Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Felipe Balbi <balbi@kernel.org>
To:     Roger Quadros <rogerq@ti.com>, Baolin Wang <baolin.wang@linaro.org>
Cc:     USB <linux-usb@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] usb: dwc3: Prevent indefinite sleep in _dwc3_set_mode during suspend/resume
In-Reply-To: <f8edc87c-919f-46ab-f437-303dede74c82@ti.com>
References: <1519730526-22274-1-git-send-email-rogerq@ti.com> <87sh9l5z4l.fsf@linux.intel.com> <94cd6377-1327-2309-8d69-6ab0de2bdfd4@ti.com> <87po4i3o1v.fsf@linux.intel.com> <a907787a-dea2-5f15-3d25-693680a42b71@ti.com> <CAMz4kuKOnAPckX1=nqVPyF7O5u-0YrekTfMddYwe0WC2-0AFDw@mail.gmail.com> <87k1uq3ho6.fsf@linux.intel.com> <8ec0485e-89af-568b-e34a-b0cd490817d0@ti.com> <CAMz4kuJpBXY92zhG7s_VRkpcTHeLCE_vBLLSFVxLWjN2GQvyyw@mail.gmail.com> <87h8puwyn5.fsf@linux.intel.com> <5bc56ef5-66b1-d40c-1639-e748fe18cdbd@ti.com> <87muzha9h4.fsf@linux.intel.com> <f8edc87c-919f-46ab-f437-303dede74c82@ti.com>
Date:   Fri, 09 Mar 2018 12:36:58 +0200
Message-ID: <87h8ppa62d.fsf@linux.intel.com>
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="=-=-=";
        micalg=pgp-sha512; protocol="application/pgp-signature"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

--=-=-=
Content-Type: text/plain
Content-Transfer-Encoding: quoted-printable


Hi,

Roger Quadros <rogerq@ti.com> writes:
>>> This is what the v3.10 databook says
>>>
>>> "When issuing an End Transfer command, software must set the CmdIOC
>>> bit (field 8) so that an Endpoint Command Complete event is generated
>>> after the transfer ends. This is necessary to synchronize the
>>> conclusion of system bus traffic before the End Transfer command is
>>> completed."
>>>
>>> with a note
>>>
>>> "If GUCTL2[Rst_actbitlater] is set, Software can poll the completion
>>> of the End Transfer command by polling the command active bit to be
>>> cleared to 0."
>>>
>>> fyi.
>>>
>>> Rst_actbitlater - "Enable clearing of the command active bit for the
>>> ENDXFER command after the command execution is completed.  This bit is
>>> valid in device mode only."
>>>
>>> So I'd prefer not to clear CMDIOC for all cases.
>>>
>>> Could we some how just tackle the dwc3_gadget_exit case like I did in
>>> this patch?
>>=20
>> if you can send a version that doesn't iterate over all endpoints twice,
>> sure. We still need a comment somewhere, and I fear we may get
>> interrupts later in some cases. How would we deal with that?
>>=20
>
> how about explicitly masking that interrupt? Is it possible?

I think I showed that the bit is reserved on recent dwc3 core releases
(anytyhing 2.40a+, at least).

=2D-=20
balbi

--=-=-=
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----
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=V937
-----END PGP SIGNATURE-----
--=-=-=--