Linux/WL1837MOD: dont have udev in the kernel for CRDA to work

Hi,

I am not familiar with mdev.
But have yo seen this e2e?:
e2e.ti.com/.../556517

Seems like CONFIG_CFG80211_INTERNAL_REGDB in the kernel .config helped.

You can also try setting the region using wpa_supplicant.conf

# Country code
# The ISO/IEC alpha2 country code for the country in which this device is
# currently operating.
country=US

Best Regards,
Eyal

Thank you for your reply. I figured out how to enable the udev in the rootfs and now I can get the 5g working.
I have a few more queries:
1. Everytime I try to connect to the AP using hostapd I get Authentication error two times and then I am able to connect. I did a bit of research and it seems like it is related to the entropy(randomness) which is used by hostapd for WPA. So i enabled haveged service which solves my problem Is that the correct approach? have to seen this scenario ? How does the CONFIG_NO_RANDOM_POOL option while building hostapd help ?

2. Now that I have both the 2.4g anf 5g working, I dont see a huge difference in the speeds when my tablet which is connected to the AP (when it is close by). But when I go far like 10 meters then the performance of 5G is better.. does that make sense? How can I measure the difference in the performance of the two bands.

3. I am also playing with the tx power of the device. I used the iwconfig command to set and get the tx power. when I dont change anything I get 23db. but when I lower the txpower I dont see the signal strength going down, Is that normal ? Is this the correct way of changing the tx ppower ? How are the tx power and signal strength related to each other ?

4. We will go for FCC testing at some point in time. Is there any Documentation for thresholds which my device should be operating at ? this will be for operation in US.

Thanks,
Surabhi.

Hi Surabhi,

Glad you got it working!

Are you connecting to the AP using hostapd or wpa_supplicant? Your product is a station, right?
Are you starting wpa_supplicant with "-e/data/misc/wifi/entropy.bin" or similar?

In terms of range actually 5GHz could be a little worse even with respect to range, as the wave length is shorter, but the air is usually less congested compared to the 2.4Ghz spectrum so it makes sense that it generally behaves better.

The Tx Power is controlled internally by the firmware and is dynamic based on the changing conditions in the air (retries, collisons etc.)
iwconfig is actually deprecated but in any case it can't be used for that.

You can control output power etc. using wl18xx-conf.bin but i don't recommand doing that as it effects certification:
www.ti.com/.../swru422a.pdf

As I believe that you are using our "WL1837MOD: module you should be able to resuse our certification documents.
All the info regarding certification is available in the following page:
processors.wiki.ti.com/.../WL18xx

under the "Certification Information" section.

Best Regards,
Eyal

Hi Eyal,
am using our device as AP. I am using hostapd for configuring it as AP. Once the hostapd is running, I connect a tablet or any smartphone to my device. am not using this -e/data/misc/wifi/entropy.bin" or similar for hostapd. My hostapd.conf looks like below :

interface=wlan0 # the interface used by the AP
hw_mode=a # a simply means 5GHz
channel=0 # the channel to use, 0 means the AP will search for the channel with the least interferences
ieee80211d=1 # limit the frequencies used to those allowed in the country
country_code=FR # the country code
ieee80211n=1 # 802.11n support
ieee80211ac=1 # 802.11ac support
wmm_enabled=1 # QoS support
ssid=somename # the name of the AP
auth_algs=1 # 1=wpa, 2=wep, 3=both
wpa=2 # WPA2 only
wpa_key_mgmt=WPA-PSK
rsn_pairwise=CCMP
wpa_passphrase=somepassword

The Tx Power is controlled internally by the firmware and is dynamic based on the changing conditions in the air (retries, collisons etc.)
iwconfig is actually deprecated but in any case it can't be used for that.--- did you mean that it "can" be used to change the tx power if needed ? Should the signal strength go down if the tx power is reduced ?

Thanks for the documentation link, will take some time to go over them.
This chip has bluetooth, BLE also, is there any link on how to enable that bluetooth functionality ? I have not enabled it yet.

Thanks and Regards,
Surabhi

Hi Eyal,
I wanted to check if I can set a fixed transmit power for the chip. I wanted to compare the performance of the wifi in same environment on two devices which have different enclosures. I wanted to have the same transmit power they are transmitting at ?

Also I wanted to understand if I set the below to same value for example 0xA will I fix the transmit power to 10db and the chip will always transmit at 10 db ?
TxPower_level_MaxPower wl18xx.phy.high_power_val
TxPower_level_MedPower wl18xx.phy.med_power_val
TxPower_level_LowPower wl18xx.phy.low_power_val

TxPower_level_MaxPower_2nd wl18xx.phy.high_power_val_2nd
TxPower_level_MedPower_2nd wl18xx.phy.med_power_val_2nd
TxPower_level_LowPower_2nd wl18xx.phy.low_power_val_2nd

Thanks,
Surabhi