Enabling WiFi after firmware installation

I have a computer running Debian 12 (stable) that I want to connect wirelessly to the internet. The computer has a builtin WiFi adapter which uses the firmware brcmfmac4330 and is available in the package firmware-brcm80211. After having installed the firmware the interface wlan0 shows up but its state is DOWN. However, even after trying to bring it up it's still down. Also, the interface is not blocked. How can I troubleshoot this problem? $ sudo ip link set wlan0 up $ ip link 1: lo: mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: end0: mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000 link/ether d0:63:b4:00:97:0e brd ff:ff:ff:ff:ff:ff 3: wlan0: mtu 1500 qdisc fq_codel state DOWN mode DORMANT group default qlen 1000 link/ether 4c:aa:16:fe:ca:f7 brd ff:ff:ff:ff:ff:ff $ sudo rfkill ID TYPE DEVICE SOFT HARD 0 wlan phy0 unblocked unblocked $ uname -a Linux server 6.1.0-37-armmp #1 SMP Debian 6.1.140-1 (2025-05-22) armv7l GNU/Linux