Merge remote-tracking branch 'upstream/master'

* upstream/master: (1239 commits)
  Update ez.c
  removes planck/rev3 temporarily
  Move hand_swap_config to ez.c, removes error for infinity
  Update Makefile
  ergodox: Update algernon's keymap to v1.9
  Added VS Code dir to .gitignore
  Support the Pegasus Hoof controller.
  [Jack & Erez] Simplifies and documents TO
  add readme
  use wait_ms instead of _delay_ms
  add messenger
  init keymap
  Add example keymap
  Adding whiskey_tango_foxtrot_capslock ergodox keymap
  Unicode map framework. Allow unicode up to 0xFFFFF using separate mapping table
  CIE 1931 dim curve
  Apply the dim curve to the RGB output
  Update the Cluecard readme files
  Tune snake and knight intervals for Cluecard
  Tunable RGB light intervals
  ...

1 files changed, 142 insertions, 0 deletions

diff --git a/quantum/serial_link/protocol/byte_stuffer.c b/quantum/serial_link/protocol/byte_stuffer.c
new file mode 100644
index 0000000000..2c87d64c29
--- /dev/null
+++ b/quantum/serial_link/protocol/byte_stuffer.c
@@ -0,0 +1,142 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Fred Sundvik
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#include "serial_link/protocol/byte_stuffer.h"
+#include "serial_link/protocol/frame_validator.h"
+#include "serial_link/protocol/physical.h"
+#include <stdbool.h>
+
+// This implements the "Consistent overhead byte stuffing protocol"
+// https://en.wikipedia.org/wiki/Consistent_Overhead_Byte_Stuffing
+// http://www.stuartcheshire.org/papers/COBSforToN.pdf
+
+typedef struct byte_stuffer_state {
+    uint16_t next_zero;
+    uint16_t data_pos;
+    bool long_frame;
+    uint8_t data[MAX_FRAME_SIZE];
+}byte_stuffer_state_t;
+
+static byte_stuffer_state_t states[NUM_LINKS];
+
+void init_byte_stuffer_state(byte_stuffer_state_t* state) {
+    state->next_zero = 0;
+    state->data_pos = 0;
+    state->long_frame = false;
+}
+
+void init_byte_stuffer(void) {
+    int i;
+    for (i=0;i<NUM_LINKS;i++) {
+        init_byte_stuffer_state(&states[i]);
+    }
+}
+
+void byte_stuffer_recv_byte(uint8_t link, uint8_t data) {
+    byte_stuffer_state_t* state = &states[link];
+    // Start of a new frame
+    if (state->next_zero == 0) {
+        state->next_zero = data;
+        state->long_frame = data == 0xFF;
+        state->data_pos = 0;
+        return;
+    }
+
+    state->next_zero--;
+    if (data == 0) {
+        if (state->next_zero == 0) {
+            // The frame is completed
+            if (state->data_pos > 0) {
+                validator_recv_frame(link, state->data, state->data_pos);
+            }
+        }
+        else {
+            // The frame is invalid, so reset
+            init_byte_stuffer_state(state);
+        }
+    }
+    else {
+        if (state->data_pos == MAX_FRAME_SIZE) {
+            // We exceeded our maximum frame size
+            // therefore there's nothing else to do than reset to a new frame
+            state->next_zero = data;
+            state->long_frame = data == 0xFF;
+            state->data_pos = 0;
+        }
+        else if (state->next_zero == 0) {
+            if (state->long_frame) {
+                // This is part of a long frame, so continue
+                state->next_zero = data;
+                state->long_frame = data == 0xFF;
+            }
+            else {
+                // Special case for zeroes
+                state->next_zero = data;
+                state->data[state->data_pos++] = 0;
+            }
+        }
+        else {
+            state->data[state->data_pos++] = data;
+        }
+    }
+}
+
+static void send_block(uint8_t link, uint8_t* start, uint8_t* end, uint8_t num_non_zero) {
+    send_data(link, &num_non_zero, 1);
+    if (end > start) {
+        send_data(link, start, end-start);
+    }
+}
+
+void byte_stuffer_send_frame(uint8_t link, uint8_t* data, uint16_t size) {
+    const uint8_t zero = 0;
+    if (size > 0) {
+        uint16_t num_non_zero = 1;
+        uint8_t* end = data + size;
+        uint8_t* start = data;
+        while (data < end) {
+            if (num_non_zero == 0xFF) {
+                // There's more data after big non-zero block
+                // So send it, and start a new block
+                send_block(link, start, data, num_non_zero);
+                start = data;
+                num_non_zero = 1;
+            }
+            else {
+                if (*data == 0) {
+                    // A zero encountered, so send the block
+                    send_block(link, start, data, num_non_zero);
+                    start = data + 1;
+                    num_non_zero = 1;
+                }
+                else {
+                    num_non_zero++;
+                }
+                ++data;
+            }
+        }
+        send_block(link, start, data, num_non_zero);
+        send_data(link, &zero, 1);
+    }
+}