Re: [rt2x00-users] [PATCH 3.11] rt2800: fix wrong TX power compensation

[Stanislaw Gruszka <sgruszka@redhat.com>]

On Tue, Aug 27, 2013 at 10:22:45AM +0200, Paul Menzel wrote:
> > I checked 2 devices (3071 & 3070) but they have EXTERNAL_TX_ALC bit set.
> > I assume the fix is correct based on vendor driver and it fixes devices
> > which have no EXTERNAL_TX_ACL, but I can not tell what chipset that are.
> > Is possible that the same chipset can be configured with and without
> > EXTERNAL_TX_ALC.
> 
> I have the following device.
> 
>         $ lsusb -s 004
>         Bus 002 Device 004: ID 148f:2870 Ralink Technology, Corp. RT2870 Wireless Adapter
> 
> How do I check if the bit is set? Sometimes the device disconnects when
> being 10 meters away from the access point. The connection is also
> slower than with an ath5k device right next to it.

If you compiled kernel with DEBUGFS support, you can check that by:

mount -t debugfs debugfs /sys/kernel/debug/
cd /sys/kernel/debug/ieee80211/phy0/rt2800usb/register/
echo "0x001b" > eeprom_offset
cat eeprom_value

Second less significant bit is EXTERNAL_TX_ALC .

I think your device has EXTERNAL_TX_ACL since it's older chip, but who
knows ...

Stanislaw