lkml.org 
[lkml]   [2023]   [Jul]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH V7 4/9] wifi: mac80211: Add support for ACPI WBRF
Date
[AMD Official Use Only - General]

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@amd.com>
> Sent: Monday, July 24, 2023 9:41 PM
> To: Andrew Lunn <andrew@lunn.ch>; Quan, Evan <Evan.Quan@amd.com>
> Cc: rafael@kernel.org; lenb@kernel.org; Deucher, Alexander
> <Alexander.Deucher@amd.com>; Koenig, Christian
> <Christian.Koenig@amd.com>; Pan, Xinhui <Xinhui.Pan@amd.com>;
> airlied@gmail.com; daniel@ffwll.ch; johannes@sipsolutions.net;
> davem@davemloft.net; edumazet@google.com; kuba@kernel.org;
> pabeni@redhat.com; mdaenzer@redhat.com;
> maarten.lankhorst@linux.intel.com; tzimmermann@suse.de;
> hdegoede@redhat.com; jingyuwang_vip@163.com; Lazar, Lijo
> <Lijo.Lazar@amd.com>; jim.cromie@gmail.com; bellosilicio@gmail.com;
> andrealmeid@igalia.com; trix@redhat.com; jsg@jsg.id.au; arnd@arndb.de;
> linux-kernel@vger.kernel.org; linux-acpi@vger.kernel.org; amd-
> gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; linux-
> wireless@vger.kernel.org; netdev@vger.kernel.org
> Subject: Re: [PATCH V7 4/9] wifi: mac80211: Add support for ACPI WBRF
>
> On 7/24/2023 04:22, Andrew Lunn wrote:
> >> @@ -1395,6 +1395,8 @@ int ieee80211_register_hw(struct
> ieee80211_hw *hw)
> >> debugfs_hw_add(local);
> >> rate_control_add_debugfs(local);
> >>
> >> + ieee80211_check_wbrf_support(local);
> >> +
> >> rtnl_lock();
> >> wiphy_lock(hw->wiphy);
> >>
> >
> >> +void ieee80211_check_wbrf_support(struct ieee80211_local *local) {
> >> + struct wiphy *wiphy = local->hw.wiphy;
> >> + struct device *dev;
> >> +
> >> + if (!wiphy)
> >> + return;
> >> +
> >> + dev = wiphy->dev.parent;
> >> + if (!dev)
> >> + return;
> >> +
> >> + local->wbrf_supported = wbrf_supported_producer(dev);
> >> + dev_dbg(dev, "WBRF is %s supported\n",
> >> + local->wbrf_supported ? "" : "not"); }
> >
> > This seems wrong. wbrf_supported_producer() is about "Should this
> > device report the frequencies it is using?" The answer to that depends
> > on a combination of: Are there consumers registered with the core, and
> > is the policy set so WBRF should take actions. > The problem here is,
> > you have no idea of the probe order. It could be this device probes
> > before others, so wbrf_supported_producer() reports false, but a few
> > second later would report true, once other devices have probed.
> >
> > It should be an inexpensive call into the core, so can be made every
> > time the channel changes. All the core needs to do is check if the
> > list of consumers is empty, and if not, check a Boolean policy value.
> >
> > Andrew
>
> No, it's not a combination of whether consumers are registered with the core.
> If a consumer probes later it needs to know the current in use frequencies too.
>
> The reason is because of this sequence of events:
> 1) Producer probes.
> 2) Producer selects a frequency.
> 3) Consumer probes.
> 4) Producer stays at same frequency.
>
> If the producer doesn't notify the frequency because a consumer isn't yet
> loaded then the consumer won't be able to get the current frequency.
Yes, exactly.
\
 
 \ /
  Last update: 2023-07-25 12:39    [W:0.121 / U:0.456 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site