Files
bfe-core1106-sdk/kernel/rv1106-enablement/touch/VERIFIED.md
T
BFE EngineeringandClaude Opus 4.8 189f7aec38 sdk: bootstrap standalone repo (P0)
- Dual license (LICENSE / LICENSE-MIT / LICENSE-APACHE) matching the crate manifests.
- ADRs 0001-0005: kernel base (direct 5.10->6.18.46 forward-port), tiered MC/DC,
  standalone repo, CI runner (3rd repo-scoped runner on 0640), driver source-of-truth.
- README goal 1 reconciled to the verified 6.18.46 forward-port (was stale plan44/6.6).
- Drop tracked build objects (*.o now gitignored).
- Capture the display (VOP dclk-pol + WIN1) and GT911 touch bring-up VERIFIED docs
  + capabilities-audit update from this session.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017wB8KB3MMQztRDXCMCkPrf
2026-08-25 13:46:08 -06:00

2.4 KiB

GT911 capacitive touch — VERIFIED on warden-c8a3 (2026-08-25)

Touch works on our self-built 6.18.46 (_b): the WardenOS UI responds to taps/swipes ([maintainer] confirmed on the physical panel). Objective evidence:

Goodix-TS 3-0014: ID 911, version: 1060
input: Goodix Capacitive TouchScreen as .../i2c-3/3-0014/input/input0

/dev/input/event0 is created and held open by warden-ui (pid 517, exclusive EVIOCGRAB — which is why a second reader sees 0 bytes; the events go to the UI).

Root cause on _b

Touch was dead on _b while fine on _a. dmesg showed:

module goodix: .gnu.linkonce.this_module section size must match the kernel's
built struct module size at run time

The stock rootfs ships goodix.ko built for the 5.10 kernel; it cannot load on our 6.18 (struct module layout mismatch). Our 6.18 .config did not have the driver at all (# CONFIG_TOUCHSCREEN_GOODIX is not set), and the DTS had no GT911 node — so nothing drove the GT911.

Fix

  1. CONFIG_TOUCHSCREEN_GOODIX=y — build the mainline Goodix driver into the kernel (no module → no vermagic/struct mismatch; the stale rootfs .ko still fails to insmod but is now harmless).
  2. GT911 DT node under &i2c3 (matches the vendor 86-panel wiring):
    touchscreen@14 {
        compatible = "goodix,gt911";
        reg = <0x14>;
        interrupt-parent = <&gpio0>;
        interrupts = <RK_PA0 IRQ_TYPE_EDGE_FALLING>;
        irq-gpios   = <&gpio0 RK_PA0 GPIO_ACTIVE_HIGH>;
        reset-gpios = <&gpio3 RK_PD0 GPIO_ACTIVE_HIGH>;
    };
    
    plus pinctrl-0 = <&i2c3m2_xfer &tp_rst &tp_irq> on &i2c3 and the tp_rst (GPIO3_D0) / tp_irq (GPIO0_A0) pin groups.

Polarity note: mainline goodix drives reset logical 0 = hold, 1 = release, and the GT911 reset is physically active-low, so reset-gpios is ACTIVE_HIGH (logical==physical) — NOT the ACTIVE_LOW the vendor 5.10 driver used. Confirmed against mainline gt911 DT examples (sun7i-a20-wexler-tab7200 etc.): both irq-gpios and reset-gpios are ACTIVE_HIGH; reg 0x14 needs irq-gpios for address select.

Non-fatal: Direct firmware load for goodix_911_cfg.bin failed (-2) — the GT911 uses its flashed internal config; touch works without a cfg.bin.

Files changed (research/linux-6.18.46)

  • .configCONFIG_TOUCHSCREEN_GOODIX=y.
  • arch/arm/boot/dts/rockchip/rv1106-warden.dts — GT911 node on &i2c3, tp_rst/tp_irq pin groups under &pinctrl.