blob: d9dc542a5bf94d39ab6a2205bdb74dadcb61311c [file] [log] [blame]
/*
* Copyright (c) 2023 Antmicro <www.antmicro.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT silabs_gecko_iadc
#include <zephyr/drivers/adc.h>
#include <em_iadc.h>
#include <em_cmu.h>
#define ADC_CONTEXT_USES_KERNEL_TIMER
#include "adc_context.h"
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(iadc_gecko, CONFIG_ADC_LOG_LEVEL);
/* Number of channels available. */
#define GECKO_CHANNEL_COUNT 16
#define GECKO_INTERNAL_REFERENCE_mV 1210
#define GECKO_DATA_RES12BIT(DATA) ((DATA) & 0x0FFF)
struct adc_gecko_channel_config {
IADC_CfgAnalogGain_t gain;
IADC_CfgReference_t reference;
IADC_PosInput_t input_positive;
IADC_NegInput_t input_negative;
bool initialized;
};
struct adc_gecko_data {
const struct device *dev;
struct adc_context ctx;
uint16_t *buffer;
uint16_t *repeat_buffer;
uint32_t channels;
uint8_t channel_id;
struct adc_gecko_channel_config channel_config[GECKO_CHANNEL_COUNT];
};
struct adc_gecko_config {
IADC_Config_t config;
IADC_TypeDef *base;
void (*irq_cfg_func)(void);
};
static void adc_gecko_set_config(const struct device *dev)
{
struct adc_gecko_data *data = dev->data;
struct adc_gecko_channel_config *channel_config = NULL;
const struct adc_gecko_config *config = dev->config;
IADC_TypeDef *iadc = (IADC_TypeDef *)config->base;
IADC_InitSingle_t sInit = IADC_INITSINGLE_DEFAULT;
IADC_SingleInput_t initSingleInput = IADC_SINGLEINPUT_DEFAULT;
IADC_Init_t init = IADC_INIT_DEFAULT;
IADC_AllConfigs_t initAllConfigs = IADC_ALLCONFIGS_DEFAULT;
channel_config = &data->channel_config[data->channel_id];
initSingleInput.posInput = channel_config->input_positive;
initSingleInput.negInput = channel_config->input_negative;
initAllConfigs.configs[0].analogGain = channel_config->gain;
initAllConfigs.configs[0].reference = channel_config->reference;
IADC_init(iadc, &init, &initAllConfigs);
IADC_initSingle(iadc, &sInit, &initSingleInput);
}
static int adc_gecko_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_gecko_check_resolution(const struct adc_sequence *sequence)
{
int value = sequence->resolution;
/* Base resolution is on 12, it can be changed only up by oversampling */
if (value != 12) {
return -EINVAL;
}
return value;
}
static int start_read(const struct device *dev, const struct adc_sequence *sequence)
{
struct adc_gecko_data *data = dev->data;
uint32_t channels;
uint8_t channel_count;
uint8_t index;
int res;
/* Check if at least 1 channel is requested */
if (sequence->channels == 0) {
LOG_DBG("No channel requested");
return -EINVAL;
}
if (sequence->oversampling) {
LOG_ERR("Oversampling is not supported");
return -ENOTSUP;
}
/* Check resolution setting */
res = adc_gecko_check_resolution(sequence);
if (res < 0) {
return -EINVAL;
}
/* Verify all requested channels are initialized and store resolution */
channels = sequence->channels;
channel_count = 0;
while (channels) {
/* Iterate through all channels and check if they are initialized */
index = find_lsb_set(channels) - 1;
if (index >= GECKO_CHANNEL_COUNT) {
LOG_DBG("Requested channel index not available: %d", index);
return -EINVAL;
}
if (!data->channel_config[index].initialized) {
LOG_DBG("Channel not initialized");
return -EINVAL;
}
channel_count++;
channels &= ~BIT(index);
}
/* Check buffer size */
res = adc_gecko_check_buffer_size(sequence, channel_count);
if (res < 0) {
return res;
}
data->buffer = sequence->buffer;
adc_context_start_read(&data->ctx, sequence);
res = adc_context_wait_for_completion(&data->ctx);
return res;
}
static void adc_gecko_start_channel(const struct device *dev)
{
const struct adc_gecko_config *config = dev->config;
struct adc_gecko_data *data = dev->data;
IADC_TypeDef *iadc = (IADC_TypeDef *)config->base;
data->channel_id = find_lsb_set(data->channels) - 1;
LOG_DBG("Starting channel %d", data->channel_id);
adc_gecko_set_config(data->dev);
/* Enable single conversion interrupt */
IADC_enableInt(iadc, IADC_IEN_SINGLEDONE);
/* Start single conversion */
IADC_command(iadc, iadcCmdStartSingle);
}
static void adc_context_start_sampling(struct adc_context *ctx)
{
struct adc_gecko_data *data =
CONTAINER_OF(ctx, struct adc_gecko_data, ctx);
data->channels = ctx->sequence.channels;
data->repeat_buffer = data->buffer;
adc_gecko_start_channel(data->dev);
}
static void adc_context_update_buffer_pointer(struct adc_context *ctx,
bool repeat_sampling)
{
struct adc_gecko_data *data =
CONTAINER_OF(ctx, struct adc_gecko_data, ctx);
if (repeat_sampling) {
data->buffer = data->repeat_buffer;
}
}
static void adc_gecko_isr(void *arg)
{
const struct device *dev = (const struct device *)arg;
const struct adc_gecko_config *config = dev->config;
struct adc_gecko_data *data = dev->data;
IADC_TypeDef *iadc = config->base;
IADC_Result_t sample;
uint32_t flags, err;
/*
* IRQ is enabled only for SINGLEDONE. However, other
* interrupt flags - the ones singaling an error - may be
* set simultaneously with SINGLEDONE. We read & clear them
* to determine if conversion is successful or not.
*/
flags = IADC_getInt(iadc);
__ASSERT(flags & IADC_IF_SINGLEDONE,
"unexpected IADC IRQ (flags=0x%08x)!", flags);
err = flags & (IADC_IF_PORTALLOCERR |
IADC_IF_POLARITYERR |
IADC_IF_EM23ABORTERROR);
if (!err) {
sample = IADC_readSingleResult(iadc);
*data->buffer++ = GECKO_DATA_RES12BIT((uint16_t)sample.data);
data->channels &= ~BIT(data->channel_id);
if (data->channels) {
adc_gecko_start_channel(dev);
} else {
adc_context_on_sampling_done(&data->ctx, dev);
}
} else {
LOG_ERR("IADC conversion error, flags=%08x", err);
adc_context_complete(&data->ctx, -EIO);
}
IADC_clearInt(iadc, IADC_IF_SINGLEDONE | err);
}
static int adc_gecko_read(const struct device *dev,
const struct adc_sequence *sequence)
{
struct adc_gecko_data *data = dev->data;
int error;
adc_context_lock(&data->ctx, false, NULL);
error = start_read(dev, sequence);
adc_context_release(&data->ctx, error);
return error;
}
#ifdef CONFIG_ADC_ASYNC
static int adc_gecko_read_async(const struct device *dev,
const struct adc_sequence *sequence,
struct k_poll_signal *async)
{
struct adc_gecko_data *data = dev->data;
int error;
adc_context_lock(&data->ctx, true, async);
error = start_read(dev, sequence);
adc_context_release(&data->ctx, error);
return error;
}
#endif
static void adc_gecko_gpio_busalloc_pos(IADC_PosInput_t input)
{
uint32_t port = ((input << _IADC_SCAN_PINPOS_SHIFT) &
_IADC_SCAN_PORTPOS_MASK) >> _IADC_SCAN_PORTPOS_SHIFT;
uint32_t pin = ((input << _IADC_SCAN_PINPOS_SHIFT) &
_IADC_SCAN_PINPOS_MASK) >> _IADC_SCAN_PINPOS_SHIFT;
switch (port) {
case _IADC_SCAN_PORTPOS_PORTA:
if (pin & 1) {
GPIO->ABUSALLOC |= GPIO_ABUSALLOC_AODD0_ADC0;
} else {
GPIO->ABUSALLOC |= GPIO_ABUSALLOC_AEVEN0_ADC0;
}
break;
case _IADC_SCAN_PORTPOS_PORTB:
if (pin & 1) {
GPIO->BBUSALLOC |= GPIO_BBUSALLOC_BODD0_ADC0;
} else {
GPIO->BBUSALLOC |= GPIO_BBUSALLOC_BEVEN0_ADC0;
}
break;
case _IADC_SCAN_PORTPOS_PORTC:
case _IADC_SCAN_PORTPOS_PORTD:
if (pin & 1) {
GPIO->CDBUSALLOC |= GPIO_CDBUSALLOC_CDODD0_ADC0;
} else {
GPIO->CDBUSALLOC |= GPIO_CDBUSALLOC_CDEVEN0_ADC0;
}
break;
default:
}
}
static void adc_gecko_gpio_busalloc_neg(IADC_NegInput_t input)
{
uint32_t port = ((input << _IADC_SCAN_PINNEG_SHIFT) &
_IADC_SCAN_PORTNEG_MASK) >> _IADC_SCAN_PORTNEG_SHIFT;
uint32_t pin = ((input << _IADC_SCAN_PINNEG_SHIFT) &
_IADC_SCAN_PINNEG_MASK) >> _IADC_SCAN_PINNEG_SHIFT;
switch (port) {
case _IADC_SCAN_PORTNEG_PORTA:
if (pin & 1) {
GPIO->ABUSALLOC |= GPIO_ABUSALLOC_AODD0_ADC0;
} else {
GPIO->ABUSALLOC |= GPIO_ABUSALLOC_AEVEN0_ADC0;
}
break;
case _IADC_SCAN_PORTNEG_PORTB:
if (pin & 1) {
GPIO->BBUSALLOC |= GPIO_BBUSALLOC_BODD0_ADC0;
} else {
GPIO->BBUSALLOC |= GPIO_BBUSALLOC_BEVEN0_ADC0;
}
break;
case _IADC_SCAN_PORTNEG_PORTC:
case _IADC_SCAN_PORTNEG_PORTD:
if (pin & 1) {
GPIO->CDBUSALLOC |= GPIO_CDBUSALLOC_CDODD0_ADC0;
} else {
GPIO->CDBUSALLOC |= GPIO_CDBUSALLOC_CDEVEN0_ADC0;
}
break;
default:
}
}
static int adc_gecko_channel_setup(const struct device *dev,
const struct adc_channel_cfg *channel_cfg)
{
struct adc_gecko_data *data = dev->data;
struct adc_gecko_channel_config *channel_config = NULL;
if (channel_cfg->channel_id < GECKO_CHANNEL_COUNT) {
channel_config = &data->channel_config[channel_cfg->channel_id];
} else {
LOG_DBG("Requested channel index not available: %d", channel_cfg->channel_id);
return -EINVAL;
}
channel_config->initialized = false;
channel_config->input_positive = channel_cfg->input_positive;
if (channel_cfg->differential) {
channel_config->input_negative = channel_cfg->input_negative;
} else {
channel_config->input_negative = iadcNegInputGnd;
}
/* Setup input */
switch (channel_cfg->gain) {
#if defined(_IADC_CFG_ANALOGGAIN_ANAGAIN0P25)
case ADC_GAIN_1_4:
channel_config->gain = iadcCfgAnalogGain0P25x;
break;
#endif
case ADC_GAIN_1_2:
channel_config->gain = iadcCfgAnalogGain0P5x;
break;
case ADC_GAIN_1:
channel_config->gain = iadcCfgAnalogGain1x;
break;
case ADC_GAIN_2:
channel_config->gain = iadcCfgAnalogGain2x;
break;
case ADC_GAIN_3:
channel_config->gain = iadcCfgAnalogGain3x;
break;
case ADC_GAIN_4:
channel_config->gain = iadcCfgAnalogGain4x;
break;
default:
LOG_ERR("unsupported channel gain '%d'", channel_cfg->gain);
return -ENOTSUP;
}
/* Setup reference */
switch (channel_cfg->reference) {
case ADC_REF_VDD_1:
channel_config->reference = iadcCfgReferenceVddx;
break;
case ADC_REF_INTERNAL:
channel_config->reference = iadcCfgReferenceInt1V2;
break;
#if defined(_IADC_CFG_REFSEL_VREF2P5)
case ADC_REF_EXTERNAL1:
channel_config->reference = iadcCfgReferenceExt2V5;
break;
#endif
case ADC_REF_EXTERNAL0:
channel_config->reference = iadcCfgReferenceExt1V25;
break;
default:
LOG_ERR("unsupported channel reference type '%d'",
channel_cfg->reference);
return -ENOTSUP;
}
/* Setup GPIO xBUSALLOC registers if channel uses GPIO pin */
adc_gecko_gpio_busalloc_pos(channel_config->input_positive);
adc_gecko_gpio_busalloc_neg(channel_config->input_negative);
channel_config->initialized = true;
LOG_DBG("Channel setup succeeded!");
return 0;
}
static int adc_gecko_init(const struct device *dev)
{
const struct adc_gecko_config *config = dev->config;
struct adc_gecko_data *data = dev->data;
CMU_ClockEnable(cmuClock_IADC0, true);
/* Select clock for IADC */
CMU_ClockSelectSet(cmuClock_IADCCLK, cmuSelect_FSRCO); /* FSRCO - 20MHz */
data->dev = dev;
config->irq_cfg_func();
adc_context_unlock_unconditionally(&data->ctx);
return 0;
}
static const struct adc_driver_api api_gecko_adc_driver_api = {
.channel_setup = adc_gecko_channel_setup,
.read = adc_gecko_read,
#ifdef CONFIG_ADC_ASYNC
.read_async = adc_gecko_read_async,
#endif
.ref_internal = GECKO_INTERNAL_REFERENCE_mV,
};
#define GECKO_IADC_INIT(n) \
\
static void adc_gecko_config_func_##n(void); \
\
const static struct adc_gecko_config adc_gecko_config_##n = { \
.base = (IADC_TypeDef *)DT_INST_REG_ADDR(n),\
.irq_cfg_func = adc_gecko_config_func_##n, \
}; \
static struct adc_gecko_data adc_gecko_data_##n = { \
ADC_CONTEXT_INIT_TIMER(adc_gecko_data_##n, ctx), \
ADC_CONTEXT_INIT_LOCK(adc_gecko_data_##n, ctx), \
ADC_CONTEXT_INIT_SYNC(adc_gecko_data_##n, ctx), \
}; \
static void adc_gecko_config_func_##n(void) \
{ \
IRQ_CONNECT(DT_INST_IRQN(n), \
DT_INST_IRQ(n, priority), \
adc_gecko_isr, DEVICE_DT_INST_GET(n), 0); \
irq_enable(DT_INST_IRQN(n)); \
}; \
DEVICE_DT_INST_DEFINE(n, \
&adc_gecko_init, NULL, \
&adc_gecko_data_##n, &adc_gecko_config_##n,\
POST_KERNEL, CONFIG_ADC_INIT_PRIORITY, \
&api_gecko_adc_driver_api);
DT_INST_FOREACH_STATUS_OKAY(GECKO_IADC_INIT)