From 3082455aecc98532807aba3226321a94d2ed4b0c Mon Sep 17 00:00:00 2001 From: Nick Date: Fri, 23 Oct 2020 00:45:59 -0500 Subject: [PATCH] Refactor driver to use Sensor API --- .../arm/bluemicro840/bluemicro840_v1.dts | 8 + app/boards/arm/nice_nano/nice_nano.dts | 1 + app/boards/arm/nrfmicro/nrfmicro_13.dts | 8 + app/drivers/zephyr/battery_voltage_divider.c | 187 +++++++++++++----- .../bindings/zmk,battery-voltage-divider.yaml | 5 + 5 files changed, 162 insertions(+), 47 deletions(-) diff --git a/app/boards/arm/bluemicro840/bluemicro840_v1.dts b/app/boards/arm/bluemicro840/bluemicro840_v1.dts index c693662a..ac8ba56e 100644 --- a/app/boards/arm/bluemicro840/bluemicro840_v1.dts +++ b/app/boards/arm/bluemicro840/bluemicro840_v1.dts @@ -29,6 +29,14 @@ }; }; + vbatt { + compatible = "zmk,battery-voltage-divider"; + label = "VOLTAGE_DIVIDER"; + io-channels = <&adc 7>; + output-ohms = <2000000>; + full-ohms = <(2000000 + 806000)>; + }; + }; &gpio0 { diff --git a/app/boards/arm/nice_nano/nice_nano.dts b/app/boards/arm/nice_nano/nice_nano.dts index 18312ecc..72804e3c 100644 --- a/app/boards/arm/nice_nano/nice_nano.dts +++ b/app/boards/arm/nice_nano/nice_nano.dts @@ -31,6 +31,7 @@ vbatt { compatible = "zmk,battery-voltage-divider"; + label = "VOLTAGE_DIVIDER"; io-channels = <&adc 2>; output-ohms = <2000000>; full-ohms = <(2000000 + 806000)>; diff --git a/app/boards/arm/nrfmicro/nrfmicro_13.dts b/app/boards/arm/nrfmicro/nrfmicro_13.dts index 95bd8adc..840014ad 100644 --- a/app/boards/arm/nrfmicro/nrfmicro_13.dts +++ b/app/boards/arm/nrfmicro/nrfmicro_13.dts @@ -26,6 +26,14 @@ }; }; + vbatt { + compatible = "zmk,battery-voltage-divider"; + label = "VOLTAGE_DIVIDER"; + io-channels = <&adc 2>; + output-ohms = <2000000>; + full-ohms = <(2000000 + 820000)>; + }; + }; &gpio0 { diff --git a/app/drivers/zephyr/battery_voltage_divider.c b/app/drivers/zephyr/battery_voltage_divider.c index 34de6cf1..abe7cb5f 100644 --- a/app/drivers/zephyr/battery_voltage_divider.c +++ b/app/drivers/zephyr/battery_voltage_divider.c @@ -16,97 +16,190 @@ LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL); -#if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT) - -#define VBATT DT_PATH(vbatt) - -struct battery_config { - struct device *adc; - struct adc_channel_cfg acc; - struct adc_sequence as; - int16_t adc_raw; +struct io_channel_config { + const char *label; + uint8_t channel; }; -static struct battery_config battery_config; +struct gpio_channel_config { + const char *label; + uint8_t pin; + uint8_t flags; +}; -static int lithium_ion_mv_to_pct(int16_t bat_mv) { +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 { + struct device *adc; + struct device *gpio; + struct adc_channel_cfg acc; + struct adc_sequence as; + uint16_t adc_raw; + uint16_t voltage; + uint8_t state_of_charge; +}; + +static uint8_t lithium_ion_mv_to_pct(int16_t bat_mv) { // Magic function that maps mV to this discharge graph from adafruit: // https://learn.adafruit.com/li-ion-and-lipoly-batteries/voltages return round(106.818 + (-0.032685 - 106.818) / pow(1 + pow(bat_mv / 3679.35, 58.979), 0.347386)); } -static void battery_read(struct k_work *workd) { - struct battery_config *cfg = &battery_config; - struct adc_sequence *as = &cfg->as; +static int bvd_sample_fetch(struct device *dev, enum sensor_channel chan) { + struct bvd_data *drv_data = dev->driver_data; + const struct bvd_config *drv_cfg = dev->config_info; + struct adc_sequence *as = &drv_data->as; - int rc = adc_read(cfg->adc, as); + 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; + } + } + + // Read ADC + rc = adc_read(drv_data->adc, as); as->calibrate = false; + if (rc == 0) { - int32_t val = cfg->adc_raw; + int32_t val = drv_data->adc_raw; - adc_raw_to_millivolts(adc_ref_internal(cfg->adc), cfg->acc.gain, as->resolution, &val); + adc_raw_to_millivolts(adc_ref_internal(drv_data->adc), drv_data->acc.gain, as->resolution, &val); - rc = val * (uint64_t)DT_PROP(VBATT, full_ohms) / DT_PROP(VBATT, output_ohms); - LOG_DBG("ADC raw %d ~ %d mV => %d mV\n", cfg->adc_raw, val, rc); - int percent = lithium_ion_mv_to_pct(rc); + uint16_t millivolts = val * (uint64_t)drv_cfg->full_ohm / drv_cfg->output_ohm; + LOG_DBG("ADC raw %d ~ %d mV => %d mV\n", drv_data->adc_raw, val, millivolts); + uint8_t percent = lithium_ion_mv_to_pct(millivolts); LOG_DBG("Percent: %d", percent); + + drv_data->voltage = millivolts; + drv_data->state_of_charge = percent; } else { LOG_DBG("Failed to read ADC: %d", rc); } + + // Disable power GPIO if present + if (drv_data->gpio) { + rc = gpio_pin_set(drv_data->gpio, drv_cfg->power_gpios.pin, 0); + + if (rc != 0) { + LOG_DBG("Failed to disable ADC power GPIO: %d", rc); + } + } + + return rc; } -K_WORK_DEFINE(battery_work, battery_read); +static int bvd_channel_get(struct device *dev, enum sensor_channel chan, + struct sensor_value *val) { + struct bvd_data *drv_data = dev->driver_data; -static void battery_handler(struct k_timer *timer) { k_work_submit(&battery_work); } + switch(chan) { + case SENSOR_CHAN_GAUGE_VOLTAGE: + val->val1 = drv_data->voltage / 1000; + val->val2 = (drv_data->voltage % 1000) * 1000U; + break; -K_TIMER_DEFINE(battery_tick, battery_handler, NULL); + case SENSOR_CHAN_GAUGE_STATE_OF_CHARGE: + val->val1 = drv_data->state_of_charge; + val->val2 = 0; + break; -static int battery_setup(struct device *_arg) { - struct battery_config *cfg = &battery_config; - struct adc_sequence *as = &cfg->as; - struct adc_channel_cfg *acc = &cfg->acc; + default: + return -ENOTSUP; + } - cfg->adc = device_get_binding(DT_IO_CHANNELS_LABEL(VBATT)); + return 0; +} - if (cfg->adc == NULL) { - LOG_ERR("ADC %s failed to retrieve", DT_IO_CHANNELS_LABEL(VBATT)); +static const struct sensor_driver_api bvd_api = { + .sample_fetch = bvd_sample_fetch, + .channel_get = bvd_channel_get, +}; + + +static int bvd_init(struct device *dev) { + struct bvd_data *drv_data = dev->driver_data; + const struct bvd_config *drv_cfg = dev->config_info; + + 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 -ENOENT; } - *as = (struct adc_sequence){ + 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 -ENOENT; + } + 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 = &cfg->adc_raw, - .buffer_size = sizeof(cfg->adc_raw), + .buffer = &drv_data->adc_raw, + .buffer_size = sizeof(drv_data->adc_raw), .oversampling = 4, .calibrate = true, }; #ifdef CONFIG_ADC_NRFX_SAADC - *acc = (struct adc_channel_cfg){ + 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 + DT_IO_CHANNELS_INPUT(VBATT), + .input_positive = SAADC_CH_PSELP_PSELP_AnalogInput0 + drv_cfg->io_channel.channel, }; - as->resolution = 12; + drv_data->as.resolution = 12; #else #error Unsupported ADC #endif - int adc_rc = adc_channel_setup(cfg->adc, acc); - LOG_DBG("AIN%u setup returned %d", DT_IO_CHANNELS_INPUT(VBATT), adc_rc); + rc = adc_channel_setup(drv_data->adc, &drv_data->acc); + LOG_DBG("AIN%u setup returned %d", drv_cfg->io_channel.channel, rc); - if (adc_rc != 0) { - return adc_rc; - } - - k_timer_start(&battery_tick, K_NO_WAIT, K_SECONDS(5)); - - return 0; + return rc; } -SYS_INIT(battery_setup, APPLICATION, CONFIG_APPLICATION_INIT_PRIORITY); +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_PIN(0, power_gpios), + DT_INST_FLAGS(0, power_gpios), + }, +#endif + .output_ohm = DT_INST_PROP(0, output_ohms), + .full_ohm = DT_INST_PROP(0, full_ohms), +}; -#endif /* DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT) */ \ No newline at end of file +DEVICE_AND_API_INIT(bvd_dev, DT_INST_LABEL(0), &bvd_init, + &bvd_data, &bvd_cfg, POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY, + &bvd_api); diff --git a/app/drivers/zephyr/dts/bindings/zmk,battery-voltage-divider.yaml b/app/drivers/zephyr/dts/bindings/zmk,battery-voltage-divider.yaml index f6e06427..3f391d78 100644 --- a/app/drivers/zephyr/dts/bindings/zmk,battery-voltage-divider.yaml +++ b/app/drivers/zephyr/dts/bindings/zmk,battery-voltage-divider.yaml @@ -6,4 +6,9 @@ description: Battery SoC monitoring using voltage divider compatible: "zmk,battery-voltage-divider" include: voltage-divider.yaml + +properties: + label: + required: true + type: string \ No newline at end of file