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, s16 *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 = (s16)be16_to_cpup(raw); 35 /* 36 * Temperature data is invalid if both accel and gyro are off. 37 * Return -EBUSY in this case. 38 */ 39 if (*temp == INV_ICM42600_DATA_INVALID) 40 ret = -EBUSY; 41 42 exit: 43 mutex_unlock(&st->lock); 44 pm_runtime_put_autosuspend(dev); 45 46 return ret; 47 } 48 49 int inv_icm42600_temp_read_raw(struct iio_dev *indio_dev, 50 struct iio_chan_spec const *chan, 51 int *val, int *val2, long mask) 52 { 53 struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev); 54 s16 temp; 55 int ret; 56 57 if (chan->type != IIO_TEMP) 58 return -EINVAL; 59 60 switch (mask) { 61 case IIO_CHAN_INFO_RAW: 62 if (!iio_device_claim_direct(indio_dev)) 63 return -EBUSY; 64 ret = inv_icm42600_temp_read(st, &temp); 65 iio_device_release_direct(indio_dev); 66 if (ret) 67 return ret; 68 *val = temp; 69 return IIO_VAL_INT; 70 /* 71 * T°C = (temp / 132.48) + 25 72 * Tm°C = 1000 * ((temp / 132.48) + 25) 73 * Tm°C = 7.548309 * temp + 25000 74 * Tm°C = (temp + 3312) * 7.548309 75 * scale: 100000 / 13248 ~= 7.548309 76 * offset: 3312 77 */ 78 case IIO_CHAN_INFO_SCALE: 79 *val = 7; 80 *val2 = 548309; 81 return IIO_VAL_INT_PLUS_MICRO; 82 case IIO_CHAN_INFO_OFFSET: 83 *val = 3312; 84 return IIO_VAL_INT; 85 default: 86 return -EINVAL; 87 } 88 } 89