[PATCH v2] HID: magicmouse: add haptic click configuration for Magic Trackpad 2
From: Christian Fressl
Date: Thu May 14 2026 - 13:19:47 EST
Apple Magic Trackpad 2 devices support persistent haptic feedback
configuration through feature reports 0x22 and 0x23. Add an opt-in
module parameter to select either the verified silent-low profile or to
disable haptic feedback.
The default remains unchanged. The report payload format is
reverse-engineered, so keep the existing payload bytes fixed and vary
only the known 24-bit feedback value.
The USB-C Trackpad exposes multiple HID interfaces. Use the one-shot
actuator output report 0x53 only to identify the interface that accepts
the persistent configuration reports; do not use it for the persistent
setting itself.
Tested on Apple Magic Trackpad USB-C 05ac:0324 with Ubuntu
6.17.0-23-generic. Compile-tested against HID for-next.
Protocol information was derived from public reverse-engineering notes,
then independently tested with local hardware.
Link: https://github.com/mwyborski/Linux-Magic-Trackpad-2-Driver/issues/28#issuecomment-451625504
Signed-off-by: Christian Fressl <christian@xxxxxxxxx>
---
Changes in v2:
- Cache haptic_click with READ_ONCE() before applying the setting.
drivers/hid/hid-magicmouse.c | 102 ++++++++++++++++++++++++++++++++++-
1 file changed, 101 insertions(+), 1 deletion(-)
diff --git a/drivers/hid/hid-magicmouse.c b/drivers/hid/hid-magicmouse.c
index e70bd3dc07ab..e941c95f0703 100644
--- a/drivers/hid/hid-magicmouse.c
+++ b/drivers/hid/hid-magicmouse.c
@@ -51,6 +51,10 @@ static bool report_undeciphered;
module_param(report_undeciphered, bool, 0644);
MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state field using a MSC_RAW event");
+static unsigned int haptic_click;
+module_param(haptic_click, uint, 0644);
+MODULE_PARM_DESC(haptic_click, "Haptic click feedback: 0=unchanged, 1=silent-low, 2=off");
+
#define TRACKPAD2_2021_BT_VERSION 0x110
#define TRACKPAD_2024_BT_VERSION 0x314
@@ -62,6 +66,17 @@ MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state fie
#define DOUBLE_REPORT_ID 0xf7
#define USB_BATTERY_TIMEOUT_SEC 60
+#define TRACKPAD2_HAPTIC_CLICK_REPORT_ID 0x22
+#define TRACKPAD2_HAPTIC_RELEASE_REPORT_ID 0x23
+#define TRACKPAD2_HAPTIC_ACTUATOR_REPORT_ID 0x53
+#define TRACKPAD2_HAPTIC_REPORT_LEN 14
+#define TRACKPAD2_HAPTIC_CLICK_UNCHANGED 0
+#define TRACKPAD2_HAPTIC_CLICK_SILENT_LOW 1
+#define TRACKPAD2_HAPTIC_CLICK_OFF 2
+#define TRACKPAD2_HAPTIC_SILENT_CLICK 0x000015
+#define TRACKPAD2_HAPTIC_SILENT_RELEASE 0x000010
+#define TRACKPAD2_HAPTIC_OFF 0x000000
+
/* These definitions are not precise, but they're close enough. (Bits
* 0x03 seem to indicate the aspect ratio of the touch, bits 0x70 seem
* to be some kind of bit mask -- 0x20 may be a near-field reading,
@@ -812,6 +827,82 @@ static bool is_usb_magictrackpad2(__u32 vendor, __u32 product)
product == USB_DEVICE_ID_APPLE_MAGICTRACKPAD2_USBC;
}
+static bool magicmouse_is_haptic_interface(struct hid_device *hdev)
+{
+ struct hid_report_enum *report_enum;
+
+ report_enum = &hdev->report_enum[HID_OUTPUT_REPORT];
+
+ /*
+ * The persistent haptic configuration reports are accepted as feature
+ * reports, but are not advertised in the feature report descriptor.
+ * Report 0x53 is the one-shot actuator output report and identifies
+ * the HID interface that accepts the persistent reports.
+ */
+ return report_enum->report_id_hash[TRACKPAD2_HAPTIC_ACTUATOR_REPORT_ID];
+}
+
+static int magicmouse_send_haptic_report(struct hid_device *hdev, u8 report_id,
+ u32 feedback)
+{
+ static const u8 report_template[TRACKPAD2_HAPTIC_REPORT_LEN] = {
+ 0x00, 0x01, 0x00, 0x78, 0x02, 0x00, 0x24,
+ 0x30, 0x06, 0x01, 0x00, 0x18, 0x48, 0x13,
+ };
+ u8 *buf;
+ int ret;
+
+ buf = kmemdup(report_template, sizeof(report_template), GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ buf[0] = report_id;
+ buf[2] = feedback & 0xff;
+ buf[5] = (feedback >> 8) & 0xff;
+ buf[10] = (feedback >> 16) & 0xff;
+
+ ret = hid_hw_raw_request(hdev, buf[0], buf, TRACKPAD2_HAPTIC_REPORT_LEN,
+ HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+ kfree(buf);
+
+ return ret;
+}
+
+static int magicmouse_apply_haptic_click(struct hid_device *hdev)
+{
+ unsigned int click = READ_ONCE(haptic_click);
+ u32 click_feedback;
+ u32 release_feedback;
+ int ret;
+
+ if (click == TRACKPAD2_HAPTIC_CLICK_UNCHANGED)
+ return 0;
+
+ switch (click) {
+ case TRACKPAD2_HAPTIC_CLICK_SILENT_LOW:
+ click_feedback = TRACKPAD2_HAPTIC_SILENT_CLICK;
+ release_feedback = TRACKPAD2_HAPTIC_SILENT_RELEASE;
+ break;
+ case TRACKPAD2_HAPTIC_CLICK_OFF:
+ click_feedback = TRACKPAD2_HAPTIC_OFF;
+ release_feedback = TRACKPAD2_HAPTIC_OFF;
+ break;
+ default:
+ hid_warn(hdev, "invalid haptic_click value %u\n", click);
+ return -EINVAL;
+ }
+
+ ret = magicmouse_send_haptic_report(hdev,
+ TRACKPAD2_HAPTIC_CLICK_REPORT_ID,
+ click_feedback);
+ if (ret < 0)
+ return ret;
+
+ return magicmouse_send_haptic_report(hdev,
+ TRACKPAD2_HAPTIC_RELEASE_REPORT_ID,
+ release_feedback);
+}
+
static int magicmouse_fetch_battery(struct hid_device *hdev)
{
#ifdef CONFIG_HID_BATTERY_STRENGTH
@@ -894,8 +985,17 @@ static int magicmouse_probe(struct hid_device *hdev,
if (is_usb_magicmouse2(id->vendor, id->product) ||
(is_usb_magictrackpad2(id->vendor, id->product) &&
- hdev->type != HID_TYPE_USBMOUSE))
+ hdev->type != HID_TYPE_USBMOUSE)) {
+ if (is_usb_magictrackpad2(id->vendor, id->product) &&
+ magicmouse_is_haptic_interface(hdev)) {
+ ret = magicmouse_apply_haptic_click(hdev);
+ if (ret < 0)
+ hid_warn(hdev,
+ "unable to apply haptic click setting (%d)\n",
+ ret);
+ }
return 0;
+ }
if (!msc->input) {
hid_err(hdev, "magicmouse input not registered\n");
--
2.43.0