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