ep93xx_spi_read_write(9)

💅 ep93xx_spi_read_write(9) — the Kernel API Manual glow-up ✨

okay so bestie, this is a page from the Kernel API Manual and it's about ep93xx_spi_read_write, which is genuinely one of those little functions that keeps the whole SPI vibe going. no cap. let's get into it 🎀

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🌸 NAME 🌸

ep93xx_spi_read_write — literally just perform next RX/TX transfer. that's the whole job. iconic behaviour, honestly 🦋

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✨ SYNOPSIS ✨

int ep93xx_spi_read_write(struct spi_controller *host);

she takes one arg and hands you back an int. simple. clean. main character energy 💅

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🫶 ARGUMENTS 🫶

• host — the SPI host. yes, that's it. that's the argument. your SPI host, your bestie, the one carrying the whole controller situation 🙈

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👑 DESCRIPTION 👑

okay so here's what she does: this function transfers the next bytes (or half-words) to/from the RX/TX FIFOs. the way that it just moves data like it's nothing 😭

and listen — if you call it several times, the whole transfer will be completed. she's not a one-and-done girlie, she's a keep going until it's done girlie.

returns:

• -EINPROGRESS when the current transfer was not yet completed — she's still cooking, give her a sec 🔥
• 0 otherwise — we're done here, slay ✅

heads up, when this function is finished, the RX FIFO should be empty and the TX FIFO should be full. like, that's the vibe check. if that's not the state of things, something's off fr fr 👀

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🌈 SEE ALSO 🌈

go read these too, bestie, they're all in the same friend group:

• Kernel file ./drivers/spi/spi-ep93xx.c
• struct ep93xx_spi(9)
• ep93xx_spi_calc_divisors(9)
• ep93xx_spi_dma_prepare(9)
• ep93xx_spi_dma_finish(9)

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and that's the whole page, periodt 💖

this little section lives in ./drivers/spi, it's dated October 2026, and it comes to you straight from the Kernel API Manual — go forth and transfer those bytes, queen 👑🎀