From 3d713e0e382e6fcfb4bba1501645b66c129ad60b Mon Sep 17 00:00:00 2001 From: Kim Phillips Date: Mon, 2 Jun 2014 19:42:58 -0500 Subject: driver core: platform: add device binding path 'driver_override' Needed by platform device drivers, such as the upcoming vfio-platform driver, in order to bypass the existing OF, ACPI, id_table and name string matches, and successfully be able to be bound to any device, like so: echo vfio-platform > /sys/bus/platform/devices/fff51000.ethernet/driver_override echo fff51000.ethernet > /sys/bus/platform/devices/fff51000.ethernet/driver/unbind echo fff51000.ethernet > /sys/bus/platform/drivers_probe This mimics "PCI: Introduce new device binding path using pci_dev.driver_override", which is an interface enhancement for more deterministic PCI device binding, e.g., when in the presence of hotplug. Reviewed-by: Alex Williamson Reviewed-by: Alexander Graf Reviewed-by: Stuart Yoder Signed-off-by: Kim Phillips Signed-off-by: Greg Kroah-Hartman --- Documentation/ABI/testing/sysfs-bus-platform | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-platform (limited to 'Documentation/ABI') diff --git a/Documentation/ABI/testing/sysfs-bus-platform b/Documentation/ABI/testing/sysfs-bus-platform new file mode 100644 index 000000000000..5172a6124b27 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-platform @@ -0,0 +1,20 @@ +What: /sys/bus/platform/devices/.../driver_override +Date: April 2014 +Contact: Kim Phillips +Description: + This file allows the driver for a device to be specified which + will override standard OF, ACPI, ID table, and name matching. + When specified, only a driver with a name matching the value + written to driver_override will have an opportunity to bind + to the device. The override is specified by writing a string + to the driver_override file (echo vfio-platform > \ + driver_override) and may be cleared with an empty string + (echo > driver_override). This returns the device to standard + matching rules binding. Writing to driver_override does not + automatically unbind the device from its current driver or make + any attempt to automatically load the specified driver. If no + driver with a matching name is currently loaded in the kernel, + the device will not bind to any driver. This also allows + devices to opt-out of driver binding using a driver_override + name such as "none". Only a single driver may be specified in + the override, there is no support for parsing delimiters. -- cgit v1.2.3