Re: [PATCH] mac80211: Fix power save state stuck in ACTIVE caused by race between suspend and Tx packet.

[Krishna Chaitanya <chaitanya.mgit@gmail.com>]

On Sun, May 31, 2015 at 3:52 PM, Chaitanya T K <chaitanya.mgit@gmail.com> wrote:
> From: Chaitanya T K <chaitanya.mgit@gmail.com>
>
> If we receive suspend after TX path has executed
> dynamic ps disable work, the driver will be in
> ACTIVE state during suspend and even after it
> resumes.
>
> As before suspend all data packets are flushed
> it is safe to put the driver in to sleep for
> optimal power during suspend or up on resume.
>
> Signed-off-by: Chaitanya T K <chaitanya.mgit@gmail.com>
> ---
>  net/mac80211/pm.c |   15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
> index ac6ad62..c9d71c2 100644
> --- a/net/mac80211/pm.c
> +++ b/net/mac80211/pm.c
> @@ -76,6 +76,21 @@ int __ieee80211_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan)
>                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
>                                 continue;
>                         ieee80211_mgd_quiesce(sdata);
> +                       /* This is to handle a race where suspend
> +                        * is invoked after dynamic ps work disables
> +                        * power save due to TX. This causes the driver
> +                        * to be stuck in ACTIVE during suspend and
> +                        * after resume unless there is another TX,
> +                        * after which the dynamic ps puts driver
> +                        * back to DOZE.
> +                        */
> +                       if (sdata->u.mgd.associated &&
> +                           sdata->u.mgd.powersave &&
> +                            !(local->hw.conf.flags & IEEE80211_CONF_PS)) {
> +                               local->hw.conf.flags |= IEEE80211_CONF_PS;
> +                               ieee80211_hw_config(local,
> +                                                   IEEE80211_CONF_CHANGE_PS);
> +                       }
>                 }
>
>                 err = drv_suspend(local, wowlan);


Johannes,

I was final able to fix my "from" problem in git send-email.
Sorry for previous spamming. We can continue the discussion
in this thread.

Regards,
Chaitanya T K>


-- 
Thanks,
Regards,
Chaitanya T K.