Split common (#3429)

* Line ending stuff again

* Added Let's Split Eh? Files and updated #USE_IC2 checks to also include th EH revision (can only be used in I2C)

* Added personal keymap, updated some of the EH files

* Created new keyboard file for testing "lets_split_eh" will merge into lets_split once fully functional

* Added split code from lets_split, removed pro micro imports and LED code

THIS IS WORKING CODE, WITHOUT RGB AND BACKLIGHT

* Took back original Lets Slit files for the lets_split keyboard, working in the lets_split_eh folder for now

* Updated eh.c

* More rework of the I2C code, added global flags for split boards.

* Introduced RGB over I2C, having weird edge case issues at the moment though

* Fixed weird I2C edgecase with RGB, although still would like to track down route cause..

* Changed RGB keycodes (static ones) to activate on key-up instead of key-down to elimate weird ghosting issue over I2C

* Lots of changes, mainly externalized the Split keyboard code and added logic for only including when needed.

- Added makefile option "SPLIT_KEYBOARD" that when = yes will include the split keyboard files and custom matrix
- Split keyboard files placed into quantum/split_common/
- Added define option for config files "SPLIT_HAND_PIN" FOr using high/low pin to determine handedness, low = right hand, high = left hand
- Cleaned up split logic for RGB and Backlight so it is only exectuted / included when needed

* Updated documentation for the new makefile options and #defines specific to split keyboards

* Added a bit more info to docs, so people aren't confused

* Modifed Let's Split to use externalized code, also added left and right hand eeprom files to the split_common folder

* Removed some debugging from eh.c

* Small changes to keyboard configs. Also added a default keymap (just a copy of my that_canadian keymap).

* Added a README file to the Let's Split Eh?

* Changed it so RGB static updates are done on key-up ONLY for split boards rather than all boards. Also fixed leftover un-used variable in rgblight.c

* Updated default keymap and my keymap for Let's Split Eh? Updated the comments so it reflects RGB control, and removed audio functions.

* Fixed lets_split_eh not having a default version

* Removed "eh" references from lets_split folder for now

* Took lets_split folder from master to fix travis build errors, weird my local was overriding.

* Changed LAYOUT_ortho_4x12_kc -> LAYOUT_kc_ortho_4x12 to match bakingpy and others

* Removed rules.mk from my lets_split keymap, not needed

* Updated the config_options doc to better explain the usage of "#define SPLIT_HAND_PIN"

* Fixed split_common assuming I2C for RGB and Backlight. Added serial backlight support (stole from bakingpy's Levinson code ;) ) Serial RGB not implemented yet. Also Added "USE_IC2" to the lets_split_eh/eh as that was looked over.

* Fixed stupid mistake, forgot to set BACKLIT_DIRTY to false after setting slave backlit settings for serial

* Updated backlight data block to be cleaner (thanks drashna ;) )

3 files changed, 44 insertions, 22 deletions

diff --git a/quantum/split_common/matrix.c b/quantum/split_common/matrix.c
index 071f0481a4..5e5475f44c 100644
--- a/quantum/split_common/matrix.c
+++ b/quantum/split_common/matrix.c
@@ -286,6 +286,16 @@ int serial_transaction(void) {
     for (int i = 0; i < ROWS_PER_HAND; ++i) {
         matrix[slaveOffset+i] = serial_slave_buffer[i];
     }
+    
+    #ifdef RGBLIGHT_ENABLE
+        // Code to send RGB over serial goes here (not implemented yet)
+    #endif
+    
+    #ifdef BACKLIGHT_ENABLE
+        // Write backlight level for slave to read
+        serial_master_buffer[SERIAL_BACKLIT_START] = backlight_config.enable ? backlight_config.level : 0;
+    #endif
+
     return 0;
 }
 #endif
diff --git a/quantum/split_common/serial.h b/quantum/split_common/serial.h
index 15fe4db7b4..e566eb8a06 100644
--- a/quantum/split_common/serial.h
+++ b/quantum/split_common/serial.h
@@ -14,6 +14,9 @@
 #define SERIAL_SLAVE_BUFFER_LENGTH MATRIX_ROWS/2
 #define SERIAL_MASTER_BUFFER_LENGTH 1
 
+// Address location defines 
+#define SERIAL_BACKLIT_START   0x00
+
 // Buffers for master - slave communication
 extern volatile uint8_t serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH];
 extern volatile uint8_t serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH];
diff --git a/quantum/split_common/split_util.c b/quantum/split_common/split_util.c
index 340a631375..13b09d5b81 100644
--- a/quantum/split_common/split_util.c
+++ b/quantum/split_common/split_util.c
@@ -101,35 +101,44 @@ void keyboard_slave_loop(void) {
    #endif
 
    while (1) {
-      matrix_slave_scan();
-      
-      // read backlight info
+    // Matrix Slave Scan
+    matrix_slave_scan();
+    
+    // Read Backlight Info
     #ifdef BACKLIGHT_ENABLE
         if (BACKLIT_DIRTY) {
-            backlight_set(i2c_slave_buffer[I2C_BACKLIT_START]);
+            #ifdef USE_I2C
+                backlight_set(i2c_slave_buffer[I2C_BACKLIT_START]);
+            #else // USE_SERIAL
+                backlight_set(serial_master_buffer[SERIAL_BACKLIT_START]);
+            #endif
             BACKLIT_DIRTY = false;
         }
     #endif
+    // Read RGB Info
     #ifdef RGBLIGHT_ENABLE
-        if (RGB_DIRTY) {
-            cli();
-            uint32_t dword;
-            
-            /*dword = i2c_slave_buffer[I2C_RGB_START + 3];
-            dword = (dword << 8) + i2c_slave_buffer[I2C_RGB_START + 2];
-            dword = (dword << 8) + i2c_slave_buffer[I2C_RGB_START + 1];
-            dword = (dword << 8) + i2c_slave_buffer[I2C_RGB_START];*/
-            
-            
-            uint8_t *dword_dat = (uint8_t *)(&dword);
-            for (int i = 0; i < 4; i++) {
-                dword_dat[i] = i2c_slave_buffer[I2C_RGB_START+i];
+        #ifdef USE_I2C
+            if (RGB_DIRTY) {
+                // Disable interupts (RGB data is big)
+                cli();
+                // Create new DWORD for RGB data
+                uint32_t dword; 
+                
+                // Fill the new DWORD with the data that was sent over
+                uint8_t *dword_dat = (uint8_t *)(&dword);
+                for (int i = 0; i < 4; i++) {
+                    dword_dat[i] = i2c_slave_buffer[I2C_RGB_START+i];
+                }
+                
+                // Update the RGB now with the new data and set RGB_DIRTY to false
+                rgblight_update_dword(dword);
+                RGB_DIRTY = false;
+                // Re-enable interupts now that RGB is set
+                sei();
             }
-
-            rgblight_update_dword(dword);
-            RGB_DIRTY = false;
-            sei();
-        }
+        #else // USE_SERIAL
+            // Add serial implementation for RGB here
+        #endif
     #endif
    }
 }