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/platform_device.h>
  12
  13 #include "../common/hid-sensors/hid-sensor-trigger.h"
  14
  15 struct temperature_state {
  16         struct hid_sensor_common common_attributes;
  17         struct hid_sensor_hub_attribute_info temperature_attr;
  18         struct {
  19                 s32 temperature_data;
  20                 u64 timestamp __aligned(8);
  21         } scan;
  22         int scale_pre_decml;
  23         int scale_post_decml;
  24         int scale_precision;
  25         int value_offset;
  26 };
  27
  28 /* Channel definitions */
  29 static const struct iio_chan_spec temperature_channels[] = {
  30         {
  31                 .type = IIO_TEMP,
  32                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  33                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  34                         BIT(IIO_CHAN_INFO_SCALE) |
  35                         BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  36                         BIT(IIO_CHAN_INFO_HYSTERESIS),
  37         },
  38         IIO_CHAN_SOFT_TIMESTAMP(1),
  39 };
  40
  41 /* Adjust channel real bits based on report descriptor */
  42 static void temperature_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  43                                         int channel, int size)
  44 {
  45         channels[channel].scan_type.sign = 's';
  46         /* Real storage bits will change based on the report desc. */
  47         channels[channel].scan_type.realbits = size * 8;
  48         /* Maximum size of a sample to capture is s32 */
  49         channels[channel].scan_type.storagebits = sizeof(s32) * 8;
  50 }
  51
  52 static int temperature_read_raw(struct iio_dev *indio_dev,
  53                                 struct iio_chan_spec const *chan,
  54                                 int *val, int *val2, long mask)
  55 {
  56         struct temperature_state *temp_st = iio_priv(indio_dev);
  57
  58         switch (mask) {
  59         case IIO_CHAN_INFO_RAW:
  60                 if (chan->type != IIO_TEMP)
  61                         return -EINVAL;
  62                 hid_sensor_power_state(
  63                         &temp_st->common_attributes, true);
  64                 *val = sensor_hub_input_attr_get_raw_value(
  65                         temp_st->common_attributes.hsdev,
  66                         HID_USAGE_SENSOR_TEMPERATURE,
  67                         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  68                         temp_st->temperature_attr.report_id,
  69                         SENSOR_HUB_SYNC,
  70                         temp_st->temperature_attr.logical_minimum < 0);
  71                 hid_sensor_power_state(
  72                                 &temp_st->common_attributes,
  73                                 false);
  74
  75                 return IIO_VAL_INT;
  76
  77         case IIO_CHAN_INFO_SCALE:
  78                 *val = temp_st->scale_pre_decml;
  79                 *val2 = temp_st->scale_post_decml;
  80                 return temp_st->scale_precision;
  81
  82         case IIO_CHAN_INFO_OFFSET:
  83                 *val = temp_st->value_offset;
  84                 return IIO_VAL_INT;
  85
  86         case IIO_CHAN_INFO_SAMP_FREQ:
  87                 return hid_sensor_read_samp_freq_value(
  88                                 &temp_st->common_attributes, val, val2);
  89
  90         case IIO_CHAN_INFO_HYSTERESIS:
  91                 return hid_sensor_read_raw_hyst_value(
  92                                 &temp_st->common_attributes, val, val2);
  93         default:
  94                 return -EINVAL;
  95         }
  96 }
  97
  98 static int temperature_write_raw(struct iio_dev *indio_dev,
  99                                 struct iio_chan_spec const *chan,
 100                                 int val, int val2, long mask)
 101 {
 102         struct temperature_state *temp_st = iio_priv(indio_dev);
 103
 104         switch (mask) {
 105         case IIO_CHAN_INFO_SAMP_FREQ:
 106                 return hid_sensor_write_samp_freq_value(
 107                                 &temp_st->common_attributes, val, val2);
 108         case IIO_CHAN_INFO_HYSTERESIS:
 109                 return hid_sensor_write_raw_hyst_value(
 110                                 &temp_st->common_attributes, val, val2);
 111         default:
 112                 return -EINVAL;
 113         }
 114 }
 115
 116 static const struct iio_info temperature_info = {
 117         .read_raw = &temperature_read_raw,
 118         .write_raw = &temperature_write_raw,
 119 };
 120
 121 /* Callback handler to send event after all samples are received and captured */
 122 static int temperature_proc_event(struct hid_sensor_hub_device *hsdev,
 123                                 unsigned int usage_id, void *pdev)
 124 {
 125         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 126         struct temperature_state *temp_st = iio_priv(indio_dev);
 127
 128         if (atomic_read(&temp_st->common_attributes.data_ready))
 129                 iio_push_to_buffers_with_timestamp(indio_dev, &temp_st->scan,
 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->scan.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->info = &temperature_info;
 229         indio_dev->name = name;
 230         indio_dev->modes = INDIO_DIRECT_MODE;
 231
 232         atomic_set(&temp_st->common_attributes.data_ready, 0);
 233
 234         ret = hid_sensor_setup_trigger(indio_dev, name,
 235                                 &temp_st->common_attributes);
 236         if (ret)
 237                 return ret;
 238
 239         platform_set_drvdata(pdev, indio_dev);
 240
 241         temperature_callbacks.pdev = pdev;
 242         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE,
 243                                         &temperature_callbacks);
 244         if (ret)
 245                 goto error_remove_trigger;
 246
 247         ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
 248         if (ret)
 249                 goto error_remove_callback;
 250
 251         return ret;
 252
 253 error_remove_callback:
 254         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 255 error_remove_trigger:
 256         hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
 257         return ret;
 258 }
 259
 260 /* Function to deinitialize the processing for usage id */
 261 static int hid_temperature_remove(struct platform_device *pdev)
 262 {
 263         struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 264         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 265         struct temperature_state *temp_st = iio_priv(indio_dev);
 266
 267         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 268         hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
 269
 270         return 0;
 271 }
 272
 273 static const struct platform_device_id hid_temperature_ids[] = {
 274         {
 275                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 276                 .name = "HID-SENSOR-200033",
 277         },
 278         { /* sentinel */ }
 279 };
 280 MODULE_DEVICE_TABLE(platform, hid_temperature_ids);
 281
 282 static struct platform_driver hid_temperature_platform_driver = {
 283         .id_table = hid_temperature_ids,
 284         .driver = {
 285                 .name   = "temperature-sensor",
 286                 .pm     = &hid_sensor_pm_ops,
 287         },
 288         .probe          = hid_temperature_probe,
 289         .remove         = hid_temperature_remove,
 290 };
 291 module_platform_driver(hid_temperature_platform_driver);
 292
 293 MODULE_DESCRIPTION("HID Environmental temperature sensor");
 294 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
 295 MODULE_LICENSE("GPL v2");