drivers/iio/imu/inv_icm42600/inv_icm42600_temp.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2020 Invensense, Inc.
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/device.h>
   8 #include <linux/mutex.h>
   9 #include <linux/pm_runtime.h>
  10 #include <linux/regmap.h>
  11 #include <linux/iio/iio.h>
  12
  13 #include "inv_icm42600.h"
  14 #include "inv_icm42600_temp.h"
  15
  16 static int inv_icm42600_temp_read(struct inv_icm42600_state *st, int16_t *temp)
  17 {
  18         struct device *dev = regmap_get_device(st->map);
  19         __be16 *raw;
  20         int ret;
  21
  22         pm_runtime_get_sync(dev);
  23         mutex_lock(&st->lock);
  24
  25         ret = inv_icm42600_set_temp_conf(st, true, NULL);
  26         if (ret)
  27                 goto exit;
  28
  29         raw = (__be16 *)&st->buffer[0];
  30         ret = regmap_bulk_read(st->map, INV_ICM42600_REG_TEMP_DATA, raw, sizeof(*raw));
  31         if (ret)
  32                 goto exit;
  33
  34         *temp = (int16_t)be16_to_cpup(raw);
  35         if (*temp == INV_ICM42600_DATA_INVALID)
  36                 ret = -EINVAL;
  37
  38 exit:
  39         mutex_unlock(&st->lock);
  40         pm_runtime_mark_last_busy(dev);
  41         pm_runtime_put_autosuspend(dev);
  42
  43         return ret;
  44 }
  45
  46 int inv_icm42600_temp_read_raw(struct iio_dev *indio_dev,
  47                                struct iio_chan_spec const *chan,
  48                                int *val, int *val2, long mask)
  49 {
  50         struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
  51         int16_t temp;
  52         int ret;
  53
  54         if (chan->type != IIO_TEMP)
  55                 return -EINVAL;
  56
  57         switch (mask) {
  58         case IIO_CHAN_INFO_RAW:
  59                 ret = iio_device_claim_direct_mode(indio_dev);
  60                 if (ret)
  61                         return ret;
  62                 ret = inv_icm42600_temp_read(st, &temp);
  63                 iio_device_release_direct_mode(indio_dev);
  64                 if (ret)
  65                         return ret;
  66                 *val = temp;
  67                 return IIO_VAL_INT;
  68         /*
  69          * T°C = (temp / 132.48) + 25
  70          * Tm°C = 1000 * ((temp * 100 / 13248) + 25)
  71          * scale: 100000 / 13248 ~= 7.548309
  72          * offset: 25000
  73          */
  74         case IIO_CHAN_INFO_SCALE:
  75                 *val = 7;
  76                 *val2 = 548309;
  77                 return IIO_VAL_INT_PLUS_MICRO;
  78         case IIO_CHAN_INFO_OFFSET:
  79                 *val = 25000;
  80                 return IIO_VAL_INT;
  81         default:
  82                 return -EINVAL;
  83         }
  84 }