STRUCT CHANNEL(9)

💅 struct channel(9) 💅

okay so bestie, welcome to the struct channel(9) page from the Kernel API Manual — yes we're reading kernel API docs together, this is our bonding era 🫶

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✨ NAME ✨

struct channel — it's a private structure, like a little diary 📓 that keeps channel-specific data. not for everyone's eyes, just the channel's, iykyk 💅

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🦋 SYNOPSIS 🦋

struct channel {
    struct snd_pcm_substream *substream;
    struct snd_pcm_hardware pcm_hardware;
    struct most_interface *iface;
    struct most_channel_config *cfg;
    struct snd_card *card;
    struct list_head list;
    int id;
    unsigned int period_pos;
    unsigned int buffer_pos;
    bool is_stream_running;
    struct task_struct *playback_task;
    wait_queue_head_t playback_waitq;
    void (*copy_fn)(void *alsa, void *most, unsigned int bytes);
};

look at her. the whole squad is in there 💖

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🎀 Members 🎀

so literally every field gets its moment, no skips, no cap:

• substream — stores the substream structure. she holds the substream, that's her job, periodt ✨
• pcm_hardware — the low-level hardware description. the down-and-dirty hardware lore 🔥
• iface — the interface that this channel belongs to. whose channel is it anyway 💁‍♀️
• cfg — channel configuration. the settings, the vibes, the whole setup 🌸
• card — the registered sound card. she's registered, she's official 👑
• list — a list for private use. do not perceive it, it's private 🙈
• id — the channel index. her number, her identity ⭐
• period_pos — current period position (ring buffer). very ring buffer of her 🎀
• buffer_pos — current buffer position (ring buffer). yes, also ring buffer 💀
• is_stream_running — identifies whether a stream is running or not. the vibe check: running or not running 🌈
• playback_task — the playback thread. the main character doing the playback work 💅
• playback_waitq — the waitq used by the playback thread. it's a wait queue, lowercase waitq, we respect the abbreviation 🫶
• copy_fn — copy function for PCM-specific format and width. a function pointer doing the copying for the PCM-specific format and width, iconic behavior honestly ⭐

fr fr every single one of those fields is real and load-bearing, don't go deleting anything just because it looks quiet 😭

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🌟 SEE ALSO 🌟

• Kernel file ./drivers/most/most_snd.c and her little friends: get_channel(9), copy_data(9), playback_thread(9), pcm_open(9), pcm_close(9), pcm_prepare(9), pcm_trigger(9), pcm_pointer(9), audio_probe_channel(9), audio_disconnect_channel(9), audio_rx_completion(9), audio_tx_completion(9)

that's the whole group chat, go read them next 🦋

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and that's the page bestie!! sourced from ./drivers/most, dated October 2026, and filed under struct channel(9) — slay, you now know more about kernel channel structs than 99% of people at this party 💜✨🎀