drivers: regulator: fixed: simplify implementation

Remove regulator-fixed-sync specialization, create a single driver that
is always synchronous. The asynchronous part is rarely/never used, so
let's keep things simple for now.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

boards/arm/96b_wistrio/96b_wistrio.dts

@@ -48,7 +48,7 @@
 
 	/* regulator controlling SX oscillator enable */
 	sx-osc-enable {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "sx-osc-enable";
 		enable-gpios = <&gpioh 1 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/arduino_nano_33_ble/arduino_nano_33_ble_sense.dts

@@ -14,7 +14,7 @@
 	compatible = "arduino,arduino_nano_33_ble_sense";
 
 	mic_pwr: mic_pwr {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "mic_pwr";
 		enable-gpios = <&gpio0 17 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/arduino_portenta_h7/arduino_portenta_h7_m7.dts

@@ -23,7 +23,7 @@
 	};
 
 	oscen: oscen {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "oscen";
 		enable-gpios = <&gpioh 1 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/circuitdojo_feather_nrf9160/circuitdojo_feather_nrf9160_common.dts

@@ -82,7 +82,7 @@
 	};
 
 	nrf-ps-en {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "nrf_ps_en";
 		enable-gpios = <&gpio0 31 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/degu_evk/degu_evk.dts

@@ -58,14 +58,14 @@
 	};
 
 	en-3v3-switch {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_3v3_switch";
 		enable-gpios = <&gpio0 26 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;
 	};
 
 	en-vin1-moni {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_vin1_moni";
 		enable-gpios = <&gpio1 6 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/hexiwear_k64/hexiwear_k64.dts

@@ -62,21 +62,21 @@
 	};
 
 	en_bat_sens: enable-battery-sense {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_bat_sens";
 		enable-gpios = <&gpioc 14 GPIO_ACTIVE_LOW>;
 		regulator-boot-on;
 	};
 
 	en_ldo: enable-ldo {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_ldo";
 		enable-gpios = <&gpioa 29 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;
 	};
 
 	en_3v3b: enable-3v3b {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_3v3b";
 		enable-gpios = <&gpiob 12 GPIO_ACTIVE_LOW>;
 		regulator-boot-on;

boards/arm/lora_e5_dev_board/lora_e5_dev_board.dts

@@ -56,7 +56,7 @@
 		 * and for external devices(Grove, header).
 		 * Requires closed J15 (D9)
 		 */
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "pwr-3v3-ctrl";
 		enable-gpios = <&gpioa 9 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;
@@ -68,7 +68,7 @@
 		 * Available for external devices on header J2
 		 * Requires closed J6 (D10)
 		 */
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "pwr-5v-ctrl";
 		enable-gpios = <&gpiob 10 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/mimxrt1170_evk/mimxrt1170_evk_cm7.dts

@@ -39,7 +39,7 @@
 	};
 
 	en_mipi_display: enable-mipi-display {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_mipi_display";
 		enable-gpios = <&gpio11 16 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/nrf9160_innblue21/nrf9160_innblue21_common.dts

@@ -46,7 +46,7 @@
 	};
 
 	en_3v3_sensor: enable-3v3-sensor {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_3v3_sensor";
 		enable-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
 		startup-delay-us = <10000>;
@@ -54,7 +54,7 @@
 	};
 
 	en_5v0_boost: enable-5v0-boost {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_5v0_boost";
 		enable-gpios = <&gpio0 21 GPIO_ACTIVE_HIGH>;
 		startup-delay-us = <10000>;

boards/arm/nrf9160_innblue22/nrf9160_innblue22_common.dts

@@ -46,7 +46,7 @@
 	};
 
 	en_5v0_boost: enable-5v0-boost {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "en_5v0_boost";
 		enable-gpios = <&gpio0 21 GPIO_ACTIVE_HIGH>;
 		startup-delay-us = <10000>;

boards/arm/swan_r5/swan_r5.dts

@@ -42,7 +42,7 @@
 	};
 
 	supply-3v3 {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "supply-3v3";
 		enable-gpios = <&gpioe 4 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/arm/thingy52_nrf52832/thingy52_nrf52832.dts

@@ -80,7 +80,7 @@
 	};
 
 	spk_pwr: spk-pwr-ctrl {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "spk-pwr-ctrl";
 		enable-gpios = <&gpio0 29 GPIO_ACTIVE_HIGH>;
 	};

boards/arm/thingy53_nrf5340/thingy53_nrf5340_common.dts

@@ -64,7 +64,7 @@
 	};
 
 	npm1100_force_pwm_mode: npm1100_force_pwm_mode {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "npm1100_force_pwm_mode";
 		enable-gpios = <&gpio0 8 GPIO_ACTIVE_HIGH>;
 		status = "disabled";
@@ -80,14 +80,14 @@
 	};
 
 	regulator_3v3: regulator-3v3-ctrl {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "ncp114";
 		enable-gpios = <&gpio0 15 GPIO_ACTIVE_LOW>;
 		regulator-boot-on;
 	};
 
 	sensor_pwr_ctrl: sensor-pwr-ctrl {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "tck106ag";
 		enable-gpios = <&gpio0 31 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

boards/xtensa/odroid_go/odroid_go.dts

@@ -57,7 +57,7 @@
 	};
 
 	lcd_backlight_en {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "lcd_backlight_enable";
 		enable-gpios = <&gpio0 14 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

doc/hardware/peripherals/regulators.rst

@@ -14,14 +14,6 @@ inherently asynchronous.  To maximize flexibility the
 the regulator subsystem.  Nodes with a devicetree compatible of
 ``regulator-fixed`` are the most common flexible regulators.
 
-In some cases the transitions are close enough to instantaneous that the
-the asynchronous driver implementation is not needed, and the resource
-cost in RAM is not justified.  Such a regulator still uses the
-asynchronous API, but may be implemented internally in a way that
-ensures the result of the operation is presented before the transition
-completes.  Zephyr recognizes devicetree nodes with a compatible of
-``regulator-fixed-sync`` as devices with synchronous transitions.
-
 The ``vin-supply`` devicetree property is used to identify the
 regulator(s) that a devicetree node directly depends on.  Within the
 driver for the node the regulator API is used to issue requests for

drivers/regulator/regulator_fixed.c

@@ -1,15 +1,18 @@
 /*
  * Copyright 2019-2020 Peter Bigot Consulting, LLC
+ * Copyright 2022 Nordic Semiconductor ASA
  * SPDX-License-Identifier: Apache-2.0
  */
 
 #define DT_DRV_COMPAT regulator_fixed
 
+#include <stdint.h>
+
 #include <zephyr/kernel.h>
 #include <zephyr/drivers/regulator.h>
 #include <zephyr/drivers/gpio.h>
-
 #include <zephyr/logging/log.h>
+
 LOG_MODULE_REGISTER(regulator_fixed, CONFIG_REGULATOR_LOG_LEVEL);
 
 #define OPTION_ALWAYS_ON_POS 0
@@ -17,366 +20,118 @@ LOG_MODULE_REGISTER(regulator_fixed, CONFIG_REGULATOR_LOG_LEVEL);
 #define OPTION_BOOT_ON_POS 1
 #define OPTION_BOOT_ON BIT(OPTION_BOOT_ON_POS)
 
-struct driver_config {
+struct regulator_fixed_config {
-	const char *regulator_name;
 	uint32_t startup_delay_us;
 	uint32_t off_on_delay_us;
 	struct gpio_dt_spec enable;
 	uint8_t options;
 };
 
-enum work_task {
+struct regulator_fixed_data {
-	WORK_TASK_UNDEFINED,
+	struct onoff_sync_service srv;
-	WORK_TASK_ENABLE,
-	WORK_TASK_DISABLE,
-	WORK_TASK_DELAY,
 };
 
-struct driver_data_onoff {
+static int regulator_fixed_enable(const struct device *dev,
-	const struct device *dev;
+				  struct onoff_client *cli)
-	struct onoff_manager mgr;
-#ifdef CONFIG_MULTITHREADING
-	struct k_work_delayable dwork;
-#endif /* CONFIG_MULTITHREADING */
-	onoff_notify_fn notify;
-	enum work_task task;
-};
-
-/* Common initialization of GPIO device and pin state.
- *
- * @param dev the regulator device, whether sync or onoff
- *
- * @param gpiop where to store the GPIO device pointer
- *
- * @return negative on error, otherwise zero.
- */
-static int common_init(const struct device *dev)
 {
-	const struct driver_config *cfg = dev->config;
+	const struct regulator_fixed_config *cfg = dev->config;
-	gpio_flags_t flags;
+	struct regulator_fixed_data *data = dev->data;
+	k_spinlock_key_t key;
+	int ret;
+
+	if ((cfg->options & OPTION_ALWAYS_ON) != 0) {
+		return 0;
+	}
+
+	ret = onoff_sync_lock(&data->srv, &key);
+	if (ret > 0) {
+		goto finalize;
+	}
+
+	ret = gpio_pin_set_dt(&cfg->enable, 1);
+	if (ret < 0) {
+		goto finalize;
+	}
+
+	if (cfg->off_on_delay_us > 0U) {
+		k_sleep(K_USEC(cfg->off_on_delay_us));
+	}
+
+finalize:
+	return onoff_sync_finalize(&data->srv, key, cli, ret, true);
+}
+
+static int regulator_fixed_disable(const struct device *dev)
+{
+	const struct regulator_fixed_config *cfg = dev->config;
+	struct regulator_fixed_data *data = dev->data;
+	k_spinlock_key_t key;
+	int ret;
+
+	if  ((cfg->options & OPTION_ALWAYS_ON) != 0) {
+		return 0;
+	}
+
+	ret = onoff_sync_lock(&data->srv, &key);
+	if (ret != 1) {
+		goto finalize;
+	}
+
+	ret = gpio_pin_set_dt(&cfg->enable, 0);
+	if (ret < 0) {
+		return ret;
+	}
+
+finalize:
+	return onoff_sync_finalize(&data->srv, key, NULL, ret, false);
+}
+
+static const struct regulator_driver_api regulator_fixed_api = {
+	.enable = regulator_fixed_enable,
+	.disable = regulator_fixed_disable,
+};
+
+static int regulator_fixed_init(const struct device *dev)
+{
+	const struct regulator_fixed_config *cfg = dev->config;
+	int ret;
 
 	if (!device_is_ready(cfg->enable.port)) {
 		LOG_ERR("GPIO port: %s not ready", cfg->enable.port->name);
 		return -ENODEV;
 	}
 
-	bool on = cfg->options & (OPTION_ALWAYS_ON | OPTION_BOOT_ON);
+	if ((cfg->options & (OPTION_ALWAYS_ON | OPTION_BOOT_ON)) != 0U) {
-	uint32_t delay_us = 0;
+		ret = gpio_pin_configure_dt(&cfg->enable, GPIO_OUTPUT_ACTIVE);
+		if (ret < 0) {
+			return ret;
+		}
 
-	if (on) {
+		k_busy_wait(cfg->startup_delay_us);
-		flags = GPIO_OUTPUT_ACTIVE;
-		delay_us = cfg->startup_delay_us;
 	} else {
-		flags = GPIO_OUTPUT_INACTIVE;
+		ret = gpio_pin_configure_dt(&cfg->enable, GPIO_OUTPUT_INACTIVE);
-	}
+		if (ret < 0) {
-
+			return ret;
-	int rc = gpio_pin_configure_dt(&cfg->enable, flags);
-
-	if ((rc == 0) && (delay_us > 0)) {
-		/* Turned on and we have to wait until the on
-		 * completes.  Since this is in the driver init we
-		 * can't sleep.
-		 */
-		k_busy_wait(delay_us);
-	}
-
-	return rc;
-}
-
-static void finalize_transition(struct driver_data_onoff *data,
-				onoff_notify_fn notify,
-				uint32_t delay_us,
-				int rc)
-{
-	const struct driver_config *cfg = data->dev->config;
-
-	LOG_DBG("%s: finalize %d delay %u us", cfg->regulator_name, rc, delay_us);
-
-	/* If there's no error and we have to delay, do so. */
-	if ((rc >= 0) && (delay_us > 0)) {
-		/* If the delay is less than a tick or we're not
-		 * sleep-capable we have to busy-wait.
-		 */
-		if ((k_us_to_ticks_floor32(delay_us) == 0)
-		    || k_is_pre_kernel()
-		    || !IS_ENABLED(CONFIG_MULTITHREADING)) {
-			k_busy_wait(delay_us);
-#ifdef CONFIG_MULTITHREADING
-		} else {
-			/* Otherwise sleep in the work queue. */
-			__ASSERT_NO_MSG(data->task == WORK_TASK_UNDEFINED);
-			data->task = WORK_TASK_DELAY;
-			data->notify = notify;
-			rc = k_work_schedule(&data->dwork, K_USEC(delay_us));
-			if (rc >= 0) {
-				return;
-			}
-#endif /* CONFIG_MULTITHREADING */
 		}
 	}
 
-	notify(&data->mgr, rc);
+	return 0;
 }
 
-#ifdef CONFIG_MULTITHREADING
+#define REGULATOR_FIXED_DEFINE(inst)                                           \
-/* The worker is used for several things:
+	static const struct regulator_fixed_config config##inst = {            \
- *
+		.startup_delay_us = DT_INST_PROP(inst, startup_delay_us),      \
- * * If a transition occurred in a context where the GPIO state could
+		.off_on_delay_us = DT_INST_PROP(inst, off_on_delay_us),        \
- *   not be changed that's done here.
+		.enable = GPIO_DT_SPEC_INST_GET(inst, enable_gpios),           \
- * * If a start or stop transition requires a delay that exceeds one
+		.options = (DT_INST_PROP(inst, regulator_boot_on)              \
- *   tick the notification after the delay is performed here.
+			    << OPTION_BOOT_ON_POS) |                           \
- */
+			   (DT_INST_PROP(inst, regulator_always_on)            \
-static void onoff_worker(struct k_work *work)
+			    << OPTION_ALWAYS_ON_POS),                          \
-{
+	};                                                                     \
-	struct k_work_delayable *dwork
+                                                                               \
-		= k_work_delayable_from_work(work);
+	DEVICE_DT_INST_DEFINE(inst, regulator_fixed_init, NULL, NULL,          \
-	struct driver_data_onoff *data
+			      &config##inst, POST_KERNEL,                      \
-		= CONTAINER_OF(dwork, struct driver_data_onoff,
+			      CONFIG_REGULATOR_FIXED_INIT_PRIORITY,            \
-			       dwork);
+			      &regulator_fixed_api);
-	onoff_notify_fn notify = data->notify;
-	const struct driver_config *cfg = data->dev->config;
-	uint32_t delay_us = 0;
-	int rc = 0;
 
-	if (data->task == WORK_TASK_ENABLE) {
+DT_INST_FOREACH_STATUS_OKAY(REGULATOR_FIXED_DEFINE)
-		rc = gpio_pin_set_dt(&cfg->enable, true);
-		LOG_DBG("%s: work enable: %d", cfg->regulator_name, rc);
-		delay_us = cfg->startup_delay_us;
-	} else if (data->task == WORK_TASK_DISABLE) {
-		rc = gpio_pin_set_dt(&cfg->enable, false);
-		LOG_DBG("%s: work disable: %d", cfg->regulator_name, rc);
-		delay_us = cfg->off_on_delay_us;
-	} else if (data->task == WORK_TASK_DELAY) {
-		LOG_DBG("%s: work delay complete", cfg->regulator_name);
-	}
-
-	data->notify = NULL;
-	data->task = WORK_TASK_UNDEFINED;
-	finalize_transition(data, notify, delay_us, rc);
-}
-#endif /* CONFIG_MULTITHREADING */
-
-static void start(struct onoff_manager *mgr,
-		  onoff_notify_fn notify)
-{
-	struct driver_data_onoff *data =
-		CONTAINER_OF(mgr, struct driver_data_onoff, mgr);
-	const struct driver_config *cfg = data->dev->config;
-	uint32_t delay_us = cfg->startup_delay_us;
-	int rc = 0;
-
-	LOG_DBG("%s: start", cfg->regulator_name);
-
-	if ((cfg->options & OPTION_ALWAYS_ON) != 0) {
-		delay_us = 0;
-		goto finalize;
-	}
-
-	rc = gpio_pin_set_dt(&cfg->enable, true);
-
-#ifdef CONFIG_MULTITHREADING
-	if (rc == -EWOULDBLOCK) {
-		/* Perform the enable and finalization in a work item.
-		 */
-		LOG_DBG("%s: start deferred", cfg->regulator_name);
-		__ASSERT_NO_MSG(data->task == WORK_TASK_UNDEFINED);
-		data->task = WORK_TASK_ENABLE;
-		data->notify = notify;
-		k_work_schedule(&data->dwork, K_NO_WAIT);
-		return;
-	}
-#endif /* CONFIG_MULTITHREADING */
-
-finalize:
-	finalize_transition(data, notify, delay_us, rc);
-
-	return;
-}
-
-static void stop(struct onoff_manager *mgr,
-		 onoff_notify_fn notify)
-{
-	struct driver_data_onoff *data =
-		CONTAINER_OF(mgr, struct driver_data_onoff, mgr);
-	const struct driver_config *cfg = data->dev->config;
-	uint32_t delay_us = cfg->off_on_delay_us;
-	int rc = 0;
-
-	LOG_DBG("%s: stop", cfg->regulator_name);
-
-	if ((cfg->options & OPTION_ALWAYS_ON) != 0) {
-		delay_us = 0;
-		goto finalize;
-	}
-
-	rc = gpio_pin_set_dt(&cfg->enable, false);
-
-#ifdef CONFIG_MULTITHREADING
-	if (rc == -EWOULDBLOCK) {
-		/* Perform the disable and finalization in a work
-		 * item.
-		 */
-		LOG_DBG("%s: stop deferred", cfg->regulator_name);
-		__ASSERT_NO_MSG(data->task == WORK_TASK_UNDEFINED);
-		data->task = WORK_TASK_DISABLE;
-		data->notify = notify;
-		k_work_schedule(&data->dwork, K_NO_WAIT);
-		return;
-	}
-#endif /* CONFIG_MULTITHREADING */
-
-finalize:
-	finalize_transition(data, notify, delay_us, rc);
-
-	return;
-}
-
-static int enable_onoff(const struct device *dev, struct onoff_client *cli)
-{
-	struct driver_data_onoff *data = dev->data;
-
-	return onoff_request(&data->mgr, cli);
-}
-
-static int disable_onoff(const struct device *dev)
-{
-	struct driver_data_onoff *data = dev->data;
-
-	return onoff_release(&data->mgr);
-}
-
-static const struct onoff_transitions transitions =
-	ONOFF_TRANSITIONS_INITIALIZER(start, stop, NULL);
-
-static const struct regulator_driver_api api_onoff = {
-	.enable = enable_onoff,
-	.disable = disable_onoff,
-};
-
-static int regulator_fixed_init_onoff(const struct device *dev)
-{
-	struct driver_data_onoff *data = dev->data;
-	int rc;
-
-	data->dev = dev;
-	rc = onoff_manager_init(&data->mgr, &transitions);
-	__ASSERT_NO_MSG(rc == 0);
-
-#ifdef CONFIG_MULTITHREADING
-	k_work_init_delayable(&data->dwork, onoff_worker);
-#endif /* CONFIG_MULTITHREADING */
-
-	rc = common_init(dev);
-	if (rc >= 0) {
-		rc = 0;
-	}
-
-	LOG_INF("%s onoff: %d", dev->name, rc);
-
-	return rc;
-}
-
-struct driver_data_sync {
-	struct onoff_sync_service srv;
-};
-
-#if DT_HAS_COMPAT_STATUS_OKAY(regulator_fixed_sync) - 0
-
-static int enable_sync(const struct device *dev, struct onoff_client *cli)
-{
-	struct driver_data_sync *data = dev->data;
-	const struct driver_config *cfg = dev->config;
-	k_spinlock_key_t key;
-	int rc = onoff_sync_lock(&data->srv, &key);
-
-	if ((rc == 0)
-	    && ((cfg->options & OPTION_ALWAYS_ON) == 0)) {
-		rc = gpio_pin_set_dt(&cfg->enable, true);
-	}
-
-	return onoff_sync_finalize(&data->srv, key, cli, rc, true);
-}
-
-static int disable_sync(const struct device *dev)
-{
-	struct driver_data_sync *data = dev->data;
-	const struct driver_config *cfg = dev->config;
-	k_spinlock_key_t key;
-	int rc = onoff_sync_lock(&data->srv, &key);
-
-	if  ((cfg->options & OPTION_ALWAYS_ON) != 0) {
-		rc = 0;
-	} else if (rc == 1) {
-		rc = gpio_pin_set_dt(&cfg->enable, false);
-	} else if (rc == 0) {
-		rc = -EINVAL;
-	} /* else rc > 0, leave it on */
-
-	return onoff_sync_finalize(&data->srv, key, NULL, rc, false);
-}
-
-static const struct regulator_driver_api api_sync = {
-	.enable = enable_sync,
-	.disable = disable_sync,
-};
-
-static int regulator_fixed_init_sync(const struct device *dev)
-{
-	const struct driver_config *cfg = dev->config;
-	int rc = common_init(dev);
-
-	(void)regulator_fixed_init_onoff;
-	(void)api_onoff;
-	(void)cfg;
-
-	__ASSERT(cfg->startup_delay_us == 0,
-		 "sync not valid with startup delay");
-	__ASSERT(cfg->off_on_delay_us == 0,
-		 "sync not valid with shutdown delay");
-
-	LOG_INF("%s sync: %d", dev->name, rc);
-
-	return rc;
-}
-
-#endif /* DT_HAS_COMPAT_STATUS_OK(regulator_fixed_sync) */
-
-/* This should also check:
- *  && DT_INST_PROP(id, startup_delay_us) == 0
- *  && DT_INST_PROP(id, off_on_delay_us) == 0
- * but the preprocessor magic doesn't seem able to do that so we'll assert
- * in init instead.
- */
-#define REG_IS_SYNC(id)						\
-	DT_NODE_HAS_COMPAT(DT_DRV_INST(id), regulator_fixed_sync)
-
-#define REG_DATA_TAG(id) COND_CODE_1(REG_IS_SYNC(id),	\
-		(driver_data_sync),			\
-		(driver_data_onoff))
-#define REG_API(id) COND_CODE_1(REG_IS_SYNC(id),	\
-		(api_sync),				\
-		(api_onoff))
-#define REG_INIT(id) COND_CODE_1(REG_IS_SYNC(id),	\
-		(regulator_fixed_init_sync),		\
-		(regulator_fixed_init_onoff))
-
-#define REGULATOR_DEVICE(id) \
-static const struct driver_config regulator_##id##_cfg = { \
-	.regulator_name = DT_INST_PROP(id, regulator_name), \
-	.startup_delay_us = DT_INST_PROP(id, startup_delay_us), \
-	.off_on_delay_us = DT_INST_PROP(id, off_on_delay_us), \
-	.enable = GPIO_DT_SPEC_INST_GET(id, enable_gpios), \
-	.options = (DT_INST_PROP(id, regulator_boot_on)	\
-		    << OPTION_BOOT_ON_POS) \
-		  | (DT_INST_PROP(id, regulator_always_on) \
-		     << OPTION_ALWAYS_ON_POS), \
-}; \
-\
-static struct REG_DATA_TAG(id) regulator_##id##_data; \
-\
-DEVICE_DT_INST_DEFINE(id, REG_INIT(id), NULL,			       \
-		 &regulator_##id##_data, &regulator_##id##_cfg,	       \
-		 POST_KERNEL, CONFIG_REGULATOR_FIXED_INIT_PRIORITY,    \
-		 &REG_API(id));
-
-DT_INST_FOREACH_STATUS_OKAY(REGULATOR_DEVICE)

dts/bindings/regulator/regulator-fixed.yaml

@@ -11,16 +11,6 @@ include:
       - regulator-boot-on
       - regulator-always-on
 
-# NOTE: The driver supports "regulator-fixed-sync" as a specializing
-# variant when it's known that the GPIO state change operations are
-# isr-ok and not sleep, and both startup and off-on delays are zero.
-# This bypasses the asynchronous onoff manager which optimizes both time
-# and memory use.
-#
-# To enable this use both:
-#    compatible = "regulator-fixed-sync", "regulator-fixed";
-#
-
 compatible: "regulator-fixed"
 
 properties:

samples/drivers/led_apa102/boards/blueclover_plt_demo_v2_nrf52832.overlay

@@ -6,7 +6,7 @@
 
 / {
 	led_pwr: led-pwr-ctrl {
-		compatible = "regulator-fixed-sync", "regulator-fixed";
+		compatible = "regulator-fixed";
 		regulator-name = "led-pwr-ctrl";
 		enable-gpios = <&gpio0 25 GPIO_ACTIVE_HIGH>;
 		regulator-boot-on;

tests/drivers/regulator/fixed/README.txt

@@ -7,12 +7,9 @@ pins be shorted so that changes made to the state of one can be verified
 by inspecting the other.
 
 Unlike the GPIO driver test the behavior of a fixed regulator depends
-heavily on the properties specified in its devicetree node.  The
+heavily on the properties specified in its devicetree node. The initial
-``compatible`` property causes the underlying driver implementation to
+state of the regulator, whether it can be changed, and enforced transition
-select between one that supports asynchronous transitions and an
+delays are all controlled by devicetree properties.
-optimized one synchronous transitions.  The initial state of the
-regulator, whether it can be changed, and enforced transition delays are
-all controlled by devicetree properties.
 
 Because the regulator can only be configured at system startup it is
 necessary to test varying configurations in separate test sessions.  The

tests/drivers/regulator/fixed/dts/test_common.dtsi

@@ -5,11 +5,7 @@
 
 / {
 	regulator {
-		compatible =
+		compatible = "regulator-fixed";
-#if APP_DTS_REGULATOR_SYNC
-			"regulator-fixed-sync",
-#endif
-			"regulator-fixed";
 		regulator-name = "test";
 #ifdef APP_DTS_REGULATOR_ALWAYS_ON
 		regulator-always-on;

tests/drivers/regulator/fixed/src/main.c

@@ -14,7 +14,6 @@
 BUILD_ASSERT(DT_NODE_HAS_COMPAT_STATUS(REGULATOR_NODE, regulator_fixed, okay));
 BUILD_ASSERT(DT_NODE_HAS_COMPAT_STATUS(CHECK_NODE, test_regulator_fixed, okay));
 
-#define IS_REGULATOR_SYNC DT_NODE_HAS_COMPAT_STATUS(REGULATOR_NODE, regulator_fixed_sync, okay)
 #define BOOT_ON DT_PROP(REGULATOR_NODE, regulator_boot_on)
 #define ALWAYS_ON DT_PROP(REGULATOR_NODE, regulator_always_on)
 #define STARTUP_DELAY_US DT_PROP(REGULATOR_NODE, startup_delay_us)

tests/drivers/regulator/fixed/testcase.yaml

@@ -9,19 +9,13 @@ common:
     - nrf52840dk_nrf52840
 
 tests:
-  drivers.regulator.fixed.onoff:
+  drivers.regulator.fixed:
     depends_on: gpio
-  drivers.regulator.fixed.onoff.on_delay:
+  drivers.regulator.fixed.on_delay:
     extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_ON_DELAYED"
-  drivers.regulator.fixed.onoff.off_delay:
+  drivers.regulator.fixed.off_delay:
     extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_OFF_DELAYED"
-  drivers.regulator.fixed.onoff.boot_on:
+  drivers.regulator.fixed.boot_on:
     extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_BOOT_ON"
-  drivers.regulator.fixed.onoff.always_on:
+  drivers.regulator.fixed.always_on:
     extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_ALWAYS_ON"
-  drivers.regulator.fixed.sync:
-    extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_SYNC"
-  drivers.regulator.fixed.sync.boot_on:
-    extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_SYNC;-DAPP_DTS_REGULATOR_BOOT_ON"
-  drivers.regulator.fixed.sync.always_on:
-    extra_args: "DTS_EXTRA_CPPFLAGS=-DAPP_DTS_REGULATOR_SYNC;-DAPP_DTS_REGULATOR_ALWAYS_ON"