xref: /OK3568_Linux_fs/kernel/Documentation/ABI/testing/sysfs-bus-amba (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunWhat:		/sys/bus/amba/devices/.../driver_override
2*4882a593SmuzhiyunDate:		September 2014
3*4882a593SmuzhiyunContact:	Antonios Motakis <a.motakis@virtualopensystems.com>
4*4882a593SmuzhiyunDescription:
5*4882a593Smuzhiyun		This file allows the driver for a device to be specified which
6*4882a593Smuzhiyun		will override standard OF, ACPI, ID table, and name matching.
7*4882a593Smuzhiyun		When specified, only a driver with a name matching the value
8*4882a593Smuzhiyun		written to driver_override will have an opportunity to bind to
9*4882a593Smuzhiyun		the device. The override is specified by writing a string to the
10*4882a593Smuzhiyun		driver_override file (echo vfio-amba > driver_override)	and may
11*4882a593Smuzhiyun		be cleared with an empty string (echo > driver_override).
12*4882a593Smuzhiyun		This returns the device to standard matching rules binding.
13*4882a593Smuzhiyun		Writing to driver_override does not automatically unbind the
14*4882a593Smuzhiyun		device from its current driver or make any attempt to
15*4882a593Smuzhiyun		automatically load the specified driver. If no driver with a
16*4882a593Smuzhiyun		matching name is currently loaded in the kernel, the device will
17*4882a593Smuzhiyun		not bind to any driver. This also allows devices to opt-out of
18*4882a593Smuzhiyun		driver binding using a driver_override name such as "none".
19*4882a593Smuzhiyun		Only a single driver may be specified in the override, there is
20*4882a593Smuzhiyun		no support for parsing delimiters.
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