drivers: comparator: implement the silabs_acmp compatible driver

This implements the comparator driver for silabs acmp peripherals using the silabs,acmp compatible binding. Signed-off-by: Christian Galante <[email protected]>
zephyrproject-rtos · Jan 17, 2025 · 5925121 · 5925121
1 parent 7fd0c05
commit 5925121
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diff --git a/drivers/comparator/CMakeLists.txt b/drivers/comparator/CMakeLists.txt
@@ -6,6 +6,7 @@ zephyr_syscall_header(${ZEPHYR_BASE}/include/zephyr/drivers/comparator.h)
 zephyr_library()
 
 zephyr_library_sources_ifdef(CONFIG_USERSPACE comparator_handlers.c)
+zephyr_library_sources_ifdef(CONFIG_COMPARATOR_SILABS_ACMP comparator_silabs_acmp.c)
 zephyr_library_sources_ifdef(CONFIG_COMPARATOR_FAKE_COMP comparator_fake_comp.c)
 zephyr_library_sources_ifdef(CONFIG_COMPARATOR_MCUX_ACMP comparator_mcux_acmp.c)
 zephyr_library_sources_ifdef(CONFIG_COMPARATOR_NRF_COMP comparator_nrf_comp.c)

diff --git a/drivers/comparator/Kconfig b/drivers/comparator/Kconfig
@@ -19,6 +19,7 @@ config COMPARATOR_INIT_PRIORITY
 	  Comparator device driver initialization priority.
 
 rsource "Kconfig.fake_comp"
+rsource "Kconfig.silabs_acmp"
 rsource "Kconfig.mcux_acmp"
 rsource "Kconfig.nrf_comp"
 rsource "Kconfig.nrf_lpcomp"

diff --git a/drivers/comparator/Kconfig.silabs_acmp b/drivers/comparator/Kconfig.silabs_acmp
@@ -0,0 +1,9 @@
+config COMPARATOR_SILABS_ACMP
+	bool "Silabs ACMP comparator driver"
+	default y
+	depends on DT_HAS_SILABS_ACMP_ENABLED
+	select SOC_SILABS_ACMP
+	help
+	  Enable the comparator driver for the Analog Comparator hardware block
+	  present on Silicon Labs devices. This block is commonly used to
+	  monitor the power supply.
diff --git a/drivers/comparator/comparator_silabs_acmp.c b/drivers/comparator/comparator_silabs_acmp.c
@@ -0,0 +1,184 @@
+/*
+ * Copyright (c) 2024 Silicon Labs
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <em_device.h>
+#include <em_cmu.h>
+#include <em_acmp.h>
+#include <zephyr/device.h>
+#include <zephyr/drivers/comparator.h>
+#include <zephyr/drivers/clock_control.h>
+#include <zephyr/drivers/clock_control/clock_control_silabs.h>
+#include <zephyr/irq.h>
+
+#include <zephyr/logging/log.h>
+LOG_MODULE_REGISTER(silabs_acmp, CONFIG_COMPARATOR_LOG_LEVEL);
+
+#define DT_DRV_COMPAT silabs_acmp
+
+struct acmp_config {
+	ACMP_TypeDef *base;
+	const struct device *clock_dev;
+	const struct silabs_clock_control_cmu_config clock_cfg;
+	void (*irq_init)(void);
+	ACMP_Init_TypeDef init;
+	int input_negative;
+	int input_positive;
+};
+
+struct acmp_data {
+	uint32_t interrupt_mask;
+	comparator_callback_t callback;
+	void *user_data;
+};
+
+static int acmp_init(const struct device *dev)
+{
+	int err;
+	const struct acmp_config *config = dev->config;
+
+	/* Enable ACMP Clock */
+	err = clock_control_on(config->clock_dev, (clock_control_subsys_t)&config->clock_cfg);
+	if (err < 0) {
+		return err;
+	}
+
+	/* Initialize the ACMP */
+	ACMP_Init(config->base, &config->init);
+
+	/* Configure the ACMP Input Channels */
+	ACMP_ChannelSet(config->base, config->input_negative, config->input_positive);
+
+	/* Initialize the irq handler */
+	config->irq_init();
+
+	return 0;
+}
+
+static int acmp_get_output(const struct device *dev)
+{
+	const struct acmp_config *config = dev->config;
+
+	return config->base->STATUS & ACMP_STATUS_ACMPOUT;
+}
+
+static int acmp_set_trigger(const struct device *dev, enum comparator_trigger trigger)
+{
+	const struct acmp_config *config = dev->config;
+	struct acmp_data *data = dev->data;
+
+	/* Disable ACMP trigger interrupts */
+	ACMP_IntDisable(config->base, ACMP_IEN_RISE | ACMP_IEN_FALL);
+
+	switch (trigger) {
+	case COMPARATOR_TRIGGER_BOTH_EDGES:
+		ACMP_IntEnable(config->base, ACMP_IEN_RISE | ACMP_IEN_FALL);
+		data->interrupt_mask = ACMP_IEN_RISE | ACMP_IEN_FALL;
+		break;
+	case COMPARATOR_TRIGGER_RISING_EDGE:
+		ACMP_IntEnable(config->base, ACMP_IEN_RISE);
+		data->interrupt_mask = ACMP_IEN_RISE;
+		break;
+	case COMPARATOR_TRIGGER_FALLING_EDGE:
+		ACMP_IntEnable(config->base, ACMP_IEN_FALL);
+		data->interrupt_mask = ACMP_IEN_FALL;
+		break;
+	case COMPARATOR_TRIGGER_NONE:
+		data->interrupt_mask = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int acmp_set_trigger_callback(const struct device *dev, comparator_callback_t callback,
+				     void *user_data)
+{
+	const struct acmp_config *config = dev->config;
+	struct acmp_data *data = dev->data;
+
+	/* Disable ACMP trigger interrupts while setting callback */
+	ACMP_IntDisable(config->base, ACMP_IEN_RISE | ACMP_IEN_FALL);
+
+	data->callback = callback;
+	data->user_data = user_data;
+
+	if (data->callback == NULL) {
+		return 0;
+	}
+
+	/* Re-enable currently set ACMP trigger interrupts */
+	if (data->interrupt_mask) {
+		ACMP_IntEnable(config->base, data->interrupt_mask);
+	}
+
+	return 0;
+}
+
+static int acmp_trigger_is_pending(const struct device *dev)
+{
+	const struct acmp_config *config = dev->config;
+
+	if (ACMP_IntGetEnabled(config->base)) {
+		return 1;
+	}
+
+	return 0;
+}
+
+static void acmp_irq_handler(const struct device *dev)
+{
+	const struct acmp_config *config = dev->config;
+	struct acmp_data *data = dev->data;
+
+	ACMP_IntClear(config->base, ACMP_IF_RISE | ACMP_IF_FALL);
+
+	if (data->callback == NULL) {
+		return;
+	}
+
+	data->callback(dev, data->user_data);
+}
+
+static DEVICE_API(comparator, acmp_api) = {
+	.get_output = acmp_get_output,
+	.set_trigger = acmp_set_trigger,
+	.set_trigger_callback = acmp_set_trigger_callback,
+	.trigger_is_pending = acmp_trigger_is_pending,
+};
+
+#define ACMP_DEVICE(inst)                                                                          \
+	static void acmp_irq_init##inst(void)                                                      \
+	{                                                                                          \
+		IRQ_CONNECT(DT_INST_IRQN(inst), DT_INST_IRQ(inst, priority), acmp_irq_handler,     \
+			    DEVICE_DT_INST_GET(inst), 0);                                          \
+                                                                                                   \
+		irq_enable(DT_INST_IRQN(inst));                                                    \
+	}                                                                                          \
+                                                                                                   \
+	static struct acmp_data acmp_data##inst;                                                   \
+                                                                                                   \
+	static const struct acmp_config acmp_config##inst = {                                      \
+		.base = (ACMP_TypeDef *)DT_INST_REG_ADDR(inst),                                    \
+		.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(inst)),                             \
+		.clock_cfg = SILABS_DT_INST_CLOCK_CFG(inst),                                       \
+		.irq_init = acmp_irq_init##inst,                                                   \
+		.init.biasProg = DT_INST_PROP(inst, bias),                                         \
+		.init.inputRange = DT_INST_ENUM_IDX(inst, input_range),                            \
+		.init.accuracy = DT_INST_ENUM_IDX(inst, accuracy_mode),                            \
+		.init.hysteresisLevel = DT_INST_ENUM_IDX(inst, hysteresis_mode),                   \
+		.init.inactiveValue = false,                                                       \
+		.init.vrefDiv = DT_INST_PROP(inst, vref_divider),                                  \
+		.init.enable = true,                                                               \
+		.input_negative = DT_INST_PROP(inst, input_negative),                              \
+		.input_positive = DT_INST_PROP(inst, input_positive),                              \
+	};                                                                                         \
+                                                                                                   \
+	DEVICE_DT_INST_DEFINE(inst, acmp_init, NULL, &acmp_data##inst, &acmp_config##inst,         \
+			      POST_KERNEL, CONFIG_COMPARATOR_INIT_PRIORITY, &acmp_api);
+
+DT_INST_FOREACH_STATUS_OKAY(ACMP_DEVICE)