nal_hevc_write_sps(9)

💅 nal_hevc_write_sps(9) 💅

okay so bestie, welcome to the Kernel API Manual, section 9 🎀 — this is the little function that takes your SPS and makes it RBSP. Ngl it's giving "small function, big job" energy and we're obsessed ✨

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🌸 NAME 🌸

nal_hevc_write_sps — literally writes an SPS NAL unit into RBSP format 💖 that's it, that's the whole vibe.

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✨ SYNOPSIS ✨

ssize_t nal_hevc_write_sps (const struct device *dev , void *dest ,
       size_t n , struct nal_hevc_sps *sps );

look at her 😭 so clean, so iconic, so many arguments. let's go through them one by one, no skipping, i promise 🫶

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🦋 ARGUMENTS 🦋

• dev — the device pointer. yeah, that one. the device bestie 💅
• dest — the buffer that gets filled with RBSP data 🎀 this is the glow-up location, where the data goes to become beautiful
• n — the maximum size of dest, in bytes. it's the vibe check on how much room dest actually has 🔥
• sps — the struct nal_hevc_sps we're converting to RBSP. the main character of this whole operation 👑

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💜 DESCRIPTION 💜

so what does she do? she converts sps to RBSP data and writes it right into dest ✨ that's the whole gig, and she does it flawlessly.

but — and this is the important part, don't scroll past it — the size of the SPS NAL unit is not known in advance 🙈 so there's no cute little pre-flight check you can do beforehand. and this function will fail if dest does not hold sufficient space for the SPS NAL unit 💀 like, she's not gonna squeeze it in, she's not gonna improvise, she's just gonna fail. so pls, pls, pls give her enough room 🙏

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🌈 RETURN 🌈

she returns the number of bytes written to dest 🎉 (slay) — or a negative error code 😭 if things didn't work out. check it! always check it! periodt 💅

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👑 SEE ALSO 👑

• the kernel file: ./drivers/media/platform/allegro-dvt/nal-hevc.c 📁 (the whole squad lives here)
• nal_hevc_write_vps(9) — the VPS-writing bestie
• nal_hevc_read_vps(9) — the VPS-reading bestie
• nal_hevc_read_sps(9) — the SPS-reading bestie (the mirror of this one, we stan a duo 🫶)
• nal_hevc_write_pps(9) — the PPS-writing bestie
• nal_hevc_read_pps(9) — the PPS-reading bestie
• nal_hevc_write_filler(9) — the filler-writing bestie
• nal_hevc_read_filler(9) — the filler-reading bestie

the whole friend group fr fr 🧚✨

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and that's the page!! 🎀 sign-off time: this one came from ./drivers/media/platform/alleg... and it's dated October 2026, filed under nal_hevc_write_sps(9) 💖 mwah, go write some RBSP, you got this 💅🌟