_dma_no_cache_snooping(9)

✨ NAME ✨

okay so this is _dma_no_cache_snooping(9), straight outta the Kernel API Manual 💅

_dma_no_cache_snooping — and bestie, the original one-liner after the dash is literally blank, so I’m not gonna invent a summary for you 🫶

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🌸 SYNOPSIS 🌸

bool _dma_no_cache_snooping (struct ishtp_device *dev );

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🎀 ARGUMENTS 🎀

• dev — the ishtp device pointer, periodt.

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🦋 DESCRIPTION 🦋

So the vibe check here is: this function checks, on the current platform, whether DMA supports cache snooping or not. That’s the whole assignment, no cap.

This callback is used to notify the uplayer driver whether a manual cache flush is needed when doing DMA operation. Like, “hey bestie, do you need to flush this yourself or not?” energy 🔥

pay attention to this callback implementation, fr fr — if you declare that cache snooping is available on a platform that does not support cache snooping, the uplayer driver will receive mismatched data 😭. And if you declare no cache snooping on a platform that does support cache snooping, the cache gets flushed twice and you take a performance hit 💀.

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⭐ RETURN ⭐

• false — has cache snooping capability ✨
• true — no cache snooping, need manually cache flush 🧚

yes bestie, the booleans are built like that 🙈 — keep the meanings exactly as written.

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🌈 SEE ALSO 🌈

Kernel file ./drivers/hid/intel-ish-hid/ipc/ipc.c:

• ish_reg_read(9)
• ish_reg_write(9)
• _ish_read_fw_sts_reg(9)
• check_generated_interrupt(9)
• ish_is_input_ready(9)
• set_host_ready(9)
• ishtp_fw_is_ready(9)
• ish_set_host_rdy(9)
• ish_clr_host_rdy(9)
• ish_set_host_ready(9)
• _ishtp_read_hdr(9)
• _ishtp_read(9)
• write_ipc_from_queue(9)
• write_ipc_to_queue(9)
• ipc_send_mng_msg(9)
• timed_wait_for_timeout(9)
• ish_fw_reset_handler(9)
• fw_reset_work_fn(9)
• _ish_sync_fw_clock(9)
• recv_ipc(9)
• ish_irq_handler(9)
• ish_disable_dma(9)
• ish_wakeup(9)
• _ish_hw_reset(9)
• _ish_ipc_reset(9)
• ish_hw_start(9)
• ish_ipc_get_header(9)
• ish_dev_init(9)
• ish_device_disable(9)

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made with 💖 from the kernel API manual corner — source/version vibes: ./drivers/hid/intel-ish-hid/ipc, dated October 2026. stay snoopy, bestie 💅👑