fix(web): accept every panel size and row address type the rgbmatrix library does (#586)

* fix(web): accept every panel size and row address type the rgbmatrix library does

The Display form capped columns at 128 and chain length at 24, and its
submit handler (fixInvalidNumberInputs) rewrote anything larger to the cap,
so wide panels and long chains silently saved as the wrong size. The config
API checked none of the hardware numbers, so values the library rejects (odd
rows, parallel 4, PWM dither bits 3) saved and the matrix then refused to
start.

- Form limits now match the pinned library: rows even 8-64, cols >= 16 and
  chain_length >= 1 with no upper bound, parallel 1-3, PWM dither bits 0-2,
  PWM LSB nanoseconds 50-3000.
- save_main_config rejects out-of-range rows, cols, chain_length, parallel,
  brightness, scan_mode, pwm_bits, pwm_dither_bits, pwm_lsb_nanoseconds and
  gpio_slowdown with a 400.
- A stored gpio_slowdown or pwm_dither_bits of 0 renders as 0 instead of the
  default, so saving the tab no longer overwrites it.
- Row Address Type offers 5 (SM5368 / B707 row shift register). Verified on a
  Waveshare 96x48 V2 (24S-A1) on a Pi 4 with the Adafruit Triple LED Matrix
  Bonnet: rows 48, cols 96, row address type 5, BGR, GPIO slowdown 8.
- Help text and docs: FM6124-family panels use Panel Type Standard; on a Pi 5
  the library supports only row address types 0 and 2.

No change to the rpi-rgb-led-matrix submodule.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* fix(web): drop the rows cap and document every display setting accurately

Rows: no upper limit in the form or the API. Still even and at least 8. The
current rgbmatrix library rejects more than 64 per panel, so a larger value
saves but the matrix won't start; the help tip, README, config reference and
troubleshooting section all say so, and nothing here needs changing if the
library lifts the limit.

limit_refresh_rate_hz: the form accepts 0 (the library's "no cap"), a stored
0 no longer renders and re-saves as 120, and the API rejects negatives.

pwm_dither_bits stays 0-2: the library rejects 3 and 4, so the old form's
0-4 only ever let users save a config the display couldn't start with.

Docs and help tips, checked against the pinned library and its README:
- panel_type and rp1_rio get README entries
- show_refresh_rate prints to stdout; it never drew on the panel
- dither bits raise the refresh rate; the tip said they lowered it
- scan_mode is about interlacing at low refresh, not wrong colours
- disable_hardware_pulsing: hardware pulsing needs OE on GPIO 18 and the
  onboard sound driver off; software timing makes rows flash brighter
- gpio_slowdown guidance agrees between the README and the UI
- all 22 multiplexing values listed; every numeric setting states its range
- troubleshooting for a blank panel after a settings change, jumping rows
  and brightness flashes

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* fix(web): reject true and 5.5 for row_address_type and multiplexing

Both still went straight through int(), so a JSON true saved as 1 and 5.5
as 5. They now use the shared hardware range check like the other panel
fields. Review feedback on #586.

Also: the RP1 Backend tooltip said it is ignored on Pi 3/4 (it is ignored
on every model but the Pi 5), and the README gave the dynamic-duration
default cap as 90s; the code default is 180s.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* feat: refuse matrix settings a Raspberry Pi 5 can't drive

On a Pi 5 the pinned rgbmatrix library drives the panel through the RP1
chip, and that path supports only row address types 0 and 2, parallel 1-3
and the regular / regular-pi1 / classic / adafruit-hat(-pwm) mappings
(Rp1PioConfigSupported in lib/rp1/rp1_pio_backend.cc). For anything else
CreateFromOptions returns NULL; the Python binding doesn't check, so the
display process crashed on its first call into the matrix and systemd
restarted it into the same crash every 10 seconds.

- src/pi5_matrix_support.py: the rule and Pi 5 detection, matching the
  library's /proc/device-tree/model check
- DisplayManager raises before creating the matrix, so it is a logged init
  failure (reported by /api/v3/hardware/status) and fallback mode
- the config API rejects those settings on a Pi 5 when a request sets
  row_address_type, parallel or hardware_mapping
- the Display form offers only row address types 0 and 2 on a Pi 5, and
  warns when a stored value can't be used
- CLAUDE.md: re-check the rule whenever the submodule is bumped

Review feedback on #586.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

docs/CONFIG_REFERENCE.md

@@ -51,25 +51,25 @@ in `DisplayManager` (`src/display_manager.py`, ~lines 270–295).
 
 | Key | Type / default |
 |---|---|
-| `rows` / `cols` | int, `32` / `64` |
-| `chain_length` | int, `2` |
-| `parallel` | int, `1` |
-| `brightness` | int, `90` |
+| `rows` / `cols` | int, `32` / `64` — rows: even, at least 8, no upper limit here (the current rgbmatrix library rejects more than 64); cols: at least 16, no upper limit |
+| `chain_length` | int, `2` — at least 1, no upper limit |
+| `parallel` | int, `1` — 1–3 |
+| `brightness` | int, `90` — 1–100 |
 | `hardware_mapping` | string, `"adafruit-hat"` (code default `"adafruit-hat-pwm"`) |
-| `scan_mode` | int, `0` |
-| `pwm_bits` | int, `9` (code default 10) |
-| `pwm_dither_bits` | int, `1` |
-| `pwm_lsb_nanoseconds` | int, `130` (code default 150) |
-| `disable_hardware_pulsing` | bool, `false` |
+| `scan_mode` | int, `0` — `0` progressive, `1` interlaced |
+| `pwm_bits` | int, `9` (code default 10) — 1–11 |
+| `pwm_dither_bits` | int, `1` — 0–2 |
+| `pwm_lsb_nanoseconds` | int, `130` (code default 150) — 50–3000 |
+| `disable_hardware_pulsing` | bool, `false` — `true` times brightness pulses in software (less exact); hardware pulsing needs the OE line on GPIO 18 and the Pi's onboard sound driver off |
 | `inverse_colors` | bool, `false` |
-| `show_refresh_rate` | bool, `false` |
-| `led_rgb_sequence` | string, `"RGB"` |
-| `limit_refresh_rate_hz` | int, `100` (code default 90) |
+| `show_refresh_rate` | bool, `false` — prints the refresh rate to stdout; draws nothing on the panel |
+| `led_rgb_sequence` | string, `"RGB"` — `"RGB"`, `"RBG"`, `"GRB"`, `"GBR"`, `"BRG"` or `"BGR"` |
+| `limit_refresh_rate_hz` | int, `100` (code default 90) — `0` = no cap; scroll timing assumes 100 Hz when `0` |
 | `pixel_mapper_config` | string, `""` — e.g. `"U-mapper"` / `"Rotate:90"` |
 | `orientation` | string, `"normal"` — `"180"` rotates the rendered image 180° for panels physically mounted upside down (e.g. to move the Pi/wiring to a more convenient side); composed onto `pixel_mapper_config` as a trailing `Rotate:180` mapper, so it stays independent of any custom `pixel_mapper_config` value |
-| `row_address_type` | int, `0` — non-standard panel row addressing |
-| `multiplexing` | int, `0` — panel multiplexing scheme |
-| `panel_type` | string, `""` — set to `"FM6126A"` or `"FM6127"` for panels needing init |
+| `row_address_type` | int, `0` — non-standard panel row addressing: `1` AB, `2` direct row select, `3` ABC, `4` ABC shift + DE direct, `5` SM5368 / B707 row shift register (e.g. Waveshare 96x48 V2, with `led_rgb_sequence` `"BGR"`). On a Pi 5 the library supports only `0` and `2`, and LEDMatrix enforces that (`src/pi5_matrix_support.py`) |
+| `multiplexing` | int, `0` — 0–22, pixel wiring scheme for outdoor/specialty panels (names listed in the README) |
+| `panel_type` | string, `""` — set to `"FM6126A"` or `"FM6127"` for panels needing init; FM6124 / FM6124D / FM6124DJ panels need none, so leave it `""` |
 
 Where "code default" differs from the template value, the code default only
 applies if the key is missing entirely from your config.
@@ -78,8 +78,8 @@ applies if the key is missing entirely from your config.
 
 | Key | Type / default | Meaning |
 |---|---|---|
-| `gpio_slowdown` | int, `3` | GPIO timing slowdown for faster Pis |
-| `rp1_rio` | int, `0` | RP1 RIO mode on Pi 5 (applied only if the installed matrix library supports it) |
+| `gpio_slowdown` | int, `3` | GPIO timing slowdown for faster Pis (0–10). Panels on `row_address_type` `5` (SM5368 row drivers) can need 6–8 on a Pi 4 — lower values make rows jump |
+| `rp1_rio` | int, `0` | Pi 5 only: `0` = PIO (less CPU), `1` = RIO (higher refresh; `gpio_slowdown` effect inverted). Applied only if the installed matrix library supports it |
 
 ## `display.double_sided`
 

docs/GETTING_STARTED.md

@@ -83,10 +83,10 @@ You should see:
 
 1. Open the **Display** tab
 2. Set your matrix configuration:
-   - **Rows**: 32 or 64 (match your hardware)
-   - **Columns**: commonly 64 or 96; the web UI accepts any integer
-     in the 1–128 range, but 64 and 96 are the values the bundled
-     panel hardware ships with
+   - **Rows**: match your panel — commonly 32 or 64; any even number
+     from 8 to 64
+   - **Columns**: match your panel — commonly 64 or 96; at least 16,
+     with no upper limit
    - **Chain Length**: Number of panels chained horizontally
    - **Hardware Mapping**: usually `adafruit-hat-pwm` (with the PWM jumper
      mod) or `adafruit-hat` (without). See the root README for the full list.

docs/WEB_INTERFACE_GUIDE.md

@@ -132,18 +132,26 @@ require a display service restart from **Overview**.
 Configure your LED matrix hardware:
 
 **Matrix configuration:**
-- `rows` — LED rows (typically 32 or 64)
-- `cols` — LED columns (typically 64 or 96)
+- `rows` — LED rows per panel (typically 32 or 64; even, at least 8 — the
+  current rgbmatrix library rejects more than 64)
+- `cols` — LED columns per panel (typically 64 or 96; at least 16)
 - `chain_length` — number of horizontally chained panels
-- `parallel` — number of parallel chains
+- `parallel` — number of parallel chains (1–3)
 - `hardware_mapping` — `adafruit-hat-pwm` (with PWM jumper mod),
-  `adafruit-hat` (without), `regular`, or `regular-pi1`
-- `gpio_slowdown` — must match your Pi model (3 for Pi 3, 4 for Pi 4, etc.)
-- `brightness` — 0–100%
+  `adafruit-hat` (without), `regular` (direct wiring, and the Adafruit Triple
+  LED Matrix Bonnet), or `regular-pi1`
+- `gpio_slowdown` — depends on your Pi and panel (roughly 1–3 on a Pi 3,
+  2–4 on a Pi 4); raise it if rows jump or the image is garbage
+- `brightness` — 1–100%
 - `pwm_bits`, `pwm_lsb_nanoseconds`, `pwm_dither_bits` — PWM tuning
 - Dynamic Duration — global cap for plugins that extend their display
   time based on content
 
+The collapsed **Advanced Hardware & Display Options** section holds
+multiplexing, panel type, row address type, scan mode, PWM tuning, the
+refresh-rate cap and hardware pulsing. Every field has a help tip, and the
+README's Display Settings section describes each one with its allowed range.
+
 **Vegas Scroll Mode:** the Display tab also has a full Vegas Scroll
 Mode section — enable toggle, scroll speed, separator width, dynamic
 duration, and related settings — so you can configure Vegas mode