From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932262AbcLHLGX (ORCPT ); Thu, 8 Dec 2016 06:06:23 -0500 Received: from mga05.intel.com ([192.55.52.43]:65511 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751845AbcLHLGV (ORCPT ); Thu, 8 Dec 2016 06:06:21 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,319,1477983600"; d="asc'?scan'208";a="40162364" From: Felipe Balbi To: Baolin Wang Cc: mathias.nyman@intel.com, Greg KH , Mark Brown , USB , LKML Subject: Re: [PATCH v4 2/2] usb: dwc3: core: Support the dwc3 host suspend/resume In-Reply-To: References: <5e67c4a6680bbc7c02e92305d81eda5449b8a4af.1479991143.git.baolin.wang@linaro.org> <87oa0mkbd6.fsf@linux.intel.com> Date: Thu, 08 Dec 2016 13:02:04 +0200 Message-ID: <87d1h2k7kj.fsf@linux.intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Hi, Baolin Wang writes: >>> On 28 November 2016 at 14:43, Baolin Wang wrot= e: >>>> For some mobile devices with strict power management, we also want to = suspend >>>> the host when the slave is detached for power saving. Thus we add the = host >>>> suspend/resume functions to support this requirement. >>>> >>>> Signed-off-by: Baolin Wang >>>> --- >>>> Changes since v3: >>>> - No updates. >>>> >>>> Changes since v2: >>>> - Remove pm_children_suspended() and other unused macros. >>>> >>>> Changes since v1: >>>> - Add pm_runtime.h head file to avoid kbuild error. >>>> --- >>>> drivers/usb/dwc3/Kconfig | 7 +++++++ >>>> drivers/usb/dwc3/core.c | 26 +++++++++++++++++++++++++- >>>> drivers/usb/dwc3/core.h | 15 +++++++++++++++ >>>> drivers/usb/dwc3/host.c | 37 +++++++++++++++++++++++++++++++++++++ >>>> 4 files changed, 84 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig >>>> index a45b4f1..47bb2f3 100644 >>>> --- a/drivers/usb/dwc3/Kconfig >>>> +++ b/drivers/usb/dwc3/Kconfig >>>> @@ -47,6 +47,13 @@ config USB_DWC3_DUAL_ROLE >>>> >>>> endchoice >>>> >>>> +config USB_DWC3_HOST_SUSPEND >>>> + bool "Choose if the DWC3 host (xhci) can be suspend/resume" >>>> + depends on USB_DWC3_HOST=3Dy || USB_DWC3_DUAL_ROLE=3Dy >> >> why do you need another Kconfig for this? Just enable it already :-p > > I assume some platforms may do not need this feature. But okay, I can > remove this kconfig and enable it. thanks :-) >>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c >>>> index 9a4a5e4..7ad4bc3 100644 >>>> --- a/drivers/usb/dwc3/core.c >>>> +++ b/drivers/usb/dwc3/core.c >>>> @@ -1091,6 +1091,7 @@ static int dwc3_probe(struct platform_device *pd= ev) >>>> pm_runtime_use_autosuspend(dev); >>>> pm_runtime_set_autosuspend_delay(dev, DWC3_DEFAULT_AUTOSUSPEND= _DELAY); >>>> pm_runtime_enable(dev); >>>> + pm_suspend_ignore_children(dev, true); >> >> why do you need this? > > Since the dwc3 device is the parent deive of xhci device, if we want > to suspend dwc3 device, we need to suspend child device (xhci device) > manually by issuing pm_runtime_put_sync() in dwc3_host_suspend(). In > pm_runtime_put_sync(), it will check if the children (xhci device) of > dwc3 device have been in suspend state, if not we will suspend dwc3 > device failed. > > We get/put the child device manually in parent device's runtime > callback, we need to ignore the child device's runtime state, or it > will failed due to the dependency. I see. Good explanation :-) There's one thing though, if you want to runtime suspend the gadget and dwc3 is working on peripheral mode, host side (XHCI) should already be runtime suspended because there's nothing attached to it. Why isn't it runtime suspended? =2D-=20 balbi --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEElLzh7wn96CXwjh2IzL64meEamQYFAlhJPawACgkQzL64meEa mQYXIhAApfDLJfimh5zffTMs5oNSrnEVPQBwd2EW4iC2AgBAB+zA3oemXNtT8qQy xqXQRAh6Xm4WVgalboytLD8oVhN/4tgFGn6P2iCNqiLQd4j3g7oNYj3OZwdw1IhE /3G4Ve2sFOF+/VDO5V76mcjaav6fVGP3mLwZnRSO5Z7IwHeMraKWNQNIhztVJJMS d06QIk7lZI+3dHNYdGtME0rPU7FVSPCPdk5OC8UwDiPYttW5/FYh9R2c/1kODW0K 7BDL67fqvoeALilYWpFBMiuWmRWExuQ/Wl08T01zThF3n0ij1TBetvA+FkTMfMyp xOIiaBx2oZvpu96hemZlqhvXSxjExo4B3aeqxz2b/CuiGJhePf41QeTdoenHjlpl 1Beg0ueQ6JfqqQHugNW+DEMI/zBrvxtlky8MQFFtwCDS9a0MJV19NjP8RLiugng5 0XJ5UptrlvzZP5HIgyhNXDsiqdkGkkwW5MK5GBcmM+5BWaAzfUZ2avkEdPzax1Yf RGRxQtW+yOGEXwFxBtQVrMnaw4RK6Qv1fK6qKMxndjas/XrEEXPM0YYpvcWMAftT pIEyV6z4vySZYHym6DxUX/M759a3TZ7moJf/IECCnqzRulPmrFJ1iSv2u/1tK1xA RaA0ytzVo7apCZmss1oppQxoH+haVxrzys9aYwpiFZoKX9ONrdg= =2uA7 -----END PGP SIGNATURE----- --=-=-=--