Re: [PATCH] carl9170: fix bad rssi reading

Re: [PATCH] carl9170: fix bad rssi reading

[Christian Lamparter]

On Thursday, September 10, 2015 06:04:45 PM Hiroaki KAWAI wrote:
> Fix rssi calculation error which was introduced in otus to ar9170
> porting.
> 
> Signed-off-by: Hiroaki KAWAI <hiroaki.kawai@gmail.com>
Acked-by: Christian Lamparter <chunkeey@googlemail.com>

For reference: Here's the line in the original otus code:
<http://lxr.free-electrons.com/source/drivers/staging/otus/hal/hpusb.c?v=2.6.33#L818>

This value/result isn't used anywhere, so we could also remove it. 

> ---
>  drivers/net/wireless/ath/carl9170/rx.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/ath/carl9170/rx.c b/drivers/net/wireless/ath/carl9170/rx.c
> index 924135b..d66533c 100644
> --- a/drivers/net/wireless/ath/carl9170/rx.c
> +++ b/drivers/net/wireless/ath/carl9170/rx.c
> @@ -453,7 +453,7 @@ static void carl9170_rx_phy_status(struct ar9170 *ar,
>  	/* post-process RSSI */
>  	for (i = 0; i < 7; i++)
>  		if (phy->rssi[i] & 0x80)
> -			phy->rssi[i] = ((phy->rssi[i] & 0x7f) + 1) & 0x7f;
> +			phy->rssi[i] = ((~phy->rssi[i] & 0x7f) + 1) & 0x7f;
>  
>  	/* TODO: we could do something with phy_errors */
>  	status->signal = ar->noise[0] + phy->rssi_combined;
> 

Re: [PATCH] carl9170: fix bad rssi reading

[Hiroaki Kawai]

That field is union and referenced as rssi_combined at two lines below.

The status->signal will show up in radiotap IEEE80211_RADIOTAP_DBM_ANTSIGNAL
header field at userland finally.

2015-09-10 22:07 GMT+09:00 Christian Lamparter <chunkeey@googlemail.com>:
> On Thursday, September 10, 2015 06:04:45 PM Hiroaki KAWAI wrote:
>> Fix rssi calculation error which was introduced in otus to ar9170
>> porting.
>>
>> Signed-off-by: Hiroaki KAWAI <hiroaki.kawai@gmail.com>
> Acked-by: Christian Lamparter <chunkeey@googlemail.com>
>
> For reference: Here's the line in the original otus code:
> <http://lxr.free-electrons.com/source/drivers/staging/otus/hal/hpusb.c?v=2.6.33#L818>
>
> This value/result isn't used anywhere, so we could also remove it.
>
>> ---
>>  drivers/net/wireless/ath/carl9170/rx.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/wireless/ath/carl9170/rx.c b/drivers/net/wireless/ath/carl9170/rx.c
>> index 924135b..d66533c 100644
>> --- a/drivers/net/wireless/ath/carl9170/rx.c
>> +++ b/drivers/net/wireless/ath/carl9170/rx.c
>> @@ -453,7 +453,7 @@ static void carl9170_rx_phy_status(struct ar9170 *ar,
>>       /* post-process RSSI */
>>       for (i = 0; i < 7; i++)
>>               if (phy->rssi[i] & 0x80)
>> -                     phy->rssi[i] = ((phy->rssi[i] & 0x7f) + 1) & 0x7f;
>> +                     phy->rssi[i] = ((~phy->rssi[i] & 0x7f) + 1) & 0x7f;
>>
>>       /* TODO: we could do something with phy_errors */
>>       status->signal = ar->noise[0] + phy->rssi_combined;
>>
>

Re: [PATCH] carl9170: fix bad rssi reading

[Christian Lamparter]

On Friday, September 11, 2015 01:37:48 AM Hiroaki Kawai wrote:
> That field is union and referenced as rssi_combined at two lines below.
Correct

> The status->signal will show up in radiotap
> IEEE80211_RADIOTAP_DBM_ANTSIGNAL
> header field at userland finally.

so, this patch should go to -stable too.

Cc: stable@vger.kernel.org

Thanks
> > > ---
> > >  drivers/net/wireless/ath/carl9170/rx.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/net/wireless/ath/carl9170/rx.c
> > b/drivers/net/wireless/ath/carl9170/rx.c
> > > index 924135b..d66533c 100644
> > > --- a/drivers/net/wireless/ath/carl9170/rx.c
> > > +++ b/drivers/net/wireless/ath/carl9170/rx.c
> > > @@ -453,7 +453,7 @@ static void carl9170_rx_phy_status(struct ar9170 *ar,
> > >       /* post-process RSSI */
> > >       for (i = 0; i < 7; i++)
> > >               if (phy->rssi[i] & 0x80)
> > > -                     phy->rssi[i] = ((phy->rssi[i] & 0x7f) + 1) & 0x7f;
> > > +                     phy->rssi[i] = ((~phy->rssi[i] & 0x7f) + 1) & 0x7f;
> > >
> > >       /* TODO: we could do something with phy_errors */
> > >       status->signal = ar->noise[0] + phy->rssi_combined;
> > >
> >
> >

[PATCH] carl9170: fix bad rssi reading

[Hiroaki KAWAI]

Fix rssi calculation error which was introduced in otus to ar9170
porting.

Signed-off-by: Hiroaki KAWAI <hiroaki.kawai@gmail.com>
---
 drivers/net/wireless/ath/carl9170/rx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/carl9170/rx.c b/drivers/net/wireless/ath/carl9170/rx.c
index 924135b..d66533c 100644
--- a/drivers/net/wireless/ath/carl9170/rx.c
+++ b/drivers/net/wireless/ath/carl9170/rx.c
@@ -453,7 +453,7 @@ static void carl9170_rx_phy_status(struct ar9170 *ar,
 	/* post-process RSSI */
 	for (i = 0; i < 7; i++)
 		if (phy->rssi[i] & 0x80)
-			phy->rssi[i] = ((phy->rssi[i] & 0x7f) + 1) & 0x7f;
+			phy->rssi[i] = ((~phy->rssi[i] & 0x7f) + 1) & 0x7f;
 
 	/* TODO: we could do something with phy_errors */
 	status->signal = ar->noise[0] + phy->rssi_combined;
-- 
2.5.1

Re: carl9170: fix bad rssi reading

[Kalle Valo]

> Fix rssi calculation error which was introduced in otus to ar9170
> porting.
> 
> Signed-off-by: Hiroaki KAWAI <hiroaki.kawai@gmail.com>
> Acked-by: Christian Lamparter <chunkeey@googlemail.com>

Thanks, applied to wireless-drivers-next.git.

Kalle Valo