SDIO doesn't take a clock speed parameter (earlephilhower#2766)

It's fixed by the PIO program and GPIO slew rates encoded in the SdFAT
driver.  Remove the parameter from the SD/SDFS begins.

Author: earlephilhower

libraries/SD/src/SD.h

@@ -42,8 +42,8 @@ class SDClass {
         return SDFS.begin();
     }
 
-    bool begin(uint8_t clkPin, uint8_t cmdPin, uint8_t dat0Pin, uint32_t cfg = SD_SCK_MHZ(50)) {
-        SDFS.setConfig(SDFSConfig(clkPin, cmdPin, dat0Pin, cfg));
+    bool begin(uint8_t clkPin, uint8_t cmdPin, uint8_t dat0Pin) {
+        SDFS.setConfig(SDFSConfig(clkPin, cmdPin, dat0Pin));
         return SDFS.begin();
     }
 

libraries/SDFS/src/SDFS.h

@@ -46,7 +46,7 @@ class SDFSConfig : public FSConfig {
     static constexpr uint32_t FSId = 0x53444653;
 
     SDFSConfig(uint8_t csPin = 4, uint32_t spi = SD_SCK_MHZ(10), HardwareSPI &port = SPI) : FSConfig(FSId, false), _sdio(false), _clkPin(255), _csPin(csPin), _cmdPin(255), _dat0Pin(255), _part(0), _spiSettings(spi), _spi(&port)  { }
-    SDFSConfig(uint8_t clkPin, uint8_t cmdPin, uint8_t dataPin, uint32_t spi = SD_SCK_MHZ(10)) : FSConfig(FSId, false), _sdio(true), _clkPin(clkPin), _cmdPin(cmdPin), _dat0Pin(dataPin), _part(0), _spiSettings(spi), _spi(nullptr)  { }
+    SDFSConfig(uint8_t clkPin, uint8_t cmdPin, uint8_t dataPin) : FSConfig(FSId, false), _sdio(true), _clkPin(clkPin), _cmdPin(cmdPin), _dat0Pin(dataPin), _part(0), _spiSettings(SD_SCK_MHZ(1)), _spi(nullptr)  { }
 
     SDFSConfig setAutoFormat(bool val = true) {
         _autoFormat = val;