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/iio/triggered_buffer.h>
  11 #include <linux/iio/trigger_consumer.h>
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14
  15 #include "../common/hid-sensors/hid-sensor-trigger.h"
  16
  17 struct temperature_state {
  18         struct hid_sensor_common common_attributes;
  19         struct hid_sensor_hub_attribute_info temperature_attr;
  20         s32 temperature_data;
  21         int scale_pre_decml;
  22         int scale_post_decml;
  23         int scale_precision;
  24         int value_offset;
  25 };
  26
  27 /* Channel definitions */
  28 static const struct iio_chan_spec temperature_channels[] = {
  29         {
  30                 .type = IIO_TEMP,
  31                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  32                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  33                         BIT(IIO_CHAN_INFO_SCALE) |
  34                         BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  35                         BIT(IIO_CHAN_INFO_HYSTERESIS),
  36         },
  37         IIO_CHAN_SOFT_TIMESTAMP(3),
  38 };
  39
  40 /* Adjust channel real bits based on report descriptor */
  41 static void temperature_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  42                                         int channel, int size)
  43 {
  44         channels[channel].scan_type.sign = 's';
  45         /* Real storage bits will change based on the report desc. */
  46         channels[channel].scan_type.realbits = size * 8;
  47         /* Maximum size of a sample to capture is s32 */
  48         channels[channel].scan_type.storagebits = sizeof(s32) * 8;
  49 }
  50
  51 static int temperature_read_raw(struct iio_dev *indio_dev,
  52                                 struct iio_chan_spec const *chan,
  53                                 int *val, int *val2, long mask)
  54 {
  55         struct temperature_state *temp_st = iio_priv(indio_dev);
  56
  57         switch (mask) {
  58         case IIO_CHAN_INFO_RAW:
  59                 if (chan->type != IIO_TEMP)
  60                         return -EINVAL;
  61                 hid_sensor_power_state(
  62                         &temp_st->common_attributes, true);
  63                 *val = sensor_hub_input_attr_get_raw_value(
  64                         temp_st->common_attributes.hsdev,
  65                         HID_USAGE_SENSOR_TEMPERATURE,
  66                         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  67                         temp_st->temperature_attr.report_id,
  68                         SENSOR_HUB_SYNC,
  69                         temp_st->temperature_attr.logical_minimum < 0);
  70                 hid_sensor_power_state(
  71                                 &temp_st->common_attributes,
  72                                 false);
  73
  74                 return IIO_VAL_INT;
  75
  76         case IIO_CHAN_INFO_SCALE:
  77                 *val = temp_st->scale_pre_decml;
  78                 *val2 = temp_st->scale_post_decml;
  79                 return temp_st->scale_precision;
  80
  81         case IIO_CHAN_INFO_OFFSET:
  82                 *val = temp_st->value_offset;
  83                 return IIO_VAL_INT;
  84
  85         case IIO_CHAN_INFO_SAMP_FREQ:
  86                 return hid_sensor_read_samp_freq_value(
  87                                 &temp_st->common_attributes, val, val2);
  88
  89         case IIO_CHAN_INFO_HYSTERESIS:
  90                 return hid_sensor_read_raw_hyst_value(
  91                                 &temp_st->common_attributes, val, val2);
  92         default:
  93                 return -EINVAL;
  94         }
  95 }
  96
  97 static int temperature_write_raw(struct iio_dev *indio_dev,
  98                                 struct iio_chan_spec const *chan,
  99                                 int val, int val2, long mask)
 100 {
 101         struct temperature_state *temp_st = iio_priv(indio_dev);
 102
 103         switch (mask) {
 104         case IIO_CHAN_INFO_SAMP_FREQ:
 105                 return hid_sensor_write_samp_freq_value(
 106                                 &temp_st->common_attributes, val, val2);
 107         case IIO_CHAN_INFO_HYSTERESIS:
 108                 return hid_sensor_write_raw_hyst_value(
 109                                 &temp_st->common_attributes, val, val2);
 110         default:
 111                 return -EINVAL;
 112         }
 113 }
 114
 115 static const struct iio_info temperature_info = {
 116         .read_raw = &temperature_read_raw,
 117         .write_raw = &temperature_write_raw,
 118 };
 119
 120 /* Callback handler to send event after all samples are received and captured */
 121 static int temperature_proc_event(struct hid_sensor_hub_device *hsdev,
 122                                 unsigned int usage_id, void *pdev)
 123 {
 124         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 125         struct temperature_state *temp_st = iio_priv(indio_dev);
 126
 127         if (atomic_read(&temp_st->common_attributes.data_ready))
 128                 iio_push_to_buffers_with_timestamp(indio_dev,
 129                                 &temp_st->temperature_data,
 130                                 iio_get_time_ns(indio_dev));
 131
 132         return 0;
 133 }
 134
 135 /* Capture samples in local storage */
 136 static int temperature_capture_sample(struct hid_sensor_hub_device *hsdev,
 137                                 unsigned int usage_id, size_t raw_len,
 138                                 char *raw_data, void *pdev)
 139 {
 140         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 141         struct temperature_state *temp_st = iio_priv(indio_dev);
 142
 143         switch (usage_id) {
 144         case HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE:
 145                 temp_st->temperature_data = *(s32 *)raw_data;
 146                 return 0;
 147         default:
 148                 return -EINVAL;
 149         }
 150 }
 151
 152 /* Parse report which is specific to an usage id*/
 153 static int temperature_parse_report(struct platform_device *pdev,
 154                                 struct hid_sensor_hub_device *hsdev,
 155                                 struct iio_chan_spec *channels,
 156                                 unsigned int usage_id,
 157                                 struct temperature_state *st)
 158 {
 159         int ret;
 160
 161         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 162                         usage_id,
 163                         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
 164                         &st->temperature_attr);
 165         if (ret < 0)
 166                 return ret;
 167
 168         temperature_adjust_channel_bit_mask(channels, 0,
 169                                         st->temperature_attr.size);
 170
 171         st->scale_precision = hid_sensor_format_scale(
 172                                 HID_USAGE_SENSOR_TEMPERATURE,
 173                                 &st->temperature_attr,
 174                                 &st->scale_pre_decml, &st->scale_post_decml);
 175
 176         /* Set Sensitivity field ids, when there is no individual modifier */
 177         if (st->common_attributes.sensitivity.index < 0)
 178                 sensor_hub_input_get_attribute_info(hsdev,
 179                         HID_FEATURE_REPORT, usage_id,
 180                         HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 181                         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
 182                         &st->common_attributes.sensitivity);
 183
 184         return ret;
 185 }
 186
 187 static struct hid_sensor_hub_callbacks temperature_callbacks = {
 188         .send_event = &temperature_proc_event,
 189         .capture_sample = &temperature_capture_sample,
 190 };
 191
 192 /* Function to initialize the processing for usage id */
 193 static int hid_temperature_probe(struct platform_device *pdev)
 194 {
 195         static const char *name = "temperature";
 196         struct iio_dev *indio_dev;
 197         struct temperature_state *temp_st;
 198         struct iio_chan_spec *temp_chans;
 199         struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 200         int ret;
 201
 202         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*temp_st));
 203         if (!indio_dev)
 204                 return -ENOMEM;
 205
 206         temp_st = iio_priv(indio_dev);
 207         temp_st->common_attributes.hsdev = hsdev;
 208         temp_st->common_attributes.pdev = pdev;
 209
 210         ret = hid_sensor_parse_common_attributes(hsdev,
 211                                         HID_USAGE_SENSOR_TEMPERATURE,
 212                                         &temp_st->common_attributes);
 213         if (ret)
 214                 return ret;
 215
 216         temp_chans = devm_kmemdup(&indio_dev->dev, temperature_channels,
 217                                 sizeof(temperature_channels), GFP_KERNEL);
 218         if (!temp_chans)
 219                 return -ENOMEM;
 220
 221         ret = temperature_parse_report(pdev, hsdev, temp_chans,
 222                                 HID_USAGE_SENSOR_TEMPERATURE, temp_st);
 223         if (ret)
 224                 return ret;
 225
 226         indio_dev->channels = temp_chans;
 227         indio_dev->num_channels = ARRAY_SIZE(temperature_channels);
 228         indio_dev->dev.parent = &pdev->dev;
 229         indio_dev->info = &temperature_info;
 230         indio_dev->name = name;
 231         indio_dev->modes = INDIO_DIRECT_MODE;
 232
 233         ret = devm_iio_triggered_buffer_setup(&pdev->dev, indio_dev,
 234                                         &iio_pollfunc_store_time, NULL, NULL);
 235         if (ret)
 236                 return ret;
 237
 238         atomic_set(&temp_st->common_attributes.data_ready, 0);
 239         ret = hid_sensor_setup_trigger(indio_dev, name,
 240                                 &temp_st->common_attributes);
 241         if (ret)
 242                 return ret;
 243
 244         platform_set_drvdata(pdev, indio_dev);
 245
 246         temperature_callbacks.pdev = pdev;
 247         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE,
 248                                         &temperature_callbacks);
 249         if (ret)
 250                 goto error_remove_trigger;
 251
 252         ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
 253         if (ret)
 254                 goto error_remove_callback;
 255
 256         return ret;
 257
 258 error_remove_callback:
 259         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 260 error_remove_trigger:
 261         hid_sensor_remove_trigger(&temp_st->common_attributes);
 262         return ret;
 263 }
 264
 265 /* Function to deinitialize the processing for usage id */
 266 static int hid_temperature_remove(struct platform_device *pdev)
 267 {
 268         struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 269         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 270         struct temperature_state *temp_st = iio_priv(indio_dev);
 271
 272         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 273         hid_sensor_remove_trigger(&temp_st->common_attributes);
 274
 275         return 0;
 276 }
 277
 278 static const struct platform_device_id hid_temperature_ids[] = {
 279         {
 280                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 281                 .name = "HID-SENSOR-200033",
 282         },
 283         { /* sentinel */ }
 284 };
 285 MODULE_DEVICE_TABLE(platform, hid_temperature_ids);
 286
 287 static struct platform_driver hid_temperature_platform_driver = {
 288         .id_table = hid_temperature_ids,
 289         .driver = {
 290                 .name   = "temperature-sensor",
 291                 .pm     = &hid_sensor_pm_ops,
 292         },
 293         .probe          = hid_temperature_probe,
 294         .remove         = hid_temperature_remove,
 295 };
 296 module_platform_driver(hid_temperature_platform_driver);
 297
 298 MODULE_DESCRIPTION("HID Environmental temperature sensor");
 299 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
 300 MODULE_LICENSE("GPL v2");