Update ESP-IDF da2116f + esp32-camera f8f26ab + BLE b232e7f (#2194)

* ESP-IDF da2116f + esp32-camera f8f26ab +BLE b232e7f

* Fix fail compilation due to missing cpp guard

cores/esp32/Esp.cpp

@@ -26,9 +26,9 @@
 #include <soc/soc.h>
 #include <soc/efuse_reg.h>
 #include <esp_partition.h>
-#include <esp_ota_ops.h>
 extern "C" {
-#include <esp_image_format.h>
+#include "esp_ota_ops.h"
+#include "esp_image_format.h"
 }
 #include <MD5Builder.h>
 

platform.txt

@@ -22,7 +22,7 @@ compiler.warning_flags.all=-Wall -Werror=all -Wextra
 
 compiler.path={runtime.tools.xtensa-esp32-elf-gcc.path}/bin/
 compiler.sdk.path={runtime.platform.path}/tools/sdk
-compiler.cpreprocessor.flags=-DESP_PLATFORM -DMBEDTLS_CONFIG_FILE="mbedtls/esp_config.h" -DHAVE_CONFIG_H "-I{compiler.sdk.path}/include/config" "-I{compiler.sdk.path}/include/app_trace" "-I{compiler.sdk.path}/include/app_update" "-I{compiler.sdk.path}/include/asio" "-I{compiler.sdk.path}/include/bootloader_support" "-I{compiler.sdk.path}/include/bt" "-I{compiler.sdk.path}/include/coap" "-I{compiler.sdk.path}/include/console" "-I{compiler.sdk.path}/include/driver" "-I{compiler.sdk.path}/include/esp-tls" "-I{compiler.sdk.path}/include/esp32" "-I{compiler.sdk.path}/include/esp_adc_cal" "-I{compiler.sdk.path}/include/esp_event" "-I{compiler.sdk.path}/include/esp_http_client" "-I{compiler.sdk.path}/include/esp_http_server" "-I{compiler.sdk.path}/include/esp_https_ota" "-I{compiler.sdk.path}/include/esp_https_server" "-I{compiler.sdk.path}/include/esp_ringbuf" "-I{compiler.sdk.path}/include/ethernet" "-I{compiler.sdk.path}/include/expat" "-I{compiler.sdk.path}/include/fatfs" "-I{compiler.sdk.path}/include/freemodbus" "-I{compiler.sdk.path}/include/freertos" "-I{compiler.sdk.path}/include/heap" "-I{compiler.sdk.path}/include/idf_test" "-I{compiler.sdk.path}/include/jsmn" "-I{compiler.sdk.path}/include/json" "-I{compiler.sdk.path}/include/libsodium" "-I{compiler.sdk.path}/include/log" "-I{compiler.sdk.path}/include/lwip" "-I{compiler.sdk.path}/include/mbedtls" "-I{compiler.sdk.path}/include/mdns" "-I{compiler.sdk.path}/include/micro-ecc" "-I{compiler.sdk.path}/include/mqtt" "-I{compiler.sdk.path}/include/newlib" "-I{compiler.sdk.path}/include/nghttp" "-I{compiler.sdk.path}/include/nvs_flash" "-I{compiler.sdk.path}/include/openssl" "-I{compiler.sdk.path}/include/protobuf-c" "-I{compiler.sdk.path}/include/protocomm" "-I{compiler.sdk.path}/include/pthread" "-I{compiler.sdk.path}/include/sdmmc" "-I{compiler.sdk.path}/include/smartconfig_ack" "-I{compiler.sdk.path}/include/soc" "-I{compiler.sdk.path}/include/spi_flash" "-I{compiler.sdk.path}/include/spiffs" "-I{compiler.sdk.path}/include/tcp_transport" "-I{compiler.sdk.path}/include/tcpip_adapter" "-I{compiler.sdk.path}/include/ulp" "-I{compiler.sdk.path}/include/unity" "-I{compiler.sdk.path}/include/vfs" "-I{compiler.sdk.path}/include/wear_levelling" "-I{compiler.sdk.path}/include/wifi_provisioning" "-I{compiler.sdk.path}/include/wpa_supplicant" "-I{compiler.sdk.path}/include/xtensa-debug-module"
+compiler.cpreprocessor.flags=-DESP_PLATFORM -DMBEDTLS_CONFIG_FILE="mbedtls/esp_config.h" -DHAVE_CONFIG_H "-I{compiler.sdk.path}/include/config" "-I{compiler.sdk.path}/include/app_trace" "-I{compiler.sdk.path}/include/app_update" "-I{compiler.sdk.path}/include/asio" "-I{compiler.sdk.path}/include/bootloader_support" "-I{compiler.sdk.path}/include/bt" "-I{compiler.sdk.path}/include/coap" "-I{compiler.sdk.path}/include/console" "-I{compiler.sdk.path}/include/driver" "-I{compiler.sdk.path}/include/esp-tls" "-I{compiler.sdk.path}/include/esp32" "-I{compiler.sdk.path}/include/esp_adc_cal" "-I{compiler.sdk.path}/include/esp_event" "-I{compiler.sdk.path}/include/esp_http_client" "-I{compiler.sdk.path}/include/esp_http_server" "-I{compiler.sdk.path}/include/esp_https_ota" "-I{compiler.sdk.path}/include/esp_https_server" "-I{compiler.sdk.path}/include/esp_ringbuf" "-I{compiler.sdk.path}/include/ethernet" "-I{compiler.sdk.path}/include/expat" "-I{compiler.sdk.path}/include/fatfs" "-I{compiler.sdk.path}/include/freemodbus" "-I{compiler.sdk.path}/include/freertos" "-I{compiler.sdk.path}/include/heap" "-I{compiler.sdk.path}/include/idf_test" "-I{compiler.sdk.path}/include/jsmn" "-I{compiler.sdk.path}/include/json" "-I{compiler.sdk.path}/include/libsodium" "-I{compiler.sdk.path}/include/log" "-I{compiler.sdk.path}/include/lwip" "-I{compiler.sdk.path}/include/mbedtls" "-I{compiler.sdk.path}/include/mdns" "-I{compiler.sdk.path}/include/micro-ecc" "-I{compiler.sdk.path}/include/mqtt" "-I{compiler.sdk.path}/include/newlib" "-I{compiler.sdk.path}/include/nghttp" "-I{compiler.sdk.path}/include/nvs_flash" "-I{compiler.sdk.path}/include/openssl" "-I{compiler.sdk.path}/include/protobuf-c" "-I{compiler.sdk.path}/include/protocomm" "-I{compiler.sdk.path}/include/pthread" "-I{compiler.sdk.path}/include/sdmmc" "-I{compiler.sdk.path}/include/smartconfig_ack" "-I{compiler.sdk.path}/include/soc" "-I{compiler.sdk.path}/include/spi_flash" "-I{compiler.sdk.path}/include/spiffs" "-I{compiler.sdk.path}/include/tcp_transport" "-I{compiler.sdk.path}/include/tcpip_adapter" "-I{compiler.sdk.path}/include/ulp" "-I{compiler.sdk.path}/include/unity" "-I{compiler.sdk.path}/include/vfs" "-I{compiler.sdk.path}/include/wear_levelling" "-I{compiler.sdk.path}/include/wifi_provisioning" "-I{compiler.sdk.path}/include/wpa_supplicant" "-I{compiler.sdk.path}/include/xtensa-debug-module" "-I{compiler.sdk.path}/include/esp32-camera"
 
 compiler.c.cmd=xtensa-esp32-elf-gcc
 compiler.c.flags=-std=gnu99 -Os -g3 -fstack-protector -ffunction-sections -fdata-sections -fstrict-volatile-bitfields -mlongcalls -nostdlib -Wpointer-arith {compiler.warning_flags} -Wno-error=unused-function -Wno-error=unused-but-set-variable -Wno-error=unused-variable -Wno-error=deprecated-declarations -Wno-unused-parameter -Wno-sign-compare -Wno-old-style-declaration -MMD -c
@@ -35,7 +35,7 @@ compiler.S.flags=-c -g3 -x assembler-with-cpp -MMD -mlongcalls
 
 compiler.c.elf.cmd=xtensa-esp32-elf-gcc
 compiler.c.elf.flags=-nostdlib "-L{compiler.sdk.path}/lib" "-L{compiler.sdk.path}/ld" -T esp32_out.ld -T esp32.common.ld -T esp32.rom.ld -T esp32.peripherals.ld -T esp32.rom.spiram_incompatible_fns.ld -u ld_include_panic_highint_hdl -u call_user_start_cpu0 -Wl,--gc-sections -Wl,-static -Wl,--undefined=uxTopUsedPriority  -u __cxa_guard_dummy -u __cxx_fatal_exception
-compiler.c.elf.libs=-lgcc -lopenssl -lbtdm_app -lfatfs -lwps -lcoexist -lwear_levelling -lesp_http_client -lprotobuf-c -lhal -lnewlib -ldriver -lbootloader_support -lpp -lfreemodbus -lmesh -lsmartconfig -ljsmn -lwpa -lethernet -lphy -lapp_trace -lconsole -lulp -lwpa_supplicant -lfreertos -lbt -lmicro-ecc -lcxx -lxtensa-debug-module -ltcp_transport -lmdns -lvfs -lesp_ringbuf -lsoc -lcore -lsdmmc -llibsodium -lcoap -ltcpip_adapter -lprotocomm -lesp_event -lc_nano -lesp-tls -lasio -lrtc -lspi_flash -lwpa2 -lwifi_provisioning -lesp32 -lapp_update -lnghttp -lspiffs -lunity -lesp_https_server -lespnow -lnvs_flash -lesp_adc_cal -llog -lsmartconfig_ack -lexpat -lm -lmqtt -lc -lheap -lmbedtls -llwip -lnet80211 -lesp_http_server -lpthread -ljson -lesp_https_ota  -lstdc++
+compiler.c.elf.libs=-lgcc -lopenssl -lbtdm_app -lfatfs -lwps -lcoexist -lwear_levelling -lesp_http_client -lprotobuf-c -lhal -lnewlib -ldriver -lbootloader_support -lpp -lfreemodbus -lmesh -lsmartconfig -ljsmn -lwpa -lethernet -lphy -lapp_trace -lconsole -lulp -lwpa_supplicant -lfreertos -lbt -lmicro-ecc -lesp32-camera -lcxx -lxtensa-debug-module -ltcp_transport -lmdns -lvfs -lesp_ringbuf -lsoc -lcore -lsdmmc -llibsodium -lcoap -ltcpip_adapter -lprotocomm -lesp_event -lc_nano -lesp-tls -lasio -lrtc -lspi_flash -lwpa2 -lwifi_provisioning -lesp32 -lapp_update -lnghttp -lspiffs -lunity -lesp_https_server -lespnow -lnvs_flash -lesp_adc_cal -llog -lsmartconfig_ack -lexpat -lm -lmqtt -lc -lheap -lmbedtls -llwip -lnet80211 -lesp_http_server -lpthread -ljson -lesp_https_ota  -lstdc++
 
 compiler.as.cmd=xtensa-esp32-elf-as
 

tools/gen_esp32part.py

@@ -35,6 +35,9 @@
 MD5_PARTITION_BEGIN = b"\xEB\xEB" + b"\xFF" * 14 # The first 2 bytes are like magic numbers for MD5 sum
 PARTITION_TABLE_SIZE  = 0x1000  # Size of partition table
 
+MIN_PARTITION_SUBTYPE_APP_OTA = 0x10
+NUM_PARTITION_SUBTYPE_APP_OTA = 16
+
 __version__ = '1.2'
 
 APP_TYPE = 0x00
@@ -254,8 +257,8 @@ class PartitionDefinition(object):
     }
 
     # add subtypes for the 16 OTA slot values ("ota_XX, etc.")
-    for ota_slot in range(16):
-        SUBTYPES[TYPES["app"]]["ota_%d" % ota_slot] = 0x10 + ota_slot
+    for ota_slot in range(NUM_PARTITION_SUBTYPE_APP_OTA):
+        SUBTYPES[TYPES["app"]]["ota_%d" % ota_slot] = MIN_PARTITION_SUBTYPE_APP_OTA + ota_slot
 
     def __init__(self):
         self.name = ""

tools/platformio-build.py

@@ -151,6 +151,7 @@
         join(FRAMEWORK_DIR, "tools", "sdk", "include", "wifi_provisioning"),
         join(FRAMEWORK_DIR, "tools", "sdk", "include", "wpa_supplicant"),
         join(FRAMEWORK_DIR, "tools", "sdk", "include", "xtensa-debug-module"),
+        join(FRAMEWORK_DIR, "tools", "sdk", "include", "esp32-camera"),
         join(FRAMEWORK_DIR, "cores", env.BoardConfig().get("build.core"))
     ],
 
@@ -160,7 +161,7 @@
     ],
 
     LIBS=[
-        "-lgcc", "-lopenssl", "-lbtdm_app", "-lfatfs", "-lwps", "-lcoexist", "-lwear_levelling", "-lesp_http_client", "-lprotobuf-c", "-lhal", "-lnewlib", "-ldriver", "-lbootloader_support", "-lpp", "-lfreemodbus", "-lmesh", "-lsmartconfig", "-ljsmn", "-lwpa", "-lethernet", "-lphy", "-lapp_trace", "-lconsole", "-lulp", "-lwpa_supplicant", "-lfreertos", "-lbt", "-lmicro-ecc", "-lcxx", "-lxtensa-debug-module", "-ltcp_transport", "-lmdns", "-lvfs", "-lesp_ringbuf", "-lsoc", "-lcore", "-lsdmmc", "-llibsodium", "-lcoap", "-ltcpip_adapter", "-lprotocomm", "-lesp_event", "-lc_nano", "-lesp-tls", "-lasio", "-lrtc", "-lspi_flash", "-lwpa2", "-lwifi_provisioning", "-lesp32", "-lapp_update", "-lnghttp", "-lspiffs", "-lunity", "-lesp_https_server", "-lespnow", "-lnvs_flash", "-lesp_adc_cal", "-llog", "-lsmartconfig_ack", "-lexpat", "-lm", "-lmqtt", "-lc", "-lheap", "-lmbedtls", "-llwip", "-lnet80211", "-lesp_http_server", "-lpthread", "-ljson", "-lesp_https_ota", "-lstdc++"
+        "-lgcc", "-lopenssl", "-lbtdm_app", "-lfatfs", "-lwps", "-lcoexist", "-lwear_levelling", "-lesp_http_client", "-lprotobuf-c", "-lhal", "-lnewlib", "-ldriver", "-lbootloader_support", "-lpp", "-lfreemodbus", "-lmesh", "-lsmartconfig", "-ljsmn", "-lwpa", "-lethernet", "-lphy", "-lapp_trace", "-lconsole", "-lulp", "-lwpa_supplicant", "-lfreertos", "-lbt", "-lmicro-ecc", "-lesp32-camera", "-lcxx", "-lxtensa-debug-module", "-ltcp_transport", "-lmdns", "-lvfs", "-lesp_ringbuf", "-lsoc", "-lcore", "-lsdmmc", "-llibsodium", "-lcoap", "-ltcpip_adapter", "-lprotocomm", "-lesp_event", "-lc_nano", "-lesp-tls", "-lasio", "-lrtc", "-lspi_flash", "-lwpa2", "-lwifi_provisioning", "-lesp32", "-lapp_update", "-lnghttp", "-lspiffs", "-lunity", "-lesp_https_server", "-lespnow", "-lnvs_flash", "-lesp_adc_cal", "-llog", "-lsmartconfig_ack", "-lexpat", "-lm", "-lmqtt", "-lc", "-lheap", "-lmbedtls", "-llwip", "-lnet80211", "-lesp_http_server", "-lpthread", "-ljson", "-lesp_https_ota", "-lstdc++"
     ],
 
     LIBSOURCE_DIRS=[

tools/sdk/include/app_update/esp_ota_ops.h

@@ -20,6 +20,7 @@
 #include <stddef.h>
 #include "esp_err.h"
 #include "esp_partition.h"
+#include "esp_image_format.h"
 
 #ifdef __cplusplus
 extern "C"
@@ -41,6 +42,14 @@ extern "C"
  */
 typedef uint32_t esp_ota_handle_t;
 
+/**
+ * @brief   Return esp_app_desc structure. This structure includes app version.
+ * 
+ * Return description for running app.
+ * @return Pointer to esp_app_desc structure.
+ */
+const esp_app_desc_t *esp_ota_get_app_description(void);
+
 /**
  * @brief   Commence an OTA update writing to the specified partition.
 
@@ -170,6 +179,22 @@ const esp_partition_t* esp_ota_get_running_partition(void);
  */
 const esp_partition_t* esp_ota_get_next_update_partition(const esp_partition_t *start_from);
 
+/**
+ * @brief Returns esp_app_desc structure for app partition. This structure includes app version.
+ * 
+ * Returns a description for the requested app partition.
+ * @param[in] partition     Pointer to app partition. (only app partition)
+ * @param[out] app_desc     Structure of info about app.
+ * @return
+ *  - ESP_OK                Successful.
+ *  - ESP_ERR_NOT_FOUND     app_desc structure is not found. Magic word is incorrect.
+ *  - ESP_ERR_NOT_SUPPORTED Partition is not application.
+ *  - ESP_ERR_INVALID_ARG   Arguments is NULL or if partition's offset exceeds partition size.
+ *  - ESP_ERR_INVALID_SIZE  Read would go out of bounds of the partition.
+ *  - or one of error codes from lower-level flash driver.
+ */
+esp_err_t esp_ota_get_partition_description(const esp_partition_t *partition, esp_app_desc_t *app_desc);
+
 #ifdef __cplusplus
 }
 #endif

tools/sdk/include/bootloader_support/bootloader_common.h

@@ -14,6 +14,7 @@
 
 #pragma once
 #include "esp_flash_data_types.h"
+#include "esp_image_format.h"
 
 /// Type of hold a GPIO in low state
 typedef enum {
@@ -23,21 +24,29 @@ typedef enum {
 } esp_comm_gpio_hold_t;
 
 /**
- * @brief Calculate crc for the OTA data partition.
+ * @brief Calculate crc for the OTA data select.
  *
- * @param[in] ota_data The OTA data partition.
+ * @param[in] s The OTA data select.
  * @return    Returns crc value.
  */
 uint32_t bootloader_common_ota_select_crc(const esp_ota_select_entry_t *s);
 
 /**
- * @brief Verifies the validity of the OTA data partition
+ * @brief Verifies the validity of the OTA data select
  *
- * @param[in] ota_data The OTA data partition.
+ * @param[in] s The OTA data select.
  * @return    Returns true on valid, false otherwise.
  */
 bool bootloader_common_ota_select_valid(const esp_ota_select_entry_t *s);
 
+/**
+ * @brief Returns true if OTADATA is not marked as bootable partition.
+ *
+ * @param[in] s The OTA data select.
+ * @return    Returns true if OTADATA invalid, false otherwise.
+ */
+bool bootloader_common_ota_select_invalid(const esp_ota_select_entry_t *s);
+
 /**
  * @brief Check if the GPIO input is a long hold or a short hold.
  *
@@ -91,3 +100,27 @@ bool bootloader_common_label_search(const char *list, char *label);
  *          - ESP_FAIL: An allocation error occurred.
  */
 esp_err_t bootloader_common_get_sha256_of_partition(uint32_t address, uint32_t size, int type, uint8_t *out_sha_256);
+
+/**
+ * @brief Returns the number of active otadata.
+ *
+ * @param[in] two_otadata Pointer on array from two otadata structures.
+ *
+ * @return The number of active otadata (0 or 1).
+ *        - -1: If it does not have active otadata.
+ */
+int bootloader_common_get_active_otadata(esp_ota_select_entry_t *two_otadata);
+
+/**
+ * @brief Returns esp_app_desc structure for app partition. This structure includes app version.
+ * 
+ * Returns a description for the requested app partition.
+ * @param[in] partition      App partition description.
+ * @param[out] app_desc      Structure of info about app.
+ * @return
+ *  - ESP_OK:                Successful.
+ *  - ESP_ERR_INVALID_ARG:   The arguments passed are not valid.
+ *  - ESP_ERR_NOT_FOUND:     app_desc structure is not found. Magic word is incorrect.
+ *  - ESP_FAIL:              mapping is fail.
+ */
+esp_err_t bootloader_common_get_partition_description(const esp_partition_pos_t *partition, esp_app_desc_t *app_desc);

tools/sdk/include/bootloader_support/esp_image_format.h

@@ -89,6 +89,25 @@ typedef struct {
     uint32_t data_len;
 } esp_image_segment_header_t;
 
+#define ESP_APP_DESC_MAGIC_WORD 0xABCD5432 /*!< The magic word for the esp_app_desc structure that is in DROM. */
+
+/**
+ * @brief Description about application.
+ */
+typedef struct {
+    uint32_t magic_word;        /*!< Magic word ESP_APP_DESC_MAGIC_WORD */
+    uint32_t secure_version;    /*!< Secure version */
+    uint32_t reserv1[2];        /*!< --- */
+    char version[32];           /*!< Application version */
+    char project_name[32];      /*!< Project name */
+    char time[16];              /*!< Compile time */
+    char date[16];              /*!< Compile date*/
+    char idf_ver[32];           /*!< Version IDF */
+    uint8_t app_elf_sha256[32]; /*!< sha256 of elf file */
+    uint32_t reserv2[20];       /*!< --- */
+} esp_app_desc_t;
+_Static_assert(sizeof(esp_app_desc_t) == 256, "esp_app_desc_t should be 256 bytes");
+
 #define ESP_IMAGE_MAX_SEGMENTS 16
 
 /* Structure to hold on-flash image metadata */

tools/sdk/include/bt/esp_bt.h

@@ -405,7 +405,6 @@ esp_err_t esp_bt_mem_release(esp_bt_mode_t mode);
  *
  * For ORIG mode:
  * Bluetooth modem sleep is enabled in controller start up by default if CONFIG_BTDM_CONTROLLER_MODEM_SLEEP is set and "ORIG mode" is selected. In ORIG modem sleep mode, bluetooth controller will switch off some components and pause to work every now and then, if there is no event to process; and wakeup according to the scheduled interval and resume the work. It can also wakeup earlier upon external request using function "esp_bt_controller_wakeup_request".
- * Note that currently there is problem in the combination use of bluetooth modem sleep and Dynamic Frequency Scaling(DFS). So do not enable DFS if bluetooth modem sleep is in use.
  *
  * @return
  *                  - ESP_OK : success

tools/sdk/include/config/sdkconfig.h

@@ -63,6 +63,7 @@
 #define CONFIG_MBEDTLS_PEM_WRITE_C 1
 #define CONFIG_BT_SPP_ENABLED 1
 #define CONFIG_BT_RESERVE_DRAM 0xdb5c
+#define CONFIG_APP_COMPILE_TIME_DATE 1
 #define CONFIG_CXX_EXCEPTIONS 1
 #define CONFIG_FATFS_FS_LOCK 0
 #define CONFIG_IP_LOST_TIMER_INTERVAL 120
@@ -76,6 +77,7 @@
 #define CONFIG_SPIRAM_SUPPORT 1
 #define CONFIG_LWIP_MAX_SOCKETS 10
 #define CONFIG_LWIP_NETIF_LOOPBACK 1
+#define CONFIG_ESP32_PTHREAD_TASK_NAME_DEFAULT "pthread"
 #define CONFIG_EMAC_TASK_PRIORITY 20
 #define CONFIG_TIMER_TASK_STACK_DEPTH 2048
 #define CONFIG_TCP_MSS 1436
@@ -201,6 +203,7 @@
 #define CONFIG_MB_QUEUE_LENGTH 20
 #define CONFIG_SW_COEXIST_PREFERENCE_VALUE 0
 #define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_RSA 1
+#define CONFIG_OV2640_SUPPORT 1
 #define CONFIG_FREERTOS_TASK_FUNCTION_WRAPPER 1
 #define CONFIG_MBEDTLS_KEY_EXCHANGE_DHE_PSK 1
 #define CONFIG_PPP_SUPPORT 1
@@ -270,8 +273,10 @@
 #define CONFIG_MBEDTLS_TLS_CLIENT 1
 #define CONFIG_BTDM_CONTROLLER_HCI_MODE_VHCI 1
 #define CONFIG_BT_ENABLED 1
+#define CONFIG_ESP32_DEFAULT_PTHREAD_CORE_NO_AFFINITY 1
 #define CONFIG_MBEDTLS_ECP_DP_SECP256R1_ENABLED 1
 #define CONFIG_MONITOR_BAUD 115200
+#define CONFIG_ESP32_PTHREAD_TASK_CORE_DEFAULT -1
 #define CONFIG_ESP32_DEBUG_STUBS_ENABLE 1
 #define CONFIG_TCPIP_LWIP 1
 #define CONFIG_WIFI_LWIP_ALLOCATION_FROM_SPIRAM_FIRST 1

tools/sdk/include/driver/driver/spi_slave.h

@@ -73,7 +73,10 @@ struct spi_slave_transaction_t {
     size_t length;                  ///< Total data length, in bits
     size_t trans_len;               ///< Transaction data length, in bits
     const void *tx_buffer;          ///< Pointer to transmit buffer, or NULL for no MOSI phase
-    void *rx_buffer;                ///< Pointer to receive buffer, or NULL for no MISO phase
+    void *rx_buffer;                /**< Pointer to receive buffer, or NULL for no MISO phase.
+                                     * When the DMA is anabled, must start at WORD boundary (``rx_buffer%4==0``),
+                                     * and has length of a multiple of 4 bytes.
+                                     */
     void *user;                     ///< User-defined variable. Can be used to store eg transaction ID.
 };