adc: Introduce new mcux adc16 driver

Adds a shim layer around the mcux adc16 driver to adapt it to the Zephyr
adc interface.

Jira: ZEP-1396

Signed-off-by: Maureen Helm <maureen.helm@nxp.com>

arch/arm/soc/nxp_kinetis/Kconfig

@@ -64,6 +64,12 @@ config HAS_LPSCI
 	help
 	  Set if the low power uart (LPSCI) module is present in the SoC.
 
+config HAS_ADC16
+	bool
+	default n
+	help
+	  Set if the 16-bit ADC (ADC16) module is present in the SoC.
+
 config HAS_SYSMPU
 	bool "Enable MPU"
 	depends on CPU_HAS_MPU

drivers/adc/Kconfig

@@ -303,4 +303,12 @@ endif
 
 endif # ADC_QMSI || ADC_QMSI_SS
 
+config ADC_MCUX_ADC16
+	bool "MCUX ADC16 driver"
+	depends on HAS_MCUX && HAS_ADC16
+	select HAS_DTS_ADC
+	default n
+	help
+	  Enable the MCUX ADC16 driver.
+
 endif # ADC

drivers/adc/Makefile

@@ -1,4 +1,5 @@
 obj-$(CONFIG_ADC_DW) += adc_dw.o
+obj-$(CONFIG_ADC_MCUX_ADC16) += adc_mcux_adc16.o
 obj-$(CONFIG_ADC_TI_ADC108S102) += adc_ti_adc108s102.o
 obj-$(CONFIG_ADC_QMSI) += adc_qmsi.o
 obj-$(CONFIG_ADC_QMSI_SS) += adc_qmsi_ss.o

drivers/adc/adc_mcux_adc16.c

@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2017, NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <errno.h>
+#include <adc.h>
+#include <soc.h>
+#include <fsl_adc16.h>
+
+struct mcux_adc16_config {
+	ADC_Type *base;
+	void (*irq_config_func)(struct device *dev);
+};
+
+struct mcux_adc16_data {
+	struct k_sem sync;
+	u32_t channel_group;
+	u32_t result;
+};
+
+static void mcux_adc16_enable(struct device *dev)
+{
+	ARG_UNUSED(dev);
+}
+
+static void mcux_adc16_disable(struct device *dev)
+{
+	ARG_UNUSED(dev);
+}
+
+static int mcux_adc16_read(struct device *dev, struct adc_seq_table *seq_table)
+{
+	const struct mcux_adc16_config *config = dev->config->config_info;
+	struct mcux_adc16_data *data = dev->driver_data;
+	ADC_Type *base = config->base;
+
+	struct adc_seq_entry *entry = seq_table->entries;
+	adc16_channel_config_t channel_config;
+	u32_t channel_group = 0;
+	int i;
+
+	channel_config.enableInterruptOnConversionCompleted = true;
+#if defined(FSL_FEATURE_ADC16_HAS_DIFF_MODE) && FSL_FEATURE_ADC16_HAS_DIFF_MODE
+	channel_config.enableDifferentialConversion = false;
+#endif
+
+	for (i = 0; i < seq_table->num_entries; i++) {
+		if (entry->buffer_length < sizeof(data->result)) {
+			return -EINVAL;
+		}
+
+		channel_config.channelNumber = entry->channel_id;
+		ADC16_SetChannelConfig(base, channel_group, &channel_config);
+
+		data->channel_group = channel_group;
+
+		k_sem_take(&data->sync, K_FOREVER);
+
+		memcpy(entry->buffer, &data->result, sizeof(data->result));
+
+		entry++;
+	}
+
+	return 0;
+}
+
+static void mcux_adc16_isr(void *arg)
+{
+	struct device *dev = (struct device *)arg;
+	const struct mcux_adc16_config *config = dev->config->config_info;
+	struct mcux_adc16_data *data = dev->driver_data;
+	ADC_Type *base = config->base;
+	u32_t channel_group = data->channel_group;
+
+	data->result = ADC16_GetChannelConversionValue(base, channel_group);
+
+	k_sem_give(&data->sync);
+}
+
+static int mcux_adc16_init(struct device *dev)
+{
+	const struct mcux_adc16_config *config = dev->config->config_info;
+	struct mcux_adc16_data *data = dev->driver_data;
+	ADC_Type *base = config->base;
+	adc16_config_t adc_config;
+
+	k_sem_init(&data->sync, 0, UINT_MAX);
+
+	ADC16_GetDefaultConfig(&adc_config);
+	ADC16_Init(base, &adc_config);
+
+	ADC16_EnableHardwareTrigger(base, false);
+	ADC16_SetHardwareAverage(base, kADC16_HardwareAverageCount4);
+
+	config->irq_config_func(dev);
+
+	return 0;
+}
+
+static const struct adc_driver_api mcux_adc16_driver_api = {
+	.enable = mcux_adc16_enable,
+	.disable = mcux_adc16_disable,
+	.read = mcux_adc16_read,
+};
+
+#if CONFIG_ADC_0
+static void mcux_adc16_config_func_0(struct device *dev);
+
+static const struct mcux_adc16_config mcux_adc16_config_0 = {
+	.base = (ADC_Type *)CONFIG_ADC_0_BASE_ADDRESS,
+	.irq_config_func = mcux_adc16_config_func_0,
+};
+
+static struct mcux_adc16_data mcux_adc16_data_0;
+
+DEVICE_AND_API_INIT(mcux_adc16_0, CONFIG_ADC_0_NAME, &mcux_adc16_init,
+		    &mcux_adc16_data_0, &mcux_adc16_config_0,
+		    POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
+		    &mcux_adc16_driver_api);
+
+static void mcux_adc16_config_func_0(struct device *dev)
+{
+	IRQ_CONNECT(CONFIG_ADC_0_IRQ, CONFIG_ADC_0_IRQ_PRI,
+		    mcux_adc16_isr, DEVICE_GET(mcux_adc16_0), 0);
+
+	irq_enable(CONFIG_ADC_0_IRQ);
+}
+#endif /* CONFIG_ADC_0 */
+
+#if CONFIG_ADC_1
+static void mcux_adc16_config_func_1(struct device *dev);
+
+static const struct mcux_adc16_config mcux_adc16_config_1 = {
+	.base = (ADC_Type *)CONFIG_ADC_1_BASE_ADDRESS,
+	.irq_config_func = mcux_adc16_config_func_1,
+};
+
+static struct mcux_adc16_data mcux_adc16_data_1;
+
+DEVICE_AND_API_INIT(mcux_adc16_1, CONFIG_ADC_1_NAME, &mcux_adc16_init,
+		    &mcux_adc16_data_1, &mcux_adc16_config_1,
+		    POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
+		    &mcux_adc16_driver_api);
+
+static void mcux_adc16_config_func_1(struct device *dev)
+{
+	IRQ_CONNECT(CONFIG_ADC_1_IRQ, CONFIG_ADC_1_IRQ_PRI,
+		    mcux_adc16_isr, DEVICE_GET(mcux_adc16_1), 0);
+
+	irq_enable(CONFIG_ADC_1_IRQ);
+}
+#endif /* CONFIG_ADC_1 */

ext/hal/nxp/mcux/drivers/Makefile

@@ -4,6 +4,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+obj-$(CONFIG_ADC_MCUX_ADC16) += fsl_adc16.o
 obj-$(CONFIG_ETH_MCUX) += fsl_enet.o
 obj-$(CONFIG_I2C_MCUX) += fsl_i2c.o
 obj-$(CONFIG_RANDOM_MCUX_RNGA) += fsl_rnga.o