On Wed, 2013-12-18 at 17:03 -0800, Greg Kroah-Hartman wrote: > 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 <kim.phillips@xxxxxxxxxx> > > --- > > 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. How is userspace broken? vfio platform is a new thing; there's nothing existing to break. I don't see how automatic module loading makes sense for it. Whether the module needs to be loaded depends on the user's intentions, not based on what hardware you have. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
