BFE EngineeringandClaude Opus 4.8
189f7aec38
- 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
58 lines
2.4 KiB
Markdown
58 lines
2.4 KiB
Markdown
# 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)
|
|
|
|
- `.config` — `CONFIG_TOUCHSCREEN_GOODIX=y`.
|
|
- `arch/arm/boot/dts/rockchip/rv1106-warden.dts` — GT911 node on `&i2c3`,
|
|
`tp_rst`/`tp_irq` pin groups under `&pinctrl`.
|