From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [REPOST][PATCH 2/2] driver core: platform: allow platform drivers to bind to any device Date: Wed, 18 Dec 2013 17:03:40 -0800 Message-ID: <20131219010340.GA23055@kroah.com> References: <20131203123454.3ab18749ed0d0d943b10df9a@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, scottwood@freescale.com, R65777@freescale.com, B07421@freescale.com, B08248@freescale.com, christoffer.dall@linaro.org, alex.williamson@redhat.com, a.motakis@virtualopensystems.com, agraf@suse.de, B16395@freescale.com To: Kim Phillips Return-path: Content-Disposition: inline In-Reply-To: <20131203123454.3ab18749ed0d0d943b10df9a@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Tue, Dec 03, 2013 at 12:34:54PM +0000, Kim Phillips wrote: > Platform drivers such as the vfio-platform "meta-" driver [1] > should be allowed to specify that they can bind to any device, > much like PCI drivers can with PCI_ANY_ID. > > Currently, binding platform drivers to devices depends on: > > - a string match in the device node's compatible entry (OF) > - a string match in the ACPI id list (ACPI) > - a string match in the id_table (platform data) > - a string match on the driver name (fall-back) > > none of which allow for the notion of "match any." > > This patch adds the notion by adding a "match any device" boolean to > struct platform_driver, for drivers to be able to set and thus not cause > platform_match() to fail when a bind is requested. > > [1] http://www.spinics.net/lists/kvm/msg96701.html > > Signed-off-by: Kim Phillips > --- > rebased onto 3.13-rc2, and reposted from first submission which > received no comments: > > https://lkml.org/lkml/2013/10/11/48 > > drivers/base/platform.c | 4 ++++ > include/linux/platform_device.h | 1 + > 2 files changed, 5 insertions(+) > > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index 3a94b79..78a5b62 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -736,6 +736,10 @@ static int platform_match(struct device *dev, struct device_driver *drv) > struct platform_device *pdev = to_platform_device(dev); > struct platform_driver *pdrv = to_platform_driver(drv); > > + /* the driver matches any device */ > + if (pdrv->match_any_dev) > + return 1; This breaks userspace in that it will never know to load the module that can "bind to anything". You need a way to encode this in the platform device id that can be a wildcard type of thing, so that userspace can know about this. thanks, greg k-h