On Thu, Nov 3, 2016 at 12:51 PM, Emmanuel Grumbach <egrumbach@xxxxxxxxx> wrote:
> On Thu, Nov 3, 2016 at 11:59 AM, Felix Fietkau <nbd@xxxxxxxx> wrote:
>> Commit c68df2e7be0c ("mac80211: allow using AP_LINK_PS with
>> mac80211-generated TIM IE") introduced a logic error, where
>> __sta_info_recalc_tim turns into a no-op if local->ops->set_tim is not
>> set. This prevents the beacon TIM bit from being set for all drivers
>> that do not implement this op (almost all of them), thus thoroughly
>> essential AP mode powersave functionality.
>>
>> Cc: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
>> Fixes: c68df2e7be0c ("mac80211: allow using AP_LINK_PS with mac80211-generated TIM IE")
>> Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
>> ---
>> net/mac80211/sta_info.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
>> index 236d47e..621734e 100644
>> --- a/net/mac80211/sta_info.c
>> +++ b/net/mac80211/sta_info.c
>> @@ -688,7 +688,7 @@ static void __sta_info_recalc_tim(struct sta_info *sta, bool ignore_pending)
>> }
>>
>> /* No need to do anything if the driver does all */
>> - if (!local->ops->set_tim)
>> + if (local->ops->set_tim)
>> return;
>
> but ... then, you'll need call to drv_set_tim below...
s/need/never/
> Apparently, we can't rely on the ops pointer to enter or not enter this flow.
