esp_lcd: panel_io_i80_tx_color without cmd (IDFGH-9426)

[mcbp223]

Is your feature request related to a problem?

This is the same request as in #10302 and #9881, but for the i80 bus instead of SPI.
For panel_io_i80_tx_param and panel_io_i80_tx_color don't send cmd if the parameter is negative.

I have tried in lcd_start_transaction(...) with

    uint32_t cmd_cycles = trans_desc->cmd_cycles;
    if (trans_desc->cmd_value < 0) {
        cmd_cycles = 0;
    } else {
        lcd_ll_set_command(bus->hal.dev, bus->bus_width, trans_desc->cmd_value);
    }
    lcd_ll_set_phase_cycles(bus->hal.dev, cmd_cycles, 0, trans_desc->data ? 1 : 0);

It does skip the command, but there seems to appear a moirée pattern over the image, like a regular grid of dots, or vertical lines that appear like xor, or data bus not ready for a pixel, maybe some timing is off, so it would need some more testing. The geometry of the image stays correct.

Describe the solution you'd like.

No response

Describe alternatives you've considered.

No response

Additional context.

No response