From 342d83891301b1be53233a12c7723bb99cbe5ff6 Mon Sep 17 00:00:00 2001
From: Tobias Adolph <43353209+adolto@users.noreply.github.com>
Date: Sun, 20 Jul 2025 17:13:18 +0200
Subject: [PATCH] fix(ble,hid): Fix smooth scrolling over BLE (#2998)

- Use correct MIN16 value in hid report. -32768 in 2's compliment is 8000(hex)
- Initialize resolution multiplier array
- Properly implement `read_hids_mouse_feature_report`

Fixes: #2957

Co-authored-by: Tobias Adolph <43353209+adolto@users.noreply.github.comgit>
---
 app/include/zmk/hid.h                     |  6 +++---
 app/src/hog.c                             | 25 ++++++++++++++++++++---
 app/src/pointing/resolution_multipliers.c |  8 +++++++-
 3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/app/include/zmk/hid.h b/app/include/zmk/hid.h
index 8a3f40b1b..962180e70 100644
--- a/app/include/zmk/hid.h
+++ b/app/include/zmk/hid.h
@@ -208,7 +208,7 @@ static const uint8_t zmk_hid_report_desc[] = {
     HID_USAGE_PAGE(HID_USAGE_GEN_DESKTOP),
     HID_USAGE(HID_USAGE_GD_X),
     HID_USAGE(HID_USAGE_GD_Y),
-    HID_LOGICAL_MIN16(0xFF, -0x7F),
+    HID_LOGICAL_MIN16(0x00, 0x80),
     HID_LOGICAL_MAX16(0xFF, 0x7F),
     HID_REPORT_SIZE(0x10),
     HID_REPORT_COUNT(0x02),
@@ -226,7 +226,7 @@ static const uint8_t zmk_hid_report_desc[] = {
     HID_FEATURE(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),
 #endif // IS_ENABLED(CONFIG_ZMK_POINTING_SMOOTH_SCROLLING)
     HID_USAGE(HID_USAGE_GD_WHEEL),
-    HID_LOGICAL_MIN16(0xFF, -0x7F),
+    HID_LOGICAL_MIN16(0x00, 0x80),
     HID_LOGICAL_MAX16(0xFF, 0x7F),
     HID_PHYSICAL_MIN8(0x00),
     HID_PHYSICAL_MAX8(0x00),
@@ -242,7 +242,7 @@ static const uint8_t zmk_hid_report_desc[] = {
 #endif // IS_ENABLED(CONFIG_ZMK_POINTING_SMOOTH_SCROLLING)
     HID_USAGE_PAGE(HID_USAGE_CONSUMER),
     HID_USAGE16_SINGLE(HID_USAGE_CONSUMER_AC_PAN),
-    HID_LOGICAL_MIN16(0xFF, -0x7F),
+    HID_LOGICAL_MIN16(0x00, 0x80),
     HID_LOGICAL_MAX16(0xFF, 0x7F),
     HID_PHYSICAL_MIN8(0x00),
     HID_PHYSICAL_MAX8(0x00),
diff --git a/app/src/hog.c b/app/src/hog.c
index d56eacf76..c7d9b861d 100644
--- a/app/src/hog.c
+++ b/app/src/hog.c
@@ -168,9 +168,28 @@ static ssize_t read_hids_mouse_input_report(struct bt_conn *conn, const struct b
 
 static ssize_t read_hids_mouse_feature_report(struct bt_conn *conn, const struct bt_gatt_attr *attr,
                                               void *buf, uint16_t len, uint16_t offset) {
-    struct zmk_hid_mouse_report_body *report_body = &zmk_hid_get_mouse_report()->body;
-    return bt_gatt_attr_read(conn, attr, buf, len, offset, report_body,
-                             sizeof(struct zmk_hid_mouse_report_body));
+
+    int profile = zmk_ble_profile_index(bt_conn_get_dst(conn));
+    if (profile < 0) {
+        LOG_DBG("   BT_ATT_ERR_UNLIKELY");
+        return BT_GATT_ERR(BT_ATT_ERR_UNLIKELY);
+    }
+
+    struct zmk_endpoint_instance endpoint = {
+        .transport = ZMK_TRANSPORT_BLE,
+        .ble = {.profile_index = profile},
+    };
+
+    struct zmk_pointing_resolution_multipliers mult =
+        zmk_pointing_resolution_multipliers_get_profile(endpoint);
+
+    struct zmk_hid_mouse_resolution_feature_report_body report = {
+        .wheel_res = mult.wheel,
+        .hwheel_res = mult.hor_wheel,
+    };
+
+    return bt_gatt_attr_read(conn, attr, buf, len, offset, &report,
+                             sizeof(struct zmk_hid_mouse_resolution_feature_report_body));
 }
 
 static ssize_t write_hids_mouse_feature_report(struct bt_conn *conn,
diff --git a/app/src/pointing/resolution_multipliers.c b/app/src/pointing/resolution_multipliers.c
index 951d104af..3ebda9d57 100644
--- a/app/src/pointing/resolution_multipliers.c
+++ b/app/src/pointing/resolution_multipliers.c
@@ -13,7 +13,13 @@
 
 LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 
-static struct zmk_pointing_resolution_multipliers multipliers[ZMK_ENDPOINT_COUNT];
+static struct zmk_pointing_resolution_multipliers multipliers[ZMK_ENDPOINT_COUNT] = {
+    [0 ... ZMK_ENDPOINT_COUNT - 1] =
+        {
+            .wheel = 15,
+            .hor_wheel = 15,
+        },
+};
 
 struct zmk_pointing_resolution_multipliers
 zmk_pointing_resolution_multipliers_get_current_profile(void) {