drivers: dac: add driver for the NXP Kinetis DAC32

Add driver shim for the NXP Kinetis Digital-to-Analog (DAC32) module.

Signed-off-by: Henrik Brix Andersen <henrik@brixandersen.dk>

drivers/dac/CMakeLists.txt

@@ -2,5 +2,6 @@
 
 zephyr_library()
 
+zephyr_library_sources_ifdef(CONFIG_DAC_MCUX_DAC32	dac_mcux_dac32.c)
 zephyr_library_sources_ifdef(CONFIG_DAC_STM32		dac_stm32.c)
 zephyr_library_sources_ifdef(CONFIG_USERSPACE		dac_handlers.c)

drivers/dac/Kconfig

@@ -17,6 +17,8 @@ module = DAC
 module-str = DAC
 source "subsys/logging/Kconfig.template.log_config"
 
+source "drivers/dac/Kconfig.mcux"
+
 source "drivers/dac/Kconfig.stm32"
 
 endif # DAC

drivers/dac/Kconfig.mcux

@@ -0,0 +1,11 @@
+# DAC configuration options
+
+# Copyright (c) 2020 Henrik Brix Andersen <henrik@brixandersen.dk>
+#
+# SPDX-License-Identifier: Apache-2.0
+
+config DAC_MCUX_DAC32
+	bool "NXP Kinetis MCUX DAC32 driver"
+	depends on HAS_MCUX_DAC32
+	help
+	  Enable the driver for the NXP Kinetis MCUX DAC32.

drivers/dac/dac_mcux_dac32.c

@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2020 Henrik Brix Andersen <henrik@brixandersen.dk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT nxp_kinetis_dac32
+
+#include <zephyr.h>
+#include <drivers/dac.h>
+#include <logging/log.h>
+
+#include <fsl_dac32.h>
+
+LOG_MODULE_REGISTER(dac_mcux_dac32, CONFIG_DAC_LOG_LEVEL);
+
+struct mcux_dac32_config {
+	DAC_Type *base;
+	dac32_reference_voltage_source_t reference;
+	bool buffered;
+	bool low_power;
+};
+
+struct mcux_dac32_data {
+	bool configured;
+};
+
+static int mcux_dac32_channel_setup(struct device *dev,
+				    const struct dac_channel_cfg *channel_cfg)
+{
+	const struct mcux_dac32_config *config = dev->config->config_info;
+	struct mcux_dac32_data *data = dev->driver_data;
+	dac32_config_t dac32_config;
+
+	if (channel_cfg->channel_id != 0) {
+		LOG_ERR("unsupported channel %d", channel_cfg->channel_id);
+		return -ENOTSUP;
+	}
+
+	if (channel_cfg->resolution != 12) {
+		LOG_ERR("unsupported resolution %d", channel_cfg->resolution);
+		return -ENOTSUP;
+	}
+
+	DAC32_GetDefaultConfig(&dac32_config);
+	dac32_config.enableLowPowerMode = config->low_power;
+	dac32_config.referenceVoltageSource = config->reference;
+
+	DAC32_Init(config->base, &dac32_config);
+	DAC32_EnableBufferOutput(config->base, config->buffered);
+
+	data->configured = true;
+
+	return 0;
+}
+
+static int mcux_dac32_write_value(struct device *dev, u8_t channel, u32_t value)
+{
+	const struct mcux_dac32_config *config = dev->config->config_info;
+	struct mcux_dac32_data *data = dev->driver_data;
+
+	if (!data->configured) {
+		LOG_ERR("channel not initialized");
+		return -EINVAL;
+	}
+
+	if (channel != 0) {
+		LOG_ERR("unsupported channel %d", channel);
+		return -ENOTSUP;
+	}
+
+	if (value >= 4096) {
+		LOG_ERR("value %d out of range", value);
+		return -EINVAL;
+	}
+
+	/* Static operation */
+	DAC32_EnableBuffer(config->base, false);
+
+	DAC32_SetBufferValue(config->base, 0, value);
+	DAC32_Enable(config->base, true);
+
+	return 0;
+}
+
+static int mcux_dac32_init(struct device *dev)
+{
+	return 0;
+}
+
+static const struct dac_driver_api mcux_dac32_driver_api = {
+	.channel_setup = mcux_dac32_channel_setup,
+	.write_value = mcux_dac32_write_value,
+};
+
+#define TO_DAC32_VREF_SRC(val) \
+	_DO_CONCAT(kDAC32_ReferenceVoltageSourceVref, val)
+
+#define MCUX_DAC32_INIT(n) \
+	static struct mcux_dac32_data mcux_dac32_data_##n;		\
+									\
+	static const struct mcux_dac32_config mcux_dac32_config_##n = {	\
+		.base = (DAC_Type *)DT_INST_REG_ADDR(n),		\
+		.reference =						\
+		TO_DAC32_VREF_SRC(DT_INST_PROP(n, voltage_reference)),	\
+		.buffered = DT_INST_PROP(n, buffered),			\
+		.low_power = DT_INST_PROP(n, low_power_mode),		\
+	};								\
+									\
+	DEVICE_AND_API_INIT(mcux_dac32_##n, DT_INST_LABEL(n),		\
+			mcux_dac32_init, &mcux_dac32_data_##n,		\
+			&mcux_dac32_config_##n,				\
+			POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,\
+			&mcux_dac32_driver_api)
+
+DT_INST_FOREACH(MCUX_DAC32_INIT)