blob: 51b0eb93bbba243fe95ecdd1a99f2ae648f6ba7b [file] [log] [blame]
/*
* Copyright (c) 2024 ENE Technology Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT ene_kb1200_adc
#include <zephyr/kernel.h>
#include <zephyr/drivers/adc.h>
#include <zephyr/drivers/pinctrl.h>
#include <errno.h>
#include <reg/adc.h>
#define ADC_CONTEXT_USES_KERNEL_TIMER
#include "adc_context.h"
struct adc_kb1200_config {
/* ADC Register base address */
struct adc_regs *adc;
/* Pin control */
const struct pinctrl_dev_config *pcfg;
};
struct adc_kb1200_data {
struct adc_context ctx;
const struct device *adc_dev;
uint16_t *buffer;
uint16_t *repeat_buffer;
uint16_t *buf_end;
};
/* ADC local functions */
static bool adc_kb1200_validate_buffer_size(const struct adc_sequence *sequence)
{
int chan_count = 0;
size_t buff_need;
uint32_t chan_mask;
for (chan_mask = 0x80; chan_mask != 0; chan_mask >>= 1) {
if (chan_mask & sequence->channels) {
chan_count++;
}
}
buff_need = chan_count * sizeof(uint16_t);
if (sequence->options) {
buff_need *= 1 + sequence->options->extra_samplings;
}
if (buff_need > sequence->buffer_size) {
return false;
}
return true;
}
/* ADC Sample Flow (by using adc_context.h api function)
* 1. Start ADC sampling (set up flag ctx->sync)
* adc_context_start_read() -> adc_context_start_sampling()
* 2. Wait ADC sample finish (by monitor flag ctx->sync)
* adc_context_wait_for_completion
* 3. Finish ADC sample (isr clear flag ctx->sync)
* adc_context_on_sampling_done -> adc_context_complete
*/
static int adc_kb1200_start_read(const struct device *dev, const struct adc_sequence *sequence)
{
const struct adc_kb1200_config *config = dev->config;
struct adc_kb1200_data *data = dev->data;
int error = 0;
if (!sequence->channels || (sequence->channels & ~BIT_MASK(ADC_MAX_CHAN))) {
printk("Invalid ADC channels.\n");
return -EINVAL;
}
/* Fixed 10 bit resolution of ene ADC */
if (sequence->resolution != ADC_RESOLUTION) {
printk("Unfixed 10 bit ADC resolution.\n");
return -ENOTSUP;
}
/* Check sequence->buffer_size is enough */
if (!adc_kb1200_validate_buffer_size(sequence)) {
printk("ADC buffer size too small.\n");
return -ENOMEM;
}
/* assign record buffer pointer */
data->buffer = sequence->buffer;
data->buf_end = data->buffer + sequence->buffer_size / sizeof(uint16_t);
/* store device for adc_context_start_read() */
data->adc_dev = dev;
/* Inform adc start sampling */
adc_context_start_read(&data->ctx, sequence);
/* Since kb1200 adc has no irq. So need polling the adc conversion
* flag to be valid, then record adc value.
*/
uint32_t channels = (config->adc->ADCCFG & ADC_CHANNEL_BIT_MASK) >> ADC_CHANNEL_BIT_POS;
while (channels) {
int count;
int ch_num;
count = 0;
ch_num = find_lsb_set(channels) - 1;
/* wait valid flag */
while (config->adc->ADCDAT[ch_num] & ADC_INVALID_VALUE) {
k_busy_wait(ADC_WAIT_TIME);
count++;
if (count >= ADC_WAIT_CNT) {
printk("ADC busy timeout...\n");
error = -EBUSY;
break;
}
}
/* check buffer size is enough then record adc value */
if (data->buffer < data->buf_end) {
*data->buffer = (uint16_t)(config->adc->ADCDAT[ch_num]);
data->buffer++;
} else {
error = -EINVAL;
break;
}
/* clear completed channel */
channels &= ~BIT(ch_num);
}
/* Besause polling the adc conversion flag. don't need wait_for_completion*/
/* Inform adc sampling is done */
adc_context_on_sampling_done(&data->ctx, dev);
return error;
}
/* ADC api functions */
static int adc_kb1200_channel_setup(const struct device *dev,
const struct adc_channel_cfg *channel_cfg)
{
if (channel_cfg->channel_id >= ADC_MAX_CHAN) {
printk("Invalid channel %d.\n", channel_cfg->channel_id);
return -EINVAL;
}
if (channel_cfg->acquisition_time != ADC_ACQ_TIME_DEFAULT) {
printk("Unsupported channel acquisition time.\n");
return -ENOTSUP;
}
if (channel_cfg->differential) {
printk("Differential channels are not supported.\n");
return -ENOTSUP;
}
if (channel_cfg->gain != ADC_GAIN_1) {
printk("Unsupported channel gain %d.\n", channel_cfg->gain);
return -ENOTSUP;
}
if (channel_cfg->reference != ADC_REF_INTERNAL) {
printk("Unsupported channel reference.\n");
return -ENOTSUP;
}
printk("ADC channel %d configured.\n", channel_cfg->channel_id);
return 0;
}
static int adc_kb1200_read(const struct device *dev, const struct adc_sequence *sequence)
{
struct adc_kb1200_data *data = dev->data;
int error;
adc_context_lock(&data->ctx, false, NULL);
error = adc_kb1200_start_read(dev, sequence);
adc_context_release(&data->ctx, error);
return error;
}
#if defined(CONFIG_ADC_ASYNC)
static int adc_kb1200_read_async(const struct device *dev, const struct adc_sequence *sequence,
struct k_poll_signal *async)
{
struct adc_kb1200_data *data = dev->data;
int error;
adc_context_lock(&data->ctx, true, async);
error = adc_kb1200_start_read(dev, sequence);
adc_context_release(&data->ctx, error);
return error;
}
#endif /* CONFIG_ADC_ASYNC */
/* ADC api function (using by adc_context.H function) */
static void adc_context_start_sampling(struct adc_context *ctx)
{
struct adc_kb1200_data *data = CONTAINER_OF(ctx, struct adc_kb1200_data, ctx);
const struct device *dev = data->adc_dev;
const struct adc_kb1200_config *config = dev->config;
data->repeat_buffer = data->buffer;
config->adc->ADCCFG = (config->adc->ADCCFG & ~ADC_CHANNEL_BIT_MASK) |
(ctx->sequence.channels << ADC_CHANNEL_BIT_POS);
config->adc->ADCCFG |= ADC_FUNCTION_ENABLE;
}
static void adc_context_update_buffer_pointer(struct adc_context *ctx, bool repeat_sampling)
{
struct adc_kb1200_data *data = CONTAINER_OF(ctx, struct adc_kb1200_data, ctx);
if (repeat_sampling) {
data->buffer = data->repeat_buffer;
}
}
struct adc_driver_api adc_kb1200_api = {
.channel_setup = adc_kb1200_channel_setup,
.read = adc_kb1200_read,
.ref_internal = ADC_VREF_ANALOG,
#if defined(CONFIG_ADC_ASYNC)
.read_async = adc_kb1200_read_async,
#endif
};
static int adc_kb1200_init(const struct device *dev)
{
const struct adc_kb1200_config *config = dev->config;
struct adc_kb1200_data *data = dev->data;
int ret;
adc_context_unlock_unconditionally(&data->ctx);
/* Configure pin-mux for ADC device */
ret = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
printk("ADC pinctrl setup failed (%d).\n", ret);
return ret;
}
return 0;
}
#define ADC_KB1200_DEVICE(inst) \
PINCTRL_DT_INST_DEFINE(inst); \
static struct adc_kb1200_data adc_kb1200_data_##inst = { \
ADC_CONTEXT_INIT_TIMER(adc_kb1200_data_##inst, ctx), \
ADC_CONTEXT_INIT_LOCK(adc_kb1200_data_##inst, ctx), \
ADC_CONTEXT_INIT_SYNC(adc_kb1200_data_##inst, ctx), \
}; \
static const struct adc_kb1200_config adc_kb1200_config_##inst = { \
.adc = (struct adc_regs *)DT_INST_REG_ADDR(inst), \
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(inst), \
}; \
DEVICE_DT_INST_DEFINE(inst, &adc_kb1200_init, NULL, &adc_kb1200_data_##inst, \
&adc_kb1200_config_##inst, PRE_KERNEL_1, \
CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &adc_kb1200_api);
DT_INST_FOREACH_STATUS_OKAY(ADC_KB1200_DEVICE)