Fix T-Deck SD card detection

src/FSCommon.cpp

@@ -23,6 +23,10 @@ SPIClass SPI1(HSPI);
 #define SDHandler SPI
 #endif
 
+#ifndef SD_SPI_FREQUENCY
+#define SD_SPI_FREQUENCY 4000000U
+#endif
+
 #endif // HAS_SDCARD
 
 #if defined(ARCH_STM32WL)
@@ -361,8 +365,7 @@ void setupSDCard()
 #ifdef HAS_SDCARD
     concurrency::LockGuard g(spiLock);
     SDHandler.begin(SPI_SCK, SPI_MISO, SPI_MOSI);
-
-    if (!SD.begin(SDCARD_CS, SDHandler)) {
+    if (!SD.begin(SDCARD_CS, SDHandler, SD_SPI_FREQUENCY)) {
         LOG_DEBUG("No SD_MMC card detected");
         return;
     }

src/main.cpp

@@ -270,6 +270,15 @@ void setup()
     // TF Card , Display backlight(AW9364DNR) , AN48841B(Trackball) , ES7210(Decoder)
     pinMode(KB_POWERON, OUTPUT);
     digitalWrite(KB_POWERON, HIGH);
+    // T-Deck has all three SPI peripherals (TFT, SD, LoRa) attached to the same SPI bus
+    // We need to initialize all CS pins in advance otherwise there will be SPI communication issues
+    // e.g. when detecting the SD card
+    pinMode(LORA_CS, OUTPUT);
+    digitalWrite(LORA_CS, HIGH);
+    pinMode(SDCARD_CS, OUTPUT);
+    digitalWrite(SDCARD_CS, HIGH);
+    pinMode(TFT_CS, OUTPUT);
+    digitalWrite(TFT_CS, HIGH);
     delay(100);
 #endif
 

variants/t-deck/platformio.ini

@@ -43,7 +43,7 @@ build_flags =
   -D HAS_SCREEN=0
   -D HAS_TFT=1
   -D USE_I2S_BUZZER
-  -D RAM_SIZE=2048
+  -D RAM_SIZE=4096
 	-D LV_LVGL_H_INCLUDE_SIMPLE
 	-D LV_CONF_INCLUDE_SIMPLE
 	-D LV_COMP_CONF_INCLUDE_SIMPLE

variants/t-deck/variant.h

@@ -1,8 +1,10 @@
+
+#define TFT_CS 12
 #ifndef HAS_TFT // for TFT-UI the definitions are in device-ui
 #define BUTTON_PIN 0
 
 // ST7789 TFT LCD
-#define ST7789_CS 12
+#define ST7789_CS TFT_CS
 #define ST7789_RS 11  // DC
 #define ST7789_SDA 41 // MOSI
 #define ST7789_SCK 40
@@ -46,6 +48,7 @@
 #define SPI_MISO (38)
 #define SPI_CS (39)
 #define SDCARD_CS SPI_CS
+#define SD_SPI_FREQUENCY 75000000U
 
 #define BATTERY_PIN 4 // A battery voltage measurement pin, voltage divider connected here to measure battery voltage
 // ratio of voltage divider = 2.0 (RD2=100k, RD3=100k)