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
  16 struct 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
  29 static const u32 temperature_sensitivity_addresses[] = {
  30         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  31 };
  32
  33 /* Channel definitions */
  34 static 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 */
  47 static 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
  57 static 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
 103 static 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
 121 static 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 */
 127 static 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 */
 141 static 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*/
 158 static 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
 184 static 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 */
 190 static 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
 252 error_remove_callback:
 253         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 254 error_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 */
 260 static 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
 272 static 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 };
 279 MODULE_DEVICE_TABLE(platform, hid_temperature_ids);
 280
 281 static 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 };
 290 module_platform_driver(hid_temperature_platform_driver);
 291
 292 MODULE_DESCRIPTION("HID Environmental temperature sensor");
 293 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
 294 MODULE_LICENSE("GPL v2");
 295 MODULE_IMPORT_NS(IIO_HID);