From c2d220fbdf2c9ae6957d080a47545aa28e3ec275 Mon Sep 17 00:00:00 2001
From: Peter Johanson <peter@peterjohanson.com>
Date: Wed, 8 Nov 2023 22:05:53 +0000
Subject: [PATCH] refactor(hid): Use proper defines for HID values.

* Add report ID defines and use them consistently.
* Add defines for main item value flags to avoid magic constants.
---
 app/include/zmk/hid.h | 51 ++++++++++++++++++++++++++++++++-----------
 app/src/hid.c         |  5 +++--
 app/src/hog.c         |  4 ++--
 3 files changed, 43 insertions(+), 17 deletions(-)

diff --git a/app/include/zmk/hid.h b/app/include/zmk/hid.h
index ab42adaa..da6bfa65 100644
--- a/app/include/zmk/hid.h
+++ b/app/include/zmk/hid.h
@@ -15,13 +15,43 @@
 
 #define ZMK_HID_KEYBOARD_NKRO_MAX_USAGE HID_USAGE_KEY_KEYPAD_EQUAL
 
-#define COLLECTION_REPORT 0x03
+// See https://www.usb.org/sites/default/files/hid1_11.pdf section 6.2.2.4 Main Items
+
+#define ZMK_HID_MAIN_VAL_DATA (0x00 << 0)
+#define ZMK_HID_MAIN_VAL_CONST (0x01 << 0)
+
+#define ZMK_HID_MAIN_VAL_ARRAY (0x00 << 1)
+#define ZMK_HID_MAIN_VAL_VAR (0x01 << 1)
+
+#define ZMK_HID_MAIN_VAL_ABS (0x00 << 2)
+#define ZMK_HID_MAIN_VAL_REL (0x01 << 2)
+
+#define ZMK_HID_MAIN_VAL_NO_WRAP (0x00 << 3)
+#define ZMK_HID_MAIN_VAL_WRAP (0x01 << 3)
+
+#define ZMK_HID_MAIN_VAL_LIN (0x00 << 4)
+#define ZMK_HID_MAIN_VAL_NON_LIN (0x01 << 4)
+
+#define ZMK_HID_MAIN_VAL_PREFERRED (0x00 << 5)
+#define ZMK_HID_MAIN_VAL_NO_PREFERRED (0x01 << 5)
+
+#define ZMK_HID_MAIN_VAL_NO_NULL (0x00 << 6)
+#define ZMK_HID_MAIN_VAL_NULL (0x01 << 6)
+
+#define ZMK_HID_MAIN_VAL_NON_VOL (0x00 << 7)
+#define ZMK_HID_MAIN_VAL_VOL (0x01 << 7)
+
+#define ZMK_HID_MAIN_VAL_BIT_FIELD (0x00 << 8)
+#define ZMK_HID_MAIN_VAL_BUFFERED_BYTES (0x01 << 8)
+
+#define ZMK_HID_REPORT_ID_KEYBOARD 0x01
+#define ZMK_HID_REPORT_ID_CONSUMER 0x02
 
 static const uint8_t zmk_hid_report_desc[] = {
     HID_USAGE_PAGE(HID_USAGE_GEN_DESKTOP),
     HID_USAGE(HID_USAGE_GD_KEYBOARD),
     HID_COLLECTION(HID_COLLECTION_APPLICATION),
-    HID_REPORT_ID(0x01),
+    HID_REPORT_ID(ZMK_HID_REPORT_ID_KEYBOARD),
     HID_USAGE_PAGE(HID_USAGE_KEY),
     HID_USAGE_MIN8(HID_USAGE_KEY_KEYBOARD_LEFTCONTROL),
     HID_USAGE_MAX8(HID_USAGE_KEY_KEYBOARD_RIGHT_GUI),
@@ -30,14 +60,12 @@ static const uint8_t zmk_hid_report_desc[] = {
 
     HID_REPORT_SIZE(0x01),
     HID_REPORT_COUNT(0x08),
-    /* INPUT (Data,Var,Abs) */
-    HID_INPUT(0x02),
+    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),
 
     HID_USAGE_PAGE(HID_USAGE_KEY),
     HID_REPORT_SIZE(0x08),
     HID_REPORT_COUNT(0x01),
-    /* INPUT (Cnst,Var,Abs) */
-    HID_INPUT(0x03),
+    HID_INPUT(ZMK_HID_MAIN_VAL_CONST | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),
 
     HID_USAGE_PAGE(HID_USAGE_KEY),
 
@@ -48,8 +76,7 @@ static const uint8_t zmk_hid_report_desc[] = {
     HID_USAGE_MAX8(ZMK_HID_KEYBOARD_NKRO_MAX_USAGE),
     HID_REPORT_SIZE(0x01),
     HID_REPORT_COUNT(ZMK_HID_KEYBOARD_NKRO_MAX_USAGE + 1),
-    /* INPUT (Data,Ary,Abs) */
-    HID_INPUT(0x02),
+    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),
 #elif IS_ENABLED(CONFIG_ZMK_HID_REPORT_TYPE_HKRO)
     HID_LOGICAL_MIN8(0x00),
     HID_LOGICAL_MAX16(0xFF, 0x00),
@@ -57,8 +84,7 @@ static const uint8_t zmk_hid_report_desc[] = {
     HID_USAGE_MAX8(0xFF),
     HID_REPORT_SIZE(0x08),
     HID_REPORT_COUNT(CONFIG_ZMK_HID_KEYBOARD_REPORT_SIZE),
-    /* INPUT (Data,Ary,Abs) */
-    HID_INPUT(0x00),
+    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_ARRAY | ZMK_HID_MAIN_VAL_ABS),
 #else
 #error "A proper HID report type must be selected"
 #endif
@@ -67,7 +93,7 @@ static const uint8_t zmk_hid_report_desc[] = {
     HID_USAGE_PAGE(HID_USAGE_CONSUMER),
     HID_USAGE(HID_USAGE_CONSUMER_CONSUMER_CONTROL),
     HID_COLLECTION(HID_COLLECTION_APPLICATION),
-    HID_REPORT_ID(0x02),
+    HID_REPORT_ID(ZMK_HID_REPORT_ID_CONSUMER),
     HID_USAGE_PAGE(HID_USAGE_CONSUMER),
 
 #if IS_ENABLED(CONFIG_ZMK_HID_CONSUMER_REPORT_USAGES_BASIC)
@@ -86,8 +112,7 @@ static const uint8_t zmk_hid_report_desc[] = {
 #error "A proper consumer HID report usage range must be selected"
 #endif
     HID_REPORT_COUNT(CONFIG_ZMK_HID_CONSUMER_REPORT_SIZE),
-    /* INPUT (Data,Ary,Abs) */
-    HID_INPUT(0x00),
+    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_ARRAY | ZMK_HID_MAIN_VAL_ABS),
     HID_END_COLLECTION,
 };
 
diff --git a/app/src/hid.c b/app/src/hid.c
index 2a6b5d39..58e5824d 100644
--- a/app/src/hid.c
+++ b/app/src/hid.c
@@ -12,9 +12,10 @@ LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 #include <dt-bindings/zmk/modifiers.h>
 
 static struct zmk_hid_keyboard_report keyboard_report = {
-    .report_id = 1, .body = {.modifiers = 0, ._reserved = 0, .keys = {0}}};
+    .report_id = ZMK_HID_REPORT_ID_KEYBOARD, .body = {.modifiers = 0, ._reserved = 0, .keys = {0}}};
 
-static struct zmk_hid_consumer_report consumer_report = {.report_id = 2, .body = {.keys = {0}}};
+static struct zmk_hid_consumer_report consumer_report = {.report_id = ZMK_HID_REPORT_ID_CONSUMER,
+                                                         .body = {.keys = {0}}};
 
 // Keep track of how often a modifier was pressed.
 // Only release the modifier if the count is 0.
diff --git a/app/src/hog.c b/app/src/hog.c
index 930714b0..9ccfd9d2 100644
--- a/app/src/hog.c
+++ b/app/src/hog.c
@@ -47,12 +47,12 @@ enum {
 };
 
 static struct hids_report input = {
-    .id = 0x01,
+    .id = ZMK_HID_REPORT_ID_KEYBOARD,
     .type = HIDS_INPUT,
 };
 
 static struct hids_report consumer_input = {
-    .id = 0x02,
+    .id = ZMK_HID_REPORT_ID_CONSUMER,
     .type = HIDS_INPUT,
 };