drivers/iio/temperature/iqs620at-temp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Azoteq IQS620AT Temperature Sensor
   4  *
   5  * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com>
   6  */
   7
   8 #include <linux/device.h>
   9 #include <linux/iio/iio.h>
  10 #include <linux/kernel.h>
  11 #include <linux/mfd/iqs62x.h>
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/regmap.h>
  15
  16 #define IQS620_TEMP_UI_OUT                      0x1A
  17
  18 #define IQS620_TEMP_SCALE                       1000
  19 #define IQS620_TEMP_OFFSET                      (-100)
  20 #define IQS620_TEMP_OFFSET_V3                   (-40)
  21
  22 static int iqs620_temp_read_raw(struct iio_dev *indio_dev,
  23                                 struct iio_chan_spec const *chan,
  24                                 int *val, int *val2, long mask)
  25 {
  26         struct iqs62x_core *iqs62x = iio_device_get_drvdata(indio_dev);
  27         int ret;
  28         __le16 val_buf;
  29
  30         switch (mask) {
  31         case IIO_CHAN_INFO_RAW:
  32                 ret = regmap_raw_read(iqs62x->regmap, IQS620_TEMP_UI_OUT,
  33                                       &val_buf, sizeof(val_buf));
  34                 if (ret)
  35                         return ret;
  36
  37                 *val = le16_to_cpu(val_buf);
  38                 return IIO_VAL_INT;
  39
  40         case IIO_CHAN_INFO_SCALE:
  41                 *val = IQS620_TEMP_SCALE;
  42                 return IIO_VAL_INT;
  43
  44         case IIO_CHAN_INFO_OFFSET:
  45                 *val = iqs62x->hw_num < IQS620_HW_NUM_V3 ? IQS620_TEMP_OFFSET
  46                                                          : IQS620_TEMP_OFFSET_V3;
  47                 return IIO_VAL_INT;
  48
  49         default:
  50                 return -EINVAL;
  51         }
  52 }
  53
  54 static const struct iio_info iqs620_temp_info = {
  55         .read_raw = &iqs620_temp_read_raw,
  56 };
  57
  58 static const struct iio_chan_spec iqs620_temp_channels[] = {
  59         {
  60                 .type = IIO_TEMP,
  61                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
  62                                       BIT(IIO_CHAN_INFO_SCALE) |
  63                                       BIT(IIO_CHAN_INFO_OFFSET),
  64         },
  65 };
  66
  67 static int iqs620_temp_probe(struct platform_device *pdev)
  68 {
  69         struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent);
  70         struct iio_dev *indio_dev;
  71
  72         indio_dev = devm_iio_device_alloc(&pdev->dev, 0);
  73         if (!indio_dev)
  74                 return -ENOMEM;
  75
  76         iio_device_set_drvdata(indio_dev, iqs62x);
  77
  78         indio_dev->modes = INDIO_DIRECT_MODE;
  79         indio_dev->channels = iqs620_temp_channels;
  80         indio_dev->num_channels = ARRAY_SIZE(iqs620_temp_channels);
  81         indio_dev->name = iqs62x->dev_desc->dev_name;
  82         indio_dev->info = &iqs620_temp_info;
  83
  84         return devm_iio_device_register(&pdev->dev, indio_dev);
  85 }
  86
  87 static struct platform_driver iqs620_temp_platform_driver = {
  88         .driver = {
  89                 .name = "iqs620at-temp",
  90         },
  91         .probe = iqs620_temp_probe,
  92 };
  93 module_platform_driver(iqs620_temp_platform_driver);
  94
  95 MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");
  96 MODULE_DESCRIPTION("Azoteq IQS620AT Temperature Sensor");
  97 MODULE_LICENSE("GPL");
  98 MODULE_ALIAS("platform:iqs620at-temp");