rio_request_outb_mbox(9)

💌 rio_request_outb_mbox(9) — from the Kernel API Manual, bestie 💌

okay so picture this: you're deep in RapidIO land and you need to send a message out. that's literally this function. it claims an outbound mailbox for you and hooks up your callback. let's go ✨

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✨ SYNOPSIS ✨

int rio_request_outb_mbox (struct rio_mport *mport , void *dev_id , int
mbox , int entries , void (*moutb) (struct rio_mport * mport, void
*dev_id, int mbox, int slot) );

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🎀 ARGUMENTS 🎀

• mport — the RIO master port you're pulling the mailbox resource out of. your source of truth, your main character port 👑
• dev_id — a device-specific pointer that gets handed back to you on the event. like your little name tag 🏷️
• mbox — the mailbox number you're claiming. pick your locker, bestie 🔐
• entries — how many entries the outbound mailbox queue holds. size it right fr fr 📏
• moutb — the callback that fires when the outbound message is actually sent. it gets (struct rio_mport * mport, void *dev_id, int mbox, int slot). this is the moment she shines 💅

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🌸 DESCRIPTION 🌸

so what this does: it requests ownership of an outbound mailbox resource, and it binds a callback function to that resource. the way it just… does both in one call? iconic.

returns 0 on success. that's it, that's the whole vibe ✅

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🦋 SEE ALSO 🦋

kernel file ./drivers/rapidio/rio.c — and honestly the whole friend group showed up, so let's list them all:

• rio_local_get_device_id(9)
• rio_query_mport(9)
• rio_alloc_net(9)
• rio_local_set_device_id(9)
• rio_add_device(9)
• rio_request_inb_mbox(9)
• rio_release_inb_mbox(9)
• rio_release_outb_mbox(9)
• rio_setup_inb_dbell(9)
• rio_request_inb_dbell(9)
• rio_release_inb_dbell(9)
• rio_request_outb_dbell(9)
• rio_release_outb_dbell(9)
• rio_add_mport_pw_handler(9)
• rio_del_mport_pw_handler(9)
• rio_request_inb_pwrite(9)
• rio_release_inb_pwrite(9)
• rio_pw_enable(9)
• rio_map_inb_region(9)
• rio_unmap_inb_region(9)
• rio_map_outb_region(9)
• rio_unmap_outb_region(9)
• rio_mport_get_physefb(9)
• rio_get_comptag(9)
• rio_set_port_lockout(9)
• rio_enable_rx_tx_port(9)
• rio_chk_dev_route(9)
• rio_mport_chk_dev_access(9)
• rio_chk_dev_access(9)
• rio_get_input_status(9)
• rio_clr_err_stopped(9)
• rio_inb_pwrite_handler(9)
• rio_mport_get_efb(9)
• rio_mport_get_feature(9)
• rio_std_route_add_entry(9)
• rio_std_route_get_entry(9)
• rio_std_route_clr_table(9)
• rio_lock_device(9)
• rio_unlock_device(9)
• rio_route_add_entry(9)
• rio_route_get_entry(9)
• rio_route_clr_table(9)
• rio_request_mport_dma(9)
• rio_release_dma(9)
• rio_dma_prep_xfer(9)
• rio_register_scan(9)
• rio_mport_scan(9)

like, the entire lineup. no cap 🫶

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ngl if you're claiming an outbound mailbox, go read rio_release_outb_mbox(9) too — you don't want to be the girl who never gives the resource back 🙈

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okay that's the page!! this one's from the Kernel API Manual, lives under ./drivers/rapidio in the source, and it's dated October 2026. mwah, go slay your RapidIO messages bestie 💖🎀🦋