Waveshare ESP32-P4-NANO + 10.1-DSI-TOUCH-A (800×1280, JD9365 + GT9271) — the two-piece combination

The Waveshare ESP32-P4-NANO carrier with a 10.1-DSI-TOUCH-A panel plugged into the MIPI-DSI FPC. This is the two-piece combination, not the all-in-one ESP32-P4-WIFI6-Touch-LCD-10.1 that has already shipped as the waveshare101 board. Same glass and the same esp32p4-c6.yaml wiring, but the two carriers differ in the places that matter: the all-in-one routes an LCD reset pin and a backlight PWM pin, and this one routes neither.

** Hardware:** ESP32-P4 (module ESP32-P4NRW32), chip revision v1.3, 2 cores at 360 MHz. The P4 has no radio of its own, so an ESP32-C6 beside it does Wi-Fi 6 over a four-bit SDIO bus. 32 MB of in-package PSRAM in hex mode at 200 MHz, and 16 MB of NOR flash (some batches of the module ship 32 MB). Panel: JD9365, 800x1280, 10.1 inch, two DSI lanes at 1.5 Gbps, 149 dpi. Touch: GT9271, GT911-compatible, and polled, because neither its interrupt nor its reset is wired to the P4.

** What makes this board different:** The panel has no reset GPIO and no backlight PWM GPIO. It is enabled over I2C instead, by writing 0x11 and then 0x17 to register 0x95 of I2C device 0x45, and it is dimmed through register 0x96 of the same controller. Waveshare do that enable inside esp_lcd_new_panel_jd9365(), before any DSI traffic. ESPHome's mipi_dsi never writes 0x95, so without it the panel never drives its side of the link: the DSI command FIFO fills after about 19 commands and never drains, and the task watchdog aborts the boot ten times over into safe mode with a dark screen. Reported upstream as esphome/esphome#21451.

One board file covers three carriers: the ESP32-P4-NANO, the ESP32-P4-Module-DEV-KIT and the ESP32-P4-WIFI6-DEV-KIT are wired the same for the display, the touch bus and this enable. ESPHome names the panel after the Nano, model: WAVESHARE-P4-NANO-10.1, which is what the board is called here.