Re: [RFC 4/6] ath9k: add DFS build parameter

["Luis R. Rodriguez" <rodrigue@qca.qualcomm.com>]

On Tue, Oct 4, 2011 at 3:37 AM, Felix Fietkau <nbd@openwrt.org> wrote:
> On 2011-10-04 11:55 AM, Zefir Kurtisi wrote:
>>
>> On 10/03/2011 08:26 PM, Luis R. Rodriguez wrote:
>>>
>>>  On Mon, Oct 3, 2011 at 3:29 AM, Zefir Kurtisi<zefir.kurtisi@neratec.com>
>>>  wrote:
>>>>
>>>>  Signed-off-by: Zefir Kurtisi<zefir.kurtisi@neratec.com>
>>>>  ---
>>>>  drivers/net/wireless/ath/ath9k/Kconfig  |    7 +++++++
>>>>  drivers/net/wireless/ath/ath9k/Makefile |    2 ++
>>>>  2 files changed, 9 insertions(+), 0 deletions(-)
>>>>
>>>>  diff --git a/drivers/net/wireless/ath/ath9k/Kconfig
>>>> b/drivers/net/wireless/ath/ath9k/Kconfig
>>>>  index d9c08c6..adddcca 100644
>>>>  --- a/drivers/net/wireless/ath/ath9k/Kconfig
>>>>  +++ b/drivers/net/wireless/ath/ath9k/Kconfig
>>>>  @@ -58,6 +58,13 @@ config ATH9K_RATE_CONTROL
>>>>          Say Y, if you want to use the ath9k specific rate control
>>>>          module instead of minstrel_ht.
>>>>
>>>>  +config ATH9K_DFS
>>>>  +       bool "Atheros ath9k DFS support"
>>>>  +       depends on ATH9K
>>>>  +       default y
>>>
>>>  At this point selecting y does nothing. Leave this patch out until
>>>  selecting "y" means something.
>>>
>> What do you mean by 'nothing'? It allows you to select DFS as ath9k
>> feature in your kernel configuration, or? Though, I agree that enabling it
>> by default is not a good idea.
>>
>>>  Default should be n, and in particular Atheros itself can only likely
>>>  commit to supporting DFS for AR9003 when it finds resources to do so
>>>  as well as properly test it, so DFS support kconfig should state this.
>>>  If someone wants to step up to completely support all bugs for older
>>>  families that is their prerogative but we cannot commit to it, due to
>>>  the regulatory considerations though unless this happens this cannot
>>>  and should not be enabled for older families in code.
>>>
>> In fact, AR9003 is the platform we are interested in. Although it
>> seems that older chipsets do also detect pulses with this patches
>> (AR9280 does, IIRC), I agree to limit DFS support to AR9003 (and later).
>> This should be easily possible by setting priv_ops->set_radar_params for
>> AR9003 only. I'll remove it for AR5008 in my v2 RFC.
>
> Please don't remove support code for older hardware. I'm fine with adding a
> SREV check that prevents it from being enabled by default on older hardware,
> but eventually I will need at least AR9280 DFS support for a few devices in
> OpenWrt.

That's fine, leaving it disabled is what I meant, and only once
something has been properly tested do we enable it. I personally only
want to spend my own energy on AR9003 and newer.

  Luis