added defines for sorting types, removed unused variables

Firmware/Configuration_adv.h

@@ -253,6 +253,10 @@
 // In current firmware Prusa Firmware version,
 // SDSORT_CACHE_NAMES and SDSORT_DYNAMIC_RAM is not supported and must be set to false.
 #ifdef SDCARD_SORT_ALPHA
+  #define SD_SORT_TIME 0
+  #define SD_SORT_ALPHA 1
+  #define SD_SORT_NONE 2
+
   #define SDSORT_LIMIT       40    // Maximum number of sorted items (10-256).
   #define FOLDER_SORTING     -1     // -1=above  0=none  1=below
   #define SDSORT_GCODE       false  // Allow turning sorting on/off with LCD and M34 g-code.

Firmware/Marlin.h

@@ -92,12 +92,6 @@ extern const char echomagic[] PROGMEM;
 
 #define SERIAL_ECHOPAIR(name,value) (serial_echopair_P(PSTR(name),(value)))
 
-typedef enum {
-	SDSORT_TIME,
-	SDSORT_ALPHA,
-	SDSORT_NONE
-} sdsort;
-
 void serial_echopair_P(const char *s_P, float v);
 void serial_echopair_P(const char *s_P, double v);
 void serial_echopair_P(const char *s_P, unsigned long v);

Firmware/cardreader.cpp

@@ -708,7 +708,7 @@ void CardReader::presort() {
 	
 	uint8_t sdSort = eeprom_read_byte((uint8_t*)EEPROM_SD_SORT);
 	
-	if (sdSort == 2) return; //sd sort is turned off
+	if (sdSort == SD_SORT_NONE) return; //sd sort is turned off
 	#if !SDSORT_USES_RAM
 	  lcd_set_progress();
 	#endif
@@ -870,9 +870,9 @@ void CardReader::presort() {
 					// Sort the current pair according to settings.
 					if(
 						#if HAS_FOLDER_SORTING
-	  					  (sdSort == 0 && _SORT_CMP_TIME_DIR(FOLDER_SORTING)) || (sdSort == 1 && _SORT_CMP_DIR(FOLDER_SORTING))
+	  					  (sdSort == SD_SORT_TIME && _SORT_CMP_TIME_DIR(FOLDER_SORTING)) || (sdSort == SD_SORT_ALPHA && _SORT_CMP_DIR(FOLDER_SORTING))
 						#else
-						  (sdSort == 0 && _SORT_CMP_TIME_NODIR()) || (sdSort == 1 && _SORT_CMP_NODIR())
+						  (sdSort == SD_SORT_TIME && _SORT_CMP_TIME_NODIR()) || (sdSort == SD_SORT_ALPHA && _SORT_CMP_NODIR())
 						#endif
 					  )
 					{

Firmware/cardreader.h

@@ -7,7 +7,6 @@
 
 #include "SdFile.h"
 enum LsAction {LS_SerialPrint,LS_Count,LS_GetFilename};
-enum SdSort {sdSortTime, sdSortAlpha, sdSortNone};
 
 class CardReader
 {
@@ -139,7 +138,6 @@ private:
   bool autostart_stilltocheck; //the sd start is delayed, because otherwise the serial cannot answer fast enought to make contact with the hostsoftware.
   
   LsAction lsAction; //stored for recursion.
-  uint8_t sdSort;
   int16_t nrFiles; //counter for the files in the current directory and recycled as position counter for getting the nrFiles'th name in the directory.
   char* diveDirName;
   void lsDive(const char *prepend, SdFile parent, const char * const match=NULL);

Firmware/ultralcd.cpp

@@ -2397,15 +2397,16 @@ void EEPROM_read(int pos, uint8_t* value, uint8_t size)
     value++;
   } while (--size);
 }
+
 #ifdef SDCARD_SORT_ALPHA
 static void lcd_sort_type_set() {
 	uint8_t sdSort;
 	
 	EEPROM_read(EEPROM_SD_SORT, (uint8_t*)&sdSort, sizeof(sdSort));
 	switch (sdSort) {
-	case 0: sdSort = 1; break;
+	case SD_SORT_TIME: sdSort = SD_SORT_ALPHA; break;
-	case 1: sdSort = 2; break;
+	case SD_SORT_ALPHA: sdSort = SD_SORT_NONE; break;
-	default: sdSort = 0;
+	default: sdSort = SD_SORT_TIME;
 	}
 	eeprom_update_byte((unsigned char *)EEPROM_SD_SORT, sdSort);
 	lcd_goto_menu(lcd_sdcard_menu, 1);
@@ -4160,8 +4161,8 @@ void lcd_sdcard_menu()
 #ifdef SDCARD_SORT_ALPHA
   EEPROM_read(EEPROM_SD_SORT, (uint8_t*)&sdSort, sizeof(sdSort));
   switch(sdSort){
-    case 0: MENU_ITEM(function, MSG_SORT_TIME, lcd_sort_type_set); break;
+    case SD_SORT_TIME: MENU_ITEM(function, MSG_SORT_TIME, lcd_sort_type_set); break;
-    case 1: MENU_ITEM(function, MSG_SORT_ALPHA, lcd_sort_type_set); break;
+    case SD_SORT_ALPHA: MENU_ITEM(function, MSG_SORT_ALPHA, lcd_sort_type_set); break;
     default: MENU_ITEM(function, MSG_SORT_NONE, lcd_sort_type_set);
   }
 #endif // SDCARD_SORT_ALPHA
@@ -4179,7 +4180,7 @@ void lcd_sdcard_menu()
   {
     if (_menuItemNr == _lineNr)
     {
-		const uint16_t nr = (sdSort == 2) ? (fileCnt - 1 - i) : i;
+		const uint16_t nr = (sdSort == SD_SORT_NONE) ? (fileCnt - 1 - i) : i;
 		 /* #ifdef SDCARD_RATHERRECENTFIRST
 			#ifndef SDCARD_SORT_ALPHA
 				fileCnt - 1 -
@@ -4187,7 +4188,7 @@ void lcd_sdcard_menu()
 		  #endif
 		i;*/
 		#ifdef SDCARD_SORT_ALPHA
-		if (sdSort == 2) card.getfilename(nr);
+		if (sdSort == SD_SORT_NONE) card.getfilename(nr);
 		else card.getfilename_sorted(nr);
 		#else
 		  card.getfilename(nr);