risc-v/esp_<rmt|ws2812>: Implement the RMT peripheral for ESP32 RVs

This commit implements the RMT peripheral for all the supported
Espressif's RISC-V devices. It also implements the support for the
WS2812 addressable RGB LED using the RMT peripheral.

arch/risc-v/src/Makefile

@@ -130,6 +130,7 @@ endif
 
 VPATH += chip
 VPATH += common
+VPATH += common/espressif
 VPATH += $(SBI_DIR)
 VPATH += $(ARCH_SUBDIR)
 VPATH += $(CHIP_DIR)

arch/risc-v/src/common/espressif/Kconfig

@@ -298,6 +298,16 @@ config ESPRESSIF_BROWNOUT_DET
 		than a specific value. If this happens, it will reset the chip in
 		order to prevent unintended behaviour.
 
+config ESP_RMT
+	bool "Remote Control Module (RMT)"
+	default n
+	depends on RMT
+	---help---
+		The RMT (Remote Control Transceiver) peripheral was designed to act as
+		an infrared transceiver. However, due to the flexibility of its data
+		format, RMT can be extended to a versatile and general-purpose
+		transceiver, transmitting or receiving many other types of signals.
+
 endmenu # Peripheral Support
 
 menu "UART Configuration"

arch/risc-v/src/common/espressif/Make.defs

@@ -73,6 +73,13 @@ ifeq ($(CONFIG_ESPRESSIF_USBSERIAL),y)
   CHIP_CSRCS += esp_usbserial.c
 endif
 
+ifeq ($(CONFIG_ESP_RMT),y)
+  CHIP_CSRCS += esp_rmt.c
+  ifeq ($(CONFIG_WS2812_NON_SPI_DRIVER),y)
+    CHIP_CSRCS += esp_ws2812.c
+  endif
+endif
+
 #############################################################################
 # Espressif HAL for 3rd Party Platforms
 #############################################################################

arch/risc-v/src/common/espressif/esp_gpio.h

@@ -98,6 +98,24 @@
 #define ONLOW             0x04
 #define ONHIGH            0x05
 
+/* Check whether it is a valid GPIO number */
+
+#define GPIO_IS_VALID_GPIO(gpio_num)   ((gpio_num >= 0) && \
+                                        (((1ULL << (gpio_num)) & \
+                                         SOC_GPIO_VALID_GPIO_MASK) != 0))
+
+/* Check whether it can be a valid GPIO number of output mode */
+
+#define GPIO_IS_VALID_OUTPUT_GPIO(gpio_num) \
+  ((gpio_num >= 0) && \
+      (((1ULL << (gpio_num)) & SOC_GPIO_VALID_OUTPUT_GPIO_MASK) != 0))
+
+/* Check whether it can be a valid digital I/O pad */
+
+#define GPIO_IS_VALID_DIGITAL_IO_PAD(gpio_num) \
+  ((gpio_num >= 0) && \
+    (((1ULL << (gpio_num)) & SOC_GPIO_VALID_DIGITAL_IO_PAD_MASK) != 0))
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

arch/risc-v/src/common/espressif/esp_rmt.h

@@ -0,0 +1,109 @@
+/****************************************************************************
+ * arch/risc-v/src/common/espressif/esp_rmt.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_RISC_V_SRC_COMMON_ESPRESSIF_ESP_RMT_H
+#define __ARCH_RISC_V_SRC_COMMON_ESPRESSIF_ESP_RMT_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <semaphore.h>
+#include <nuttx/spinlock.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define RMT_MEM_ITEM_NUM SOC_RMT_MEM_WORDS_PER_CHANNEL
+
+#define RMT_DEFAULT_CLK_DIV 1
+
+/* Channel can work during APB clock scaling */
+
+#define RMT_CHANNEL_FLAGS_AWARE_DFS (1 << 0)
+
+/* Invert RMT signal */
+
+#define RMT_CHANNEL_FLAGS_INVERT_SIG (1 << 1)
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/****************************************************************************
+ * Public Functions Prototypes
+ ****************************************************************************/
+
+#if defined(CONFIG_ESP_RMT)
+
+/****************************************************************************
+ * Name: esp_rmt_tx_init
+ *
+ * Description:
+ *   Initialize the selected RMT device in TX mode
+ *
+ * Input Parameters:
+ *   ch   - the RMT's channel that will be used
+ *   pin  - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Valid RMT device structure reference on success; NULL, otherwise.
+ *
+ ****************************************************************************/
+
+struct rmt_dev_s *esp_rmt_tx_init(int ch, int pin);
+
+/****************************************************************************
+ * Name: esp_rmt_rx_init
+ *
+ * Description:
+ *   Initialize the selected RMT device in RC mode
+ *
+ * Input Parameters:
+ *   ch   - the RMT's channel that will be used
+ *   pin  - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Valid RMT device structure reference on success; NULL, otherwise.
+ *
+ ****************************************************************************/
+
+struct rmt_dev_s *esp_rmt_rx_init(int ch, int pin);
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ARCH_RISC_V_SRC_COMMON_ESPRESSIF_ESP_RMT_H */

arch/risc-v/src/common/espressif/esp_ws2812.h

@@ -0,0 +1,100 @@
+/****************************************************************************
+ * arch/risc-v/src/common/espressif/esp_ws2812.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_RISC_V_SRC_COMMON_ESPRESSIF_ESP_WS2812_H
+#define __ARCH_RISC_V_SRC_COMMON_ESPRESSIF_ESP_WS2812_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <debug.h>
+#include <stdbool.h>
+
+#ifndef __ASSEMBLY__
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+#ifdef CONFIG_WS2812
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp_ws2812_setup
+ *
+ * Description:
+ *   This function sets up a WS2812 device instance. It allocates memory for
+ *   the device structures, initializes the device with the provided
+ *   parameters, and registers the device with the system.
+ *
+ * Input Parameters:
+ *   path         - The device path.
+ *   rmt          - Pointer to the RMT device structure.
+ *   pixel_count  - The number of pixels in the WS2812 strip.
+ *   has_white    - Flag indicating if the WS2812 strip includes a white LED.
+ *
+ * Returned Value:
+ *   Returns a pointer to the WS2812 device structure on successful setup;
+ *   NULL is returned on any failure, with errno set appropriately.
+ *
+ ****************************************************************************/
+
+struct ws2812_dev_s *esp_ws2812_setup(const char       *path,
+                                      struct rmt_dev_s *rmt,
+                                      uint16_t         pixel_count,
+                                      bool             has_white);
+/****************************************************************************
+ * Name: esp_ws2812_release
+ *
+ * Description:
+ *   This function releases a previously opened WS2812 device instance. It
+ *   checks if the device is currently open, and if not, it frees the private
+ *   data structure and sets the private field of the device to NULL. If the
+ *   device is still open, it returns an error.
+ *
+ * Input Parameters:
+ *   driver - Pointer to the instance of the WS2812 device driver to be
+ *            released.
+ *
+ * Returned Value:
+ *   Returns OK on successful release of the device; a negated errno value
+ *   is returned on any failure.
+ *
+ ****************************************************************************/
+
+int esp_ws2812_release(void * driver);
+
+#endif
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __ASSEMBLY__ */
+#endif /* __ARCH_RISC_V_SRC_COMMON_ESPRESSIF_ESP_WS2812_H */

arch/risc-v/src/esp32c3/hal_esp32c3.mk

@@ -105,6 +105,7 @@ CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/timer_hal_iram.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/cache_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/mpu_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/mmu_hal.c
+CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/rmt_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/uart_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/uart_hal_iram.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/wdt_hal_iram.c
@@ -115,6 +116,7 @@ CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/log/log_noos.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/riscv/interrupt.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/gpio_periph.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/ledc_periph.c
+CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/rmt_periph.c
 
 ifeq ($(CONFIG_ESPRESSIF_SIMPLE_BOOT),y)
   CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/nuttx/src/bootloader_banner_wrap.c

arch/risc-v/src/esp32c6/hal_esp32c6.mk

@@ -97,6 +97,7 @@ CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/gpio_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/ledc_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/ledc_hal_iram.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/lp_timer_hal.c
+CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/rmt_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/timer_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/timer_hal_iram.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/uart_hal.c
@@ -109,3 +110,4 @@ CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/log/log_noos.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/riscv/interrupt.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/gpio_periph.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/ledc_periph.c
+CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/rmt_periph.c

arch/risc-v/src/esp32h2/hal_esp32h2.mk

@@ -96,6 +96,7 @@ CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/gpio_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/ledc_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/ledc_hal_iram.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/lp_timer_hal.c
+CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/rmt_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/timer_hal.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/timer_hal_iram.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/hal/uart_hal.c
@@ -108,3 +109,4 @@ CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/log/log_noos.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/riscv/interrupt.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/gpio_periph.c
 CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/ledc_periph.c
+CHIP_CSRCS += chip/$(ESP_HAL_3RDPARTY_REPO)/components/soc/$(CHIP_SERIES)/rmt_periph.c

boards/risc-v/esp32c3/common/include/esp_board_rmt.h

@@ -0,0 +1,97 @@
+/****************************************************************************
+ * boards/risc-v/esp32c3/common/include/esp_board_rmt.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_RISC_V_ESP32C3_COMMON_INCLUDE_ESP_BOARD_RMT_H
+#define __BOARDS_RISC_V_ESP32C3_COMMON_INCLUDE_ESP_BOARD_RMT_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef CONFIG_ESP_RMT
+
+/****************************************************************************
+ * Name: board_rmt_rxinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a RX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_rxinitialize(int ch, int pin);
+
+/****************************************************************************
+ * Name: board_rmt_txinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a TX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_txinitialize(int ch, int pin);
+
+#endif /* CONFIG_ESP_RMT */
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __ASSEMBLY__ */
+#endif /* __BOARDS_RISC_V_ESP32C3_COMMON_INCLUDE_ESP_BOARD_RMT_H */

boards/risc-v/esp32c3/common/src/Make.defs

@@ -24,6 +24,10 @@ ifeq ($(CONFIG_ESPRESSIF_LEDC),y)
   CSRCS += esp_board_ledc.c
 endif
 
+ifeq ($(CONFIG_ESP_RMT),y)
+  CSRCS += esp_board_rmt.c
+endif
+
 DEPPATH += --dep-path src
 VPATH += :src
 CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src$(DELIM)board$(DELIM)src

boards/risc-v/esp32c3/common/src/esp_board_rmt.c

@@ -0,0 +1,150 @@
+/****************************************************************************
+ * boards/risc-v/esp32c3/common/src/esp_board_rmt.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <errno.h>
+#include <debug.h>
+#include <stdio.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/rmt/rmtchar.h>
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+#include <nuttx/leds/ws2812.h>
+
+#include "espressif/esp_ws2812.h"
+#endif
+
+#include "espressif/esp_rmt.h"
+
+#ifdef CONFIG_ESP_RMT
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_rmt_rxinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a RX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_rxinitialize(int ch, int pin)
+{
+  int ret;
+
+  struct rmt_dev_s *rmt = esp_rmt_rx_init(ch, pin);
+
+  ret = rmtchar_register(rmt);
+  if (ret < 0)
+    {
+      rmterr("ERROR: rmtchar_register failed: %d\n", ret);
+      return ret;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: board_rmt_txinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a TX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_txinitialize(int ch, int pin)
+{
+  int ret;
+  struct rmt_dev_s *rmt;
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+  struct ws2812_dev_s *led;
+#endif
+
+  rmt = esp_rmt_tx_init(ch, pin);
+  if (rmt == NULL)
+    {
+      rmterr("ERROR: esp_rmt_tx_init failed\n");
+      return -ENODEV;
+    }
+
+  ret = rmtchar_register(rmt);
+  if (ret < 0)
+    {
+      rmterr("ERROR: rmtchar_register failed: %d\n", ret);
+      return ret;
+    }
+
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+  led = esp_ws2812_setup("/dev/leds0", rmt, CONFIG_WS2812_LED_COUNT, false);
+  if (led == NULL)
+    {
+      rmterr("ERROR: esp_ws2812_setup failed\n");
+      return -ENODEV;
+    }
+#endif
+
+  return ret;
+}
+#endif

boards/risc-v/esp32c3/esp32c3-generic/configs/rmt/defconfig

@@ -0,0 +1,59 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_NDEBUG is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+CONFIG_ARCH="risc-v"
+CONFIG_ARCH_BOARD="esp32c3-generic"
+CONFIG_ARCH_BOARD_COMMON=y
+CONFIG_ARCH_BOARD_ESP32C3_GENERIC=y
+CONFIG_ARCH_CHIP="esp32c3"
+CONFIG_ARCH_CHIP_ESP32C3_GENERIC=y
+CONFIG_ARCH_INTERRUPTSTACK=1536
+CONFIG_ARCH_RISCV=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARDCTL_RESET=y
+CONFIG_BOARD_LOOPSPERMSEC=15000
+CONFIG_BUILTIN=y
+CONFIG_DEV_ZERO=y
+CONFIG_ESP_RMT=y
+CONFIG_EXAMPLES_RMTCHAR=y
+CONFIG_EXAMPLES_RMTCHAR_RX=y
+CONFIG_EXAMPLES_RMTCHAR_RX_DEVPATH="/dev/rmt2"
+CONFIG_EXAMPLES_RMTCHAR_TX=y
+CONFIG_EXAMPLES_WS2812=y
+CONFIG_FS_PROCFS=y
+CONFIG_IDLETHREAD_STACKSIZE=2048
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_LIBC_PERROR_STDOUT=y
+CONFIG_LIBC_STRERROR=y
+CONFIG_NFILE_DESCRIPTORS_PER_BLOCK=6
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_READLINE=y
+CONFIG_NSH_STRERROR=y
+CONFIG_PREALLOC_TIMERS=0
+CONFIG_RMT=y
+CONFIG_RMTCHAR=y
+CONFIG_RMT_DEFAULT_RX_BUFFER_SIZE=512
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_BACKTRACE=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_START_DAY=29
+CONFIG_START_MONTH=11
+CONFIG_START_YEAR=2019
+CONFIG_SYSTEM_DUMPSTACK=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TESTING_GETPRIME=y
+CONFIG_TESTING_OSTEST=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_WS2812=y
+CONFIG_WS2812_LED_COUNT=100
+CONFIG_WS2812_NON_SPI_DRIVER=y

boards/risc-v/esp32c3/esp32c3-generic/src/esp32c3-generic.h

@@ -31,6 +31,19 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* RMT gpio */
+
+#define RMT_RXCHANNEL       2
+#define RMT_TXCHANNEL       0
+
+#ifdef CONFIG_RMT_LOOP_TEST_MODE
+#  define RMT_INPUT_PIN     0
+#  define RMT_OUTPUT_PIN    0
+#else
+#  define RMT_INPUT_PIN     2
+#  define RMT_OUTPUT_PIN    8
+#endif
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

boards/risc-v/esp32c3/esp32c3-generic/src/esp32c3_bringup.c

@@ -60,6 +60,10 @@
 #  include <nuttx/input/buttons.h>
 #endif
 
+#ifdef CONFIG_ESP_RMT
+#  include "esp_board_rmt.h"
+#endif
+
 #include "esp32c3-generic.h"
 
 /****************************************************************************
@@ -147,6 +151,20 @@ int esp_bringup(void)
     }
 #endif
 
+#ifdef CONFIG_ESP_RMT
+  ret = board_rmt_txinitialize(RMT_TXCHANNEL, RMT_OUTPUT_PIN);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: board_rmt_txinitialize() failed: %d\n", ret);
+    }
+
+  ret = board_rmt_rxinitialize(RMT_RXCHANNEL, RMT_INPUT_PIN);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: board_rmt_txinitialize() failed: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_RTC_DRIVER
   /* Initialize the RTC driver */
 

boards/risc-v/esp32c6/common/include/esp_board_rmt.h

@@ -0,0 +1,97 @@
+/****************************************************************************
+ * boards/risc-v/esp32c6/common/include/esp_board_rmt.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_RISC_V_ESP32C6_COMMON_INCLUDE_ESP_BOARD_RMT_H
+#define __BOARDS_RISC_V_ESP32C6_COMMON_INCLUDE_ESP_BOARD_RMT_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef CONFIG_ESP_RMT
+
+/****************************************************************************
+ * Name: board_rmt_rxinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a RX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_rxinitialize(int ch, int pin);
+
+/****************************************************************************
+ * Name: board_rmt_txinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a TX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_txinitialize(int ch, int pin);
+
+#endif /* CONFIG_ESP_RMT */
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __ASSEMBLY__ */
+#endif /* __BOARDS_RISC_V_ESP32C6_COMMON_INCLUDE_ESP_BOARD_RMT_H */

boards/risc-v/esp32c6/common/src/Make.defs

@@ -24,6 +24,10 @@ ifeq ($(CONFIG_ESPRESSIF_LEDC),y)
   CSRCS += esp_board_ledc.c
 endif
 
+ifeq ($(CONFIG_ESP_RMT),y)
+  CSRCS += esp_board_rmt.c
+endif
+
 DEPPATH += --dep-path src
 VPATH += :src
 CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src$(DELIM)board$(DELIM)src

boards/risc-v/esp32c6/common/src/esp_board_rmt.c

@@ -0,0 +1,150 @@
+/****************************************************************************
+ * boards/risc-v/esp32c6/common/src/esp_board_rmt.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <errno.h>
+#include <debug.h>
+#include <stdio.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/rmt/rmtchar.h>
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+#include <nuttx/leds/ws2812.h>
+
+#include "espressif/esp_ws2812.h"
+#endif
+
+#include "espressif/esp_rmt.h"
+
+#ifdef CONFIG_ESP_RMT
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_rmt_rxinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a RX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_rxinitialize(int ch, int pin)
+{
+  int ret;
+
+  struct rmt_dev_s *rmt = esp_rmt_rx_init(ch, pin);
+
+  ret = rmtchar_register(rmt);
+  if (ret < 0)
+    {
+      rmterr("ERROR: rmtchar_register failed: %d\n", ret);
+      return ret;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: board_rmt_txinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a TX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_txinitialize(int ch, int pin)
+{
+  int ret;
+  struct rmt_dev_s *rmt;
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+  struct ws2812_dev_s *led;
+#endif
+
+  rmt = esp_rmt_tx_init(ch, pin);
+  if (rmt == NULL)
+    {
+      rmterr("ERROR: esp_rmt_tx_init failed\n");
+      return -ENODEV;
+    }
+
+  ret = rmtchar_register(rmt);
+  if (ret < 0)
+    {
+      rmterr("ERROR: rmtchar_register failed: %d\n", ret);
+      return ret;
+    }
+
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+  led = esp_ws2812_setup("/dev/leds0", rmt, CONFIG_WS2812_LED_COUNT, false);
+  if (led == NULL)
+    {
+      rmterr("ERROR: esp_ws2812_setup failed\n");
+      return -ENODEV;
+    }
+#endif
+
+  return ret;
+}
+#endif

boards/risc-v/esp32c6/esp32c6-devkit/configs/rmt/defconfig

@@ -0,0 +1,59 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+CONFIG_ARCH="risc-v"
+CONFIG_ARCH_BOARD="esp32c6-devkit"
+CONFIG_ARCH_BOARD_COMMON=y
+CONFIG_ARCH_BOARD_ESP32C6_DEVKIT=y
+CONFIG_ARCH_CHIP="esp32c6"
+CONFIG_ARCH_CHIP_ESP32C6=y
+CONFIG_ARCH_INTERRUPTSTACK=2048
+CONFIG_ARCH_RISCV=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARDCTL_RESET=y
+CONFIG_BOARD_LOOPSPERMSEC=15000
+CONFIG_BUILTIN=y
+CONFIG_DEV_ZERO=y
+CONFIG_ESPRESSIF_ESP32C6=y
+CONFIG_ESP_RMT=y
+CONFIG_EXAMPLES_RMTCHAR=y
+CONFIG_EXAMPLES_RMTCHAR_RX=y
+CONFIG_EXAMPLES_RMTCHAR_RX_DEVPATH="/dev/rmt2"
+CONFIG_EXAMPLES_RMTCHAR_TX=y
+CONFIG_EXAMPLES_WS2812=y
+CONFIG_FS_PROCFS=y
+CONFIG_IDLETHREAD_STACKSIZE=2048
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_LIBC_PERROR_STDOUT=y
+CONFIG_LIBC_STRERROR=y
+CONFIG_NFILE_DESCRIPTORS_PER_BLOCK=6
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_READLINE=y
+CONFIG_NSH_STRERROR=y
+CONFIG_PREALLOC_TIMERS=0
+CONFIG_RMT=y
+CONFIG_RMTCHAR=y
+CONFIG_RMT_DEFAULT_RX_BUFFER_SIZE=512
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_BACKTRACE=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_START_DAY=29
+CONFIG_START_MONTH=11
+CONFIG_START_YEAR=2019
+CONFIG_SYSTEM_DUMPSTACK=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TESTING_GETPRIME=y
+CONFIG_TESTING_OSTEST=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_WS2812=y
+CONFIG_WS2812_LED_COUNT=100
+CONFIG_WS2812_NON_SPI_DRIVER=y

boards/risc-v/esp32c6/esp32c6-devkit/src/esp32c6-devkit.h

@@ -31,6 +31,19 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* RMT gpio */
+
+#define RMT_RXCHANNEL       2
+#define RMT_TXCHANNEL       0
+
+#ifdef CONFIG_RMT_LOOP_TEST_MODE
+#  define RMT_INPUT_PIN     0
+#  define RMT_OUTPUT_PIN    0
+#else
+#  define RMT_INPUT_PIN     2
+#  define RMT_OUTPUT_PIN    8
+#endif
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

boards/risc-v/esp32c6/esp32c6-devkit/src/esp32c6_bringup.c

@@ -60,6 +60,10 @@
 #  include <nuttx/input/buttons.h>
 #endif
 
+#ifdef CONFIG_ESP_RMT
+#  include "esp_board_rmt.h"
+#endif
+
 #include "esp32c6-devkit.h"
 
 /****************************************************************************
@@ -147,6 +151,20 @@ int esp_bringup(void)
     }
 #endif
 
+#ifdef CONFIG_ESP_RMT
+  ret = board_rmt_txinitialize(RMT_TXCHANNEL, RMT_OUTPUT_PIN);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: board_rmt_txinitialize() failed: %d\n", ret);
+    }
+
+  ret = board_rmt_rxinitialize(RMT_RXCHANNEL, RMT_INPUT_PIN);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: board_rmt_txinitialize() failed: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_RTC_DRIVER
   /* Initialize the RTC driver */
 

boards/risc-v/esp32h2/common/include/esp_board_rmt.h

@@ -0,0 +1,97 @@
+/****************************************************************************
+ * boards/risc-v/esp32h2/common/include/esp_board_rmt.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_RISC_V_ESP32H2_COMMON_INCLUDE_ESP_BOARD_RMT_H
+#define __BOARDS_RISC_V_ESP32H2_COMMON_INCLUDE_ESP_BOARD_RMT_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef CONFIG_ESP_RMT
+
+/****************************************************************************
+ * Name: board_rmt_rxinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a RX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_rxinitialize(int ch, int pin);
+
+/****************************************************************************
+ * Name: board_rmt_txinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a TX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_txinitialize(int ch, int pin);
+
+#endif /* CONFIG_ESP_RMT */
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __ASSEMBLY__ */
+#endif /* __BOARDS_RISC_V_ESP32H2_COMMON_INCLUDE_ESP_BOARD_RMT_H */

boards/risc-v/esp32h2/common/src/Make.defs

@@ -24,6 +24,10 @@ ifeq ($(CONFIG_ESPRESSIF_LEDC),y)
   CSRCS += esp_board_ledc.c
 endif
 
+ifeq ($(CONFIG_ESP_RMT),y)
+  CSRCS += esp_board_rmt.c
+endif
+
 DEPPATH += --dep-path src
 VPATH += :src
 CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src$(DELIM)board$(DELIM)src

boards/risc-v/esp32h2/common/src/esp_board_rmt.c

@@ -0,0 +1,150 @@
+/****************************************************************************
+ * boards/risc-v/esp32h2/common/src/esp_board_rmt.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <errno.h>
+#include <debug.h>
+#include <stdio.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/rmt/rmtchar.h>
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+#include <nuttx/leds/ws2812.h>
+
+#include "espressif/esp_ws2812.h"
+#endif
+
+#include "espressif/esp_rmt.h"
+
+#ifdef CONFIG_ESP_RMT
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_rmt_rxinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a RX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the RX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_rxinitialize(int ch, int pin)
+{
+  int ret;
+
+  struct rmt_dev_s *rmt = esp_rmt_rx_init(ch, pin);
+
+  ret = rmtchar_register(rmt);
+  if (ret < 0)
+    {
+      rmterr("ERROR: rmtchar_register failed: %d\n", ret);
+      return ret;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: board_rmt_txinitialize
+ *
+ * Description:
+ *   Initialize the RMT peripheral and register a TX device.
+ *
+ * Input Parameters:
+ *   ch  - the RMT's channel that will be used
+ *   pin - The pin used for the TX channel
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int board_rmt_txinitialize(int ch, int pin)
+{
+  int ret;
+  struct rmt_dev_s *rmt;
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+  struct ws2812_dev_s *led;
+#endif
+
+  rmt = esp_rmt_tx_init(ch, pin);
+  if (rmt == NULL)
+    {
+      rmterr("ERROR: esp_rmt_tx_init failed\n");
+      return -ENODEV;
+    }
+
+  ret = rmtchar_register(rmt);
+  if (ret < 0)
+    {
+      rmterr("ERROR: rmtchar_register failed: %d\n", ret);
+      return ret;
+    }
+
+#ifdef CONFIG_WS2812_NON_SPI_DRIVER
+  led = esp_ws2812_setup("/dev/leds0", rmt, CONFIG_WS2812_LED_COUNT, false);
+  if (led == NULL)
+    {
+      rmterr("ERROR: esp_ws2812_setup failed\n");
+      return -ENODEV;
+    }
+#endif
+
+  return ret;
+}
+#endif

boards/risc-v/esp32h2/esp32h2-devkit/configs/rmt/defconfig

@@ -0,0 +1,59 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+CONFIG_ARCH="risc-v"
+CONFIG_ARCH_BOARD="esp32h2-devkit"
+CONFIG_ARCH_BOARD_COMMON=y
+CONFIG_ARCH_BOARD_ESP32H2_DEVKIT=y
+CONFIG_ARCH_CHIP="esp32h2"
+CONFIG_ARCH_CHIP_ESP32H2=y
+CONFIG_ARCH_INTERRUPTSTACK=2048
+CONFIG_ARCH_RISCV=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARDCTL_RESET=y
+CONFIG_BOARD_LOOPSPERMSEC=15000
+CONFIG_BUILTIN=y
+CONFIG_DEV_ZERO=y
+CONFIG_ESPRESSIF_ESP32H2=y
+CONFIG_ESP_RMT=y
+CONFIG_EXAMPLES_RMTCHAR=y
+CONFIG_EXAMPLES_RMTCHAR_RX=y
+CONFIG_EXAMPLES_RMTCHAR_RX_DEVPATH="/dev/rmt2"
+CONFIG_EXAMPLES_RMTCHAR_TX=y
+CONFIG_EXAMPLES_WS2812=y
+CONFIG_FS_PROCFS=y
+CONFIG_IDLETHREAD_STACKSIZE=2048
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_LIBC_PERROR_STDOUT=y
+CONFIG_LIBC_STRERROR=y
+CONFIG_NFILE_DESCRIPTORS_PER_BLOCK=6
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_READLINE=y
+CONFIG_NSH_STRERROR=y
+CONFIG_PREALLOC_TIMERS=0
+CONFIG_RMT=y
+CONFIG_RMTCHAR=y
+CONFIG_RMT_DEFAULT_RX_BUFFER_SIZE=512
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_BACKTRACE=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_START_DAY=29
+CONFIG_START_MONTH=11
+CONFIG_START_YEAR=2019
+CONFIG_SYSTEM_DUMPSTACK=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TESTING_GETPRIME=y
+CONFIG_TESTING_OSTEST=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_WS2812=y
+CONFIG_WS2812_LED_COUNT=100
+CONFIG_WS2812_NON_SPI_DRIVER=y

boards/risc-v/esp32h2/esp32h2-devkit/src/esp32h2-devkit.h

@@ -31,6 +31,19 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* RMT gpio */
+
+#define RMT_RXCHANNEL       2
+#define RMT_TXCHANNEL       0
+
+#ifdef CONFIG_RMT_LOOP_TEST_MODE
+#  define RMT_INPUT_PIN     0
+#  define RMT_OUTPUT_PIN    0
+#else
+#  define RMT_INPUT_PIN     2
+#  define RMT_OUTPUT_PIN    8
+#endif
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

boards/risc-v/esp32h2/esp32h2-devkit/src/esp32h2_bringup.c

@@ -60,6 +60,10 @@
 #  include <nuttx/input/buttons.h>
 #endif
 
+#ifdef CONFIG_ESP_RMT
+#  include "esp_board_rmt.h"
+#endif
+
 #include "esp32h2-devkit.h"
 
 /****************************************************************************
@@ -147,6 +151,20 @@ int esp_bringup(void)
     }
 #endif
 
+#ifdef CONFIG_ESP_RMT
+  ret = board_rmt_txinitialize(RMT_TXCHANNEL, RMT_OUTPUT_PIN);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: board_rmt_txinitialize() failed: %d\n", ret);
+    }
+
+  ret = board_rmt_rxinitialize(RMT_RXCHANNEL, RMT_INPUT_PIN);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: board_rmt_txinitialize() failed: %d\n", ret);
+    }
+#endif
+
 #ifdef CONFIG_RTC_DRIVER
   /* Initialize the RTC driver */