Added code to deal with trackball with external power toggle

Basic code mimics changes suggested by ddudek mentioned in zmkfirmware#674
Added extra code to deal with interrupt triggers

app/drivers/sensor/pim447/pim447.c

@@ -17,6 +17,8 @@
 
 LOG_MODULE_REGISTER(PIM447, CONFIG_SENSOR_LOG_LEVEL);
 
+static int ext_power_status = true;
+
 static int pim447_sample_fetch(const struct device *dev, enum sensor_channel chan)
 {
 	struct pim447_data *data = dev->data;
@@ -86,11 +88,16 @@ static int pim447_led_set(const struct device *dev,
 	return 0;
 }
 
+static int pim447_update_ext_power(const struct device *dev, bool ext_power_status_new_value);
+
 int pim447_attr_set(const struct device *dev,
 		    enum sensor_channel chan,
 		    enum sensor_attribute attr,
 		    const struct sensor_value *val)
 {
+	if (attr == SENSOR_ATTR_CONFIGURATION) {
+		return pim447_update_ext_power(dev, (val->val1 == 1));
+	}
 	const struct device *i2c = pim447_i2c_device(dev);
 	uint8_t address = pim447_i2c_address(dev);
 	enum pim447_sensor_attribute pim447_attr = (enum pim447_sensor_attribute)attr;
@@ -195,6 +202,53 @@ static int pim447_init(const struct device *dev)
 	return 0;
 }
 
+static int pim447_update_ext_power(const struct device *dev, bool ext_power_status_new_value) {
+
+	// minimum sleep needed when waking up
+	if (ext_power_status_new_value == true) {
+		k_sleep(K_MSEC(30));
+	}
+#ifdef CONFIG_PIM447_TRIGGER
+	if (ext_power_status && !ext_power_status_new_value) {
+		pim447_suspend_interrupt(dev);
+		k_sleep(K_MSEC(30));
+	}
+#endif
+	// first update to I2C
+	if (dev->data != NULL) {
+		struct pim447_data *data = dev->data;
+		if (data->bus != NULL) {
+			if(i2c_update_ext_power(data->bus, ext_power_status_new_value)) {
+				LOG_ERR("Failed i2c_update_ext_power!");
+				return -EIO;
+			}
+		} else {
+			LOG_ERR("I2C bus is NULL");
+		}
+	} else {
+		LOG_ERR("trackball data is NULL");
+	}
+
+	if (ext_power_status != ext_power_status_new_value) {
+		if (ext_power_status_new_value == true)
+		{
+			// sleep after I2C reset
+			k_sleep(K_MSEC(30));
+
+			// re-init trackball, sends commands through i2c bus
+			pim447_init(dev);
+#ifdef CONFIG_PIM447_TRIGGER
+			pim447_resume_interrupt(dev);
+#endif
+		} else {
+			// no-op for now
+		}
+
+		ext_power_status = ext_power_status_new_value;
+	}
+	return 0;
+}
+
 #ifdef CONFIG_PIM447_TRIGGER
 #define PIM447_INST(n)\
     struct pim447_data pim447_data_##n;\

app/drivers/sensor/pim447/pim447.h

@@ -98,4 +98,6 @@ int pim447_trigger_set(const struct device *dev,
 		       sensor_trigger_handler_t handler);
 
 int pim447_init_interrupt(const struct device *dev);
+void pim447_suspend_interrupt(const struct device *dev);
+void pim447_resume_interrupt(const struct device *dev);
 #endif

app/drivers/sensor/pim447/pim447_trigger.c

@@ -122,13 +122,13 @@ static void pim447_thread_cb(const struct device *dev)
 static void pim447_thread(int dev_ptr, int unused)
 {
 	struct device *dev = INT_TO_POINTER(dev_ptr);
-	struct pim447_data *data = dev->driver_data;
+	struct pim447_data *data = (struct pim447_data *)dev->data;
 
 	ARG_UNUSED(unused);
 
 	while (1) {
 		k_sem_take(&data->gpio_sem, K_FOREVER);
-		pim447_thread_cb(dev);
+		pim447_thread_cb(data->dev);
 	}
 }
 #endif
@@ -201,4 +201,31 @@ int pim447_init_interrupt(const struct device *dev)
 #endif
 
 	return 0;
+}
+
+void pim447_suspend_interrupt(const struct device *dev) {
+	setup_alert(dev, false);
+	/* If ALERT is active we probably won't get the rising edge,
+	 * so invoke the callback manually.
+	 */
+	struct pim447_data *data = (struct pim447_data *)dev->data;
+	const struct pim447_config *cfg =
+		(const struct pim447_config *)dev->config;
+	if (gpio_pin_get(data->alert_gpio, cfg->alert_pin)) {
+		LOG_DBG("Already got new alert, invoking callback manually.");
+		handle_alert(dev);
+	}
+}
+void pim447_resume_interrupt(const struct device *dev) {
+	setup_alert(dev, true);
+	/* If ALERT is active we probably won't get the rising edge,
+	 * so invoke the callback manually.
+	 */
+	struct pim447_data *data = (struct pim447_data *)dev->data;
+	const struct pim447_config *cfg =
+		(const struct pim447_config *)dev->config;
+	if (gpio_pin_get(data->alert_gpio, cfg->alert_pin)) {
+		LOG_DBG("Already got new alert, invoking callback manually.");
+		handle_alert(dev);
+	}
 }

app/src/ext_power_generic.c

@@ -14,6 +14,7 @@
 #include <settings/settings.h>
 #include <drivers/gpio.h>
 #include <drivers/ext_power.h>
+#include <drivers/sensor.h>
 
 #if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
 
@@ -57,6 +58,19 @@ int ext_power_save_state() {
 #endif
 }
 
+static bool drivers_update_power_state(bool power) {
+    LOG_DBG("drivers_update_power_state: %s", power?"true":"false");
+    static const struct device *trackball;
+    trackball = device_get_binding("TRACKBALL");
+
+    if (trackball != NULL) {
+        struct sensor_value val;
+        val.val1 = power? 1 : 0;
+        sensor_attr_set(trackball, 0, SENSOR_ATTR_CONFIGURATION, &val);
+    }
+    return (trackball != NULL);
+}
+
 static int ext_power_generic_enable(const struct device *dev) {
     struct ext_power_generic_data *data = dev->data;
     const struct ext_power_generic_config *config = dev->config;
@@ -66,7 +80,12 @@ static int ext_power_generic_enable(const struct device *dev) {
         return -EIO;
     }
     data->status = true;
+    drivers_update_power_state(true);
+#if IS_ENABLED(CONFIG_PIM447_DEFAULT_EXT_POWER_OFF)
+    return 0;
+#else
     return ext_power_save_state();
+#endif
 }
 
 static int ext_power_generic_disable(const struct device *dev) {
@@ -78,7 +97,12 @@ static int ext_power_generic_disable(const struct device *dev) {
         return -EIO;
     }
     data->status = false;
+    drivers_update_power_state(false);
+#if IS_ENABLED(CONFIG_PIM447_DEFAULT_EXT_POWER_OFF)
+    return 0;
+#else
     return ext_power_save_state();
+#endif
 }
 
 static int ext_power_generic_get(const struct device *dev) {
@@ -141,7 +165,7 @@ static int ext_power_generic_init(const struct device *dev) {
         return -EIO;
     }
 
-#if IS_ENABLED(CONFIG_SETTINGS)
+#if IS_ENABLED(CONFIG_SETTINGS) && !IS_ENABLED(CONFIG_PIM447_DEFAULT_EXT_POWER_OFF)
     settings_subsys_init();
 
     int err = settings_register(&ext_power_conf);