zephyr/drivers/adc/adc_ambiq.c

440 lines
14 KiB
C

/*
* Copyright (c) 2024 Ambiq Micro Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT ambiq_adc
#include <zephyr/drivers/adc.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/pm/device.h>
#include <zephyr/pm/device_runtime.h>
#include <zephyr/kernel.h>
#define ADC_CONTEXT_USES_KERNEL_TIMER
#include "adc_context.h"
/* ambiq-sdk includes */
#include <am_mcu_apollo.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(adc_ambiq, CONFIG_ADC_LOG_LEVEL);
typedef int (*ambiq_adc_pwr_func_t)(void);
#define PWRCTRL_MAX_WAIT_US 5
/* Number of slots available. */
#define AMBIQ_ADC_SLOT_NUMBER AM_HAL_ADC_MAX_SLOTS
struct adc_ambiq_config {
uint32_t base;
int size;
uint8_t num_channels;
void (*irq_config_func)(void);
const struct pinctrl_dev_config *pin_cfg;
ambiq_adc_pwr_func_t pwr_func;
};
struct adc_ambiq_data {
struct adc_context ctx;
void *adcHandle;
uint16_t *buffer;
uint16_t *repeat_buffer;
uint8_t active_channels;
};
static int adc_ambiq_set_resolution(am_hal_adc_slot_prec_e *prec, uint8_t adc_resolution)
{
switch (adc_resolution) {
case 8:
*prec = AM_HAL_ADC_SLOT_8BIT;
break;
case 10:
*prec = AM_HAL_ADC_SLOT_10BIT;
break;
case 12:
*prec = AM_HAL_ADC_SLOT_12BIT;
break;
#if !defined(CONFIG_SOC_SERIES_APOLLO4X)
case 14:
*prec = AM_HAL_ADC_SLOT_14BIT;
break;
#endif
default:
return -ENOTSUP;
}
return 0;
}
static int adc_ambiq_slot_config(const struct device *dev, const struct adc_sequence *sequence,
am_hal_adc_slot_chan_e channel, uint32_t ui32SlotNumber)
{
struct adc_ambiq_data *data = dev->data;
am_hal_adc_slot_config_t ADCSlotConfig;
if (adc_ambiq_set_resolution(&ADCSlotConfig.ePrecisionMode, sequence->resolution) != 0) {
LOG_ERR("unsupported resolution %d", sequence->resolution);
return -ENOTSUP;
}
/* Set up an ADC slot */
ADCSlotConfig.eMeasToAvg = AM_HAL_ADC_SLOT_AVG_1;
ADCSlotConfig.eChannel = channel;
ADCSlotConfig.bWindowCompare = false;
ADCSlotConfig.bEnabled = true;
#if defined(CONFIG_SOC_SERIES_APOLLO4X)
ADCSlotConfig.ui32TrkCyc = AM_HAL_ADC_MIN_TRKCYC;
#endif
if (AM_HAL_STATUS_SUCCESS !=
am_hal_adc_configure_slot(data->adcHandle, ui32SlotNumber, &ADCSlotConfig)) {
LOG_ERR("configuring ADC Slot 0 failed.\n");
return -ENODEV;
}
return 0;
}
static void adc_ambiq_isr(const struct device *dev)
{
struct adc_ambiq_data *data = dev->data;
uint32_t ui32IntMask;
uint32_t ui32NumSamples;
am_hal_adc_sample_t Sample;
/* Read the interrupt status. */
am_hal_adc_interrupt_status(data->adcHandle, &ui32IntMask, true);
/* Clear the ADC interrupt.*/
am_hal_adc_interrupt_clear(data->adcHandle, ui32IntMask);
/*
* If we got a conversion completion interrupt (which should be our only
* ADC interrupt), go ahead and read the data.
*/
if (ui32IntMask & AM_HAL_ADC_INT_CNVCMP) {
for (uint32_t i = 0; i < data->active_channels; i++) {
/* Read the value from the FIFO. */
ui32NumSamples = 1;
am_hal_adc_samples_read(data->adcHandle, false, NULL, &ui32NumSamples,
&Sample);
*data->buffer++ = Sample.ui32Sample;
}
adc_context_on_sampling_done(&data->ctx, dev);
}
}
static int adc_ambiq_check_buffer_size(const struct adc_sequence *sequence, uint8_t active_channels)
{
size_t needed_buffer_size;
needed_buffer_size = active_channels * sizeof(uint16_t);
if (sequence->options) {
needed_buffer_size *= (1 + sequence->options->extra_samplings);
}
if (sequence->buffer_size < needed_buffer_size) {
LOG_DBG("Provided buffer is too small (%u/%u)", sequence->buffer_size,
needed_buffer_size);
return -ENOMEM;
}
return 0;
}
static int adc_ambiq_start_read(const struct device *dev, const struct adc_sequence *sequence)
{
struct adc_ambiq_data *data = dev->data;
const struct adc_ambiq_config *cfg = dev->config;
uint8_t channel_id = 0;
uint32_t channels = 0;
uint8_t active_channels = 0;
uint8_t slot_index;
int error = 0;
if (sequence->channels & ~BIT_MASK(cfg->num_channels)) {
LOG_ERR("Incorrect channels, bitmask 0x%x", sequence->channels);
return -EINVAL;
}
if (sequence->channels == 0UL) {
LOG_ERR("No channel selected");
return -EINVAL;
}
error = adc_ambiq_check_buffer_size(sequence, active_channels);
if (error < 0) {
return error;
}
active_channels = POPCOUNT(sequence->channels);
if (active_channels > AMBIQ_ADC_SLOT_NUMBER) {
LOG_ERR("Too many channels for sequencer. Max: %d", AMBIQ_ADC_SLOT_NUMBER);
return -ENOTSUP;
}
channels = sequence->channels;
for (slot_index = 0; slot_index < active_channels; slot_index++) {
channel_id = find_lsb_set(channels) - 1;
error = adc_ambiq_slot_config(dev, sequence, channel_id, slot_index);
if (error < 0) {
return error;
}
channels &= ~BIT(channel_id);
}
__ASSERT_NO_MSG(channels == 0);
/* Enable the ADC. */
am_hal_adc_enable(data->adcHandle);
data->active_channels = active_channels;
data->buffer = sequence->buffer;
/* Start ADC conversion */
adc_context_start_read(&data->ctx, sequence);
error = adc_context_wait_for_completion(&data->ctx);
return error;
}
static int adc_ambiq_read(const struct device *dev, const struct adc_sequence *sequence)
{
struct adc_ambiq_data *data = dev->data;
int error = 0;
error = pm_device_runtime_get(dev);
if (error < 0) {
LOG_ERR("pm_device_runtime_get failed: %d", error);
}
adc_context_lock(&data->ctx, false, NULL);
error = adc_ambiq_start_read(dev, sequence);
adc_context_release(&data->ctx, error);
int ret = error;
error = pm_device_runtime_put(dev);
if (error < 0) {
LOG_ERR("pm_device_runtime_put failed: %d", error);
}
error = ret;
return error;
}
static int adc_ambiq_channel_setup(const struct device *dev, const struct adc_channel_cfg *chan_cfg)
{
const struct adc_ambiq_config *cfg = dev->config;
if (chan_cfg->channel_id >= cfg->num_channels) {
LOG_ERR("unsupported channel id '%d'", chan_cfg->channel_id);
return -ENOTSUP;
}
if (chan_cfg->gain != ADC_GAIN_1) {
LOG_ERR("Gain is not valid");
return -ENOTSUP;
}
if (chan_cfg->reference != ADC_REF_INTERNAL) {
LOG_ERR("Reference is not valid");
return -ENOTSUP;
}
if (chan_cfg->acquisition_time != ADC_ACQ_TIME_DEFAULT) {
LOG_ERR("unsupported acquisition_time '%d'", chan_cfg->acquisition_time);
return -ENOTSUP;
}
if (chan_cfg->differential) {
LOG_ERR("Differential sampling not supported");
return -ENOTSUP;
}
return 0;
}
static void adc_context_update_buffer_pointer(struct adc_context *ctx, bool repeat_sampling)
{
struct adc_ambiq_data *data = CONTAINER_OF(ctx, struct adc_ambiq_data, ctx);
if (repeat_sampling) {
data->buffer = data->repeat_buffer;
}
}
static void adc_context_start_sampling(struct adc_context *ctx)
{
struct adc_ambiq_data *data = CONTAINER_OF(ctx, struct adc_ambiq_data, ctx);
data->repeat_buffer = data->buffer;
/*Trigger the ADC*/
am_hal_adc_sw_trigger(data->adcHandle);
}
static int adc_ambiq_init(const struct device *dev)
{
struct adc_ambiq_data *data = dev->data;
const struct adc_ambiq_config *cfg = dev->config;
am_hal_adc_config_t ADCConfig;
int ret;
/* Initialize the ADC and get the handle*/
if (AM_HAL_STATUS_SUCCESS !=
am_hal_adc_initialize((cfg->base - ADC_BASE) / (cfg->size * 4), &data->adcHandle)) {
ret = -ENODEV;
LOG_ERR("Faile to initialize ADC, code:%d", ret);
return ret;
}
/* power on ADC*/
ret = cfg->pwr_func();
/* Set up the ADC configuration parameters. These settings are reasonable
* for accurate measurements at a low sample rate.
*/
#if !defined(CONFIG_SOC_SERIES_APOLLO4X)
ADCConfig.eClock = AM_HAL_ADC_CLKSEL_HFRC;
ADCConfig.eReference = AM_HAL_ADC_REFSEL_INT_1P5;
#else
ADCConfig.eClock = AM_HAL_ADC_CLKSEL_HFRC_24MHZ;
ADCConfig.eRepeatTrigger = AM_HAL_ADC_RPTTRIGSEL_TMR,
#endif
ADCConfig.ePolarity = AM_HAL_ADC_TRIGPOL_RISING;
ADCConfig.eTrigger = AM_HAL_ADC_TRIGSEL_SOFTWARE;
ADCConfig.eClockMode = AM_HAL_ADC_CLKMODE_LOW_POWER;
ADCConfig.ePowerMode = AM_HAL_ADC_LPMODE0;
ADCConfig.eRepeat = AM_HAL_ADC_SINGLE_SCAN;
if (AM_HAL_STATUS_SUCCESS != am_hal_adc_configure(data->adcHandle, &ADCConfig)) {
ret = -ENODEV;
LOG_ERR("Configuring ADC failed, code:%d", ret);
return ret;
}
ret = pinctrl_apply_state(cfg->pin_cfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
return ret;
}
/* Enable the ADC interrupts in the ADC. */
cfg->irq_config_func();
am_hal_adc_interrupt_enable(data->adcHandle, AM_HAL_ADC_INT_CNVCMP);
adc_context_unlock_unconditionally(&data->ctx);
return 0;
}
#ifdef CONFIG_ADC_ASYNC
static int adc_ambiq_read_async(const struct device *dev, const struct adc_sequence *sequence,
struct k_poll_signal *async)
{
struct adc_ambiq_data *data = dev->data;
int error = 0;
error = pm_device_runtime_get(dev);
if (error < 0) {
LOG_ERR("pm_device_runtime_get failed: %d", error);
}
adc_context_lock(&data->ctx, true, async);
error = adc_ambiq_start_read(dev, sequence);
adc_context_release(&data->ctx, error);
int ret = error;
error = pm_device_runtime_put(dev);
if (error < 0) {
LOG_ERR("pm_device_runtime_put failed: %d", error);
}
error = ret;
return error;
}
#endif
#ifdef CONFIG_PM_DEVICE
static int adc_ambiq_pm_action(const struct device *dev, enum pm_device_action action)
{
struct adc_ambiq_data *data = dev->data;
uint32_t ret = 0;
am_hal_sysctrl_power_state_e status;
switch (action) {
case PM_DEVICE_ACTION_RESUME:
status = AM_HAL_SYSCTRL_WAKE;
break;
case PM_DEVICE_ACTION_SUSPEND:
status = AM_HAL_SYSCTRL_DEEPSLEEP;
break;
default:
return -ENOTSUP;
}
ret = am_hal_adc_power_control(data->adcHandle, status, true);
if (ret != AM_HAL_STATUS_SUCCESS) {
return -EPERM;
} else {
return 0;
}
}
#endif /* CONFIG_PM_DEVICE */
#ifdef CONFIG_ADC_ASYNC
#define ADC_AMBIQ_DRIVER_API(n) \
static const struct adc_driver_api adc_ambiq_driver_api_##n = { \
.channel_setup = adc_ambiq_channel_setup, \
.read = adc_ambiq_read, \
.read_async = adc_ambiq_read_async, \
.ref_internal = DT_INST_PROP(n, internal_vref_mv), \
};
#else
#define ADC_AMBIQ_DRIVER_API(n) \
static const struct adc_driver_api adc_ambiq_driver_api_##n = { \
.channel_setup = adc_ambiq_channel_setup, \
.read = adc_ambiq_read, \
.ref_internal = DT_INST_PROP(n, internal_vref_mv), \
};
#endif
#define ADC_AMBIQ_INIT(n) \
PINCTRL_DT_INST_DEFINE(n); \
ADC_AMBIQ_DRIVER_API(n); \
static int pwr_on_ambiq_adc_##n(void) \
{ \
uint32_t addr = DT_REG_ADDR(DT_INST_PHANDLE(n, ambiq_pwrcfg)) + \
DT_INST_PHA(n, ambiq_pwrcfg, offset); \
sys_write32((sys_read32(addr) | DT_INST_PHA(n, ambiq_pwrcfg, mask)), addr); \
k_busy_wait(PWRCTRL_MAX_WAIT_US); \
return 0; \
} \
static void adc_irq_config_func_##n(void) \
{ \
IRQ_CONNECT(DT_INST_IRQN(n), DT_INST_IRQ(n, priority), adc_ambiq_isr, \
DEVICE_DT_INST_GET(n), 0); \
irq_enable(DT_INST_IRQN(n)); \
}; \
static struct adc_ambiq_data adc_ambiq_data_##n = { \
ADC_CONTEXT_INIT_TIMER(adc_ambiq_data_##n, ctx), \
ADC_CONTEXT_INIT_LOCK(adc_ambiq_data_##n, ctx), \
ADC_CONTEXT_INIT_SYNC(adc_ambiq_data_##n, ctx), \
}; \
const static struct adc_ambiq_config adc_ambiq_config_##n = { \
.base = DT_INST_REG_ADDR(n), \
.size = DT_INST_REG_SIZE(n), \
.num_channels = DT_PROP(DT_DRV_INST(n), channel_count), \
.irq_config_func = adc_irq_config_func_##n, \
.pin_cfg = PINCTRL_DT_INST_DEV_CONFIG_GET(n), \
.pwr_func = pwr_on_ambiq_adc_##n, \
}; \
PM_DEVICE_DT_INST_DEFINE(n, adc_ambiq_pm_action); \
DEVICE_DT_INST_DEFINE(n, &adc_ambiq_init, PM_DEVICE_DT_INST_GET(n), &adc_ambiq_data_##n, \
&adc_ambiq_config_##n, POST_KERNEL, CONFIG_ADC_INIT_PRIORITY, \
&adc_ambiq_driver_api_##n);
DT_INST_FOREACH_STATUS_OKAY(ADC_AMBIQ_INIT)