diff options
Diffstat (limited to 'app/drivers/sensor/battery')
-rw-r--r-- | app/drivers/sensor/battery/CMakeLists.txt | 10 | ||||
-rw-r--r-- | app/drivers/sensor/battery/Kconfig | 21 | ||||
-rw-r--r-- | app/drivers/sensor/battery/battery_common.c | 43 | ||||
-rw-r--r-- | app/drivers/sensor/battery/battery_common.h | 21 | ||||
-rw-r--r-- | app/drivers/sensor/battery/battery_nrf_vddh.c | 116 | ||||
-rw-r--r-- | app/drivers/sensor/battery/battery_voltage_divider.c | 193 |
6 files changed, 404 insertions, 0 deletions
diff --git a/app/drivers/sensor/battery/CMakeLists.txt b/app/drivers/sensor/battery/CMakeLists.txt new file mode 100644 index 0000000..1203e53 --- /dev/null +++ b/app/drivers/sensor/battery/CMakeLists.txt @@ -0,0 +1,10 @@ +# Copyright (c) 2020-2021 The ZMK Contributors +# SPDX-License-Identifier: MIT + +zephyr_include_directories(.) + +zephyr_library() + +zephyr_library_sources(battery_common.c) +zephyr_library_sources_ifdef(CONFIG_ZMK_BATTERY_NRF_VDDH battery_nrf_vddh.c) +zephyr_library_sources_ifdef(CONFIG_ZMK_BATTERY_VOLTAGE_DIVIDER battery_voltage_divider.c)
\ No newline at end of file diff --git a/app/drivers/sensor/battery/Kconfig b/app/drivers/sensor/battery/Kconfig new file mode 100644 index 0000000..fd8cd26 --- /dev/null +++ b/app/drivers/sensor/battery/Kconfig @@ -0,0 +1,21 @@ +# Copyright (c) 2020-2021 The ZMK Contributors +# SPDX-License-Identifier: MIT + +config ZMK_BATTERY + bool "ZMK battery monitoring" + help + Enable battery monitoring + +config ZMK_BATTERY_NRF_VDDH + bool "ZMK nRF VDDH battery monitoring" + select ADC + select ZMK_BATTERY + help + Enable ZMK nRF VDDH voltage driver for battery monitoring. + +config ZMK_BATTERY_VOLTAGE_DIVIDER + bool "ZMK battery voltage divider" + select ADC + select ZMK_BATTERY + help + Enable ZMK battery voltage divider driver for battery monitoring. diff --git a/app/drivers/sensor/battery/battery_common.c b/app/drivers/sensor/battery/battery_common.c new file mode 100644 index 0000000..36e98af --- /dev/null +++ b/app/drivers/sensor/battery/battery_common.c @@ -0,0 +1,43 @@ +/* + * Copyright (c) 2021 The ZMK Contributors + * + * SPDX-License-Identifier: MIT + */ + +#include <errno.h> +#include <drivers/sensor.h> + +#include "battery_common.h" + +int battery_channel_get(const struct battery_value *value, enum sensor_channel chan, + struct sensor_value *val_out) { + switch (chan) { + case SENSOR_CHAN_GAUGE_VOLTAGE: + val_out->val1 = value->millivolts / 1000; + val_out->val2 = (value->millivolts % 1000) * 1000U; + break; + + case SENSOR_CHAN_GAUGE_STATE_OF_CHARGE: + val_out->val1 = value->state_of_charge; + val_out->val2 = 0; + break; + + default: + return -ENOTSUP; + } + + return 0; +} + +uint8_t lithium_ion_mv_to_pct(int16_t bat_mv) { + // Simple linear approximation of a battery based off adafruit's discharge graph: + // https://learn.adafruit.com/li-ion-and-lipoly-batteries/voltages + + if (bat_mv >= 4200) { + return 100; + } else if (bat_mv <= 3450) { + return 0; + } + + return bat_mv * 2 / 15 - 459; +}
\ No newline at end of file diff --git a/app/drivers/sensor/battery/battery_common.h b/app/drivers/sensor/battery/battery_common.h new file mode 100644 index 0000000..d81c39e --- /dev/null +++ b/app/drivers/sensor/battery/battery_common.h @@ -0,0 +1,21 @@ +/* + * Copyright (c) 2021 The ZMK Contributors + * + * SPDX-License-Identifier: MIT + */ + +#pragma once + +#include <drivers/sensor.h> +#include <stdint.h> + +struct battery_value { + uint16_t adc_raw; + uint16_t millivolts; + uint8_t state_of_charge; +}; + +int battery_channel_get(const struct battery_value *value, enum sensor_channel chan, + struct sensor_value *val_out); + +uint8_t lithium_ion_mv_to_pct(int16_t bat_mv); diff --git a/app/drivers/sensor/battery/battery_nrf_vddh.c b/app/drivers/sensor/battery/battery_nrf_vddh.c new file mode 100644 index 0000000..9089034 --- /dev/null +++ b/app/drivers/sensor/battery/battery_nrf_vddh.c @@ -0,0 +1,116 @@ +/* + * Copyright (c) 2021 The ZMK Contributors + * + * SPDX-License-Identifier: MIT + * + * This is a simplified version of battery_voltage_divider.c which always reads + * the VDDHDIV5 channel of the &adc node and multiplies it by 5. + */ + +#define DT_DRV_COMPAT zmk_battery_nrf_vddh + +#include <device.h> +#include <devicetree.h> +#include <drivers/adc.h> +#include <drivers/sensor.h> +#include <logging/log.h> + +#include "battery_common.h" + +LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL); + +#define VDDHDIV (5) + +static const struct device *adc = DEVICE_DT_GET(DT_NODELABEL(adc)); + +struct vddh_data { + struct adc_channel_cfg acc; + struct adc_sequence as; + struct battery_value value; +}; + +static int vddh_sample_fetch(const struct device *dev, enum sensor_channel chan) { + // Make sure selected channel is supported + if (chan != SENSOR_CHAN_GAUGE_VOLTAGE && chan != SENSOR_CHAN_GAUGE_STATE_OF_CHARGE && + chan != SENSOR_CHAN_ALL) { + LOG_DBG("Selected channel is not supported: %d.", chan); + return -ENOTSUP; + } + + struct vddh_data *drv_data = dev->data; + struct adc_sequence *as = &drv_data->as; + + int rc = adc_read(adc, as); + as->calibrate = false; + + if (rc != 0) { + LOG_ERR("Failed to read ADC: %d", rc); + return rc; + } + + int32_t val = drv_data->value.adc_raw; + rc = adc_raw_to_millivolts(adc_ref_internal(adc), drv_data->acc.gain, as->resolution, &val); + if (rc != 0) { + LOG_ERR("Failed to convert raw ADC to mV: %d", rc); + return rc; + } + + drv_data->value.millivolts = val * VDDHDIV; + drv_data->value.state_of_charge = lithium_ion_mv_to_pct(drv_data->value.millivolts); + + LOG_DBG("ADC raw %d ~ %d mV => %d%%", drv_data->value.adc_raw, drv_data->value.millivolts, + drv_data->value.state_of_charge); + + return rc; +} + +static int vddh_channel_get(const struct device *dev, enum sensor_channel chan, + struct sensor_value *val) { + struct vddh_data const *drv_data = dev->data; + return battery_channel_get(&drv_data->value, chan, val); +} + +static const struct sensor_driver_api vddh_api = { + .sample_fetch = vddh_sample_fetch, + .channel_get = vddh_channel_get, +}; + +static int vddh_init(const struct device *dev) { + struct vddh_data *drv_data = dev->data; + + if (!device_is_ready(adc)) { + LOG_ERR("ADC device is not ready %s", adc->name); + return -ENODEV; + } + + drv_data->as = (struct adc_sequence){ + .channels = BIT(0), + .buffer = &drv_data->value.adc_raw, + .buffer_size = sizeof(drv_data->value.adc_raw), + .oversampling = 4, + .calibrate = true, + }; + +#ifdef CONFIG_ADC_NRFX_SAADC + drv_data->acc = (struct adc_channel_cfg){ + .gain = ADC_GAIN_1_5, + .reference = ADC_REF_INTERNAL, + .acquisition_time = ADC_ACQ_TIME(ADC_ACQ_TIME_MICROSECONDS, 40), + .input_positive = SAADC_CH_PSELN_PSELN_VDDHDIV5, + }; + + drv_data->as.resolution = 12; +#else +#error Unsupported ADC +#endif + + const int rc = adc_channel_setup(adc, &drv_data->acc); + LOG_DBG("VDDHDIV5 setup returned %d", rc); + + return rc; +} + +static struct vddh_data vddh_data; + +DEVICE_DT_INST_DEFINE(0, &vddh_init, device_pm_control_nop, &vddh_data, NULL, POST_KERNEL, + CONFIG_SENSOR_INIT_PRIORITY, &vddh_api); diff --git a/app/drivers/sensor/battery/battery_voltage_divider.c b/app/drivers/sensor/battery/battery_voltage_divider.c new file mode 100644 index 0000000..8981fb3 --- /dev/null +++ b/app/drivers/sensor/battery/battery_voltage_divider.c @@ -0,0 +1,193 @@ +/* + * Copyright (c) 2020 The ZMK Contributors + * + * SPDX-License-Identifier: MIT + */ + +#define DT_DRV_COMPAT zmk_battery_voltage_divider + +#include <device.h> +#include <devicetree.h> +#include <drivers/gpio.h> +#include <drivers/adc.h> +#include <drivers/sensor.h> +#include <logging/log.h> + +#include "battery_common.h" + +LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL); + +struct io_channel_config { + const char *label; + uint8_t channel; +}; + +struct gpio_channel_config { + const char *label; + uint8_t pin; + uint8_t flags; +}; + +struct bvd_config { + struct io_channel_config io_channel; + struct gpio_channel_config power_gpios; + uint32_t output_ohm; + uint32_t full_ohm; +}; + +struct bvd_data { + const struct device *adc; + const struct device *gpio; + struct adc_channel_cfg acc; + struct adc_sequence as; + struct battery_value value; +}; + +static int bvd_sample_fetch(const struct device *dev, enum sensor_channel chan) { + struct bvd_data *drv_data = dev->data; + const struct bvd_config *drv_cfg = dev->config; + struct adc_sequence *as = &drv_data->as; + + // Make sure selected channel is supported + if (chan != SENSOR_CHAN_GAUGE_VOLTAGE && chan != SENSOR_CHAN_GAUGE_STATE_OF_CHARGE && + chan != SENSOR_CHAN_ALL) { + LOG_DBG("Selected channel is not supported: %d.", chan); + return -ENOTSUP; + } + + int rc = 0; + + // Enable power GPIO if present + if (drv_data->gpio) { + rc = gpio_pin_set(drv_data->gpio, drv_cfg->power_gpios.pin, 1); + + if (rc != 0) { + LOG_DBG("Failed to enable ADC power GPIO: %d", rc); + return rc; + } + + // wait for any capacitance to charge up + k_sleep(K_MSEC(10)); + } + + // Read ADC + rc = adc_read(drv_data->adc, as); + as->calibrate = false; + + if (rc == 0) { + int32_t val = drv_data->value.adc_raw; + + adc_raw_to_millivolts(adc_ref_internal(drv_data->adc), drv_data->acc.gain, as->resolution, + &val); + + uint16_t millivolts = val * (uint64_t)drv_cfg->full_ohm / drv_cfg->output_ohm; + LOG_DBG("ADC raw %d ~ %d mV => %d mV", drv_data->value.adc_raw, val, millivolts); + uint8_t percent = lithium_ion_mv_to_pct(millivolts); + LOG_DBG("Percent: %d", percent); + + drv_data->value.millivolts = millivolts; + drv_data->value.state_of_charge = percent; + } else { + LOG_DBG("Failed to read ADC: %d", rc); + } + + // Disable power GPIO if present + if (drv_data->gpio) { + int rc2 = gpio_pin_set(drv_data->gpio, drv_cfg->power_gpios.pin, 0); + + if (rc2 != 0) { + LOG_DBG("Failed to disable ADC power GPIO: %d", rc2); + return rc2; + } + } + + return rc; +} + +static int bvd_channel_get(const struct device *dev, enum sensor_channel chan, + struct sensor_value *val) { + struct bvd_data *drv_data = dev->data; + return battery_channel_get(&drv_data->value, chan, val); +} + +static const struct sensor_driver_api bvd_api = { + .sample_fetch = bvd_sample_fetch, + .channel_get = bvd_channel_get, +}; + +static int bvd_init(const struct device *dev) { + struct bvd_data *drv_data = dev->data; + const struct bvd_config *drv_cfg = dev->config; + + drv_data->adc = device_get_binding(drv_cfg->io_channel.label); + + if (drv_data->adc == NULL) { + LOG_ERR("ADC %s failed to retrieve", drv_cfg->io_channel.label); + return -ENODEV; + } + + int rc = 0; + + if (drv_cfg->power_gpios.label) { + drv_data->gpio = device_get_binding(drv_cfg->power_gpios.label); + if (drv_data->gpio == NULL) { + LOG_ERR("Failed to get GPIO %s", drv_cfg->power_gpios.label); + return -ENODEV; + } + rc = gpio_pin_configure(drv_data->gpio, drv_cfg->power_gpios.pin, + GPIO_OUTPUT_INACTIVE | drv_cfg->power_gpios.flags); + if (rc != 0) { + LOG_ERR("Failed to control feed %s.%u: %d", drv_cfg->power_gpios.label, + drv_cfg->power_gpios.pin, rc); + return rc; + } + } + + drv_data->as = (struct adc_sequence){ + .channels = BIT(0), + .buffer = &drv_data->value.adc_raw, + .buffer_size = sizeof(drv_data->value.adc_raw), + .oversampling = 4, + .calibrate = true, + }; + +#ifdef CONFIG_ADC_NRFX_SAADC + drv_data->acc = (struct adc_channel_cfg){ + .gain = ADC_GAIN_1_5, + .reference = ADC_REF_INTERNAL, + .acquisition_time = ADC_ACQ_TIME(ADC_ACQ_TIME_MICROSECONDS, 40), + .input_positive = SAADC_CH_PSELP_PSELP_AnalogInput0 + drv_cfg->io_channel.channel, + }; + + drv_data->as.resolution = 12; +#else +#error Unsupported ADC +#endif + + rc = adc_channel_setup(drv_data->adc, &drv_data->acc); + LOG_DBG("AIN%u setup returned %d", drv_cfg->io_channel.channel, rc); + + return rc; +} + +static struct bvd_data bvd_data; +static const struct bvd_config bvd_cfg = { + .io_channel = + { + DT_INST_IO_CHANNELS_LABEL(0), + DT_INST_IO_CHANNELS_INPUT(0), + }, +#if DT_INST_NODE_HAS_PROP(0, power_gpios) + .power_gpios = + { + DT_INST_GPIO_LABEL(0, power_gpios), + DT_INST_GPIO_PIN(0, power_gpios), + DT_INST_GPIO_FLAGS(0, power_gpios), + }, +#endif + .output_ohm = DT_INST_PROP(0, output_ohms), + .full_ohm = DT_INST_PROP(0, full_ohms), +}; + +DEVICE_DT_INST_DEFINE(0, &bvd_init, device_pm_control_nop, &bvd_data, &bvd_cfg, POST_KERNEL, + CONFIG_SENSOR_INIT_PRIORITY, &bvd_api); |