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 static const u32 temperature_sensitivity_addresses[] = {
  29         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  30 };
  31
  32 /* Channel definitions */
  33 static const struct iio_chan_spec temperature_channels[] = {
  34         {
  35                 .type = IIO_TEMP,
  36                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  37                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  38                         BIT(IIO_CHAN_INFO_SCALE) |
  39                         BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  40                         BIT(IIO_CHAN_INFO_HYSTERESIS),
  41         },
  42         IIO_CHAN_SOFT_TIMESTAMP(1),
  43 };
  44
  45 /* Adjust channel real bits based on report descriptor */
  46 static void temperature_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  47                                         int channel, int size)
  48 {
  49         channels[channel].scan_type.sign = 's';
  50         /* Real storage bits will change based on the report desc. */
  51         channels[channel].scan_type.realbits = size * 8;
  52         /* Maximum size of a sample to capture is s32 */
  53         channels[channel].scan_type.storagebits = sizeof(s32) * 8;
  54 }
  55
  56 static int temperature_read_raw(struct iio_dev *indio_dev,
  57                                 struct iio_chan_spec const *chan,
  58                                 int *val, int *val2, long mask)
  59 {
  60         struct temperature_state *temp_st = iio_priv(indio_dev);
  61
  62         switch (mask) {
  63         case IIO_CHAN_INFO_RAW:
  64                 if (chan->type != IIO_TEMP)
  65                         return -EINVAL;
  66                 hid_sensor_power_state(
  67                         &temp_st->common_attributes, true);
  68                 *val = sensor_hub_input_attr_get_raw_value(
  69                         temp_st->common_attributes.hsdev,
  70                         HID_USAGE_SENSOR_TEMPERATURE,
  71                         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
  72                         temp_st->temperature_attr.report_id,
  73                         SENSOR_HUB_SYNC,
  74                         temp_st->temperature_attr.logical_minimum < 0);
  75                 hid_sensor_power_state(
  76                                 &temp_st->common_attributes,
  77                                 false);
  78
  79                 return IIO_VAL_INT;
  80
  81         case IIO_CHAN_INFO_SCALE:
  82                 *val = temp_st->scale_pre_decml;
  83                 *val2 = temp_st->scale_post_decml;
  84                 return temp_st->scale_precision;
  85
  86         case IIO_CHAN_INFO_OFFSET:
  87                 *val = temp_st->value_offset;
  88                 return IIO_VAL_INT;
  89
  90         case IIO_CHAN_INFO_SAMP_FREQ:
  91                 return hid_sensor_read_samp_freq_value(
  92                                 &temp_st->common_attributes, val, val2);
  93
  94         case IIO_CHAN_INFO_HYSTERESIS:
  95                 return hid_sensor_read_raw_hyst_value(
  96                                 &temp_st->common_attributes, val, val2);
  97         default:
  98                 return -EINVAL;
  99         }
 100 }
 101
 102 static int temperature_write_raw(struct iio_dev *indio_dev,
 103                                 struct iio_chan_spec const *chan,
 104                                 int val, int val2, long mask)
 105 {
 106         struct temperature_state *temp_st = iio_priv(indio_dev);
 107
 108         switch (mask) {
 109         case IIO_CHAN_INFO_SAMP_FREQ:
 110                 return hid_sensor_write_samp_freq_value(
 111                                 &temp_st->common_attributes, val, val2);
 112         case IIO_CHAN_INFO_HYSTERESIS:
 113                 return hid_sensor_write_raw_hyst_value(
 114                                 &temp_st->common_attributes, val, val2);
 115         default:
 116                 return -EINVAL;
 117         }
 118 }
 119
 120 static const struct iio_info temperature_info = {
 121         .read_raw = &temperature_read_raw,
 122         .write_raw = &temperature_write_raw,
 123 };
 124
 125 /* Callback handler to send event after all samples are received and captured */
 126 static int temperature_proc_event(struct hid_sensor_hub_device *hsdev,
 127                                 unsigned int usage_id, void *pdev)
 128 {
 129         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 130         struct temperature_state *temp_st = iio_priv(indio_dev);
 131
 132         if (atomic_read(&temp_st->common_attributes.data_ready))
 133                 iio_push_to_buffers_with_timestamp(indio_dev, &temp_st->scan,
 134                                                    iio_get_time_ns(indio_dev));
 135
 136         return 0;
 137 }
 138
 139 /* Capture samples in local storage */
 140 static int temperature_capture_sample(struct hid_sensor_hub_device *hsdev,
 141                                 unsigned int usage_id, size_t raw_len,
 142                                 char *raw_data, void *pdev)
 143 {
 144         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 145         struct temperature_state *temp_st = iio_priv(indio_dev);
 146
 147         switch (usage_id) {
 148         case HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE:
 149                 temp_st->scan.temperature_data = *(s32 *)raw_data;
 150                 return 0;
 151         default:
 152                 return -EINVAL;
 153         }
 154 }
 155
 156 /* Parse report which is specific to an usage id*/
 157 static int temperature_parse_report(struct platform_device *pdev,
 158                                 struct hid_sensor_hub_device *hsdev,
 159                                 struct iio_chan_spec *channels,
 160                                 unsigned int usage_id,
 161                                 struct temperature_state *st)
 162 {
 163         int ret;
 164
 165         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 166                         usage_id,
 167                         HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
 168                         &st->temperature_attr);
 169         if (ret < 0)
 170                 return ret;
 171
 172         temperature_adjust_channel_bit_mask(channels, 0,
 173                                         st->temperature_attr.size);
 174
 175         st->scale_precision = hid_sensor_format_scale(
 176                                 HID_USAGE_SENSOR_TEMPERATURE,
 177                                 &st->temperature_attr,
 178                                 &st->scale_pre_decml, &st->scale_post_decml);
 179
 180         return ret;
 181 }
 182
 183 static struct hid_sensor_hub_callbacks temperature_callbacks = {
 184         .send_event = &temperature_proc_event,
 185         .capture_sample = &temperature_capture_sample,
 186 };
 187
 188 /* Function to initialize the processing for usage id */
 189 static int hid_temperature_probe(struct platform_device *pdev)
 190 {
 191         static const char *name = "temperature";
 192         struct iio_dev *indio_dev;
 193         struct temperature_state *temp_st;
 194         struct iio_chan_spec *temp_chans;
 195         struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 196         int ret;
 197
 198         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*temp_st));
 199         if (!indio_dev)
 200                 return -ENOMEM;
 201
 202         temp_st = iio_priv(indio_dev);
 203         temp_st->common_attributes.hsdev = hsdev;
 204         temp_st->common_attributes.pdev = pdev;
 205
 206         ret = hid_sensor_parse_common_attributes(hsdev,
 207                                         HID_USAGE_SENSOR_TEMPERATURE,
 208                                         &temp_st->common_attributes,
 209                                         temperature_sensitivity_addresses,
 210                                         ARRAY_SIZE(temperature_sensitivity_addresses));
 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");