rzv2h_icu_register_dma_ack(9)

💖 rzv2h_icu_register_dma_ack 💖

okay so you're reading the Kernel API Manual page for rzv2h_icu_register_dma_ack, and honestly? she's a little baddie whose whole job is routing DMA ACK signals. no cap. let's get into it 🎀

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✨ NAME ✨

rzv2h_icu_register_dma_ack — configure DMA ACK signal routing. that's it, that's the vibe. 💅

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🌸 SYNOPSIS 🌸

void rzv2h_icu_register_dma_ack (struct platform_device *icu_dev , u8 dmac_index , u8 dmac_channel , u16 ack_no );

like, four args, one function, zero drama (well… mostly). 🦋

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🫶 ARGUMENTS 🫶

• icu_dev — the ICU platform device. your main character struct, literally the whole reason we're here. ✨
• dmac_index — DMAC instance index, and it lives in the range (0-4). yes bestie, five whole instances. choose wisely. 🔥
• dmac_channel — DMAC channel number, (0-15). OR — and this is the fun part — you can pass RZV2H_ICU_DMAC_ACK_NO_DEFAULT to disconnect the routing for a given ack_no. it's giving "unsubscribe" energy 💀
• ack_no — peripheral ACK number, (0-88) per RZ/G3E manual Table 4.6-28, and it's used as the index into ICU_DMACKSELk. so like, it's not just a number, it's a lookup key, iykyk 👑

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💜 DESCRIPTION 💜

so what does she actually do?? she routes the ACK signal of the peripheral identified by ack_no to DMAC channel dmac_channel of instance dmac_index. simple. iconic. slay. 🌈

and when dmac_channel is RZV2H_ICU_DMAC_ACK_NO_DEFAULT, the field gets reset, which disconnects any previously configured routing for that peripheral. so it's not just "do nothing" — it actively clears the old route. periodt. 🧚

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⭐ SEE ALSO ⭐

• Kernel file ./drivers/irqchip/irq-renesas-rzv2h.c
• struct rzv2h_irqc_reg_cache(9)
• struct rzv2h_hw_info(9)
• struct rzv2h_icu_priv(9)

go read those structs, bestie, they're the supporting cast and they ate. 👑💖

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ngl this one's short and sweet — but don't sleep on the disconnect behaviour, fr fr. passing RZV2H_ICU_DMAC_ACK_NO_DEFAULT is a whole reset, not a no-op. 🙈

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okay that's the page!! source/version is ./drivers/irqchip, dated October 2026, and it's all from the Kernel API Manual. mwah, go route some ACK signals, you got this 🍓💜✨