Add stephen-huan keymap and fix LED problem in the default Plaid keymap (#9306)

* change layers, add pinmode to fix LEDs

* fix LEDs by setting the pin mode

* edit README

* edit GPIO documentation, edit keymap

* add markov chain

* simplify LED logic

* undo documentation changes

* keymap changes, fix LED enum logic

3 files changed, 376 insertions, 0 deletions

diff --git a/keyboards/dm9records/plaid/keymaps/stephen-huan/config.h b/keyboards/dm9records/plaid/keymaps/stephen-huan/config.h
new file mode 100644
index 0000000000..5733b9e4b0
--- /dev/null
+++ b/keyboards/dm9records/plaid/keymaps/stephen-huan/config.h
@@ -0,0 +1,19 @@
+/* Copyright 2019 Takuya Urakawa (dm9records.com)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+// place overrides here
diff --git a/keyboards/dm9records/plaid/keymaps/stephen-huan/keymap.c b/keyboards/dm9records/plaid/keymaps/stephen-huan/keymap.c
new file mode 100644
index 0000000000..c8d48c3955
--- /dev/null
+++ b/keyboards/dm9records/plaid/keymaps/stephen-huan/keymap.c
@@ -0,0 +1,356 @@
+/* Copyright 2019 Takuya Urakawa (dm9records.com)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include QMK_KEYBOARD_H
+
+
+enum plaid_layers {
+  _QWERTY,
+  _LOWER,
+  _RAISE,
+  _ADJUST
+};
+
+enum plaid_keycodes {
+  QWERTY = SAFE_RANGE,
+  LED_1,
+  LED_2,
+  LED_3,
+  LED_4,
+  LED_5,
+  LED_6,
+  LED_7,
+  LED_8,
+  LED_9,
+  LED_0
+};
+
+#define LOWER MO(_LOWER)
+#define RAISE MO(_RAISE)
+
+// array of keys considered modifiers for led purposes
+const uint16_t modifiers[] = {
+    KC_LCTL,
+    KC_RCTL,
+    KC_LALT,
+    KC_RALT,
+    KC_LSFT,
+    KC_RSFT,
+    KC_LGUI,
+    KC_RGUI,
+    LOWER,
+    RAISE
+};
+
+//Setup consts for LED modes
+#define LEDMODE_ON 1 //always on
+#define LEDMODE_OFF 0 //always off
+#define LEDMODE_MODS 2 //On with modifiers
+#define LEDMODE_BLINKIN 3 //blinkinlights - % chance toggle on keypress
+#define LEDMODE_KEY 4 //On with any keypress, off with key release
+#define LEDMODE_ENTER 5 // On with enter key
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+/* Qwerty
+ * ,-----------------------------------------------------------------------------------.
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |   Y  |   U  |   I  |   O  |   P  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * |Esc/hy|   A  |   S  |   D  |   F  |   G  |   H  |   J  |   K  |   L  |   ;  |  "   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * | Shift|   Z  |   X  |   C  |   V  |   B  |   N  |   M  |   ,  |   .  |   /  |Enter |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * | Ctrl |  fn  | Alt  | GUI  |Lower |    Space    |Raise | GUI  | Alt  |Shift | Ctrl |
+ * `-----------------------------------------------------------------------------------'
+ *  (karabiner remaps Caps lock -> fn)
+ */
+[_QWERTY] = LAYOUT_plaid_grid(
+    KC_TAB        , KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_BSPC,
+    HYPR_T(KC_ESC), KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT,
+    KC_RSFT       , KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_ENT ,
+    KC_RCTL       , KC_CAPS, KC_RALT, KC_RGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_RGUI, KC_RALT, KC_RSFT, KC_RCTL
+),
+
+/* Lower
+ * ,-----------------------------------------------------------------------------------.
+ * |   `  |   1  |   2  |   3  |   4  |   5  |   6  |   7  |   8  |   9  |   0  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * |      |  F1  |  F2  |  F3  |  F4  |  F5  |  F6  |   -  |   =  |   [  |   ]  |  \   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |  F7  |  F8  |  F9  | F10  | F11  | F12  |      |      |      |      |      |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |             |      |      | Prev | Vol- | Play |
+ * `-----------------------------------------------------------------------------------'
+ * volume up key repeats randomly on mac, have to use mac specific volume
+ */
+[_LOWER] = LAYOUT_plaid_grid(
+    KC_GRV , KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0       , KC_BSPC,
+    _______, KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_MINS, KC_EQL,  KC_LBRC, KC_RBRC    , KC_BSLS,
+    _______, KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  _______, _______, _______, _______    , _______,
+    _______, _______, _______, _______, _______, _______, _______, _______, _______, KC_MPRV, KC__VOLDOWN, KC_MPLY
+),
+
+/* Raise
+ * ,-----------------------------------------------------------------------------------.
+ * |   ~  |      |      | End  |      |      |      |Pg Up |      |      |      | Del  |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * |      | Home |      |Pg Dn |      |      | Left | Down |  Up  |Right |      |      |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |      |      | Copy |Paste |      |      |      |      |      |      |      |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |             |      |      | Next | Vol+ | Mute |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_RAISE] = LAYOUT_plaid_grid(
+    KC_TILD, _______, _______, KC_END, _______, _______, _______,  KC_PGUP, _______, _______, _______  , KC_DEL , 
+    _______, KC_HOME, _______, KC_PGDN, _______, _______, KC_LEFT, KC_DOWN, KC_UP  , KC_RGHT, _______  , _______, 
+    _______, _______, _______, KC_COPY, KC_PSTE, KC_PGDN, _______, _______, _______, _______, _______  , _______,  
+    _______, _______, _______, _______, _______, _______, _______, _______, _______, KC_MNXT, KC__VOLUP, KC_MUTE
+),
+
+/* Adjust (Lower + Raise)
+ * ,-----------------------------------------------------------------------------------.
+ * |Reset | Red  |Green | Rmod | Gmod |Rblink|Gblink| Rkey | Gkey | Rcar | Gcar |      |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * |      |Power |Sleep |Wake  |Eject |      |      |      |      |      |      |      |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |      |      |      |      |      |      |      |      |      |      |      |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |             |      |      |      |      |      |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_ADJUST] = LAYOUT_plaid_grid(
+    RESET  , LED_1  , LED_2  ,  LED_3  , LED_4  , LED_5  ,LED_6   , LED_7  , LED_8  , LED_9  , LED_0  , _______ ,
+    _______, KC_PWR , KC_SLEP,  KC_WAKE, KC_EJCT, _______, _______, _______, _______, _______, _______, _______ ,
+    _______, _______, _______,  _______, _______, _______, _______, _______, _______, _______, _______, _______ ,
+    _______, _______, _______,  _______, _______, _______, _______, _______, _______, _______, _______, _______
+)
+
+
+};
+
+//Setup config struct for LED
+typedef union {
+  uint32_t raw;
+  struct {
+    uint8_t  red_mode :8;
+    uint8_t  green_mode :8;
+  };
+} led_config_t;
+led_config_t led_config;
+
+//Set leds to saved state during powerup
+void keyboard_post_init_user(void) {
+  // set LED pin modes
+  setPinOutput(LED_RED);
+  setPinOutput(LED_GREEN);
+
+  // Call the post init code.
+  led_config.raw = eeconfig_read_user();
+
+  if(led_config.red_mode == LEDMODE_ON) {
+      writePinHigh(LED_RED);
+  }
+
+  if(led_config.green_mode == LEDMODE_ON) {
+      writePinHigh(LED_GREEN);
+  }
+}
+
+void eeconfig_init_user(void) {  // EEPROM is getting reset! 
+  led_config.raw = 0;
+  led_config.red_mode = LEDMODE_ON;
+  led_config.green_mode = LEDMODE_MODS;
+  eeconfig_update_user(led_config.raw);
+}
+
+layer_state_t layer_state_set_user(layer_state_t state) {
+  return update_tri_layer_state(state, _LOWER, _RAISE, _ADJUST);
+}
+
+void led_keypress_update(uint8_t led, uint8_t led_mode, uint16_t keycode, keyrecord_t *record) {
+    switch (led_mode) {
+      case LEDMODE_MODS:
+        for (int i=0;i<sizeof(modifiers) / sizeof(modifiers[0]);i++) {
+          if(keycode==modifiers[i]) {
+            if (record->event.pressed) {
+              writePinHigh(led);
+            }
+            else {
+              writePinLow(led);
+            }
+          }
+        }
+        break;
+      case LEDMODE_BLINKIN:
+        if (record->event.pressed) {
+
+          /* Markov Chain
+           *
+           *   1 - x           1 - y
+           *   /---\           /---\
+           *   v   |           v   |
+           *  /------\   x   /------\
+           *  |      |------>|      |
+           *  |  on  |   y   | off  |
+           *  |      |<------|      |
+           *  \------/       \------/
+          */
+
+          /* Non-homogeneous Markov Chain
+           *
+           * /-----\ 1 - x0 /-----\ 1 - x1 /-----\  
+           * |on  0|------->|on  1|------->|on  2|----> ...  
+           * \-----/\      /\-----/\      /\-----/\
+           *         \    /         \    /         .
+           *        x0\  /         x1\  /           .
+           *           \/             \/             .
+           *           /\             /\              
+           *        y0/  \         y1/  \            .
+           *         /    \         /    \          .
+           *        /      \       /      \        .
+           * /-----\ 1 - y0 /-----\ 1 - y1 /-----\/  
+           * |off 0|------->|off 1|------->|off 2|----> ...
+           * \-----/        \-----/        \-----/  
+           *
+           *
+           * if x = 1/4 and y 1/4, behavior is equivalent to the original code
+           * and converges to a steady state at the rate of 1/2^k
+           * where k is the number of key presses
+           * (the distance from a given vector to the steady state, [1/2, 1/2], 
+           * is cut in half every key press)
+           *
+           * if x = y, then it is guaranteed that the steady state is still
+           * [1/2, 1/2], but the rate at which it converges is variable 
+           *
+           * if x != y, then there is no well-defined steady state
+          */
+
+          double x = (1.0*rand())/RAND_MAX;
+          double y = x;
+
+          double p = (readPin(led)) ? x : y;
+          if (rand() < p*RAND_MAX) {
+            togglePin(led);
+          }
+
+          /* following code is restriced to x + y <= 1
+           * if(rand() % 2 == 1) { */
+          /*   if(rand() % 2 == 0) { */
+          /*     writePinLow(led); */
+          /*   } */
+          /*   else { */
+          /*     writePinHigh(led); */
+          /*   } */
+          /* } */
+        }
+        break;
+      case LEDMODE_KEY:
+        if (record->event.pressed) {
+          writePinHigh(led);
+          return;
+        }
+        else {
+          writePinLow(led);
+          return;
+        }
+        break;
+      case LEDMODE_ENTER:
+        if (keycode==KC_ENT) {
+          writePinHigh(led);
+        }
+        else {
+          writePinLow(led);
+        }
+        break;
+
+    }
+}
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  /* If the either led mode is keypressed based, call the led updater
+     then let it fall through the keypress handlers. Just to keep 
+     the logic out of this procedure */
+  if (led_config.red_mode >= LEDMODE_MODS && led_config.red_mode <= LEDMODE_ENTER) {
+      led_keypress_update(LED_RED, led_config.red_mode, keycode, record);
+  }
+  if (led_config.green_mode >= LEDMODE_MODS && led_config.green_mode <= LEDMODE_ENTER) {
+      led_keypress_update(LED_GREEN, led_config.green_mode, keycode, record);
+  }
+  switch (keycode) {
+    case QWERTY:
+      if (record->event.pressed) {
+        print("mode just switched to qwerty and this is a huge string\n");
+        set_single_persistent_default_layer(_QWERTY);
+      }
+      return false;
+      break;
+    case LED_1:
+      if (record->event.pressed) {
+        if (led_config.red_mode==LEDMODE_ON) {
+            led_config.red_mode=LEDMODE_OFF;
+            writePinLow(LED_RED);
+        }
+        else {
+            led_config.red_mode=LEDMODE_ON;
+            writePinHigh(LED_RED);
+        }
+      }
+      break;
+    case LED_2:
+      if (record->event.pressed) {
+        if (led_config.green_mode==LEDMODE_ON) {
+            led_config.green_mode=LEDMODE_OFF;
+            writePinLow(LED_GREEN);
+        }
+        else {
+            led_config.green_mode=LEDMODE_ON;
+            writePinHigh(LED_GREEN);
+        }
+      }
+      break;
+    case LED_3:
+      led_config.red_mode=LEDMODE_MODS;
+      break;
+    case LED_4:
+      led_config.green_mode=LEDMODE_MODS;
+      break;
+    case LED_5:
+      led_config.red_mode=LEDMODE_BLINKIN;
+      break;
+    case LED_6:
+      led_config.green_mode=LEDMODE_BLINKIN;
+      break;
+    case LED_7:
+      led_config.red_mode=LEDMODE_KEY;
+      break;
+    case LED_8:
+      led_config.green_mode=LEDMODE_KEY;
+      break;
+    case LED_9:
+      led_config.red_mode=LEDMODE_ENTER;
+      break;
+    case LED_0:
+      led_config.green_mode=LEDMODE_ENTER;
+      break;
+  }
+
+  if (keycode >= LED_1 && keycode <= LED_0) {
+    eeconfig_update_user(led_config.raw);
+  }
+
+  return true;
+}
diff --git a/keyboards/dm9records/plaid/keymaps/stephen-huan/readme.md b/keyboards/dm9records/plaid/keymaps/stephen-huan/readme.md
new file mode 100644
index 0000000000..e52d24c3df
--- /dev/null
+++ b/keyboards/dm9records/plaid/keymaps/stephen-huan/readme.md
@@ -0,0 +1 @@
+# stephen-huan's keymap for Plaid