STRUCT HX8279_DIGITAL_GAMMA(9)

👑 NAME 👑

struct hx8279_digital_gamma — Digital Gamma Adjustment ✨ (it's a Linux kernel API page, bestie, from the struct hx8279_digital_gamma(9) manual 💅)

✨ SYNOPSIS ✨

okay so here's the actual struct, no cap, copied exactly:

struct hx8279_digital_gamma {
    u8 r[HX8279_PG_DGAMMA_NUM_LO_BYTES + HX8279_PG_DGAMMA_NUM_HI_BYTES];
    u8 g[HX8279_PG_DGAMMA_NUM_LO_BYTES + HX8279_PG_DGAMMA_NUM_HI_BYTES];
    u8 b[HX8279_PG_DGAMMA_NUM_LO_BYTES + HX8279_PG_DGAMMA_NUM_HI_BYTES];
 };

🎀 Members 🎀

• r — the adjustment for the red component 💄
• g — the adjustment for the green component 🍓
• b — the adjustment for the blue component 🦋

💜 Description 💜

So the tea is: the layout of this struct literally follows the register layout, and that's on purpose — it makes both the handling and the declaration of those values in the driver way simpler. Iconic design choice, honestly. 👑

Gamma correction is internally done with a 24 segment piecewise linear interpolation, and those segments are defined with 24 ten bits values, of which:

• The LOW eight bits for the first 24 registers start at the first register (at 0xb1) of the Digital Gamma Adjustment page 📄
• The HIGH two bits for each of the 24 registers are contained in the last six registers 🔥
• The last six registers contain four groups of two-bits HI values for each of the first 24 registers, but in an inverted fashion — this means that the first two bits relate to the last register of a set of four 🙈 (yes, it's giving chaotic but that's the layout, iykyk)

And periodt, the 24 segments refer to these gamma levels ⤵️

0, 1, 3, 7, 11, 15, 23, 31, 47, 63, 95, 127, 128, 160, 192, 208, 224, 232, 240, 244, 248, 252, 254, 255

🦋 SEE ALSO 🦋

Go look at the kernel file ./drivers/gpu/drm/panel/panel-himax-hx8279.c, plus struct hx8279_goa_mux(9) and struct hx8279_analog_gamma(9) 🫶

okay that's the whole page, you ate that 💅 mwah! this gem lives over in ./drivers/gpu/drm/panel, it's dated October 2026, and it's filed under struct hx8279_digital_gamma(9) 🌸🎀