zynqmp_dp_aux_cmd_submit(9)

okay bestie, you’re on the zynqmp_dp_aux_cmd_submit(9) page of the Kernel API Manual ✨ and it’s literally all about submitting an aux command. Let’s get into it 💅

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💖 NAME 💖

zynqmp_dp_aux_cmd_submit — Submit aux command 🎀

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✨ SYNOPSIS ✨

Here’s the signature, no cap:

int zynqmp_dp_aux_cmd_submit (struct zynqmp_dp *dp , u32 cmd , u16 addr
       , u8 *buf , u8 bytes , u8 *reply );

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🫶 ARGUMENTS 🫶

• dp — the DisplayPort IP core structure 💖
• cmd — the aux command
• addr — the aux address
• buf — buffer for command data
• bytes — number of bytes for buf
• reply — reply code to be returned 👑

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🌈 DESCRIPTION 🌈

Okay so this function submits an aux command. Literally all aux related commands — native or i2c aux read/write — are submitted through this function. The function is mapped to the transfer function of struct drm_dp_aux. It involves multiple register reads/writes, so synchronization is needed, and that’s done by drm_dp_helper using hw_mutex.

If there’s no immediate reply to the command submission, the calling thread goes into sleep 😴. The reply code is returned at reply if reply != NULL — periodt.

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💅 RETURN 💅

It gives you 0 if the command is submitted properly, or the corresponding error code:

• -EBUSY — when there is any request already being processed 😭
• -ETIMEDOUT — when receiving reply is timed out 💀
• -EIO — when received bytes are less than requested 🙈

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🦋 SEE ALSO 🦋

Kernel file: ./drivers/gpu/drm/xlnx/zynqmp_dp.c

The whole bestie reference list:

• struct zynqmp_dp_link_config(9)
• struct zynqmp_dp_mode(9)
• struct zynqmp_dp_config(9)
• enum test_pattern(9)
• struct zynqmp_dp_test(9)
• struct zynqmp_dp_train_set_priv(9)
• struct zynqmp_dp(9)
• zynqmp_dp_phy_init(9)
• zynqmp_dp_phy_exit(9)
• zynqmp_dp_phy_probe(9)
• zynqmp_dp_phy_ready(9)
• zynqmp_dp_max_rate(9)
• zynqmp_dp_mode_configure(9)
• zynqmp_dp_adjust_train(9)
• zynqmp_dp_update_vs_emph(9)
• zynqmp_dp_link_train_cr(9)
• zynqmp_dp_link_train_ce(9)
• zynqmp_dp_setup(9)
• zynqmp_dp_train(9)
• zynqmp_dp_train_loop(9)
• zynqmp_dp_aux_init(9)
• zynqmp_dp_aux_cleanup(9)
• zynqmp_dp_update_misc(9)
• zynqmp_dp_set_format(9)
• zynqmp_dp_encoder_mode_set_transfer_unit(9)
• zynqmp_dp_encoder_mode_set_stream(9)
• zynqmp_dp_disp_connected_live_layer(9)
• zynqmp_dp_set_test_pattern(9)
• zynqmp_dp_enable_vblank(9)
• zynqmp_dp_disable_vblank(9)

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Cute little sign-off: source/version ./drivers/gpu/drm/xlnx, dated October 2026, for zynqmp_dp_aux_cmd_submit(9) 💖🧚‍♀️✨