Massdrop keyboard updates for SEND_STRING, syscalls, stdio, debug prints, Auto Shift (#3973)

* Update for SEND_STRING usage

Update for SEND_STRING usage.
Sending keyboard reports (kbd, nkro) now obey the minimum polling time.
While attempting to send a keyboard report and waiting for a USB poll, other functions of the keyboard, including LED effects and power management, will continue to operate at their intended intervals.

* Updates for send string, syscalls, stdio, debug prints, auto shift

Now properly waiting for previous keys sent over USB to complete before sending new.
Added heap to linker and now compiling with syscalls support.
Removed custom string functions and now using stdio.
dprintf now works as intended through virtser device.

* CTRL and ALT keymap updates

CTRL mac keymap updated
ALT default and mac keymap updated
ALT rules.mk added Auto Shift with default no

* Code cleanup as per discussion with vomindoraan

Code cleanup as per discussion with vomindoraan

1 files changed, 15 insertions, 1 deletions

diff --git a/lib/arm_atsam/packs/atmel/SAMD51_DFP/1.0.70/gcc/gcc/samd51j18a_flash.ld b/lib/arm_atsam/packs/atmel/SAMD51_DFP/1.0.70/gcc/gcc/samd51j18a_flash.ld
index 3d114f5b7..35db61971 100644
--- a/lib/arm_atsam/packs/atmel/SAMD51_DFP/1.0.70/gcc/gcc/samd51j18a_flash.ld
+++ b/lib/arm_atsam/packs/atmel/SAMD51_DFP/1.0.70/gcc/gcc/samd51j18a_flash.ld
@@ -35,7 +35,7 @@ SEARCH_DIR(.)
 /* Memory Spaces Definitions */
 MEMORY
 {
-  //rom      (rx)  : ORIGIN = 0x00000000, LENGTH = 0x00040000
+/*rom      (rx)  : ORIGIN = 0x00000000, LENGTH = 0x00040000*/
   rom      (rx)  : ORIGIN = 0x00004000, LENGTH = 0x0003C000
   ram      (rwx) : ORIGIN = 0x20000000, LENGTH = 0x00020000
   bkupram  (rwx) : ORIGIN = 0x47000000, LENGTH = 0x00002000
@@ -45,6 +45,9 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0x8000;
 
+/* The heap size used by the application. */
+HEAP_SIZE = DEFINED(HEAP_SIZE) ? HEAP_SIZE : DEFINED(__heap_size__) ? __heap_size__ : 0x800;
+
 _srom = ORIGIN(rom);
 _lrom = LENGTH(rom);
 _erom = ORIGIN(rom) + LENGTH(rom);
@@ -153,6 +156,17 @@ SECTIONS
         _ezero = .;
     } > ram
 
+    /* .heap section for syscalls */
+    .heap (NOLOAD) :
+    {
+        . = ALIGN(4);
+        _end = .;
+        end = .;
+        _heap_start = .;
+        . = . + HEAP_SIZE;
+        _heap_end = .;
+    } > ram
+
     /* stack section */
     .stack (NOLOAD):
     {