lan78xx_configure_usb(9)

🌸 NAME 🌸

hey bestie, welcome to lan78xx_configure_usb(9) from the Kernel API Manual 💅 — this one is all about Configure USB link power settings. slay.

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✨ SYNOPSIS ✨

int lan78xx_configure_usb (struct lan78xx_net *dev , int speed );

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🎀 ARGUMENTS 🎀

• dev — pointer to the LAN78xx device structure 🫶
• speed — negotiated Ethernet link speed (in Mbps) ⚡

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🦋 DESCRIPTION 🦋

okay so here’s the tea: this function configures U1/U2 link power management for SuperSpeed USB devices based on the current Ethernet link speed. it’s giving very “know your speed, manage your power” energy ✨

it uses the USB_CFG1 register to enable or disable U1 and U2 low-power states. literally the USB_CFG1 register is the main character here 👑

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💀 NOTE 💀

only LAN7800 and LAN7801 support SuperSpeed (USB 3.x). LAN7850 is a High-Speed-only (USB 2.0) device and is skipped 🙈

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🌈 RETURN 🌈

0 on success or a negative error code on failure. periodt 💅

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🔥 SEE ALSO 🔥

• Kernel file: ./drivers/net/usb/lan78xx.c
• lan78xx_phy_int_ack(9)
• lan78xx_configure_flowcontrol(9)
• lan78xx_mac_eee_enable(9)
• lan78xx_set_fixed_link(9)
• lan78xx_get_phy(9)
• lan78xx_mac_prepare_for_phy(9)
• lan78xx_configure_leds_from_dt(9)

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okay that’s the whole page, bestie 🫶 the footer’s source/version bit is ./drivers/net/usb, the date is October 2026, and the page itself is obviously lan78xx_configure_usb(9) 💖✨