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Date:   Wed, 29 Jun 2022 19:34:58 +0200
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arve =?utf-8?B?SGrDuG5uZXbDpWc=?= <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Christian Brauner <brauner@kernel.org>,
        Hridya Valsaraju <hridya@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Theodore Ts'o <tytso@mit.edu>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>,
        Paolo Abeni <pabeni@redhat.com>, Rob Herring <robh@kernel.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
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Subject: Re: [PATCH] remove CONFIG_ANDROID
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On Wed, Jun 29, 2022 at 06:38:09PM +0200, Jason A. Donenfeld wrote:
> On the technical topic, an Android developer friend following this
> thread just pointed out to me that Android doesn't use PM_AUTOSLEEP and
> just has userspace causing suspend frequently. So by his rough
> estimation your patch actually *will* break Android devices. Zoinks.
> Maybe he's right, maybe he's not -- I don't know -- but you should
> probably look into this if you want this patch to land without breakage.

More details: https://cs.android.com/android/platform/superproject/+/master:system/core/libsuspend/autosuspend_wakeup_count.cpp;bpv=1;bpt=1;l=52?q=%22%2Fsys%2Fpower%2Fstate%22&start=51&gsn=sys_power_state&gs=kythe%3A%2F%2Fandroid.googlesource.com%2Fplatform%2Fsuperproject%3Flang%3Dc%252B%252B%3Fpath%3Dsystem%2Fcore%2Flibsuspend%2Fautosuspend_wakeup_count.cpp%23ftWlDJuOhS_2fn3Ri7rClxA30blj_idGgT12aoUHd1o

So indeed it looks like it's userspace controlled. If you want this to
be a runtime, rather than a compiletime, switch, maybe
autosuspend_init() of that file could write to a sysctl.

Who at Google "owns" that code? Can somebody CC them in?

Jason