v4l2_link_freq_to_bitmap(9)

💖 v4l2_link_freq_to_bitmap(9) — Kernel API Manual 💖

okay so bestie, welcome to the Kernel API Manual page for v4l2_link_freq_to_bitmap(9) — manual name folded in right up top, cute and accounted for. 🫶 This one is all about figuring out which link frequencies your platform actually supports. ✨

🌸 NAME 🌸

Figure out platform-supported link frequencies — literally the whole assignment. 💅

✨ SYNOPSIS ✨

int v4l2_link_freq_to_bitmap (struct device *dev , const u64
*fw_link_freqs , unsigned int num_of_fw_link_freqs , const s64
*driver_link_freqs , unsigned int num_of_driver_link_freqs , unsigned
long *bitmap );

🎀 ARGUMENTS 🎀

• dev — the struct device in question. 🫶
• fw_link_freqs — array of link frequencies from firmware. ✨
• num_of_fw_link_freqs — number of entries in fw_link_freqs. 🔢
• driver_link_freqs — array of link frequencies supported by the driver. 💅
• num_of_driver_link_freqs — number of entries in driver_link_freqs. 🧮
• bitmap — bitmap of driver-supported link frequencies found in fw_link_freqs. 🎀

🦋 DESCRIPTION 🦋

Okay so here’s the tea: this function checks which driver-supported link frequencies are enabled in system firmware, and then it sets the corresponding bits in bitmap — after first zeroing bitmap out. ✨ So yes, zero first, then set the matching bits. No cap. 💅

🌸 RETURN 🌸

• 0 — success, slay. ✅
• -ENOENT — no match found between driver-supported link frequencies and those available in firmware. 😭
• -ENODATA — no link frequencies were specified in firmware. 💀

🌈 SEE ALSO 🌈

Kernel file ./include/media/v4l2-common.h — and the rest of the friend group 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_get_active_data_lanes(9)
• devm_v4l2_sensor_clk_get(9)
• devm_v4l2_sensor_clk_get_legacy(9)

mwah 💋 — source ./include/media, date October 2026, page v4l2_link_freq_to_bitmap(9), in the Kernel API Manual. 🫶