[EnygmaINC]

Summary

Adds support for the 3.5" ESP32-S3 320x480 touch module sold as the LCDwiki
ES3C35P (also rebadged, e.g. Hosyond "ESP32-S3 Touchscreen Module 3.5"" and
AliExpress "cheap black display" listings). Requested in #434. Depends on bmorcelli/DisplayDrivers#3 (the display driver).

This panel is not covered by any existing databus: the ST77922 is driven over
quad-SPI with no DC pin, and wants register writes on one line but pixel
data on four. Arduino_GFX's Arduino_ESP32QSPI sends every phase on four
lines, so it cannot drive the panel. The change adds:

1. Display -- Arduino_ST77922_1L4 (TFT_DATABUS_N=6, TFT_DISPLAY_DRIVER_N=52),
   an own-bus raw ESP-IDF spi_master driver. Lives in the DisplayDrivers
   submodule (separate PR, linked below). USE_CANVAS=1 handles rotation in
   software, since this panel's MADCTL does not remap addressing.
2. Touch -- new TOUCH_CTRL_ST77922 branch in src/hal/inputs/touch.cpp.
   The touch block is built into the same IC (I2C 0x55, 16-bit big-endian
   register addresses). It is not FT6x36-compatible, despite appearing as
   "FT6336G-compatible" in some third-party notes; the FT6X36 path reads the
   wrong registers on this chip.
3. Board -- boards/lcdwiki-es3c35p/ (platformio.ini, interface.cpp,
   connections.md), registered in the CI matrix; default_envs entry added
   commented-out like every other board.

Nothing in src/ outside touch.cpp is changed, and the touch.cpp addition
is entirely behind TOUCH_CTRL_ST77922.

Hardware / links

Vendor page	https://www.lcdwiki.com/3.5inch_ESP32-S3_Display
AliExpress listing (unit tested)	https://www.aliexpress.us/item/3256812149380399.html (submitter confirmed this is the listing the unit came from)
Amazon rebadge	Hosyond "ESP32-S3 Touchscreen Module 3.5"", ASIN B0H28X8SQ4 (taken from community docs; not purchased or verified by the submitter)
Vendor example code	https://github.com/ydedox/st77922 (Example_01 = display, Example_08 = touch)
Related prior art	78/xiaozhi-esp32 boards/lcdwiki-es3c35p/; https://tinkerpad.co.uk/esp32-s3-35-lcd.html
Request	#434

Pinout (all documented in boards/lcdwiki-es3c35p/connections.md):
display CS=10 SCLK=12 D0=11 D1=13 D2=14 D3=9 BL=41 (no RST pin);
touch SDA=38 SCL=39 RST=48 INT=47; SD native 4-bit SDIO CLK=5 CMD=4 D0=6 D1=7 D2=2 D3=3;
battery sense GPIO 8; WS2812 on 40; BOOT=0.

Pitfalls worth a reviewer's attention

• TFT_DC=-1 / TFT_IPS=0 in the board ini are load-bearing.
  include/pre_compiler.h's "CYD defaults" block silently redefines
  TFT_CS/TFT_SCLK (to 15/14) whenever a board defines none of TFT_DC,
  TFT_IPS, TFT_COL_OFS* or TFT_MOSI. A QSPI board has no DC or MOSI pin,
  so without these two flags the SPI bus init fails ("not using iomux pins").
  This cost most of the bring-up time; it may be worth a comment or a different
  guard in pre_compiler.h as a follow-up (not changed here).
• Touch must read the whole report block in one transfer (maxTouches * 8
  bytes). Reading only the first record leaves the controller returning a
  stale point forever.
• GPIO48 (touch reset) idles low; the touch half does not answer on I2C until
  it is pulsed (done once in _setup_gpio()). The display does not need it.
• powerOff(): touch cannot wake deep sleep here (INT is GPIO47, not an RTC
  pad), so BOOT/GPIO0 (ext0) is the only wake source. The board's powerOff()
  enables it, switches the backlight off and latches the pin low for the sleep,
  and _setup_gpio() releases the latch on boot.

Verification

Tested on one physical unit (AliExpress purchase above) running the image built
from this branch, flashed with esptool at 0x0 (merged image).

Build: pio run -e lcdwiki-es3c35p succeeds on this branch rebased onto
current main (the full test matrix below was run on the same code before
rebasing onto two unrelated upstream Heltec commits; after the rebase the board
was reflashed and re-checked for boot, touch and brightness). Firmware app
image is about 1.42 MB (8.5 % of the 16 MB flash); RAM use 26.4 %.

Area	Result	How
Display, orientation, colour order	Pass	on device
Backlight PWM / brightness setting	Pass	on device (menu setting changes brightness; re-checked on the final build)
Touch: menu navigation	Pass	on device
Touch: on-screen keyboard (Wi-Fi password entry)	Pass	on device
SD card (4-bit SDIO)	Pass	on device
Rotation 0 / 1 / 2 / 3, display and touch	Pass	Rotation menu, on device
Battery sense (GPIO 8, 1:2 divider)	Pass	ADC 2.007 V x 2 = 4.01 V vs 3.99-4.00 V on a multimeter while charging; 3.90 V on battery shows 73 %; charging shows 88 % with the charging icon
Turn-off / deep sleep	Pass	screen fully dark; BOOT wakes; touch does not wake (expected)
Launching firmware from SD	Pass	two ESP32-S3 images installed from the SD file browser and booted: (a) this branch's own app image, and (b) the official 78/xiaozhi-esp32 v2.5.2 lcdwiki-es3c35p merged image (10.2 MB, SHA-256 matched the release's SHA256SUMS)
Wrong-chip image is rejected	Pass	a classic-ESP32 image (header chip id 0x0000) fails the install check with "Flash Read Failed" instead of being booted -- expected behaviour, not a port issue
Reboot from menu	Pass	on device

Observed once, not reproduced: a single episode of touch moving 1-2 menu
entries too far per tap during a long test session (USB plus charging LiPo).
It cleared after a full power cycle (battery and USB removed) and has not
recurred; cause unknown, possibly transient electrical noise while charging.

Observed, not specific to this board: uploading a 10 MB file through the
Launcher web file manager failed with Upload failed: Upload receive failed
(the receive loop got a dropped connection mid-body; serial log shows no panic,
watchdog or reboot). A ~1 MB upload through the same path succeeded. The SD
card, flash and image checks were never reached. Copying the file onto the SD
card directly avoids the web path.

Not tested: deep sleep on battery alone with USB removed; sleep current;
audio (the ES8311 codec / SC8002B amp are only held quiet -- Launcher has no
sound output on any board); only a single hardware unit.

Regression check on shared code: touch.cpp and DisplayDrivers are shared, so
ES3C28P and ES3C40P (same family, standard-SPI panels sharing the touch and
DisplayDrivers code) were also built from this branch: both pio run builds
succeed. These were build checks only; they were not flashed or run.

Merge order

1. Merge Add Arduino_ST77922_1L4: QSPI ST77922 driver (id 52, bus 6) DisplayDrivers#3 (adds Arduino_ST77922_1L4 and the bus-6 wiring).
2. This PR then bumps the lib/DisplayDrivers submodule pointer to that commit.
   Until step 1 lands, CI on this PR cannot fetch the submodule commit.
   If the DisplayDrivers PR is squash-merged, its commit hash changes, so the
   submodule pointer here needs updating to the merged hash before this merges.
   This PR is therefore opened as a draft until then.

Provenance / licensing note

The ST77922 init-command table is the one from the board vendor's published
example (https://github.com/ydedox/st77922, Example_01), which carries no
license file. It is register data rather than code, and confirmed working on
hardware, but flagging it so the maintainer can decide whether they are
comfortable with it or want it sourced from the MIT-licensed
78/xiaozhi-esp32 equivalent instead. All other code is original to this PR.

Another contributor (@javaoverride, in #434) has independently got this board
working with a different approach (Arduino_GFX driver files and submodule edits).
This PR does not use their code; happy to coordinate or merge efforts.

Closes #434

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