Re: [PATCH v2 1/2] cfg80211: last ack signal support in station dump

[Johannes Berg <johannes@sipsolutions.net>]

On Mon, 2018-06-18 at 14:48 +0530, Balaji Pothunoori wrote:
> On 2018-06-15 17:11, Johannes Berg wrote:
> > On Mon, 2018-06-04 at 19:41 +0530, Balaji Pothunoori wrote:
> > > 
> > > +++ b/include/uapi/linux/nl80211.h
> > > @@ -3000,8 +3000,8 @@ enum nl80211_sta_bss_param {
> > >   *	received from the station (u64, usec)
> > >   * @NL80211_STA_INFO_PAD: attribute used for padding for 64-bit 
> > > alignment
> > >   * @NL80211_STA_INFO_ACK_SIGNAL: signal strength of the last ACK 
> > > frame(u8, dBm)
> > > - * @NL80211_STA_INFO_DATA_ACK_SIGNAL_AVG: avg signal strength of 
> > > (data)
> > > - *	ACK frame (s8, dBm)
> > > + * @NL80211_STA_INFO_ACK_SIGNAL_AVG: avg signal strength of data or 
> > > management
> > > + *	ACK frames(s8, dBm)
> > >   * @__NL80211_STA_INFO_AFTER_LAST: internal
> > >   * @NL80211_STA_INFO_MAX: highest possible station info attribute
> > >   */
> > > @@ -3041,7 +3041,7 @@ enum nl80211_sta_info {
> > >  	NL80211_STA_INFO_RX_DURATION,
> > >  	NL80211_STA_INFO_PAD,
> > >  	NL80211_STA_INFO_ACK_SIGNAL,
> > > -	NL80211_STA_INFO_DATA_ACK_SIGNAL_AVG,
> > > +	NL80211_STA_INFO_ACK_SIGNAL_AVG,
> > 
> > Wait, what happened here? You can't remove old API.
> 
> Here is my intention is to make the unique average ack signal and last 
> ack signal
> support in station dump irrespective of data or management tx ack 
> packet.
> Do you want me to add a new API for management tx ack packet?

Well, you can't remove old API.

And the data-ACK was explicitly added because of concerns about signal
varying a lot with MCS, so ACK signal is more reliable.

I suppose the original use here didn't really *need* just *data* ACK, so
perhaps we can redefine it - you'd know better? After all, you defined
the old API :-))

But still, you can't just remove it. I think we're probably OK to
redefine it but then you need to keep API compatibility by adding the
necessary defines.

johannes