diff options
Diffstat (limited to 'driver/temp_sensor/thermistor.c')
| -rw-r--r-- | driver/temp_sensor/thermistor.c | 273 |
1 files changed, 0 insertions, 273 deletions
diff --git a/driver/temp_sensor/thermistor.c b/driver/temp_sensor/thermistor.c deleted file mode 100644 index ffa780cb07..0000000000 --- a/driver/temp_sensor/thermistor.c +++ /dev/null @@ -1,273 +0,0 @@ -/* Copyright 2018 The Chromium OS Authors. All rights reserved. - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - */ - -/* - * Common thermistor code for Chrome EC. See ./thermistor.md for table of - * resistance of a 47kΩ B4050 thermistor - */ - -#include "adc.h" -#include "common.h" -#include "gpio.h" -#include "temp_sensor/thermistor.h" -#include "util.h" - -int thermistor_linear_interpolate(uint16_t mv, - const struct thermistor_info *info) -{ - const struct thermistor_data_pair *data = info->data; - int v_high = 0, v_low = 0, t_low, t_high, num_steps; - int head, tail, mid = 0; - - /* We need at least two points to form a line. */ - ASSERT(info->num_pairs >= 2); - - /* - * If input value is out of bounds return the lowest or highest - * value in the data sets provided. - */ - if (mv > data[0].mv * info->scaling_factor) - return data[0].temp; - else if (mv < data[info->num_pairs - 1].mv * info->scaling_factor) - return data[info->num_pairs - 1].temp; - - head = 0; - tail = info->num_pairs - 1; - while (head != tail) { - mid = (head + tail) / 2; - v_high = data[mid].mv * info->scaling_factor; - v_low = data[mid + 1].mv * info->scaling_factor; - - if ((mv <= v_high) && (mv >= v_low)) - break; - else if (mv > v_high) - tail = mid; - else if (mv < v_low) - head = mid + 1; - } - - t_low = data[mid].temp; - t_high = data[mid + 1].temp; - - /* - * The obvious way of doing this is to figure out how many mV per - * degree are in between the two points (mv_per_deg_c), and then how - * many of those exist between the input voltage and voltage of - * lower temperature : - * 1. mv_per_deg_c = (v_high - v_low) / (t_high - t_low) - * 2. num_steps = (v_high - mv) / mv_per_deg_c - * 3. result = t_low + num_steps - * - * Combine #1 and #2 to mitigate precision loss due to integer division. - */ - num_steps = ((v_high - mv) * (t_high - t_low)) / (v_high - v_low); - return t_low + num_steps; -} - -#if defined(CONFIG_STEINHART_HART_3V3_51K1_47K_4050B) || \ - defined(CONFIG_STEINHART_HART_3V3_13K7_47K_4050B) || \ - defined(CONFIG_STEINHART_HART_6V0_51K1_47K_4050B) || \ - defined(CONFIG_STEINHART_HART_3V0_22K6_47K_4050B) || \ - defined(CONFIG_STEINHART_HART_3V3_30K9_47K_4050B) || \ - defined(CONFIG_ZEPHYR) -int thermistor_get_temperature(int idx_adc, int *temp_ptr, - const struct thermistor_info *info) -{ - int mv; - -#ifdef CONFIG_TEMP_SENSOR_POWER_GPIO - /* - * If the power rail for the thermistor circuit is not enabled, then - * need to ignore any ADC measurments. - */ - if (!gpio_get_level(CONFIG_TEMP_SENSOR_POWER_GPIO)) - return EC_ERROR_NOT_POWERED; -#endif /* CONFIG_TEMP_SENSOR_POWER_GPIO */ - mv = adc_read_channel(idx_adc); - if (mv < 0) - return EC_ERROR_UNKNOWN; - - *temp_ptr = thermistor_linear_interpolate(mv, info); - *temp_ptr = C_TO_K(*temp_ptr); - return EC_SUCCESS; -} -#endif - -#ifdef CONFIG_STEINHART_HART_3V3_51K1_47K_4050B -/* - * Data derived from Steinhart-Hart equation in a resistor divider circuit with - * Vdd=3300mV, R = 51.1Kohm, and thermistor (B = 4050, T0 = 298.15 K, nominal - * resistance (R0) = 47Kohm). - */ -#define THERMISTOR_SCALING_FACTOR_51_47 11 -static const struct thermistor_data_pair thermistor_data_51_47[] = { - { 2484 / THERMISTOR_SCALING_FACTOR_51_47, 0 }, - { 2142 / THERMISTOR_SCALING_FACTOR_51_47, 10 }, - { 1767 / THERMISTOR_SCALING_FACTOR_51_47, 20 }, - { 1400 / THERMISTOR_SCALING_FACTOR_51_47, 30 }, - { 1072 / THERMISTOR_SCALING_FACTOR_51_47, 40 }, - { 802 / THERMISTOR_SCALING_FACTOR_51_47, 50 }, - { 593 / THERMISTOR_SCALING_FACTOR_51_47, 60 }, - { 436 / THERMISTOR_SCALING_FACTOR_51_47, 70 }, - { 321 / THERMISTOR_SCALING_FACTOR_51_47, 80 }, - { 276 / THERMISTOR_SCALING_FACTOR_51_47, 85 }, - { 237 / THERMISTOR_SCALING_FACTOR_51_47, 90 }, - { 204 / THERMISTOR_SCALING_FACTOR_51_47, 95 }, - { 177 / THERMISTOR_SCALING_FACTOR_51_47, 100 }, -}; - -static const struct thermistor_info thermistor_info_51_47 = { - .scaling_factor = THERMISTOR_SCALING_FACTOR_51_47, - .num_pairs = ARRAY_SIZE(thermistor_data_51_47), - .data = thermistor_data_51_47, -}; - -int get_temp_3v3_51k1_47k_4050b(int idx_adc, int *temp_ptr) -{ - return thermistor_get_temperature(idx_adc, temp_ptr, - &thermistor_info_51_47); -} -#endif /* CONFIG_STEINHART_HART_3V3_51K1_47K_4050B */ - -#ifdef CONFIG_STEINHART_HART_3V3_13K7_47K_4050B -/* - * Data derived from Steinhart-Hart equation in a resistor divider circuit with - * Vdd=3300mV, R = 13.7Kohm, and thermistor (B = 4050, T0 = 298.15 K, nominal - * resistance (R0) = 47Kohm). - */ -#define THERMISTOR_SCALING_FACTOR_13_47 13 -static const struct thermistor_data_pair thermistor_data_13_47[] = { - { 3033 / THERMISTOR_SCALING_FACTOR_13_47, 0 }, - { 2882 / THERMISTOR_SCALING_FACTOR_13_47, 10 }, - { 2677 / THERMISTOR_SCALING_FACTOR_13_47, 20 }, - { 2420 / THERMISTOR_SCALING_FACTOR_13_47, 30 }, - { 2119 / THERMISTOR_SCALING_FACTOR_13_47, 40 }, - { 1799 / THERMISTOR_SCALING_FACTOR_13_47, 50 }, - { 1485 / THERMISTOR_SCALING_FACTOR_13_47, 60 }, - { 1197 / THERMISTOR_SCALING_FACTOR_13_47, 70 }, - { 947 / THERMISTOR_SCALING_FACTOR_13_47, 80 }, - { 839 / THERMISTOR_SCALING_FACTOR_13_47, 85 }, - { 741 / THERMISTOR_SCALING_FACTOR_13_47, 90 }, - { 653 / THERMISTOR_SCALING_FACTOR_13_47, 95 }, - { 576 / THERMISTOR_SCALING_FACTOR_13_47, 100 }, -}; - -static const struct thermistor_info thermistor_info_13_47 = { - .scaling_factor = THERMISTOR_SCALING_FACTOR_13_47, - .num_pairs = ARRAY_SIZE(thermistor_data_13_47), - .data = thermistor_data_13_47, -}; - -int get_temp_3v3_13k7_47k_4050b(int idx_adc, int *temp_ptr) -{ - return thermistor_get_temperature(idx_adc, temp_ptr, - &thermistor_info_13_47); -} -#endif /* CONFIG_STEINHART_HART_3V3_13K7_47K_4050B */ - -#ifdef CONFIG_STEINHART_HART_6V0_51K1_47K_4050B -/* - * Data derived from Steinhart-Hart equation in a resistor divider circuit with - * Vdd=6000mV, R = 51.1Kohm, and thermistor (B = 4050, T0 = 298.15 K, nominal - * resistance (R0) = 47Kohm). - */ -#define THERMISTOR_SCALING_FACTOR_6V0_51_47 18 -static const struct thermistor_data_pair thermistor_data_6v0_51_47[] = { - { 4517 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 0 }, - { 3895 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 10 }, - { 3214 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 20 }, - { 2546 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 30 }, - { 1950 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 40 }, - { 1459 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 50 }, - { 1079 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 60 }, - { 794 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 70 }, - { 584 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 80 }, - { 502 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 85 }, - { 432 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 90 }, - { 372 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 95 }, - { 322 / THERMISTOR_SCALING_FACTOR_6V0_51_47, 100 }, -}; - -static const struct thermistor_info thermistor_info_6v0_51_47 = { - .scaling_factor = THERMISTOR_SCALING_FACTOR_6V0_51_47, - .num_pairs = ARRAY_SIZE(thermistor_data_6v0_51_47), - .data = thermistor_data_6v0_51_47, -}; - -int get_temp_6v0_51k1_47k_4050b(int idx_adc, int *temp_ptr) -{ - return thermistor_get_temperature(idx_adc, temp_ptr, - &thermistor_info_6v0_51_47); -} -#endif /* CONFIG_STEINHART_HART_6V0_51K1_47K_4050B */ - -#ifdef CONFIG_STEINHART_HART_3V0_22K6_47K_4050B -/* - * Data derived from Steinhart-Hart equation in a resistor divider circuit with - * Vdd=3000mV, R = 22.6Kohm, and thermistor (B = 4050, T0 = 298.15 K, nominal - * resistance (R0) = 47Kohm). - */ -#define THERMISTOR_SCALING_FACTOR_22_47 11 -static const struct thermistor_data_pair thermistor_data_22_47[] = { - { 2619 / THERMISTOR_SCALING_FACTOR_22_47, 0 }, - { 2421 / THERMISTOR_SCALING_FACTOR_22_47, 10 }, - { 2168 / THERMISTOR_SCALING_FACTOR_22_47, 20 }, - { 1875 / THERMISTOR_SCALING_FACTOR_22_47, 30 }, - { 1563 / THERMISTOR_SCALING_FACTOR_22_47, 40 }, - { 1262 / THERMISTOR_SCALING_FACTOR_22_47, 50 }, - { 994 / THERMISTOR_SCALING_FACTOR_22_47, 60 }, - { 769 / THERMISTOR_SCALING_FACTOR_22_47, 70 }, - { 588 / THERMISTOR_SCALING_FACTOR_22_47, 80 }, - { 513 / THERMISTOR_SCALING_FACTOR_22_47, 85 }, - { 448 / THERMISTOR_SCALING_FACTOR_22_47, 90 }, - { 390 / THERMISTOR_SCALING_FACTOR_22_47, 95 }, - { 340 / THERMISTOR_SCALING_FACTOR_22_47, 100 }, -}; - -static const struct thermistor_info thermistor_info_22_47 = { - .scaling_factor = THERMISTOR_SCALING_FACTOR_22_47, - .num_pairs = ARRAY_SIZE(thermistor_data_22_47), - .data = thermistor_data_22_47, -}; - -int get_temp_3v0_22k6_47k_4050b(int idx_adc, int *temp_ptr) -{ - return thermistor_get_temperature(idx_adc, temp_ptr, - &thermistor_info_22_47); -} -#endif /* CONFIG_STEINHART_HART_3V0_22K6_47K_4050B */ - -#ifdef CONFIG_STEINHART_HART_3V3_30K9_47K_4050B -/* - * Data derived from Steinhart-Hart equation in a resistor divider circuit with - * Vdd=3300mV, R = 30.9Kohm, and thermistor (B = 4050, T0 = 298.15 K, nominal - * resistance (R0) = 47Kohm). - */ -#define THERMISTOR_SCALING_FACTOR_31_47 11 -static const struct thermistor_data_pair thermistor_data_31_47[] = { - { 2753 / THERMISTOR_SCALING_FACTOR_31_47, 0 }, - { 2487 / THERMISTOR_SCALING_FACTOR_31_47, 10 }, - { 2165 / THERMISTOR_SCALING_FACTOR_31_47, 20 }, - { 1813 / THERMISTOR_SCALING_FACTOR_31_47, 30 }, - { 1145 / THERMISTOR_SCALING_FACTOR_31_47, 50 }, - { 878 / THERMISTOR_SCALING_FACTOR_31_47, 60 }, - { 665 / THERMISTOR_SCALING_FACTOR_31_47, 70 }, - { 500 / THERMISTOR_SCALING_FACTOR_31_47, 80 }, - { 375 / THERMISTOR_SCALING_FACTOR_31_47, 90 }, - { 282 / THERMISTOR_SCALING_FACTOR_31_47, 100 }, -}; - -static const struct thermistor_info thermistor_info_31_47 = { - .scaling_factor = THERMISTOR_SCALING_FACTOR_31_47, - .num_pairs = ARRAY_SIZE(thermistor_data_31_47), - .data = thermistor_data_31_47, -}; - -int get_temp_3v3_30k9_47k_4050b(int idx_adc, int *temp_ptr) -{ - return thermistor_get_temperature(idx_adc, temp_ptr, - &thermistor_info_31_47); -} -#endif /* CONFIG_STEINHART_HART_3V3_30K9_47K_4050B */ |