dma_port_flash_update_auth(9)

💅 dma_port_flash_update_auth — the Kernel API Manual, but make it make sense

okay so bestie, you found the Thunderbolt DMA port flash-auth function in the Kernel API Manual and you're like "what does this even do" — don't worry, I got you. Sit down, hydrate, and let's get into it. 🫶

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✨ NAME ✨

dma_port_flash_update_auth — literally just starts the flash authenticate cycle. that's the whole vibe. 💫

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🌸 SYNOPSIS 🌸

int dma_port_flash_update_auth(struct tb_dma_port *dma);

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🎀 ARGUMENTS 🎀

• dma — the DMA control port. that's your main character right there, she's the one holding the struct.

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🦋 DESCRIPTION 🦋

Okay so here's the tea: this function starts the flash update authentication cycle. 🔥

If the image sitting in the non-active area was valid, the switch kicks off the upgrade process, and at the end of that whole journey the active and non-active areas get swapped. like a glow-up but for firmware, no cap. 💅

Now listen, because this is the important bit: the caller should call dma_port_flash_update_auth_status to get the status of this command. Why? Because if the switch in question is the root switch, the Thunderbolt host controller gets reset as well. 😭 so yeah, you're gonna want that status check, fr fr. it's not optional energy, it's "please check your status" energy.

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👑 RETURN 👑

0 on success, negative errno otherwise. bestie, if it's negative, it's not slaying, it's giving error. 🙈

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/thunderbolt/dma_port.c
• struct tb_dma_port(9)
• dma_port_alloc(9)
• dma_port_free(9)
• dma_port_flash_read(9)
• dma_port_flash_write(9)
• dma_port_flash_update_auth_status(9)
• dma_port_power_cycle(9)

the whole squad is in ./drivers/thunderbolt and honestly? iconic lineup. 🧚✨

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so yeah, that's the page. source is ./drivers/thunderbolt, dated October 2026, and you've officially been educated by the Kernel API Manual 💖 go forth and authenticate responsibly, mwah 💜🎀