add lcd image icon rendering

main/lcd_reg.c

@@ -3,6 +3,7 @@
 #include "driver/gpio.h"
 #include "driver/spi_master.h"
 #include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
 #include "freertos/task.h"
 
 #define LCD_SPI_HOST SPI2_HOST
@@ -25,12 +26,60 @@
 #define LCD_CMD_DISPON 0x29
 
 static spi_device_handle_t lcd_spi;
+static SemaphoreHandle_t lcd_mutex;
 
-static void lcd_delay_ms(uint32_t ms)
+/* Timing */
+
+void lcd_delay_ms(uint32_t ms)
 {
     vTaskDelay(pdMS_TO_TICKS(ms));
 }
 
+/* Low-level bus and command helpers */
+
+static void lcd_spi_write(const void *data, uint32_t length)
+{
+    spi_transaction_t transaction = {
+        .length = length * 8,
+        .tx_buffer = data,
+    };
+
+    spi_device_polling_transmit(lcd_spi, &transaction);
+}
+
+static void lcd_write(uint8_t dc_level, uint16_t value, uint8_t length)
+{
+    uint8_t bytes[2] = {
+        (uint8_t)(value >> 8),
+        (uint8_t)value,
+    };
+    const uint8_t *data = length == 1 ? &bytes[1] : bytes;
+
+    gpio_set_level(LCD_PIN_DC, dc_level);
+    lcd_spi_write(data, length);
+}
+
+void lcd_set_window(uint16_t x0, uint16_t y0, uint16_t x1, uint16_t y1)
+{
+    lcd_write(0, LCD_CMD_CASET, 1);
+    lcd_write(1, x0, 2);
+    lcd_write(1, x1, 2);
+
+    lcd_write(0, LCD_CMD_RASET, 1);
+    lcd_write(1, y0, 2);
+    lcd_write(1, y1, 2);
+
+    lcd_write(0, LCD_CMD_RAMWR, 1);
+}
+
+void lcd_write_pixels(const void *data, uint32_t length)
+{
+    gpio_set_level(LCD_PIN_DC, 1);
+    lcd_spi_write(data, length);
+}
+
+/* Initialization */
+
 static void lcd_gpio_init(void)
 {
     gpio_config_t gpio_config_data = {
@@ -80,96 +129,32 @@ static void lcd_reset(void)
     lcd_delay_ms(120);
 }
 
-static void lcd_spi_write(const void *data, uint32_t length)
+static void lcd_controller_init(void)
 {
-    spi_transaction_t transaction = {
-        .length = length * 8,
-        .tx_buffer = data,
-    };
+    lcd_write(0, LCD_CMD_SWRESET, 1);
+    lcd_delay_ms(150);
 
-    spi_device_polling_transmit(lcd_spi, &transaction);
-}
+    lcd_write(0, LCD_CMD_SLPOUT, 1);
+    lcd_delay_ms(120);
 
-static void lcd_write_command(uint8_t command)
-{
-    gpio_set_level(LCD_PIN_DC, 0);
-    lcd_spi_write(&command, 1);
-}
+    lcd_write(0, LCD_CMD_COLMOD, 1);
+    lcd_write(1, 0x05, 1);
 
-static void lcd_write_data8(uint8_t data)
-{
-    gpio_set_level(LCD_PIN_DC, 1);
-    lcd_spi_write(&data, 1);
-}
+    lcd_write(0, LCD_CMD_MADCTL, 1);
+    lcd_write(1, 0x60, 1);
 
-static void lcd_write_data16(uint16_t data)
-{
-    uint8_t bytes[2] = {
-        (uint8_t)(data >> 8),
-        (uint8_t)data,
-    };
+    lcd_write(0, LCD_CMD_INVON, 1);
 
-    gpio_set_level(LCD_PIN_DC, 1);
-    lcd_spi_write(bytes, sizeof(bytes));
-}
-
-static void lcd_set_window(uint16_t x0, uint16_t y0, uint16_t x1, uint16_t y1)
-{
-    lcd_write_command(LCD_CMD_CASET);
-    lcd_write_data16(x0);
-    lcd_write_data16(x1);
-
-    lcd_write_command(LCD_CMD_RASET);
-    lcd_write_data16(y0);
-    lcd_write_data16(y1);
-
-    lcd_write_command(LCD_CMD_RAMWR);
+    lcd_write(0, LCD_CMD_DISPON, 1);
+    lcd_delay_ms(120);
 }
 
 void lcd_reg_init(void)
 {
+    lcd_mutex = xSemaphoreCreateMutex();
+
     lcd_gpio_init();
     lcd_spi_init();
     lcd_reset();
-
-    lcd_write_command(LCD_CMD_SWRESET);
-    lcd_delay_ms(150);
-
-    lcd_write_command(LCD_CMD_SLPOUT);
-    lcd_delay_ms(120);
-
-    lcd_write_command(LCD_CMD_COLMOD);
-    lcd_write_data8(0x05);
-
-    lcd_write_command(LCD_CMD_MADCTL);
-    lcd_write_data8(0x60);
-
-    lcd_write_command(LCD_CMD_INVON);
-
-    lcd_write_command(LCD_CMD_DISPON);
-    lcd_delay_ms(120);
-}
-
-void lcd_reg_draw_image(const uint16_t *image)
-{
-    enum { LINES_PER_TRANSFER = 20 };
-    static uint16_t line_buffer[LCD_WIDTH * LINES_PER_TRANSFER];
-
-    lcd_set_window(0, 0, LCD_WIDTH - 1, LCD_HEIGHT - 1);
-    gpio_set_level(LCD_PIN_DC, 1);
-
-    for (uint32_t y = 0; y < LCD_HEIGHT; y += LINES_PER_TRANSFER) {
-        uint32_t lines = LINES_PER_TRANSFER;
-        if ((y + lines) > LCD_HEIGHT) {
-            lines = LCD_HEIGHT - y;
-        }
-
-        uint32_t pixels = LCD_WIDTH * lines;
-        for (uint32_t i = 0; i < pixels; i++) {
-            uint16_t color = image[(y * LCD_WIDTH) + i];
-            line_buffer[i] = (uint16_t)((color >> 8) | (color << 8));
-        }
-
-        lcd_spi_write(line_buffer, pixels * 2);
-    }
+    lcd_controller_init();
 }