[Keyboard] add claw44 keyboard (#5511)

* add claw44 keyboard

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/readme.md

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Remove unnecessary code because of default value

* Move layer definition

* Update keyboards/claw44/keymaps/default/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/keymaps/yfuku/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/readme.md

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* default keymap. LAYOUT_kc -> LAYOUT macro

* Move rules.mk from keymaps to keyboard level.

* add Hardware Supported, Hardware Availability

* Update keyboards/claw44/keymaps/default/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/keymaps/yfuku/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Remove depreciated function

1 files changed, 70 insertions, 0 deletions

diff --git a/keyboards/claw44/rev1/split_util.c b/keyboards/claw44/rev1/split_util.c
new file mode 100644
index 0000000000..e1ff8b4379
--- /dev/null
+++ b/keyboards/claw44/rev1/split_util.c
@@ -0,0 +1,70 @@
+#include <avr/io.h>
+#include <avr/wdt.h>
+#include <avr/power.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include <avr/eeprom.h>
+#include "split_util.h"
+#include "matrix.h"
+#include "keyboard.h"
+
+#ifdef USE_MATRIX_I2C
+#  include "i2c.h"
+#else
+#  include "split_scomm.h"
+#endif
+
+volatile bool isLeftHand = true;
+
+static void setup_handedness(void) {
+  #ifdef EE_HANDS
+    isLeftHand = eeprom_read_byte(EECONFIG_HANDEDNESS);
+  #else
+    // I2C_MASTER_RIGHT is deprecated, use MASTER_RIGHT instead, since this works for both serial and i2c
+    #if defined(I2C_MASTER_RIGHT) || defined(MASTER_RIGHT)
+      isLeftHand = !has_usb();
+    #else
+      isLeftHand = has_usb();
+    #endif
+  #endif
+}
+
+static void keyboard_master_setup(void) {
+
+#ifdef USE_MATRIX_I2C
+    i2c_master_init();
+#else
+    serial_master_init();
+#endif
+}
+
+static void keyboard_slave_setup(void) {
+
+#ifdef USE_MATRIX_I2C
+    i2c_slave_init(SLAVE_I2C_ADDRESS);
+#else
+    serial_slave_init();
+#endif
+}
+
+bool has_usb(void) {
+   USBCON |= (1 << OTGPADE); //enables VBUS pad
+   _delay_us(5);
+   return (USBSTA & (1<<VBUS));  //checks state of VBUS
+}
+
+void split_keyboard_setup(void) {
+   setup_handedness();
+
+   if (has_usb()) {
+      keyboard_master_setup();
+   } else {
+      keyboard_slave_setup();
+   }
+   sei();
+}
+
+// this code runs before the usb and keyboard is initialized
+void matrix_setup(void) {
+    split_keyboard_setup();
+}