diff --git a/demos/STM32/RT-STM32F767ZI-NUCLEO144/mcuconf.h b/demos/STM32/RT-STM32F767ZI-NUCLEO144/mcuconf.h
index fd9272b39..de50e1bcb 100644
--- a/demos/STM32/RT-STM32F767ZI-NUCLEO144/mcuconf.h
+++ b/demos/STM32/RT-STM32F767ZI-NUCLEO144/mcuconf.h
@@ -190,13 +190,13 @@
 #define STM32_I2C_USE_I2C4                  FALSE
 #define STM32_I2C_BUSY_TIMEOUT              50
 #define STM32_I2C_I2C1_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 0)
-#define STM32_I2C_I2C1_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 6)
+#define STM32_I2C_I2C1_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 7)
 #define STM32_I2C_I2C2_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 2)
 #define STM32_I2C_I2C2_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 7)
 #define STM32_I2C_I2C3_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 2)
 #define STM32_I2C_I2C3_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 4)
 #define STM32_I2C_I2C4_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 2)
-#define STM32_I2C_I2C4_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 5)
+#define STM32_I2C_I2C4_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 6)
 #define STM32_I2C_I2C1_IRQ_PRIORITY         5
 #define STM32_I2C_I2C2_IRQ_PRIORITY         5
 #define STM32_I2C_I2C3_IRQ_PRIORITY         5
diff --git a/demos/STM32/RT-STM32F769I-DISCOVERY/mcuconf.h b/demos/STM32/RT-STM32F769I-DISCOVERY/mcuconf.h
index 10436986d..5428aadc6 100644
--- a/demos/STM32/RT-STM32F769I-DISCOVERY/mcuconf.h
+++ b/demos/STM32/RT-STM32F769I-DISCOVERY/mcuconf.h
@@ -190,13 +190,13 @@
 #define STM32_I2C_USE_I2C4                  FALSE
 #define STM32_I2C_BUSY_TIMEOUT              50
 #define STM32_I2C_I2C1_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 0)
-#define STM32_I2C_I2C1_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 6)
+#define STM32_I2C_I2C1_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 7)
 #define STM32_I2C_I2C2_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 2)
 #define STM32_I2C_I2C2_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 7)
 #define STM32_I2C_I2C3_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 2)
 #define STM32_I2C_I2C3_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 4)
 #define STM32_I2C_I2C4_RX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 2)
-#define STM32_I2C_I2C4_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 5)
+#define STM32_I2C_I2C4_TX_DMA_STREAM        STM32_DMA_STREAM_ID(1, 6)
 #define STM32_I2C_I2C1_IRQ_PRIORITY         5
 #define STM32_I2C_I2C2_IRQ_PRIORITY         5
 #define STM32_I2C_I2C3_IRQ_PRIORITY         5
diff --git a/os/hal/ports/STM32/STM32F7xx/stm32_registry.h b/os/hal/ports/STM32/STM32F7xx/stm32_registry.h
index 6da55e7e8..124a57f92 100644
--- a/os/hal/ports/STM32/STM32F7xx/stm32_registry.h
+++ b/os/hal/ports/STM32/STM32F7xx/stm32_registry.h
@@ -1163,7 +1163,7 @@
 #define STM32_I2C3_ERROR_NUMBER             73
 #define STM32_I2C3_RX_DMA_MSK               (STM32_DMA_STREAM_ID_MSK(1, 1) |\
                                              STM32_DMA_STREAM_ID_MSK(1, 2))
-#define STM32_I2C3_RX_DMA_CHN               0x00000300
+#define STM32_I2C3_RX_DMA_CHN               0x00000310
 #define STM32_I2C3_TX_DMA_MSK               (STM32_DMA_STREAM_ID_MSK(1, 0) |\
                                              STM32_DMA_STREAM_ID_MSK(1, 4))
 #define STM32_I2C3_TX_DMA_CHN               0x00030008
@@ -1173,8 +1173,10 @@
 #define STM32_I2C4_ERROR_HANDLER            Vector1C0
 #define STM32_I2C4_EVENT_NUMBER             95
 #define STM32_I2C4_ERROR_NUMBER             96
-#define STM32_I2C4_RX_DMA_MSK               STM32_DMA_STREAM_ID_MSK(1, 1)
-#define STM32_I2C4_RX_DMA_CHN               0x00000080
+#define STM32_I2C4_RX_DMA_MSK               (STM32_DMA_STREAM_ID_MSK(1, 5) |\
+                                             STM32_DMA_STREAM_ID_MSK(1, 2) |\
+                                             STM32_DMA_STREAM_ID_MSK(1, 1))
+#define STM32_I2C4_RX_DMA_CHN               0x00200280
 #define STM32_I2C4_TX_DMA_MSK               STM32_DMA_STREAM_ID_MSK(1, 6)
 #define STM32_I2C4_TX_DMA_CHN               0x08000000
 
diff --git a/readme.txt b/readme.txt
index f2da15a50..76bfa1b73 100644
--- a/readme.txt
+++ b/readme.txt
@@ -167,6 +167,8 @@
        dependencies and configuration directories. This makes possible
        to have multiple non-conflicting makefiles in the same project.
        Updated the various platform.mk implementing "smart build" mode.
+- HAL: Fixed wrong DMA settings for STM32F76x I2C3 and I2C4 (bug #920)
+       (backported to 18.2.1 and 17.6.4).
 - LIB: Fixed heap allocator failing on simulators (bug #917)(backported
        to 17.6.4).
 - STP: Fixed CRT0_FORCE_MSP_INIT flag not defaulted in crt0_v7m.S (bug #916)