  85                return temp_st->scale_precision;
  86
  87        case IIO_CHAN_INFO_OFFSET:
  88                *val = temp_st->value_offset;
  89                return IIO_VAL_INT;
  90
  91        case IIO_CHAN_INFO_SAMP_FREQ:
  92                return hid_sensor_read_samp_freq_value(
  93                                &temp_st->common_attributes, val, val2);
  94
  95        case IIO_CHAN_INFO_HYSTERESIS:
  96                return hid_sensor_read_raw_hyst_value(
  97                                &temp_st->common_attributes, val, val2);
  98        default:
  99                return -EINVAL;
 100        }
 101}
 102
 103static int temperature_write_raw(struct iio_dev *indio_dev,
 104                                struct iio_chan_spec const *chan,
 105                                int val, int val2, long mask)
 106{
 107        struct temperature_state *temp_st = iio_priv(indio_dev);
 108
 109        switch (mask) {
 110        case IIO_CHAN_INFO_SAMP_FREQ:
 111                return hid_sensor_write_samp_freq_value(
 112                                &temp_st->common_attributes, val, val2);
 113        case IIO_CHAN_INFO_HYSTERESIS:
 114                return hid_sensor_write_raw_hyst_value(
 115                                &temp_st->common_attributes, val, val2);
 116        default:
 117                return -EINVAL;
 118        }
 119}
 120
 121static const struct iio_info temperature_info = {
 122        .read_raw = &temperature_read_raw,
 123        .write_raw = &temperature_write_raw,
 124};
 125
 126/* Callback handler to send event after all samples are received and captured */
 127static int temperature_proc_event(struct hid_sensor_hub_device *hsdev,
 128                                unsigned int usage_id, void *pdev)
 129{
 130        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 131        struct temperature_state *temp_st = iio_priv(indio_dev);
 132
 133        if (atomic_read(&temp_st->common_attributes.data_ready))
 134                iio_push_to_buffers_with_timestamp(indio_dev, &temp_st->scan,
 135                                                   iio_get_time_ns(indio_dev));
 136
 137        return 0;
 138}
 139
 140/* Capture samples in local storage */
 141static int temperature_capture_sample(struct hid_sensor_hub_device *hsdev,
 142                                unsigned int usage_id, size_t raw_len,
 143                                char *raw_data, void *pdev)
 144{
 145        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 146        struct temperature_state *temp_st = iio_priv(indio_dev);
 147
 148        switch (usage_id) {
 149        case HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE:
 150                temp_st->scan.temperature_data = *(s32 *)raw_data;
 151                return 0;
 152        default:
 153                return -EINVAL;
 154        }
 155}
 156
 157/* Parse report which is specific to an usage id*/
 158static int temperature_parse_report(struct platform_device *pdev,
 159                                struct hid_sensor_hub_device *hsdev,
 160                                struct iio_chan_spec *channels,
 161                                unsigned int usage_id,
 162                                struct temperature_state *st)
 163{
 164        int ret;
 165
 166        ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 167                        usage_id,
 168                        HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
 169                        &st->temperature_attr);
 170        if (ret < 0)
 171                return ret;
 172
 173        temperature_adjust_channel_bit_mask(channels, 0,
 174                                        st->temperature_attr.size);
 175
 176        st->scale_precision = hid_sensor_format_scale(
 177                                HID_USAGE_SENSOR_TEMPERATURE,
 178                                &st->temperature_attr,
 179                                &st->scale_pre_decml, &st->scale_post_decml);
 180
 181        return ret;
 182}
 183
 184static struct hid_sensor_hub_callbacks temperature_callbacks = {
 185        .send_event = &temperature_proc_event,
 186        .capture_sample = &temperature_capture_sample,
 187};
 188
 189/* Function to initialize the processing for usage id */
 190static int hid_temperature_probe(struct platform_device *pdev)
 191{
 192        static const char *name = "temperature";
 193        struct iio_dev *indio_dev;
 194        struct temperature_state *temp_st;
 195        struct iio_chan_spec *temp_chans;
 196        struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 197        int ret;
 198
 199        indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*temp_st));
 200        if (!indio_dev)
 201                return -ENOMEM;
 202
 203        temp_st = iio_priv(indio_dev);
 204        temp_st->common_attributes.hsdev = hsdev;
 205        temp_st->common_attributes.pdev = pdev;
 206
 207        ret = hid_sensor_parse_common_attributes(hsdev,
 208                                        HID_USAGE_SENSOR_TEMPERATURE,
 209                                        &temp_st->common_attributes,
 210                                        temperature_sensitivity_addresses,
 211                                        ARRAY_SIZE(temperature_sensitivity_addresses));
 212        if (ret)
 213                return ret;
 214
 215        temp_chans = devm_kmemdup(&indio_dev->dev, temperature_channels,
 216                                sizeof(temperature_channels), GFP_KERNEL);
 217        if (!temp_chans)
 218                return -ENOMEM;
 219
 220        ret = temperature_parse_report(pdev, hsdev, temp_chans,
 221                                HID_USAGE_SENSOR_TEMPERATURE, temp_st);
 222        if (ret)
 223                return ret;
 224
 225        indio_dev->channels = temp_chans;
 226        indio_dev->num_channels = ARRAY_SIZE(temperature_channels);
 227        indio_dev->info = &temperature_info;
 228        indio_dev->name = name;
 229        indio_dev->modes = INDIO_DIRECT_MODE;
 230
 231        atomic_set(&temp_st->common_attributes.data_ready, 0);
 232
 233        ret = hid_sensor_setup_trigger(indio_dev, name,
 234                                &temp_st->common_attributes);
 235        if (ret)
 236                return ret;
 237
 238        platform_set_drvdata(pdev, indio_dev);
 239
 240        temperature_callbacks.pdev = pdev;
 241        ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE,
 242                                        &temperature_callbacks);
 243        if (ret)
 244                goto error_remove_trigger;
 245
 246        ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
 247        if (ret)
 248                goto error_remove_callback;
 249
 250        return ret;
 251
 252error_remove_callback:
 253        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 254error_remove_trigger:
 255        hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
 256        return ret;
 257}
 258
 259/* Function to deinitialize the processing for usage id */
 260static int hid_temperature_remove(struct platform_device *pdev)
 261{
 262        struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 263        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 264        struct temperature_state *temp_st = iio_priv(indio_dev);
 265
 266        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 267        hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
 268
 269        return 0;
 270}
 271
 272static const struct platform_device_id hid_temperature_ids[] = {
 273        {
 274                /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 275                .name = "HID-SENSOR-200033",
 276        },
 277        { /* sentinel */ }
 278};
 279MODULE_DEVICE_TABLE(platform, hid_temperature_ids);
 280
 281static struct platform_driver hid_temperature_platform_driver = {
 282        .id_table = hid_temperature_ids,
 283        .driver = {
 284                .name   = "temperature-sensor",
 285                .pm     = &hid_sensor_pm_ops,
 286        },
 287        .probe          = hid_temperature_probe,
 288        .remove         = hid_temperature_remove,
 289};
 290module_platform_driver(hid_temperature_platform_driver);
 291
 292MODULE_DESCRIPTION("HID Environmental temperature sensor");
 293MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
 294MODULE_LICENSE("GPL v2");
 295MODULE_IMPORT_NS(IIO_HID);
 296