STRUCT CHARLCD_OPS(9)

💖 struct charlcd_ops(9) 💖

okay bestie, so this is a page from the Kernel API Manual, and it's all about struct charlcd_ops — the icon ✨

🌸 NAME 🌸

struct charlcd_ops — the functions used by charlcd. Drivers have to implement these. no cap, it's literally their whole job 🫶

🎀 SYNOPSIS 🎀

struct charlcd_ops {
    void (*backlight)(struct charlcd *lcd, enum charlcd_onoff on);
    int (*print)(struct charlcd *lcd, int c);
    int (*gotoxy)(struct charlcd *lcd, unsigned int x, unsigned int y);
    int (*home)(struct charlcd *lcd);
    int (*clear_display)(struct charlcd *lcd);
    int (*init_display)(struct charlcd *lcd);
    int (*shift_cursor)(struct charlcd *lcd, enum charlcd_shift_dir
dir);
    int (*shift_display)(struct charlcd *lcd, enum charlcd_shift_dir
dir);
    int (*display)(struct charlcd *lcd, enum charlcd_onoff on);
    int (*cursor)(struct charlcd *lcd, enum charlcd_onoff on);
    int (*blink)(struct charlcd *lcd, enum charlcd_onoff on);
    int (*fontsize)(struct charlcd *lcd, enum charlcd_fontsize size);
    int (*lines)(struct charlcd *lcd, enum charlcd_lines lines);
    int (*redefine_char)(struct charlcd *lcd, char *esc);
};

like, that's the whole squad right there 👑

🦋 Members 🦋

• backlight — turn the backlight on or off. lowkey optional, so nobody's forcing you 💅
• print — print one character to the display at the current cursor position. the buffered cursor position gets advanced by charlcd. and listen: the cursor should not wrap to the next line at the end of a line. not me warning you in advance 😭
• gotoxy — set the cursor to x, y. the x and y values you're setting are previously set in addr.x and addr.y by charlcd, so they're already served up for you 🍓
• home — set the cursor to 0, 0. the values in addr.x and addr.y are set to 0, 0 by charlcd prior to calling this function. home sweet home ✨
• clear_display — clear the whole display and set the cursor to 0, 0. the values in addr.x and addr.y are set to 0, 0 by charlcd after calling this function (yes, after — read it twice, i did 🙈)
• init_display — initialize the display. main character energy, honestly 💜
• shift_cursor — shift the cursor left or right one position 🌈
• shift_display — shift the whole display content left or right. the entire vibe, moving 🔥
• display — turn the display on or off.
• cursor — turn the cursor on or off.
• blink — turn cursor blink on or off. iconic.
• lines — one or two lines. that's it, that's the whole thing 🤏
• redefine_char — redefine the actual pixel matrix of the character. like a glow-up but for pixels 🧚

ngl bestie, fontsize shows up in the struct up there but it doesn't get its own little entry in this list — so don't come for me, i'm just telling you what the page says 💀

⭐ SEE ALSO ⭐

• Kernel file ./drivers/auxdisplay/charlcd.h — go read it, iykyk 📖

kisses and bye-bye bestie 🫶💖 this slay little page lives in ./drivers/auxdisplay, dated October 2026, and it goes by struct charlcd_ops(9) — periodt. 💅🎀