I’m looking at LCD_BL_EN and LCD_BL_PWM pins (GPIO_PH2 and PH1, respectively), and I’m wondering what is used to control them? is there a “driver” with some interface in /proc, or?
I plan to use these to control backlight of attached panel.
EN_AVDD_LCD, I guess can probably be controlled by writing to PMIC registers, otherwise it gets turned on at power-up and off during sleep/shutdown, correct? On the power sequencing diagram on page 3, it’s not exactly clear what happens with that signal - it seems to be always off.
EN_VDD_BL, What controls this one? Is it off in some power state? Do I need to care about it? It seems to be driven by DAP3_DOUT, which, after a quick look through TRM, I cannot find any mention of what it actually stands for (tho it looks like some kinda I2S-like thing based on the context). If this can be used to enable/disable my wled driver…
What does GPIO_PK2 do on expansion header? (I guess, nothing?)
What is LCD_TE? Is it “touch enable”? (my only guess lacking any other explanation).
I will use +VDD_MUX to power backlight, +3.3V_RUN to power tcon/panel electronics (should I gate it with en_avdd_lcd, or does it matter?).
LCD will be eDP, with 4 lanes in use.