initial implementation for modifiers

#86

app/dts/behaviors.dtsi

@@ -1,4 +1,5 @@
 #include <behaviors/key_press.dtsi>
+#include <behaviors/modifiers.dtsi>
 #include <behaviors/transparent.dtsi>
 #include <behaviors/none.dtsi>
 #include <behaviors/mod_tap.dtsi>

app/dts/behaviors/modifiers.dtsi

@@ -0,0 +1,94 @@
+#include <dt-bindings/zmk/keys.h>
+
+/ {
+	behaviors {
+		ctl: behavior_ctl {
+			compatible = "zmk,behavior-key-press";
+			label = "MOD_CTRL";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LCTL)>;
+		};
+
+		sft: behavior_sft {
+			compatible = "zmk,behavior-key-press";
+			label = "MOD_SHIFT";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LSFT)>;
+		};
+
+		alt: behavior_alt {
+			compatible = "zmk,behavior-key-press";
+			label = "MOD_ALT";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LALT)>;
+		};
+
+		gui: behavior_gui {
+			compatible = "zmk,behavior-key-press";
+			label = "MOD_GUI";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LALT)>;
+		};
+
+
+	    rctl: behavior_rtcl {
+			compatible = "zmk,behavior-key-press";
+			label = "RCTL";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_RCTL)>;
+		};
+
+		rsft: behavior_rsft {
+			compatible = "zmk,behavior-key-press";
+			label = "RSFT";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_RALT)>;
+		};
+
+		ralt: behavior_ralt {
+			compatible = "zmk,behavior-key-press";
+			label = "RALT";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_RALT)>;
+		};
+
+		rgui: behavior_rgui {
+			compatible = "zmk,behavior-key-press";
+			label = "RGUI";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_RGUI)>;
+		};
+
+		ctl_alt: behavior_ctl_alt {
+			compatible = "zmk,behavior-key-press";
+			label = "CTL_ALT";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LCTL | MOD_LALT)>;
+		};
+
+		meh: behavior_meh {
+			compatible = "zmk,behavior-key-press";
+			label = "MEH";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LCTL | MOD_LSFT | MOD_LALT)>;
+		};
+
+		hypr: behavior_hypr {
+			compatible = "zmk,behavior-key-press";
+			label = "HYPR";
+			usage_page = <USAGE_KEYPAD>;
+			#binding-cells = <1>;
+            modifiers = <(MOD_LCTL | MOD_LSFT | MOD_LALT | MOD_LGUI)>;
+		};
+	};
+};

app/dts/bindings/behaviors/zmk,behavior-key-press.yaml

@@ -11,3 +11,6 @@ properties:
   usage_page:
     type: int
     default: 0
+  modifiers:
+    type: int
+    default: 0

app/include/dt-bindings/zmk/keys.h

@@ -146,4 +146,5 @@
 #define MOD_RCTL (1 << 0x04)
 #define MOD_RSFT (1 << 0x05)
 #define MOD_RALT (1 << 0x06)
-#define MOD_RGUI (1 << 0x07)
+#define MOD_RGUI (1 << 0x07)
+#define MOD_LAST_MODIFIER MOD_RGUI

app/src/behaviors/behavior_key_press.c

@@ -10,13 +10,15 @@
 #include <drivers/behavior.h>
 #include <logging/log.h>
 
+#include <zmk/hid.h>
 #include <zmk/event-manager.h>
 #include <zmk/events/keycode-state-changed.h>
 
 LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 
 struct behavior_key_press_config {
   u8_t usage_page;
+  zmk_mod_flags modifiers;
 };
 struct behavior_key_press_data { };
 
@@ -30,6 +32,7 @@ static int on_keymap_binding_pressed(struct device *dev, u32_t position, u32_t k
   const struct behavior_key_press_config *cfg = dev->config_info;
   LOG_DBG("position %d usage_page 0x%02X keycode 0x%02X", position, cfg->usage_page, keycode);
 
+  zmk_hid_register_mods(cfg->modifiers);
   return ZMK_EVENT_RAISE(create_keycode_state_changed(cfg->usage_page, keycode, true));
 }
 
@@ -38,6 +41,7 @@ static int on_keymap_binding_released(struct device *dev, u32_t position, u32_t
   const struct behavior_key_press_config *cfg = dev->config_info;
   LOG_DBG("position %d usage_page 0x%02X keycode 0x%02X", position, cfg->usage_page, keycode);
 
+  zmk_hid_unregister_mods(cfg->modifiers);
   return ZMK_EVENT_RAISE(create_keycode_state_changed(cfg->usage_page, keycode, false));
 }
 
@@ -48,7 +52,8 @@ static const struct behavior_driver_api behavior_key_press_driver_api = {
 
 #define KP_INST(n) \
   static const struct behavior_key_press_config behavior_key_press_config_##n = { \
-    .usage_page = DT_INST_PROP(n, usage_page) \
+    .usage_page = DT_INST_PROP(n, usage_page), \
+    .modifiers = DT_INST_PROP(n, modifiers), \
   }; \
   static struct behavior_key_press_data behavior_key_press_data_##n; \
   DEVICE_AND_API_INIT(behavior_key_press_##n, DT_INST_LABEL(n), behavior_key_press_init, \

app/src/hid.c

@@ -14,32 +14,58 @@ static struct zmk_hid_consumer_report consumer_report = {
     .body = {
         .keys = {0,0,0,0,0,0}}};
 
-#define _TOGGLE_MOD(mod, state)                      \
-    if (modifier > MOD_RGUI)                         \
-    {                                                \
-        return -EINVAL;                              \
-    }                                                \
-    WRITE_BIT(kp_report.body.modifiers, mod, state); \
-    return 0;
+// Keep track of how often a modifier was pressed.
+// Only release the modifier iff the count is 0.
+static int modifier_counts[8] = {0, 0, 0, 0, 0, 0, 0, 0};
 
 int zmk_hid_register_mod(zmk_mod modifier)
 {
-    _TOGGLE_MOD(modifier, true);
+    modifier_counts[modifier]++;
+    WRITE_BIT(kp_report.body.modifiers, modifier, true);
+    return 0;
 }
+
 int zmk_hid_unregister_mod(zmk_mod modifier)
 {
-    _TOGGLE_MOD(modifier, false);
+    if(modifier >= 8) {
+        LOG_ERR("This modifier does not exist %d", modifier);
+        return -EINVAL;
+    }
+    if(modifier_counts[modifier] <= 0) {
+        LOG_ERR("Tried to unregister modifier %d too often", modifier);
+        return -EINVAL;
+    }
+    modifier_counts[modifier]--;
+    if (modifier_counts[modifier] == 0) {
+        LOG_DBG("Modifier %d released.", modifier);
+        WRITE_BIT(kp_report.body.modifiers, modifier, false);
+    }
+    return 0;
 }
 
 int zmk_hid_register_mods(zmk_mod_flags modifiers)
 {
-    kp_report.body.modifiers |= modifiers;
+    for(int modifier = 0; modifier < 8; modifier++) {
+        if ((modifiers >> modifier) & 1) {
+            int ret;
+            if((ret = zmk_hid_register_mod(modifier)) < 0) {
+                return ret;
+            }
+        }
+    }
     return 0;
 }
 
 int zmk_hid_unregister_mods(zmk_mod_flags modifiers)
 {
-    kp_report.body.modifiers &= ~modifiers;
+    for(int modifier = 0; modifier < 8; modifier++) {
+        if ((modifiers >> modifier) & 1) {
+            int ret;
+            if((ret = zmk_hid_unregister_mod(modifier)) < 0) {
+                return ret;
+            }
+        }
+    }
     return 0;
 }
 

app/tests/keypress/kp-press-release-mod/events.patterns

@@ -0,0 +1,3 @@
+s/.*hid_listener_keycode_//p
+s/.*hid_register_mod/reg/p
+s/.*hid_unregister_mod/unreg/p

app/tests/keypress/kp-press-release-mod/keycode_events.snapshot

@@ -0,0 +1,5 @@
+pressed: usage_page 0x07 keycode 0x05
+pressed: usage_page 0x07 keycode 0x04
+released: usage_page 0x07 keycode 0x04
+unreg: Modifier 1 released.
+released: usage_page 0x07 keycode 0x05

app/tests/keypress/kp-press-release-mod/native_posix.keymap

@@ -0,0 +1,27 @@
+#include <dt-bindings/zmk/keys.h>
+#include <behaviors.dtsi>
+#include <dt-bindings/zmk/kscan-mock.h>
+
+
+&kscan {
+	events = <
+		ZMK_MOCK_PRESS(0,1,10) 
+		ZMK_MOCK_PRESS(0,0,10) 
+		ZMK_MOCK_RELEASE(0,0,10) 
+		ZMK_MOCK_RELEASE(0,1,10)
+	>;
+};
+
+/ {
+	keymap {
+		compatible = "zmk,keymap";
+		label ="Default keymap";
+
+		default_layer {
+			bindings = <
+				&sft A &sft B
+				&kp D &kp G
+			>;
+		};
+	};
+};