spi_w8r8(9)

✨ spi_w8r8(9) — the Kernel API Manual page, bestie ✨

okay so this is spi_w8r8(9) from the Kernel API Manual, and it's giving “tiny SPI helper with main character energy” 💅

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🌸 NAME 🌸

spi_w8r8 — SPI synchronous 8 bit write followed by 8 bit read, no cap ✨

🎀 SYNOPSIS 🎀

ssize_t spi_w8r8 (struct spi_device *spi , u8 cmd );

💖 ARGUMENTS 💖

• spi — the device with which data will be exchanged 🫶
• cmd — the command to be written before data is read back 🎀

😴 CONTEXT 😴

can sleep — yes bestie, this one is allowed to snooze 😭💤

🦋 DESCRIPTION 🦋

Callable only from contexts that can sleep. That's the whole vibe check: if your context can't sleep, this is not the function for you, periodt 💀

🔥 RETURN 🔥

the (unsigned) eight bit number returned by the device, or else a negative error code 😭

🌈 SEE ALSO 🌈

Kernel file ./include/linux/spi — plus all these linked besties:

• struct spi_statistics(9)
• struct spi_delay(9)
• struct spi_device(9)
• struct spi_driver(9)
• spi_unregister_driver(9)
• module_spi_driver(9)
• struct spi_controller(9)
• struct spi_res(9)
• struct spi_transfer(9)
• struct spi_message(9)
• spi_message_init_with_transfers(9)
• spi_is_bpw_supported(9)
• spi_bpw_to_bytes(9)
• spi_controller_xfer_timeout(9)
• struct spi_replaced_transfers(9)
• spi_sync_transfer(9)
• spi_write(9)
• spi_read(9)
• spi_w8r16(9)
• spi_w8r16be(9)
• struct spi_board_info(9)

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mwah 💋 this page came from ./include/linux/spi and it's dated October 2026 — iconic, honestly 🫶✨