wrpll_calc_output_rate(9)

💅 wrpll_calc_output_rate — the kernel API manual, but make it make sense

okay so bestie, this is wrpll_calc_output_rate from the Kernel API Manual. yes it's a mouthful, no you don't have to say it out loud. it's a function, it does math, and honestly? it ate. 🎀

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✨ NAME ✨

wrpll_calc_output_rate — literally just calculating the PLL's target output rate. that's it. that's the whole gig. 💖

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🦋 SYNOPSIS 🦋

unsigned long wrpll_calc_output_rate (const struct wrpll_cfg *c ,
unsigned long parent_rate );

not me writing unsigned long twice in one signature 😭 anyway. it returns an unsigned long and it takes these two things:

• c — a const struct wrpll_cfg *, i.e. a pointer to the config record
• parent_rate — an unsigned long, the PLL refclk rate

periodt. 💅

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🌸 ARGUMENTS 🌸

• c — ptr to a struct wrpll_cfg record to read from. it's const, so we're reading, not touching. respectful king behavior tbh 🫶
• parent_rate — the PLL refclk rate. the reference clock. the blueprint. the main character of the input side 🔥

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👑 DESCRIPTION 👑

so here's the vibe check: you hand this function a pointer to the PLL's current input configuration c, plus the PLL's input reference clock rate parent_rate — and important detail, that's the rate before the R pre-divider, bestie, don't forget the pre-divider 💀

then it calculates the PLL's output clock rate — and that's the one after the Q post-divider. so: pre-divider in, post-divider out. the glow-up is real. ✨

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💜 CONTEXT 💜

Any context. no restrictions, she's flexible, she's versatile 🧚

⚠️ but the caller must protect the memory pointed to by c from simultaneous modification. that's on YOU, not on the function. no cap. 🙈

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⭐ RETURN ⭐

it returns the PLL's output clock rate, in Hz. 🎀

and like — the return value from this function is intended to be convenient to pass directly to the Linux clock framework. so convenient, so slay. which means: there is no explicit error return value. no -EINVAL, no little sad error code, nothing. it just hands you a number and trusts you. 💖

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/clk/analogbits/wrpll-cln28hpc.c — go read the source, iykyk 👀
• __wrpll_calc_filter_range(9)
• __wrpll_calc_fbdiv(9)
• __wrpll_calc_divq(9)
• __wrpll_update_parent_rate(9)
• wrpll_configure_for_rate(9)
• wrpll_calc_max_lock_us(9)

the whole friend group fr fr 🫶

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and that's the page!! mwah 💋 this one lives in ./drivers/clk/analogbits and it's dated October 2026 — so yeah, she's from the future, iconic behavior honestly 👑✨🌸