ksz879x_set_loopback(9)

💅 ksz879x_set_loopback(9) 💅

okay so bestie, welcome to the Kernel API Manual ✨ this one's from the kernel API manual, and it's literally all about ksz879x_set_loopback — a KSZ879x specific function to set loopback mode for a specific port 🎀

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🌸 NAME 🌸

ksz879x_set_loopback — a KSZ879x specific function to set loopback mode for a specific port 🦋

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✨ SYNOPSIS ✨

int ksz879x_set_loopback (struct ksz_device *dev , u16 port , u16 val );

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🎀 ARGUMENTS 🎀

• dev — Pointer to the device structure. yes queen, hand over the whole device 💖
• port — Port number to modify. like, which port are we doing a lil makeover on 💅
• val — Value indicating whether to enable or disable loopback mode. it's giving on/off energy 🔥

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🦋 DESCRIPTION 🦋

okay so here's the vibe: this function translates loopback bit of the BMCR register into the corresponding hardware register bit value and writes it to the SMI interface ✨ no cap, that's literally the whole job. it's a translator. a little bilingual icon between register worlds 🌈

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⭐ RETURN ⭐

• 0 on success 💖
• error code on failure 😭

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👑 SEE ALSO 👑

• Kernel file ./drivers/net/dsa/microchip/ksz8.c
• ksz8_ind_write8(9)
• ksz8_ind_read8(9)
• ksz879x_get_loopback(9)
• ksz8_r_phy_ctrl(9)
• ksz8_r_phy_bmcr(9)
• ksz8_w_phy_ctrl(9)
• ksz8_w_phy_bmcr(9)
• ksz88x3_tc_ets_add(9)
• ksz88x3_tc_ets_del(9)
• ksz8_phy_port_link_up(9)
• ksz8_cpu_port_link_up(9)
• ksz88x3_drive_strength_write(9)
• ksz8_parse_drive_strength(9)

like, go read all of those too, bestie, they're all in ./drivers/net/dsa/microchip 🫶

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real talk: this page lives in ./drivers/net/dsa/microchip, dated October 2026, and it's part of the same ksz879x_set_loopback(9) situation you just read about 💜

anyway that's the whole page, mwah 💋 periodt 🧚