NAME

     rtwn — Realtek IEEE 802.11 wireless network driver

SYNOPSIS

     options RTWN_DEBUG
     options RTWN_WITHOUT_UCODE

     To compile this driver into the kernel, place the following lines in your kernel
     configuration file:

           device rtwn
           device rtwnfw
           device rtwn_usb
           device rtwn_pci
           device wlan
           device firmware

     Alternatively, to load the driver as a module at boot time, place following lines in
     loader.conf(5):

           if_rtwn_pci_load="YES"
           if_rtwn_usb_load="YES"

DESCRIPTION

     The rtwn driver provides support for wireless network devices based on the Realtek RTL8192C,
     RTL8188E, RTL8192E, RTL8812A and RTL8821A programming APIs.  These APIs are used by a wide
     variety of chips; most chips with USB and some with PCI interface are supported.

     To enable use for PCI/PCIe systems, see the rtwn_pci(4) driver; for USB devices, use the
     rtwn_usb(4) driver.

     The driver supports station, adhoc, hostap and monitor mode operation.  There are no
     limitations for number of monitor mode virtual interfaces; in addition to any other virtual
     interface one station interface can be added (Note: RTL8821AU supports two non-monitor mode
     interfaces at the same time).

     All chips have hardware support for WEP, AES-CCM and TKIP encryption.

     The rtwn driver can be configured at runtime with ifconfig(8).

FILES

     /usr/share/doc/legal/realtek.LICENSE  rtwn firmware license

     The driver (if not compiled with options RTWN_WITHOUT_UCODE ) may use following firmware
     files, which are loaded when an interface is brought up:
           /boot/kernel/rtwn-rtl8188eefw.ko
           /boot/kernel/rtwn-rtl8188eufw.ko
           /boot/kernel/rtwn-rtl8192cfwE_B.ko
           /boot/kernel/rtwn-rtl8192cfwE.ko
           /boot/kernel/rtwn-rtl8192cfwT.ko
           /boot/kernel/rtwn-rtl8192cfwU.ko
           /boot/kernel/rtwn-rtl8192eufw.ko
           /boot/kernel/rtwn-rtl8812aufw.ko
           /boot/kernel/rtwn-rtl8821aufw.ko

EXAMPLES

     Join an existing BSS network (i.e., connect to an access point):

           ifconfig wlan create wlandev rtwn0 inet 192.168.0.20 \
               netmask 0xffffff00

     Join a specific BSS network with network name “my_net”:

           ifconfig wlan create wlandev rtwn0 ssid my_net up

     Join a specific BSS network with 64-bit WEP encryption:

           ifconfig wlan create wlandev rtwn0 ssid my_net \
                   wepmode on wepkey 0x1234567890 weptxkey 1 up

     Create an IBSS network with 128-bit WEP encryption on the channel 4:

           ifconfig wlan create wlandev rtwn0 wlanmode adhoc ssid my_net \
                   wepmode on wepkey 0x01020304050607080910111213 weptxkey 1 \
                   channel 4

     Join/create an 802.11b IBSS network with network name “my_net”:

           ifconfig wlan0 create wlandev rtwn0 wlanmode adhoc
           ifconfig wlan0 inet 192.168.0.22 netmask 0xffffff00 ssid my_net \
                   mode 11b

     Create a host-based access point:

           ifconfig wlan0 create wlandev rtwn0 wlanmode hostap
           ifconfig wlan0 inet 192.168.0.10 netmask 0xffffff00 ssid my_ap

LOADER TUNABLES

     Tunables can be set at the loader(8) prompt before booting the kernel or stored in
     loader.conf(5).

     dev.rtwn.%d.hwcrypto
             This tunable controls how key slots are assigned:
             0 - disable h/w crypto support. Features that require access to frame contents
             (e.g., TCP/UDP/IP Rx checksum validation) will not work;
             1 - use h/w crypto support for pairwise keys only;
             2 - use h/w crypto support for all keys; may not work for multi-vap configurations.
             By default it is set to 1.

     dev.rtwn.%d.ratectl
             This tunable switches between rate control implementations:
             0 - no rate control;
             1 - driver sends 'tx complete' reports to net80211; algorithm is controlled via
             net80211;
             2 - firmware-based rate control.
             By default it is set to 1; however driver may choose another algorithm in case if it
             is not implemented
             Currently selected algorithm is reported via dev.rtwn.%d.ratectl_selected read-only
             OID.

     dev.rtwn.%d.rx_buf_size
             (USB only) Controls size of temporary Rx buffer; smaller buffer size may increase
             number of interrupts.

DIAGNOSTICS

     rtwn%d: could not read efuse byte at address 0x%x
     rtwn%d: %s: cannot read rom, error %d  There was an error while reading ROM; device attach
     will be aborted.  This should not happen.

     rtwn%d: failed loadfirmware of file %s  For some reason, the driver was unable to read the
     microcode file from the filesystem.  The file might be missing or corrupted.  The driver
     will disable firmware-dependent features.

     rtwn%d: wrong firmware size (%zu)
     rtwn%d: %s: failed to upload firmware %s (error %d)
     rtwn%d: timeout waiting for firmware readiness  Firmware upload failed; the file might be
     corrupted.  The driver will disable firmware-dependent features.  This should not happen.

     rtwn%d: device timeout  A frame dispatched to the hardware for transmission did not complete
     in time.  The driver will reset the hardware.  This should not happen.

SEE ALSO

     intro(4), netintro(4), rtwn_pci(4), rtwn_usb(4), rtwnfw(4), wlan(4), wlan_amrr(4),
     wlan_ccmp(4), wlan_tkip(4), wlan_wep(4), wlan_xauth(4), hostapd(8), ifconfig(8),
     wpa_supplicant(8)

HISTORY

     The urtwn driver first appeared in OpenBSD 4.9 and FreeBSD 10.0; the rtwn driver first
     appeared in OpenBSD 5.8.

AUTHORS

     The rtwn driver was initially written by Stefan Sperling <stsp@openbsd.org> and ported by
     Kevin Lo <kevlo@freebsd.org>.  It was based on the urtwn driver written by Damien Bergamini
     <damien.bergamini@free.fr>.

BUGS

     The rtwn driver currently does not implement firmware-based rate control.