esp32/ttgo_lora_esp32: Add support to SSD1306 OLED display

boards/xtensa/esp32/common/src/Make.defs

@@ -58,6 +58,10 @@ ifeq ($(CONFIG_LCD_ILI9341),y)
   CSRCS += esp32_ili9341.c
 endif
 
+ifeq ($(CONFIG_LCD_SSD1306_I2C),y)
+  CSRCS += esp32_ssd1306.c
+endif
+
 DEPPATH += --dep-path src
 VPATH += :src
 CFLAGS += $(shell $(INCDIR) "$(CC)" $(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src$(DELIM)board$(DELIM)src)

boards/xtensa/esp32/common/src/esp32_ssd1306.c

@@ -0,0 +1,151 @@
+/****************************************************************************
+ * boards/xtensa/esp32/common/src/esp32_ssd1306.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.
+ *
+ ****************************************************************************/
+
+/* SSD1306 OLED over I2C */
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <debug.h>
+
+#include <nuttx/board.h>
+#include <nuttx/lcd/lcd.h>
+#include <nuttx/lcd/ssd1306.h>
+#include <nuttx/i2c/i2c_master.h>
+
+#if defined(CONFIG_VIDEO_FB) && defined(CONFIG_LCD_FRAMEBUFFER)
+#  include <nuttx/video/fb.h>
+#endif
+
+#include "esp32_gpio.h"
+#include "esp32_i2c.h"
+#include "hardware/esp32_gpio_sigmap.h"
+
+#include "ttgo_lora_esp32.h"
+
+#ifdef HAVE_SSD1306
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define OLED_I2C_PORT         0 /* OLED display connected to I2C0 */
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static FAR struct lcd_dev_s    *g_lcddev;
+
+/* Configuration ************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_lcd_initialize
+ ****************************************************************************/
+
+int board_lcd_initialize(void)
+{
+  FAR struct i2c_master_s *i2c;
+  const int busno = OLED_I2C_PORT;
+  const int devno = 0;
+  int ret = OK;
+
+  /* Configure the OLED GPIOs. This initial configuration is RESET low,
+   * putting the OLED into reset state.
+   */
+
+  esp32_gpio_matrix_out(GPIO_SSD1306_RST, SIG_GPIO_OUT_IDX, 0, 0);
+  esp32_configgpio(GPIO_SSD1306_RST, OUTPUT_FUNCTION_3 | INPUT_FUNCTION_3);
+  esp32_gpiowrite(GPIO_SSD1306_RST, 0);
+
+  /* Wait a bit then release the OLED from the reset state */
+
+  up_mdelay(20);
+  esp32_gpiowrite(GPIO_SSD1306_RST, 1);
+
+  /* Initialize I2C */
+
+  i2c = esp32_i2cbus_initialize(busno);
+  if (!i2c)
+    {
+      lcderr("ERROR: Failed to initialize I2C%d\n", busno);
+      return -ENODEV;
+    }
+
+  /* Bind the I2C port to the OLED */
+
+  g_lcddev = ssd1306_initialize(i2c, NULL, devno);
+  if (!g_lcddev)
+    {
+      lcderr("ERROR: Failed to bind I2C%d to OLED %d\n", busno, devno);
+      return -ENODEV;
+    }
+
+  lcdinfo("Bound I2C0 to OLED %d\n", devno);
+
+  /* And turn the OLED on */
+
+  g_lcddev->setpower(g_lcddev, CONFIG_LCD_MAXPOWER);
+
+#if defined(CONFIG_VIDEO_FB) && defined(CONFIG_LCD_FRAMEBUFFER)
+
+  /* Initialize and register the simulated framebuffer driver */
+
+  ret = fb_register(0, 0);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: fb_register() failed: %d\n", ret);
+      return -ENODEV;
+    }
+#endif
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name:  board_lcd_getdev
+ ****************************************************************************/
+
+FAR struct lcd_dev_s *board_lcd_getdev(int lcddev)
+{
+  if (lcddev == 0)
+    {
+      return g_lcddev;
+    }
+
+  return NULL;
+}
+
+/****************************************************************************
+ * Name:  board_lcd_uninitialize
+ ****************************************************************************/
+
+void board_lcd_uninitialize(void)
+{
+}
+
+#endif /* HAVE_SSD1306 */

boards/xtensa/esp32/ttgo_lora_esp32/src/ttgo_lora_esp32.h

@@ -35,6 +35,17 @@
 
 /* TTGO-LoRa-SX1276-ESP32 GPIOs *********************************************/
 
+/* OLED SSD1306 */
+
+#define HAVE_SSD1306 1
+
+#if !defined(CONFIG_ESP32_I2C) || !defined(CONFIG_ESP32_I2C0) || \
+    !defined(CONFIG_LCD_SSD1306_I2C)
+#  undef HAVE_SSD1306
+#endif
+
+#define GPIO_SSD1306_RST 16
+
 /* BOOT Button */
 
 #define BUTTON_BOOT  0