From 3082455aecc98532807aba3226321a94d2ed4b0c Mon Sep 17 00:00:00 2001
From: Nick <nick.win999@gmail.com>
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