tsi721_cread_dma(9)

✨ tsi721_cread_dma(9) ✨

okay bestie, welcome to the kernel API manual for tsi721_cread_dma 💅 this little icon lives in section 9 of the Kernel API Manual, and honestly? she's serving "one job, does it well" energy. let's get into it 🎀

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🌸 NAME 🌸

tsi721_cread_dma — Generate a RapidIO maintenance read transaction using Tsi721 BDMA engine.

like, that's literally her whole personality. a maintenance read, but she's using the BDMA engine to do it. main character behavior fr 🔥

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🦋 SYNOPSIS 🦋

int tsi721_cread_dma (struct rio_mport *mport , int index , u16 destid ,
u8 hopcount , u32 offset , int len , u32 *data );

seven arguments, zero chill. she ate 💖

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💜 ARGUMENTS 💜

• mport — the RapidIO master port control structure. this is the boss of the operation, show some respect 👑
• index — ID of RapdiIO interface. yes. it says "RapdiIO". i don't make the rules, i just report them 😭 (it's the interface ID, that's the tea 🍓)
• destid — Destination ID of transaction. where we're going, bestie 🗺️
• hopcount — Number of hops to target device. count 'em. every single one 🐰
• offset — Offset into configuration space. where in the config space we're poking around 🔍
• len — Length (in bytes) of the maintenance transaction. she comes in bytes, no cap 📏
• data — Location to be read into. this is the bucket the read data lands in 🪣

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🌈 DESCRIPTION 🌈

Generates a RapidIO maintenance read transaction. that's it, that's the whole vibe. iconic, unbothered, moisturized ✨

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⭐ RETURN ⭐

0 on success and -EINVAL or -EFAULT on failure.

so like — zero, slay, we love to see it 🫶. anything else and you're getting -EINVAL or -EFAULT thrown back at you, and that's the vibe check failing 💀

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🎀 SEE ALSO 🎀

kernel file ./drivers/rapidio/devices/tsi721.c and the whole friend group:

• tsi721_lcread(9)
• tsi721_lcwrite(9)
• tsi721_maint_dma(9)
• tsi721_cwrite_dma(9)
• tsi721_pw_handler(9)
• tsi721_pw_enable(9)
• tsi721_dsend(9)
• tsi721_dbell_handler(9)
• tsi721_irqhandler(9)
• tsi721_omsg_msix(9)
• tsi721_imsg_msix(9)
• tsi721_srio_msix(9)
• tsi721_sr2pc_ch_msix(9)
• tsi721_request_msix(9)
• tsi721_enable_msix(9)
• tsi721_init_pc2sr_mapping(9)
• tsi721_rio_map_inb_mem(9)
• tsi721_rio_unmap_inb_mem(9)
• tsi721_init_sr2pc_mapping(9)
• tsi721_port_write_init(9)
• tsi721_bdma_maint_init(9)
• tsi721_add_outb_message(9)
• tsi721_omsg_handler(9)
• tsi721_open_outb_mbox(9)
• tsi721_close_outb_mbox(9)
• tsi721_imsg_handler(9)
• tsi721_open_inb_mbox(9)
• tsi721_close_inb_mbox(9)
• tsi721_add_inb_buffer(9)
• tsi721_get_inb_message(9)
• tsi721_messages_init(9)
• tsi721_query_mport(9)
• tsi721_disable_ints(9)
• tsi721_setup_mport(9)

thirty-four besties. a whole group chat. iykyk 💜

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ngl, if you're deep in the Tsi721 driver, this is your girl. go read the whole squad above if you want the full lore 🌸

okay that's the page!! who wrote it: source ./drivers/rapidio/devices, version date October 2026, and it's tsi721_cread_dma(9) forever and always 💅✨