802.11ax ER-SU (Extended Rates SU) Support#
To enable ER-SU (Extended Rates SU) support, use module parameters and debugfs. Accordingly, auto-rate table will be changed, as shown below.
| config_er_su Value | Description | Auto Rate Table Change | 
|---|---|---|
| 0 | Don't use ER-SU rates even though AP supports ER-SU transmissions | No change | 
| 1 | Use ER-SU rates along with other non-ER SU rates if AP supports | Add ER-SU rate along with non ER-SU rates | 
| 2 | Use only ER-SU rates in auto rate if AP supports | Add only ER-SU rate | 
Note:
Auto rate table should be updated to firmware on dynamic change from the user or from AP.
Fixed rate should also be configured based on config_er_su.
config_er_su=2 uses ER-SU rate and limits ER-SU rate to mcs2.
config_er_su=1 still uses non ER-SU rates.
Enabling ER-SU PPDU Transmission Support#
The driver can enable ER-SU PPDU transmission support through module param and update it dynamically through debugfs. Follow the steps below to enable ER-SU.
- Compile the driver as described in the Compilation Steps section. - #make clean;make
- Navigate to the release folder and run the following commands to insert the driver. - # cd release # insmod rsi_91x.ko driver_mode_value=1 rsi_zone_enabled=0x601 config_er_su=1/2 # insmod rsi_sdio.ko
- To connect to the third access point (AP), run the following command: - # wpa_supplicant -i <interface_name> -D nl80211 -c <sta_settings.conf > -ddddt > log1 &- See the Configure Station using WPA Supplicant section for different options in wpa_supplicant. 
- To dynamically change the config_er_su value, use the command below after connection. - # echo 2 >/sys/kernel/debug/phyX/config_er_su
- To check the config_er_su value, use the command below. - # cat /sys/kernel/debug/phyX/config_er_su
- To use the fixed rate in ER-SU, follow the steps described in the Configuring the 802.11ax Wi-Fi Data Rate section.