feat(cam): add camera buffer alloc function

Author: Bruce297

components/esp_driver_cam/csi/src/esp_cam_ctlr_csi.c

@@ -51,6 +51,7 @@ static esp_err_t s_ctlr_csi_start(esp_cam_ctlr_handle_t handle);
 static esp_err_t s_ctlr_csi_stop(esp_cam_ctlr_handle_t handle);
 static esp_err_t s_csi_ctlr_disable(esp_cam_ctlr_handle_t ctlr);
 static esp_err_t s_ctlr_csi_receive(esp_cam_ctlr_handle_t handle, esp_cam_ctlr_trans_t *trans, uint32_t timeout_ms);
+static void *s_csi_ctlr_alloc_buffer(esp_cam_ctlr_t *handle, size_t size, uint32_t buf_caps);
 
 static esp_err_t s_csi_claim_controller(csi_controller_t *controller)
 {
@@ -225,6 +226,7 @@ esp_err_t esp_cam_new_csi_ctlr(const esp_cam_ctlr_csi_config_t *config, esp_cam_
     ctlr->base.register_event_callbacks = s_register_event_callbacks;
     ctlr->base.get_internal_buffer = s_csi_ctlr_get_internal_buffer;
     ctlr->base.get_buffer_len = s_csi_ctlr_get_buffer_length;
+    ctlr->base.alloc_buffer = s_csi_ctlr_alloc_buffer;
 
     *ret_handle = &(ctlr->base);
 
@@ -538,3 +540,23 @@ esp_err_t s_ctlr_csi_receive(esp_cam_ctlr_handle_t handle, esp_cam_ctlr_trans_t
 
     return ESP_OK;
 }
+
+static void *s_csi_ctlr_alloc_buffer(esp_cam_ctlr_t *handle, size_t size, uint32_t buf_caps)
+{
+    csi_controller_t *ctlr = __containerof(handle, csi_controller_t, base);
+
+    if (!ctlr) {
+        ESP_LOGE(TAG, "invalid argument: handle is null");
+        return NULL;
+    }
+
+    void *buffer = heap_caps_calloc(1, size, buf_caps);
+    if (!buffer) {
+        ESP_LOGE(TAG, "failed to allocate buffer");
+        return NULL;
+    }
+
+    ESP_LOGD(TAG, "Allocated camera buffer: %p, size: %zu", buffer, size);
+
+    return buffer;
+}

components/esp_driver_cam/dvp/private_include/esp_cam_ctlr_dvp_dma.h

@@ -29,6 +29,8 @@ typedef struct esp_cam_ctlr_dvp_dma {
     esp_cam_ctlr_dvp_dma_desc_t *desc;              /*!< DVP DMA description buffer */
     size_t desc_count;                              /*!< DVP DMA description count */
     size_t desc_size;                               /*!< DVP DMA description buffer size in byte */
+    size_t int_mem_align;                           /*!< DVP DMA internal memory alignment */
+    size_t ext_mem_align;                           /*!< DVP DMA external memory alignment */
 } esp_cam_ctlr_dvp_dma_t;
 
 /**

components/esp_driver_cam/dvp/src/esp_cam_ctlr_dvp_cam.c

@@ -700,6 +700,47 @@ static esp_err_t esp_cam_ctlr_get_dvp_cam_frame_buffer_len(esp_cam_ctlr_handle_t
     return ret;
 }
 
+/**
+ * @brief Allocate aligned camera buffer for ESP CAM DVP controller
+ *
+ * @note This function must be called after esp_cam_new_dvp_ctlr
+ *
+ * @param handle            ESP CAM controller handle
+ * @param size              Buffer size in bytes
+ * @param buf_caps          Buffer allocation capabilities (e.g., MALLOC_CAP_SPIRAM | MALLOC_CAP_DMA)
+ *
+ * @return
+ *        - Buffer pointer on success
+ *        - NULL on failure
+ */
+static void *esp_cam_ctlr_dvp_cam_alloc_buffer(esp_cam_ctlr_t *handle, size_t size, uint32_t buf_caps)
+{
+    esp_cam_ctlr_dvp_cam_t *ctlr = (esp_cam_ctlr_dvp_cam_t *)handle;
+
+    if (!ctlr) {
+        ESP_LOGE(TAG, "invalid argument: handle is null");
+        return NULL;
+    }
+
+    size_t alignment = 1;
+
+    if (buf_caps & MALLOC_CAP_SPIRAM) {
+        alignment = ctlr->dma.ext_mem_align;
+    } else {
+        alignment = ctlr->dma.int_mem_align;
+    }
+
+    void *buffer = heap_caps_aligned_calloc(alignment, 1, size, buf_caps);
+    if (!buffer) {
+        ESP_LOGE(TAG, "failed to allocate buffer");
+        return NULL;
+    }
+
+    ESP_LOGD(TAG, "Allocated aligned camera buffer: %p, size: %zu, alignment: %zu", buffer, size, alignment);
+
+    return buffer;
+}
+
 /**
  * @brief New ESP CAM DVP controller
  *
@@ -793,6 +834,7 @@ esp_err_t esp_cam_new_dvp_ctlr(const esp_cam_ctlr_dvp_config_t *config, esp_cam_
     ctlr->base.register_event_callbacks = esp_cam_ctlr_dvp_cam_register_event_callbacks;
     ctlr->base.get_internal_buffer = esp_cam_ctlr_dvp_cam_get_internal_buffer;
     ctlr->base.get_buffer_len = esp_cam_ctlr_get_dvp_cam_frame_buffer_len;
+    ctlr->base.alloc_buffer = esp_cam_ctlr_dvp_cam_alloc_buffer;
 
     *ret_handle = &ctlr->base;
 

components/esp_driver_cam/dvp/src/esp_cam_ctlr_dvp_gdma.c

@@ -105,9 +105,8 @@ esp_err_t esp_cam_ctlr_dvp_dma_init(esp_cam_ctlr_dvp_dma_t *dma, uint32_t burst_
         .access_ext_mem = true,
     };
     ESP_GOTO_ON_ERROR(gdma_config_transfer(dma->dma_chan, &transfer_config), fail1, TAG, "set trans ability failed");
-    size_t int_mem_align = 0;
-    size_t ext_mem_align = 0;
-    gdma_get_alignment_constraints(dma->dma_chan, &int_mem_align, &ext_mem_align);
+
+    gdma_get_alignment_constraints(dma->dma_chan, &dma->int_mem_align, &dma->ext_mem_align);
 
     dma->desc_count = size / ESP_CAM_CTLR_DVP_DMA_DESC_BUFFER_MAX_SIZE;
     if (size % ESP_CAM_CTLR_DVP_DMA_DESC_BUFFER_MAX_SIZE) {

components/esp_driver_cam/esp_cam_ctlr.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -91,3 +91,11 @@ esp_err_t esp_cam_ctlr_del(esp_cam_ctlr_handle_t handle)
 
     return handle->del(handle);
 }
+
+void *esp_cam_ctlr_alloc_buffer(esp_cam_ctlr_handle_t handle, size_t size, uint32_t buf_caps)
+{
+    ESP_RETURN_ON_FALSE(handle, NULL, TAG, "invalid argument: null pointer");
+    ESP_RETURN_ON_FALSE(handle->alloc_buffer, NULL, TAG, "alloc_buffer function not supported");
+
+    return handle->alloc_buffer(handle, size, buf_caps);
+}

components/esp_driver_cam/include/esp_cam_ctlr.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -9,6 +9,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include "esp_err.h"
+#include "esp_heap_caps.h"
 #include "esp_cam_ctlr_types.h"
 
 #ifdef __cplusplus
@@ -132,6 +133,23 @@ esp_err_t esp_cam_ctlr_get_frame_buffer(esp_cam_ctlr_handle_t handle, uint32_t f
  */
 esp_err_t esp_cam_ctlr_get_frame_buffer_len(esp_cam_ctlr_handle_t handle, size_t *ret_fb_len);
 
+/**
+ * @brief Allocate camera buffer for ESP CAM controller
+ *
+ * @note This function must be called after esp_cam_new_*_ctlr
+ *
+ * @param[in] handle            ESP CAM controller handle
+ * @param[in] size              Buffer size in bytes
+ * @param[in] buf_caps          Buffer allocation capabilities:
+ *                              - MALLOC_CAP_SPIRAM || MALLOC_CAP_DMA: Memory in external SPI RAM
+ *                              - MALLOC_CAP_INTERNAL || MALLOC_CAP_DMA: Memory in internal SRAM
+ *
+ * @return
+ *        - Buffer pointer on success
+ *        - NULL on failure
+ */
+void *esp_cam_ctlr_alloc_buffer(esp_cam_ctlr_handle_t handle, size_t size, uint32_t buf_caps);
+
 #ifdef __cplusplus
 }
 #endif

components/esp_driver_cam/interface/esp_cam_ctlr_interface.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -133,6 +133,19 @@ struct esp_cam_ctlr_t {
      */
     esp_err_t (*get_buffer_len)(esp_cam_ctlr_t *, size_t *);
 
+    /**
+     * @brief Allocate aligned camera buffer for ESP CAM controller
+     *
+     * @param[in]   esp_cam_ctlr_t *    ESP CAM controller handle
+     * @param[in]   size_t              Buffer size in bytes
+     * @param[in]   uint32_t            Buffer allocation capabilities
+     *
+     * @return
+     *        - Buffer pointer on success
+     *        - NULL on failure
+     */
+    void *(*alloc_buffer)(esp_cam_ctlr_t *, size_t, uint32_t);
+
     void *user_data;  ///< User data
 };
 

components/esp_driver_cam/isp_dvp/src/esp_cam_ctlr_isp_dvp.c

@@ -85,6 +85,7 @@ static esp_err_t s_isp_dvp_start(esp_cam_ctlr_handle_t handle);
 static esp_err_t s_isp_dvp_stop(esp_cam_ctlr_handle_t handle);
 static esp_err_t s_isp_dvp_receive(esp_cam_ctlr_handle_t handle, esp_cam_ctlr_trans_t *trans, uint32_t timeout_ms);
 static bool s_dvp_dma_trans_done_callback(dw_gdma_channel_handle_t chan, const dw_gdma_trans_done_event_data_t *event_data, void *user_data);
+static void *s_isp_dvp_alloc_buffer(esp_cam_ctlr_t *handle, size_t size, uint32_t buf_caps);
 
 esp_err_t esp_cam_new_isp_dvp_ctlr(isp_proc_handle_t isp_proc, const esp_cam_ctlr_isp_dvp_cfg_t *ctlr_config, esp_cam_ctlr_handle_t *ret_handle)
 {
@@ -200,6 +201,7 @@ esp_err_t esp_cam_new_isp_dvp_ctlr(isp_proc_handle_t isp_proc, const esp_cam_ctl
     cam_ctlr->register_event_callbacks = s_isp_dvp_register_event_callbacks;
     cam_ctlr->get_internal_buffer = s_isp_dvp_get_frame_buffer;
     cam_ctlr->get_buffer_len = s_isp_dvp_get_frame_buffer_length;
+    cam_ctlr->alloc_buffer = s_isp_dvp_alloc_buffer;
     *ret_handle = cam_ctlr;
 
     return ESP_OK;
@@ -594,3 +596,23 @@ static esp_err_t s_isp_declaim_dvp_controller(isp_dvp_controller_t *dvp_ctlr)
 
     return ESP_OK;
 }
+
+static void *s_isp_dvp_alloc_buffer(esp_cam_ctlr_t *handle, size_t size, uint32_t buf_caps)
+{
+    isp_dvp_controller_t *dvp_ctlr = __containerof(handle, isp_dvp_controller_t, base);
+
+    if (!dvp_ctlr) {
+        ESP_LOGE(TAG, "invalid argument: handle is null");
+        return NULL;
+    }
+
+    void *buffer = heap_caps_calloc(1, size, buf_caps);
+    if (!buffer) {
+        ESP_LOGE(TAG, "failed to allocate buffer");
+        return NULL;
+    }
+
+    ESP_LOGD(TAG, "Allocated camera buffer: %p, size: %zu", buffer, size);
+
+    return buffer;
+}

docs/en/api-reference/peripherals/camera_driver.rst

@@ -112,6 +112,8 @@ Camera controller driver can be implemented in one of following ways:
 
     If :cpp:type:`esp_cam_ctlr_lcd_cam_cfg_t` is specified, users can call :cpp:func:`esp_cam_new_lcd_cam_ctlr` to allocate and initialize a DVP camera controller handle. This function will return an DVP camera controller handle if it runs correctly. You can take following code as reference.
 
+    After calling :cpp:func:`esp_cam_new_dvp_ctlr`, you should allocate a camera buffer that meets the alignment constraints, or call :cpp:func:`esp_cam_ctlr_alloc_buffer` to automatically allocate.
+
     .. code:: c
 
         esp_cam_ctlr_handle_t cam_handle = NULL;

docs/zh_CN/api-reference/peripherals/camera_driver.rst

@@ -112,6 +112,8 @@
 
     如果指定了 :cpp:type:`esp_cam_ctlr_dvp_config_t` 中的配置，就可以调用 :cpp:func:`esp_cam_new_dvp_ctlr` 来分配和初始化 DVP 摄像头控制器句柄。如果函数运行正确，将返回一个 DVP 摄像头控制器句柄。请参考以下代码。
 
+    在调用 :cpp:func:`esp_cam_new_dvp_ctlr` 之后，需要分配符合对齐约束的摄像头缓冲区，或调用 :cpp:func:`esp_cam_ctlr_alloc_buffer` 来自动分配。
+
     .. code:: c
 
         esp_cam_ctlr_handle_t cam_handle = NULL;