esp-idf/components/esp_driver_dac/dac_continuous.c

637 wiersze
25 KiB
C

/*
* SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdatomic.h>
#include <string.h>
#include <sys/queue.h>
#include "freertos/FreeRTOS.h"
#include "freertos/queue.h"
#include "freertos/semphr.h"
#include "freertos/idf_additions.h"
#include "sdkconfig.h"
#include "rom/lldesc.h"
#include "soc/soc_caps.h"
#include "driver/dac_continuous.h"
#include "dac_priv_common.h"
#include "dac_priv_dma.h"
#if CONFIG_DAC_ENABLE_DEBUG_LOG
// The local log level must be defined before including esp_log.h
// Set the maximum log level for this source file
#define LOG_LOCAL_LEVEL ESP_LOG_DEBUG
#endif
#include "esp_check.h"
#if CONFIG_PM_ENABLE
#include "esp_pm.h"
#endif
#define DAC_DMA_MAX_BUF_SIZE 4092 // Max DMA buffer size is 4095 but better to align with 4 bytes, so set 4092 here
#if CONFIG_DAC_ISR_IRAM_SAFE || CONFIG_DAC_CTRL_FUNC_IN_IRAM
#define DAC_MEM_ALLOC_CAPS (MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT)
#else
#define DAC_MEM_ALLOC_CAPS MALLOC_CAP_DEFAULT
#endif
#if CONFIG_DAC_ISR_IRAM_SAFE
#define DAC_INTR_ALLOC_FLAGS (ESP_INTR_FLAG_LOWMED | ESP_INTR_FLAG_IRAM | ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_SHARED)
#else
#define DAC_INTR_ALLOC_FLAGS (ESP_INTR_FLAG_LOWMED | ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_SHARED)
#endif
#define DAC_DMA_ALLOC_CAPS (MALLOC_CAP_INTERNAL | MALLOC_CAP_DMA)
#define DAC_STAILQ_REMOVE(head, elm, type, field) do { \
if ((head)->stqh_first == (elm)) { \
STAILQ_REMOVE_HEAD((head), field); \
} else { \
struct type *curelm = (head)->stqh_first; \
while (curelm->field.stqe_next != (elm) && \
curelm->field.stqe_next != NULL) \
curelm = curelm->field.stqe_next; \
if (curelm->field.stqe_next && (curelm->field.stqe_next = \
curelm->field.stqe_next->field.stqe_next) == NULL) \
(head)->stqh_last = &(curelm)->field.stqe_next; \
} \
} while (/*CONSTCOND*/0)
struct dac_continuous_s {
uint32_t chan_cnt;
dac_continuous_config_t cfg;
atomic_bool is_enabled;
atomic_bool is_cyclic;
atomic_bool is_running;
atomic_bool is_async;
intr_handle_t intr_handle; /* Interrupt handle */
#if CONFIG_PM_ENABLE
esp_pm_lock_handle_t pm_lock;
#endif
SemaphoreHandle_t mutex;
QueueHandle_t desc_pool; /* The pool of available descriptors
* The descriptors in the pool are not linked in to pending chain */
lldesc_t **desc;
uint8_t **bufs;
STAILQ_HEAD(desc_chain_s, lldesc_s) head; /* Head of the descriptor chain
* The descriptors in the chain are pending to be sent or sending now */
dac_event_callbacks_t cbs; /* Interrupt callbacks */
void *user_data;
};
static const char *TAG = "dac_continuous";
static bool s_dma_in_use = false;
static portMUX_TYPE desc_spinlock = portMUX_INITIALIZER_UNLOCKED;
#define DESC_ENTER_CRITICAL() portENTER_CRITICAL(&desc_spinlock)
#define DESC_EXIT_CRITICAL() portEXIT_CRITICAL(&desc_spinlock)
#define DESC_ENTER_CRITICAL_ISR() portENTER_CRITICAL_ISR(&desc_spinlock)
#define DESC_EXIT_CRITICAL_ISR() portEXIT_CRITICAL_ISR(&desc_spinlock)
static void s_dac_free_dma_desc(dac_continuous_handle_t handle)
{
STAILQ_INIT(&handle->head);
if (handle->desc != NULL) {
if (handle->desc[0]) {
free(handle->desc[0]);
}
free(handle->desc);
handle->desc = NULL;
}
if (handle->bufs != NULL) {
for (int i = 0; i < handle->cfg.desc_num; i++) {
if (handle->bufs[i]) {
free(handle->bufs[i]);
handle->bufs[i] = NULL;
}
}
free(handle->bufs);
handle->bufs = NULL;
}
}
static esp_err_t s_dac_alloc_dma_desc(dac_continuous_handle_t handle)
{
esp_err_t ret = ESP_OK;
STAILQ_INIT(&handle->head);
handle->desc = (lldesc_t **) heap_caps_calloc(handle->cfg.desc_num, sizeof(lldesc_t *), DAC_DMA_ALLOC_CAPS);
ESP_RETURN_ON_FALSE(handle->desc, ESP_ERR_NO_MEM, TAG, "failed to allocate dma descriptor array");
handle->bufs = (uint8_t **) heap_caps_calloc(handle->cfg.desc_num, sizeof(uint8_t *), DAC_DMA_ALLOC_CAPS);
ESP_RETURN_ON_FALSE(handle->bufs, ESP_ERR_NO_MEM, TAG, "failed to allocate dma buffer array");
lldesc_t *descs = (lldesc_t *)heap_caps_calloc(handle->cfg.desc_num, sizeof(lldesc_t), DAC_DMA_ALLOC_CAPS);
ESP_RETURN_ON_FALSE(descs, ESP_ERR_NO_MEM, TAG, "failed to allocate dma descriptors");
for (int cnt = 0; cnt < handle->cfg.desc_num; cnt++) {
/* Allocate DMA descriptor */
handle->desc[cnt] = &descs[cnt];
ESP_GOTO_ON_FALSE(handle->desc[cnt], ESP_ERR_NO_MEM, err, TAG, "failed to allocate dma descriptor");
ESP_LOGD(TAG, "desc[%d] %p", cnt, handle->desc[cnt]);
/* Allocate DMA buffer */
handle->bufs[cnt] = (uint8_t *) heap_caps_calloc(1, handle->cfg.buf_size, DAC_DMA_ALLOC_CAPS);
ESP_GOTO_ON_FALSE(handle->bufs[cnt], ESP_ERR_NO_MEM, err, TAG, "failed to allocate dma buffer");
/* Assign initial value */
lldesc_config(handle->desc[cnt], LLDESC_SW_OWNED, 1, 0, handle->cfg.buf_size);
handle->desc[cnt]->size = handle->cfg.buf_size;
handle->desc[cnt]->buf = handle->bufs[cnt];
handle->desc[cnt]->offset = 0;
}
return ESP_OK;
err:
/* Free DMA buffer if failed to allocate memory */
s_dac_free_dma_desc(handle);
return ret;
}
static void IRAM_ATTR s_dac_default_intr_handler(void *arg)
{
dac_continuous_handle_t handle = (dac_continuous_handle_t)arg;
uint32_t dummy;
BaseType_t need_awoke = pdFALSE;
BaseType_t tmp = pdFALSE;
uint32_t intr_mask = dac_dma_periph_intr_is_triggered();
if (intr_mask & DAC_DMA_EOF_INTR) {
lldesc_t *fdesc = (lldesc_t *)dac_dma_periph_intr_get_eof_desc();
if (!atomic_load(&handle->is_cyclic)) {
/* Remove the descriptor in the chain that finished sent */
DESC_ENTER_CRITICAL_ISR();
if (STAILQ_FIRST(&handle->head) != NULL) {
DAC_STAILQ_REMOVE(&handle->head, fdesc, lldesc_s, qe);
}
DESC_EXIT_CRITICAL_ISR();
if (xQueueIsQueueFullFromISR(handle->desc_pool) == pdTRUE) {
xQueueReceiveFromISR(handle->desc_pool, &dummy, &tmp);
need_awoke |= tmp;
}
xQueueSendFromISR(handle->desc_pool, &fdesc, &tmp);
need_awoke |= tmp;
}
if (handle->cbs.on_convert_done) {
dac_event_data_t evt_data = {
.buf = (void *)fdesc->buf,
.buf_size = handle->cfg.buf_size,
.write_bytes = fdesc->length,
};
need_awoke |= handle->cbs.on_convert_done(handle, &evt_data, handle->user_data);
}
}
if (intr_mask & DAC_DMA_TEOF_INTR) {
/* Total end of frame interrupt received, DMA stopped */
atomic_store(&handle->is_running, false);
if (handle->cbs.on_stop) {
need_awoke |= handle->cbs.on_stop(handle, NULL, handle->user_data);
}
}
if (need_awoke == pdTRUE) {
portYIELD_FROM_ISR();
}
}
esp_err_t dac_continuous_new_channels(const dac_continuous_config_t *cont_cfg, dac_continuous_handle_t *ret_handle)
{
#if CONFIG_DAC_ENABLE_DEBUG_LOG
esp_log_level_set(TAG, ESP_LOG_DEBUG);
#endif
/* Parameters validation */
DAC_NULL_POINTER_CHECK(cont_cfg);
DAC_NULL_POINTER_CHECK(ret_handle);
ESP_RETURN_ON_FALSE(cont_cfg->chan_mask <= DAC_CHANNEL_MASK_ALL, ESP_ERR_INVALID_ARG, TAG, "invalid dac channel id");
ESP_RETURN_ON_FALSE(cont_cfg->desc_num > 1, ESP_ERR_INVALID_STATE, TAG, "at least two DMA descriptor needed");
ESP_RETURN_ON_FALSE(!s_dma_in_use, ESP_ERR_INVALID_STATE, TAG, "DMA already in use");
esp_err_t ret = ESP_OK;
/* Register the channels */
for (uint32_t i = 0, mask = cont_cfg->chan_mask; mask; mask >>= 1, i++) {
if (mask & 0x01) {
ESP_GOTO_ON_ERROR(dac_priv_register_channel(i, "dac continuous"),
err4, TAG, "register dac channel %"PRIu32" failed", i);
}
}
/* Allocate continuous mode struct */
dac_continuous_handle_t handle = heap_caps_calloc(1, sizeof(struct dac_continuous_s), DAC_MEM_ALLOC_CAPS);
ESP_RETURN_ON_FALSE(handle, ESP_ERR_NO_MEM, TAG, "no memory for the dac continuous mode structure");
/* Allocate queue and mutex*/
handle->desc_pool = xQueueCreateWithCaps(cont_cfg->desc_num, sizeof(lldesc_t *), DAC_MEM_ALLOC_CAPS);
handle->mutex = xSemaphoreCreateMutexWithCaps(DAC_MEM_ALLOC_CAPS);
ESP_GOTO_ON_FALSE(handle->desc_pool, ESP_ERR_NO_MEM, err3, TAG, "no memory for message queue");
ESP_GOTO_ON_FALSE(handle->mutex, ESP_ERR_NO_MEM, err3, TAG, "no memory for channels mutex");
/* Create PM lock */
#if CONFIG_PM_ENABLE
esp_pm_lock_type_t pm_lock_type = cont_cfg->clk_src == DAC_DIGI_CLK_SRC_APLL ? ESP_PM_NO_LIGHT_SLEEP : ESP_PM_APB_FREQ_MAX;
ESP_GOTO_ON_ERROR(esp_pm_lock_create(pm_lock_type, 0, "dac_driver", &handle->pm_lock), err3, TAG, "Failed to create DAC pm lock");
#endif
handle->chan_cnt = __builtin_popcount(cont_cfg->chan_mask);
memcpy(&(handle->cfg), cont_cfg, sizeof(dac_continuous_config_t));
atomic_init(&handle->is_enabled, false);
atomic_init(&handle->is_cyclic, false);
atomic_init(&handle->is_running, false);
atomic_init(&handle->is_async, false);
/* Allocate DMA buffer */
ESP_GOTO_ON_ERROR(s_dac_alloc_dma_desc(handle), err2, TAG, "Failed to allocate memory for DMA buffers");
/* Initialize DAC DMA peripheral */
ESP_GOTO_ON_ERROR(dac_dma_periph_init(cont_cfg->freq_hz,
cont_cfg->chan_mode == DAC_CHANNEL_MODE_ALTER,
cont_cfg->clk_src == DAC_DIGI_CLK_SRC_APLL),
err2, TAG, "Failed to initialize DAC DMA peripheral");
/* Register DMA interrupt */
ESP_GOTO_ON_ERROR(esp_intr_alloc(dac_dma_periph_get_intr_signal(), DAC_INTR_ALLOC_FLAGS,
s_dac_default_intr_handler, handle, &(handle->intr_handle)),
err1, TAG, "Failed to register DAC DMA interrupt");
/* Connect DAC module to the DMA peripheral */
DAC_RTC_ENTER_CRITICAL();
dac_ll_digi_enable_dma(true);
DAC_RTC_EXIT_CRITICAL();
s_dma_in_use = true;
*ret_handle = handle;
return ret;
err1:
dac_dma_periph_deinit();
err2:
s_dac_free_dma_desc(handle);
err3:
if (handle->desc_pool) {
vQueueDeleteWithCaps(handle->desc_pool);
}
if (handle->mutex) {
vSemaphoreDeleteWithCaps(handle->mutex);
}
free(handle);
err4:
/* Deregister the channels */
for (uint32_t i = 0, mask = cont_cfg->chan_mask; mask; mask >>= 1, i++) {
if (mask & 0x01) {
dac_priv_deregister_channel(i);
}
}
return ret;
}
esp_err_t dac_continuous_del_channels(dac_continuous_handle_t handle)
{
DAC_NULL_POINTER_CHECK(handle);
ESP_RETURN_ON_FALSE(!atomic_load(&handle->is_enabled), ESP_ERR_INVALID_STATE, TAG, "dac continuous output not disabled yet");
/* Deregister DMA interrupt */
if (handle->intr_handle) {
ESP_RETURN_ON_ERROR(esp_intr_free(handle->intr_handle), TAG, "Failed to deregister DMA interrupt");
handle->intr_handle = NULL;
}
/* Deinitialize DMA peripheral */
ESP_RETURN_ON_ERROR(dac_dma_periph_deinit(), TAG, "Failed to deinitialize DAC DMA peripheral");
/* Disconnect DAC module from the DMA peripheral */
DAC_RTC_ENTER_CRITICAL();
dac_ll_digi_enable_dma(false);
DAC_RTC_EXIT_CRITICAL();
/* Free allocated resources */
s_dac_free_dma_desc(handle);
if (handle->desc_pool) {
vQueueDeleteWithCaps(handle->desc_pool);
handle->desc_pool = NULL;
}
if (handle->mutex) {
vSemaphoreDeleteWithCaps(handle->mutex);
handle->mutex = NULL;
}
#if CONFIG_PM_ENABLE
if (handle->pm_lock) {
esp_pm_lock_delete(handle->pm_lock);
handle->pm_lock = NULL;
}
#endif
/* Deregister the channels */
for (uint32_t i = 0, mask = handle->cfg.chan_mask; mask; mask >>= 1, i++) {
if (mask & 0x01) {
dac_priv_deregister_channel(i);
}
}
free(handle);
s_dma_in_use = false;
return ESP_OK;
}
esp_err_t dac_continuous_register_event_callback(dac_continuous_handle_t handle, const dac_event_callbacks_t *callbacks, void *user_data)
{
DAC_NULL_POINTER_CHECK(handle);
if (!callbacks) {
memset(&handle->cbs, 0, sizeof(dac_event_callbacks_t));
return ESP_OK;
}
#if CONFIG_DAC_ISR_IRAM_SAFE
if (callbacks->on_convert_done) {
ESP_RETURN_ON_FALSE(esp_ptr_in_iram(callbacks->on_convert_done), ESP_ERR_INVALID_ARG, TAG, "on_convert_done callback not in IRAM");
}
if (callbacks->on_stop) {
ESP_RETURN_ON_FALSE(esp_ptr_in_iram(callbacks->on_stop), ESP_ERR_INVALID_ARG, TAG, "on_stop callback not in IRAM");
}
if (user_data) {
ESP_RETURN_ON_FALSE(esp_ptr_internal(user_data), ESP_ERR_INVALID_ARG, TAG, "user context not in internal RAM");
}
#endif
memcpy(&handle->cbs, callbacks, sizeof(dac_event_callbacks_t));
handle->user_data = user_data;
return ESP_OK;
}
esp_err_t dac_continuous_enable(dac_continuous_handle_t handle)
{
DAC_NULL_POINTER_CHECK(handle);
ESP_RETURN_ON_FALSE(!atomic_load(&handle->is_enabled), ESP_ERR_INVALID_STATE, TAG, "dac continuous has already enabled");
esp_err_t ret = ESP_OK;
/* Reset the descriptor pool */
xQueueReset(handle->desc_pool);
for (int i = 0; i < handle->cfg.desc_num; i++) {
ESP_GOTO_ON_FALSE(xQueueSend(handle->desc_pool, &handle->desc[i], 0) == pdTRUE,
ESP_ERR_INVALID_STATE, err, TAG, "the descriptor pool is not cleared");
}
#ifdef CONFIG_PM_ENABLE
esp_pm_lock_acquire(handle->pm_lock);
#endif
for (uint32_t i = 0, mask = handle->cfg.chan_mask; mask; mask >>= 1, i++) {
if (mask & 0x01) {
dac_priv_enable_channel(i);
}
}
dac_dma_periph_enable();
esp_intr_enable(handle->intr_handle);
DAC_RTC_ENTER_CRITICAL();
dac_ll_digi_enable_dma(true);
DAC_RTC_EXIT_CRITICAL();
atomic_store(&handle->is_enabled, true);
err:
return ret;
}
esp_err_t dac_continuous_disable(dac_continuous_handle_t handle)
{
DAC_NULL_POINTER_CHECK(handle);
ESP_RETURN_ON_FALSE(atomic_load(&handle->is_enabled), ESP_ERR_INVALID_STATE, TAG, "dac continuous has already disabled");
atomic_store(&handle->is_enabled, false);
dac_dma_periph_disable();
esp_intr_disable(handle->intr_handle);
DAC_RTC_ENTER_CRITICAL();
dac_ll_digi_enable_dma(false);
DAC_RTC_EXIT_CRITICAL();
atomic_store(&handle->is_running, false);
for (uint32_t i = 0, mask = handle->cfg.chan_mask; mask; mask >>= 1, i++) {
if (mask & 0x01) {
dac_priv_disable_channel(i);
}
}
#ifdef CONFIG_PM_ENABLE
esp_pm_lock_release(handle->pm_lock);
#endif
return ESP_OK;
}
esp_err_t dac_continuous_start_async_writing(dac_continuous_handle_t handle)
{
DAC_NULL_POINTER_CHECK(handle);
ESP_RETURN_ON_FALSE(atomic_load(&handle->is_enabled), ESP_ERR_INVALID_STATE, TAG, "dac continuous has not been enabled");
ESP_RETURN_ON_FALSE(handle->cbs.on_convert_done, ESP_ERR_INVALID_STATE, TAG,
"please register 'on_convert_done' callback before starting asynchronous writing");
atomic_store(&handle->is_async, true);
if (atomic_load(&handle->is_cyclic)) {
/* Break the DMA descriptor chain to stop the DMA first */
for (int i = 0; i < handle->cfg.desc_num; i++) {
STAILQ_NEXT(handle->desc[i], qe) = NULL;
}
}
/* Wait for the previous DMA stop */
while (atomic_load(&handle->is_running)) {}
/* Link all descriptors as a ring */
for (int i = 0; i < handle->cfg.desc_num; i++) {
memset(handle->bufs[i], 0, handle->cfg.buf_size);
STAILQ_NEXT(handle->desc[i], qe) = (i < handle->cfg.desc_num - 1) ? handle->desc[i + 1] : handle->desc[0];
}
dac_dma_periph_dma_trans_start((uint32_t)handle->desc[0]);
atomic_store(&handle->is_running, true);
return ESP_OK;
}
esp_err_t dac_continuous_stop_async_writing(dac_continuous_handle_t handle)
{
DAC_NULL_POINTER_CHECK(handle);
ESP_RETURN_ON_FALSE(atomic_load(&handle->is_async), ESP_ERR_INVALID_STATE, TAG, "dac asynchronous writing has not been started");
/* Break the DMA descriptor chain to stop the DMA first */
for (int i = 0; i < handle->cfg.desc_num; i++) {
STAILQ_NEXT(handle->desc[i], qe) = NULL;
}
/* Wait for the previous DMA stop */
while (atomic_load(&handle->is_running)) {}
atomic_store(&handle->is_async, false);
return ESP_OK;
}
/* Buffer expanding coefficient, the input buffer will expand to twice length while enabled AUTO_16_BIT */
#if CONFIG_DAC_DMA_AUTO_16BIT_ALIGN
#define DAC_16BIT_ALIGN_COEFF 2
#else
#define DAC_16BIT_ALIGN_COEFF 1
#endif
static size_t s_dac_load_data_into_buf(dac_continuous_handle_t handle, uint8_t *dest, size_t dest_len, const uint8_t *src, size_t src_len)
{
size_t load_bytes = 0;
#if CONFIG_DAC_DMA_AUTO_16BIT_ALIGN
/* Load the data to the high 8 bit in the 16-bit width slot */
load_bytes = (src_len * 2 > dest_len) ? dest_len : src_len * 2;
for (int i = 0; i < load_bytes; i += 2) {
dest[i + 1] = src[i / 2] + handle->cfg.offset;
}
#else
/* Load the data into the DMA buffer */
load_bytes = (src_len > dest_len) ? dest_len : src_len;
for (int i = 0; i < load_bytes; i++) {
dest[i] = src[i] + handle->cfg.offset;
}
#endif
return load_bytes;
}
esp_err_t dac_continuous_write_asynchronously(dac_continuous_handle_t handle, uint8_t *dma_buf,
size_t dma_buf_len, const uint8_t *data,
size_t data_len, size_t *bytes_loaded)
{
DAC_NULL_POINTER_CHECK_ISR(handle);
DAC_NULL_POINTER_CHECK_ISR(dma_buf);
DAC_NULL_POINTER_CHECK_ISR(data);
ESP_RETURN_ON_FALSE_ISR(atomic_load(&handle->is_async), ESP_ERR_INVALID_STATE, TAG, "The asynchronous writing has not started");
int i;
for (i = 0; i < handle->cfg.desc_num; i++) {
if (dma_buf == handle->bufs[i]) {
break;
}
}
/* Fail to find the DMA buffer address */
ESP_RETURN_ON_FALSE_ISR(i < handle->cfg.desc_num, ESP_ERR_NOT_FOUND, TAG, "Not found the corresponding DMA buffer");
size_t load_bytes = s_dac_load_data_into_buf(handle, dma_buf, dma_buf_len, data, data_len);
lldesc_config(handle->desc[i], LLDESC_HW_OWNED, 1, 0, load_bytes);
if (bytes_loaded) {
*bytes_loaded = load_bytes / DAC_16BIT_ALIGN_COEFF;
}
return ESP_OK;
}
esp_err_t dac_continuous_write_cyclically(dac_continuous_handle_t handle, uint8_t *buf, size_t buf_size, size_t *bytes_loaded)
{
DAC_NULL_POINTER_CHECK(handle);
ESP_RETURN_ON_FALSE(atomic_load(&handle->is_enabled), ESP_ERR_INVALID_STATE, TAG, "This set of DAC channels has not been enabled");
ESP_RETURN_ON_FALSE(!atomic_load(&handle->is_async), ESP_ERR_INVALID_STATE, TAG, "Asynchronous writing is running, can't write cyclically");
ESP_RETURN_ON_FALSE(buf_size <= handle->cfg.buf_size * handle->cfg.desc_num, ESP_ERR_INVALID_ARG, TAG,
"The cyclic buffer size exceeds the total DMA buffer size: %"PRIu32"(desc_num) * %d(buf_size) = %"PRIu32,
handle->cfg.desc_num, handle->cfg.buf_size, handle->cfg.buf_size * handle->cfg.desc_num);
esp_err_t ret = ESP_OK;
xSemaphoreTake(handle->mutex, portMAX_DELAY);
if (atomic_load(&handle->is_cyclic)) {
/* Break the DMA descriptor chain to stop the DMA first */
for (int i = 0; i < handle->cfg.desc_num; i++) {
STAILQ_NEXT(handle->desc[i], qe) = NULL;
}
}
/* Wait for the previous DMA stop */
while (atomic_load(&handle->is_running)) {}
atomic_store(&handle->is_cyclic, true);
size_t src_buf_size = buf_size;
uint32_t split = 1;
int i;
for (i = 0; i < handle->cfg.desc_num && buf_size > 0; i++) {
/* To spread data more averagely, average the last two descriptors */
split = (buf_size * DAC_16BIT_ALIGN_COEFF < handle->cfg.buf_size * 2) ? 3 - split : 1;
size_t load_bytes = s_dac_load_data_into_buf(handle, handle->bufs[i], handle->cfg.buf_size, buf, buf_size / split);
lldesc_config(handle->desc[i], LLDESC_HW_OWNED, 1, 0, load_bytes);
/* Link to the next descriptor */
STAILQ_NEXT(handle->desc[i], qe) = (i < handle->cfg.desc_num - 1) ? handle->desc[i + 1] : NULL;
buf_size -= load_bytes / DAC_16BIT_ALIGN_COEFF;
buf += load_bytes / DAC_16BIT_ALIGN_COEFF;
}
/* Link the tail to the head as a ring */
STAILQ_NEXT(handle->desc[i - 1], qe) = handle->desc[0];
dac_dma_periph_dma_trans_start((uint32_t)handle->desc[0]);
atomic_store(&handle->is_running, true);
if (bytes_loaded) {
*bytes_loaded = src_buf_size - buf_size;
}
xSemaphoreGive(handle->mutex);
return ret;
}
static esp_err_t s_dac_wait_to_load_dma_data(dac_continuous_handle_t handle, uint8_t *buf, size_t buf_size, size_t *w_size, TickType_t timeout_tick)
{
lldesc_t *desc;
/* Try to get the descriptor from the pool */
ESP_RETURN_ON_FALSE(xQueueReceive(handle->desc_pool, &desc, timeout_tick) == pdTRUE,
ESP_ERR_TIMEOUT, TAG, "Get available descriptor timeout");
/* To ensure it is not in the pending desc chain */
if (STAILQ_FIRST(&handle->head) != NULL) {
DAC_STAILQ_REMOVE(&handle->head, desc, lldesc_s, qe);
}
static bool split_flag = false;
uint8_t *dma_buf = (uint8_t *)desc->buf;
if (buf_size * DAC_16BIT_ALIGN_COEFF < 2 * handle->cfg.buf_size) {
if (!split_flag) {
buf_size >>= 1;
split_flag = true;
} else {
split_flag = false;
}
}
size_t load_bytes = s_dac_load_data_into_buf(handle, dma_buf, handle->cfg.buf_size, buf, buf_size);
lldesc_config(desc, LLDESC_HW_OWNED, 1, 0, load_bytes);
desc->size = load_bytes;
*w_size = load_bytes / DAC_16BIT_ALIGN_COEFF;
/* Insert the loaded descriptor to the end of the chain, waiting to be sent */
DESC_ENTER_CRITICAL();
STAILQ_INSERT_TAIL(&handle->head, desc, qe);
DESC_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t dac_continuous_write(dac_continuous_handle_t handle, uint8_t *buf, size_t buf_size, size_t *bytes_loaded, int timeout_ms)
{
DAC_NULL_POINTER_CHECK(handle);
DAC_NULL_POINTER_CHECK(buf);
ESP_RETURN_ON_FALSE(atomic_load(&handle->is_enabled), ESP_ERR_INVALID_STATE, TAG, "This set of DAC channels has not been enabled");
ESP_RETURN_ON_FALSE(!atomic_load(&handle->is_async), ESP_ERR_INVALID_STATE, TAG, "Asynchronous writing is running, can't write synchronously");
esp_err_t ret = ESP_OK;
TickType_t timeout_tick = timeout_ms < 0 ? portMAX_DELAY : pdMS_TO_TICKS(timeout_ms);
ESP_RETURN_ON_FALSE(xSemaphoreTake(handle->mutex, timeout_tick) == pdTRUE, ESP_ERR_TIMEOUT, TAG, "Take semaphore timeout");
size_t w_size = 0;
size_t src_buf_size = buf_size;
/* Reset the desc_pool and chain if called cyclic function last time */
if (atomic_load(&handle->is_cyclic)) {
xQueueReset(handle->desc_pool);
/* Break the chain if DMA still running */
for (int i = 0; i < handle->cfg.desc_num; i++) {
STAILQ_NEXT(handle->desc[i], qe) = NULL;
xQueueSend(handle->desc_pool, &handle->desc[i], 0);
}
STAILQ_INIT(&handle->head);
atomic_store(&handle->is_cyclic, false);
}
/* When there is no descriptor in the chain, DMA has stopped, load data and start the DMA link */
if (STAILQ_FIRST(&handle->head) == NULL) {
/* Wait for the previous DMA stop */
while (atomic_load(&handle->is_running)) {}
for (int i = 0;
i < handle->cfg.desc_num && buf_size > 0;
i++, buf += w_size, buf_size -= w_size) {
ESP_GOTO_ON_ERROR(s_dac_wait_to_load_dma_data(handle, buf, buf_size, &w_size, timeout_tick), err, TAG, "Load data failed");
}
dac_dma_periph_dma_trans_start((uint32_t)(STAILQ_FIRST(&handle->head)));
atomic_store(&handle->is_running, true);
}
/* If the source buffer is not totally loaded, keep loading the rest data */
while (buf_size > 0) {
ESP_GOTO_ON_ERROR(s_dac_wait_to_load_dma_data(handle, buf, buf_size, &w_size, timeout_tick), err, TAG, "Load data failed");
/* If the DMA stopped but there are still some descriptors not sent, start the DMA again */
DESC_ENTER_CRITICAL();
if (STAILQ_FIRST(&handle->head) && !atomic_load(&handle->is_running)) {
dac_dma_periph_dma_trans_start((uint32_t)(STAILQ_FIRST(&handle->head)));
atomic_store(&handle->is_running, true);
}
DESC_EXIT_CRITICAL();
buf += w_size;
buf_size -= w_size;
}
err:
/* The bytes number that has been loaded */
if (bytes_loaded) {
*bytes_loaded = src_buf_size - buf_size;
}
xSemaphoreGive(handle->mutex);
return ret;
}