snd_pcm_set_...d_buffer_all(9)

✨ snd_pcm_set_...d_buffer_all(9) ✨

okay bestie, so this page lives in the Kernel API Manual and it's all about snd_pcm_set_fixed_buffer_all — the function that preallocates AND sets up the fixed size PCM buffer for you. like, the whole entire thing. no cap 💖

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🌸 NAME 🌸

snd_pcm_set_fixed_buffer_all — preallocate and set up the fixed size PCM buffer, bestie. that's the whole vibe. 🎀

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🦋 SYNOPSIS 🦋

int snd_pcm_set_fixed_buffer_all (struct snd_pcm *pcm , int type ,
       struct device *data , size_t size );

literally copy that signature exactly, ok? it's giving "type it carefully" energy 😭

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💅 ARGUMENTS 💅

• pcm — the pcm instance, the main character of this whole operation 👑
• type — the DMA type, and it's one of the SNDRV_DMA_TYPE_* family (* = whatever flavor you pick, iykyk)
• data — DMA type dependent data, so it's whatever the DMA type needs. matching vibes only 🫶
• size — the requested pre-allocation size, measured in bytes. bytes, not vibes. 🍓

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🔥 DESCRIPTION 🔥

so what it actually does: it applies the set up of the fixed buffer via snd_pcm_set_fixed_buffer for all substream. every single one. periodt. 💯

and real talk — if any of allocation fails, it returns -ENOMEM. so the caller must check the return value. do not skip the vibe check on that return value, bestie, that's how you get a sad kernel 😭✨

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⭐ RETURN ⭐

zero if successful, or a negative error code. that's it, that's the tea 💀

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🌈 SEE ALSO 🌈

okay this list is long but every single one of these is iconic and you're gonna read all of them, no skipping 👑💅

• Kernel file ./include/sound/pcm.h
• snd_pcm_stream_linked(9)
• snd_pcm_stream_lock_irqsave(9)
• snd_pcm_stream_lock_irqsave_nested(9)
• snd_pcm_group_for_each_entry(9)
• snd_pcm_running(9)
• __snd_pcm_set_state(9)
• bytes_to_samples(9)
• bytes_to_frames(9)
• samples_to_bytes(9)
• frames_to_bytes(9)
• frame_aligned(9)
• snd_pcm_lib_buffer_bytes(9)
• snd_pcm_lib_period_bytes(9)
• snd_pcm_playback_avail(9)
• snd_pcm_capture_avail(9)
• snd_pcm_playback_hw_avail(9)
• snd_pcm_capture_hw_avail(9)
• snd_pcm_playback_ready(9)
• snd_pcm_capture_ready(9)
• snd_pcm_playback_data(9)
• snd_pcm_playback_empty(9)
• snd_pcm_capture_empty(9)
• snd_pcm_trigger_done(9)
• params_channels(9)
• params_rate(9)
• params_period_size(9)
• params_periods(9)
• params_buffer_size(9)
• params_buffer_bytes(9)
• snd_pcm_hw_constraint_single(9)
• snd_pcm_format_cpu_endian(9)
• snd_pcm_set_sync(9)
• snd_pcm_set_runtime_buffer(9)
• snd_pcm_gettime(9)
• snd_pcm_set_fixed_buffer(9)
• snd_pcm_sgbuf_get_addr(9)
• snd_pcm_sgbuf_get_chunk_size(9)
• snd_pcm_limit_isa_dma_size(9)
• snd_pcm_direction_name(9)
• snd_pcm_stream_str(9)
• snd_pcm_chmap_substream(9)
• pcm_format_to_bits(9)
• pcm_for_each_format(9)

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that's the whole page, bestie, you ate that 🫶💖

🎀 cute little sign-off: this one ships from ./include/sound and it's dated October 2026. iconic. mwah 💋✨