v4l2_get_active_data_lanes(9)

💖 NAME 💖

okay so bestie, welcome to the Kernel API Manual — this page is serving v4l2_get_active_data_lanes, aka the function that gets the number of active data lanes from the driver. no cap, that's literally the whole name vibe. 💅✨

---

🎀 SYNOPSIS 🎀

here's the signature, character for character, bestie:

int v4l2_get_active_data_lanes (const struct media_pad *pad , unsigned
int max_data_lanes );

---

🌸 ARGUMENTS 🌸

• pad — the transmitter's media pad. 📡
• max_data_lanes — the maximum number of active data lanes supported by the MIPI CSI link in hardware. 🔥

---

🦋 DESCRIPTION 🦋

okay so the whole point of this function is obtaining the number of data lanes that are actively being used by the driver for a MIPI CSI-2 device on a given media pad. that's the main character energy of it. 🌈

and where does that info come from? it's derived from a mbus_config fetched from a device driver using the get_mbus_config v4l2_subdev pad op. periodt. it's giving “ask the driver nicely and read the mbus config” 💖

---

⭐ RETURN ⭐

here's the vibe check on what comes back:

• >0 — Number of active data lanes. 👑
• -EINVAL — Number of active data lanes is invalid, as it exceeds the maximum supported data lanes. 🚨 not the slay result, bestie 🚨

---

💜 SEE ALSO 💜

okay the Kernel file is ./include/media/v4l2-common.h, and the whole reference squad is:

• v4l2_ctrl_query_fill(9)
• enum v4l2_i2c_tuner_type(9)
• v4l2_i2c_new_subdev(9)
• v4l2_i2c_new_subdev_board(9)
• v4l2_i2c_subdev_set_name(9)
• v4l2_i2c_subdev_init(9)
• v4l2_i2c_subdev_addr(9)
• v4l2_i2c_tuner_addrs(9)
• v4l2_i2c_subdev_unregister(9)
• v4l2_spi_new_subdev(9)
• v4l2_spi_subdev_init(9)
• v4l2_spi_subdev_unregister(9)
• v4l_bound_align_image(9)
• v4l2_find_nearest_size_conditional(9)
• v4l2_find_nearest_size(9)
• v4l2_g_parm_cap(9)
• v4l2_s_parm_cap(9)
• enum v4l2_pixel_encoding(9)
• struct v4l2_format_info(9)
• v4l2_get_link_freq(9)
• v4l2_link_freq_to_bitmap(9)
• devm_v4l2_sensor_clk_get(9)
• devm_v4l2_sensor_clk_get_legacy(9)

---

mwah 💋 this page's source is ./include/media, it's dated October 2026, and the page version is v4l2_get_active_data_lanes(9) — bye bestie! 🎀🫶