fsl_chan_toggle_ext_start(9)

✨ fsl_chan_toggle_ext_start(9) — the Kernel API Manual glow-up ✨

okay so bestie, we're in the Kernel API Manual today and the main character is fsl_chan_toggle_ext_start(9). she's a tiny function with one job and honestly? she ate. let's get into it 🎀

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🌸 NAME 🌸

fsl_chan_toggle_ext_start — flip the channel's external start status on or off, that's it, that's the whole vibe 💅

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✨ SYNOPSIS ✨

void fsl_chan_toggle_ext_start (struct fsldma_chan *chan , int enable );

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🦋 ARGUMENTS 🦋

• chan — the Freescale DMA channel in question, your little guy 🫶
• enable — 0 is disabled, 1 is enabled. binary queen, no in-between 👑

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💖 DESCRIPTION 💖

so here's the tea, fr fr: if you enable the external start, the channel can be kicked off by an external DMA start pin. which means dma_start does not start the transfer immediately — no ma'am, she waits. the channel literally just sits there, chilling, waiting for the control pin to be asserted before anything happens. main character energy: she does not move until the pin says so 💀✨

ngl this one's small but she matters — flip it wrong and your transfer timing does a whole different thing.

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🔥 SEE ALSO 🔥

the whole squad, and yes they're all listed, i'm not skipping a single one of them (iykyk) 🌈

Kernel file ./drivers/dma/fsldma.c and friends:

• fsl_chan_set_src_loop_size(9)
• fsl_chan_set_dst_loop_size(9)
• fsl_chan_set_request_count(9)
• fsl_chan_toggle_ext_pause(9)
• fsl_dma_free_descriptor(9)
• fsl_dma_alloc_descriptor(9)
• fsldma_clean_completed_descriptor(9)
• fsldma_run_tx_complete_actions(9)
• fsldma_clean_running_descriptor(9)
• fsl_chan_xfer_ld_queue(9)
• fsldma_cleanup_descriptors(9)
• fsl_dma_alloc_chan_resources(9)
• fsldma_free_desc_list(9)
• fsl_dma_free_chan_resources(9)
• fsl_dma_memcpy_issue_pending(9)
• fsl_tx_status(9)

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and that's the whole page bestie, go forth and toggle 🌸💜

signing off from the ./drivers/dma directory, dated October 2026 — mwah, fsl_chan_toggle_ext_start(9) out 🫶✨🎀