Merge branch 'feature/use_circular_dma_desc_link_in_adc_continuous_mo…

…de' into 'master'

adc: pr 11500, use circular dma descriptors in adc continuous mode

Closes IDFGH-10235

See merge request espressif/esp-idf!24048

components/driver/deprecated/adc_dma_legacy.c

@@ -386,11 +386,6 @@ static IRAM_ATTR bool s_adc_dma_intr(adc_digi_context_t *adc_digi_ctx)
         }
     }
 
-    if (status == ADC_HAL_DMA_DESC_NULL) {
-        //start next turns of dma operation
-        adc_hal_digi_start(&adc_digi_ctx->hal, adc_digi_ctx->rx_dma_buf);
-    }
-
     return (taskAwoken == pdTRUE);
 }
 

components/esp_adc/adc_continuous.c

@@ -263,6 +263,7 @@ static IRAM_ATTR bool adc_dma_in_suc_eof_callback(gdma_channel_handle_t dma_chan
     ctx->rx_eof_desc_addr = event_data->rx_eof_desc_addr;
     return s_adc_dma_intr(user_data);
 }
+
 #else
 static IRAM_ATTR void adc_dma_intr_handler(void *arg)
 {
@@ -342,11 +343,6 @@ static IRAM_ATTR bool s_adc_dma_intr(adc_continuous_ctx_t *adc_digi_ctx)
         }
     }
 
-    if (status == ADC_HAL_DMA_DESC_NULL) {
-        //start next turns of dma operation
-        adc_hal_digi_start(&adc_digi_ctx->hal, adc_digi_ctx->rx_dma_buf);
-    }
-
     return need_yield;
 }
 

components/hal/adc_hal.c

@@ -234,6 +234,7 @@ static void adc_hal_digi_dma_link_descriptors(dma_descriptor_t *desc, uint8_t *d
     HAL_ASSERT(((uint32_t)data_buf % 4) == 0);
     HAL_ASSERT((per_eof_size % 4) == 0);
     uint32_t n = 0;
+    dma_descriptor_t *desc_head = desc;
 
     while (eof_num--) {
         uint32_t eof_size = per_eof_size;
@@ -257,7 +258,7 @@ static void adc_hal_digi_dma_link_descriptors(dma_descriptor_t *desc, uint8_t *d
             n++;
         }
     }
-    desc[n-1].next = NULL;
+    desc[n-1].next = desc_head;
 }
 
 void adc_hal_digi_start(adc_hal_dma_ctx_t *hal, uint8_t *data_buf)
@@ -312,15 +313,24 @@ adc_hal_dma_desc_status_t adc_hal_get_reading_result(adc_hal_dma_ctx_t *hal, con
 
     //Find the eof list start
     eof_desc = eof_desc->next;
+    eof_desc->dw0.owner = 1;
     buffer_start = eof_desc->buffer;
     eof_len += eof_desc->dw0.length;
+    if ((intptr_t)eof_desc == eof_desc_addr) {
+        goto valid;
+    }
 
     //Find the eof list end
     for (int i = 1; i < hal->eof_step; i++) {
         eof_desc = eof_desc->next;
+        eof_desc->dw0.owner = 1;
         eof_len += eof_desc->dw0.length;
+        if ((intptr_t)eof_desc == eof_desc_addr) {
+            goto valid;
+        }
     }
 
+valid:
     hal->cur_desc_ptr = eof_desc;
     *buffer = buffer_start;
     *len = eof_len;