From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754132AbdKITAt (ORCPT ); Thu, 9 Nov 2017 14:00:49 -0500 Received: from esa6.dell-outbound.iphmx.com ([68.232.149.229]:46890 "EHLO esa6.dell-outbound.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752626AbdKITAr (ORCPT ); Thu, 9 Nov 2017 14:00:47 -0500 IronPort-PHdr: =?us-ascii?q?9a23=3AOD3OcBVdGNwxJNm+ObZaWVW7RhTV8LGtZVwlr6E/?= =?us-ascii?q?grcLSJyIuqrYbRKHt8tkgFKBZ4jH8fUM07OQ6PGwHzRYqb+681k6OKRWUBEEjc?= =?us-ascii?q?hE1ycBO+WiTXPBEfjxciYhF95DXlI2t1uyMExSBdqsLwaK+i764jEdAAjwOhRo?= =?us-ascii?q?LerpBIHSk9631+ev8JHPfglEnjSwbLdxIRmssQndqtQdjJd/JKo21hbHuGZDdf?= =?us-ascii?q?5MxWNvK1KTnhL86dm18ZV+7SleuO8v+tBZX6nicKs2UbJXDDI9M2Ao/8LrrgXM?= =?us-ascii?q?TRGO5nQHTGoblAdDDhXf4xH7WpfxtTb6tvZ41SKHM8D6Uaw4VDK/5KptVRTmij?= =?us-ascii?q?oINyQh/W/XlMJ+kb5brhyiqRxxwYHUYZ2aOvVxca7GYdMVXmhBUtpNWyBdAI6x?= =?us-ascii?q?aZYEAeobPeZfqonwv1wDoxykCgm2BePvzSVEiHn33a0/1OQhFx3J3A0+ENIKtH?= =?us-ascii?q?TUq874O7oMXuCxyKnE1ynMb/RT2Trk7oXDbxMvoemUUL9xcsfd01cjGg3bglmK?= =?us-ascii?q?tIDoPzyY2v4JvmWf9+ZsSP6jh3Q6pwx+rDWj3Nogh4rTio8Wy13I7Th1zYk7KN?= =?us-ascii?q?GiVUJ2YN+pHIFTuiyaLYd6XN8uT31utS0n0LMJo4S7czIPyJk/wh7fbOGIfJaQ?= =?us-ascii?q?7xL4UeaRPS94hHV4eLKjnxqy8Vavyun7VsSszllKtTBKn9jWun8QyRPT7syHRu?= =?us-ascii?q?J6/ke8xTaAzAfT6vxCIU8pi6bXMZ8hwqYwlpoWvkXPBDP5mELzjKOOd0Uk/Pan?= =?us-ascii?q?6/j/b7jnpZKQLZF4hw/gPqg0h8CyAes1PhIKUmWf4ei80afs/Uz9QLVElP02la?= =?us-ascii?q?zZvYjdK8sBvK65AghV3pwl5Ra+Cjem19IYkmUGLF1bfBKHi4/pNkrTL//mCfe/?= =?us-ascii?q?h06gnytsx/DDJrHhGInCLmDfkLf9erZw80pcyAs1zdBC6JNYE7IBL+zpWk/3qt?= =?us-ascii?q?PYCgQ0MxK7w+n5EtVxzIAeVnyVAq+fLqzStUWE5uU1I+mDfIUVoiryK+A55/7y?= =?us-ascii?q?in80gUcdfa2z0psLZnC4Ge5mI0CAbXXxmNcBEHkKsRQkTODzh1yPUj9eam2sX6?= =?us-ascii?q?Iz+D47EpiqDYTdSYC3hryOwiO7EodRZmBcBVDfWUvvItGfUusMeSuUK9VogzUC?= =?us-ascii?q?XL7nSJI5zQy1qwb/2pJjL+zJ6msZs47u0J5+4OiF0Vlm+SJ0Bt6B+2CLQXt9km?= =?us-ascii?q?4BS3kxxq8p5QQpw1GPwO5jg/FGHtxe4fBOegg/PJ/Yied9DoahdBjGe4LdbV+8?= =?us-ascii?q?Q9LgJTA0SdQ6wtIKZ0FVF9imilbI2C/8UOxdrKCCGJFhqvGU5HP2Pcsok3s=3D?= X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A2F2AADpnQRah2Oa6ERcGQEBAQEBAQEBA?= =?us-ascii?q?QEBAQcBAQEBAYQIficHg3aKH48ngXyBf4ZXjXiCEQqFOwIahB0/GAEBAQEBAQE?= =?us-ascii?q?BAQECEAEBAQoLCQgoL4I4IoJEAQEBAwEjBA1FDAQCAQgRBAEBAQICIwMCAgIfJ?= =?us-ascii?q?QEICAIEAQ0FCIoDAw0IqVWBbTqHQg2DSAEBAQEBAQEBAQEBAQEBAQEBAQEBAR2?= =?us-ascii?q?BD4IhggeDPYMqgmuCMxAhAoJbgmMFiiKJLY4PPZAFhHCTRI0iiQCBOR+CKnpeg?= =?us-ascii?q?mSCXBAMGYFOd4p5gREBAQE?= X-IPAS-Result: =?us-ascii?q?A2F2AADpnQRah2Oa6ERcGQEBAQEBAQEBAQEBAQcBAQEBAYQ?= =?us-ascii?q?IficHg3aKH48ngXyBf4ZXjXiCEQqFOwIahB0/GAEBAQEBAQEBAQECEAEBAQoLC?= =?us-ascii?q?QgoL4I4IoJEAQEBAwEjBA1FDAQCAQgRBAEBAQICIwMCAgIfJQEICAIEAQ0FCIo?= =?us-ascii?q?DAw0IqVWBbTqHQg2DSAEBAQEBAQEBAQEBAQEBAQEBAQEBAR2BD4IhggeDPYMqg?= =?us-ascii?q?muCMxAhAoJbgmMFiiKJLY4PPZAFhHCTRI0iiQCBOR+CKnpegmSCXBAMGYFOd4p?= =?us-ascii?q?5gREBAQE?= From: X-LoopCount0: from 10.166.132.187 X-IronPort-AV: E=Sophos;i="5.44,370,1505797200"; d="scan'208";a="574121690" X-DLP: DLP_GlobalPCIDSS To: , , CC: , , Subject: RE: [PATCH v2 2/2] platform/x86: dell-*wmi*: Relay failed initial probe to dependent drivers Thread-Topic: [PATCH v2 2/2] platform/x86: dell-*wmi*: Relay failed initial probe to dependent drivers Thread-Index: AQHTWYu9jkIOuaHstE2lyVVVv1NNI6MMZe8Q Date: Thu, 9 Nov 2017 19:00:45 +0000 Message-ID: References: <2080bee9a4c98164498aa32c4f10b12bc50b183d.1510246939.git.mario.limonciello@dell.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.143.18.86] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id vA9J0sXV001889 > -----Original Message----- > From: platform-driver-x86-owner@vger.kernel.org [mailto:platform-driver-x86- > owner@vger.kernel.org] On Behalf Of sathyanarayanan kuppuswamy > Sent: Thursday, November 9, 2017 12:51 PM > To: Limonciello, Mario ; dvhart@infradead.org; > Andy Shevchenko > Cc: LKML ; platform-driver-x86@vger.kernel.org; > pali.rohar@gmail.com > Subject: Re: [PATCH v2 2/2] platform/x86: dell-*wmi*: Relay failed initial probe to > dependent drivers > > Hi, > > > On 11/09/2017 09:49 AM, Mario Limonciello wrote: > > dell-wmi and dell-smbios-wmi are dependent upon dell-wmi-descriptor > > finishing probe successfully to probe themselves. > if they are dependent, then why not control the device creation of > dell-wmi and dell-smbios-wmi drivers in del-wmi-descriptor probe ? The dependency is just in a function call that dell-wmi-descriptor provides information to the other drivers. Each of these is a driver that binds to a GUID on the WMI bus. They can each be built/configured independently of one another and also independently bound or unbound to a GUID on the WMI bus. Since these are bus drivers, the WMI bus will control creation of devices when probe routines are run. > > > Currently if dell-wmi-descriptor fails probing in a non-recoverable way > > (such as invalid header) dell-wmi and dell-smbios-wmi will continue to > > try to redo probing due to deferred probing. > > > > To solve this have the dependent drivers query the dell-wmi-descriptor > > driver whether the descriptor has been determined valid. The possible > > results are: > > -ENODEV: Descriptor GUID missing from WMI bus > > -EPROBE_DEFER: Descriptor not yet probed, dependent driver should wait > > and use deferred probing > > < 0: Descriptor probed, invalid. Dependent driver should return an > > error. > > 0: Successful descriptor probe, dependent driver can continue > > > > Successful descriptor probe still doesn't mean that the descriptor driver > > is necessarily bound at the time of initialization of dependent driver. > > Userspace can unbind the driver, so all methods used from driver > > should still be verified to return success values otherwise deferred > > probing be used. > > > > Signed-off-by: Mario Limonciello > > --- > > drivers/platform/x86/dell-smbios-wmi.c | 5 +++-- > > drivers/platform/x86/dell-wmi-descriptor.c | 16 ++++++++++++++++ > > drivers/platform/x86/dell-wmi-descriptor.h | 8 +++++++- > > drivers/platform/x86/dell-wmi.c | 6 ++++-- > > 4 files changed, 30 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell- > smbios-wmi.c > > index 35c13815b24c..ca556803c8c9 100644 > > --- a/drivers/platform/x86/dell-smbios-wmi.c > > +++ b/drivers/platform/x86/dell-smbios-wmi.c > > @@ -148,8 +148,9 @@ static int dell_smbios_wmi_probe(struct wmi_device > *wdev) > > int count; > > int ret; > > > > - if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID)) > > - return -ENODEV; > > + ret = dell_wmi_get_descriptor_valid(); > > + if (ret) > > + return ret; > > > > priv = devm_kzalloc(&wdev->dev, sizeof(struct wmi_smbios_priv), > > GFP_KERNEL); > > diff --git a/drivers/platform/x86/dell-wmi-descriptor.c > b/drivers/platform/x86/dell-wmi-descriptor.c > > index 28ef5f37cfbf..4dfef1f53481 100644 > > --- a/drivers/platform/x86/dell-wmi-descriptor.c > > +++ b/drivers/platform/x86/dell-wmi-descriptor.c > > @@ -21,14 +21,26 @@ > > #include > > #include "dell-wmi-descriptor.h" > > > > +#define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012- > B622A1EF5492" > > + > > struct descriptor_priv { > > struct list_head list; > > u32 interface_version; > > u32 size; > > }; > > +static int descriptor_valid = -EPROBE_DEFER; > > static LIST_HEAD(wmi_list); > > static DEFINE_MUTEX(list_mutex); > > > > +int dell_wmi_get_descriptor_valid(void) > > +{ > > + if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID)) > > + return -ENODEV; > > + > > + return descriptor_valid; > > +} > > +EXPORT_SYMBOL_GPL(dell_wmi_get_descriptor_valid); > > + > > bool dell_wmi_get_interface_version(u32 *version) > > { > > struct descriptor_priv *priv; > > @@ -91,6 +103,7 @@ static int dell_wmi_descriptor_probe(struct wmi_device > *wdev) > > if (obj->type != ACPI_TYPE_BUFFER) { > > dev_err(&wdev->dev, "Dell descriptor has wrong type\n"); > > ret = -EINVAL; > > + descriptor_valid = ret; > > goto out; > > } > > > > @@ -102,6 +115,7 @@ static int dell_wmi_descriptor_probe(struct wmi_device > *wdev) > > "Dell descriptor buffer has unexpected length (%d)\n", > > obj->buffer.length); > > ret = -EINVAL; > > + descriptor_valid = ret; > > goto out; > > } > > > > @@ -111,8 +125,10 @@ static int dell_wmi_descriptor_probe(struct wmi_device > *wdev) > > dev_err(&wdev->dev, "Dell descriptor buffer has invalid signature > (%8ph)\n", > > buffer); > > ret = -EINVAL; > > + descriptor_valid = ret; > > goto out; > > } > > + descriptor_valid = 0; > > > > if (buffer[2] != 0 && buffer[2] != 1) > > dev_warn(&wdev->dev, "Dell descriptor buffer has unknown > version (%lu)\n", > > diff --git a/drivers/platform/x86/dell-wmi-descriptor.h > b/drivers/platform/x86/dell-wmi-descriptor.h > > index 5f7b69c2c83a..1e8cb96ffd78 100644 > > --- a/drivers/platform/x86/dell-wmi-descriptor.h > > +++ b/drivers/platform/x86/dell-wmi-descriptor.h > > @@ -13,7 +13,13 @@ > > > > #include > > > > -#define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012- > B622A1EF5492" > > +/* possible return values: > > + * -ENODEV: Descriptor GUID missing from WMI bus > > + * -EPROBE_DEFER: probing for dell-wmi-descriptor not yet run > > + * 0: valid descriptor, successfully probed > > + * < 0: invalid descriptor, don't probe dependent devices > > + */ > > +int dell_wmi_get_descriptor_valid(void); > > > > bool dell_wmi_get_interface_version(u32 *version); > > bool dell_wmi_get_size(u32 *size); > > diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c > > index 54321080a30d..39d2f4518483 100644 > > --- a/drivers/platform/x86/dell-wmi.c > > +++ b/drivers/platform/x86/dell-wmi.c > > @@ -655,9 +655,11 @@ static int dell_wmi_events_set_enabled(bool enable) > > static int dell_wmi_probe(struct wmi_device *wdev) > > { > > struct dell_wmi_priv *priv; > > + int ret; > > > > - if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID)) > > - return -ENODEV; > > + ret = dell_wmi_get_descriptor_valid(); > > + if (ret) > > + return ret; > > > > priv = devm_kzalloc( > > &wdev->dev, sizeof(struct dell_wmi_priv), GFP_KERNEL); > > -- > Sathyanarayanan Kuppuswamy > Linux kernel developer