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+What: /sys/class/devlink/.../
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ Provide a place in sysfs for the device link objects in the
+ kernel at any given time. The name of a device link directory,
+ denoted as ... above, is of the form <supplier>--<consumer>
+ where <supplier> is the supplier bus:device name and <consumer>
+ is the consumer bus:device name.
+
+What: /sys/class/devlink/.../auto_remove_on
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ This file indicates if the device link will ever be
+ automatically removed by the driver core when the consumer and
+ supplier devices themselves are still present.
+
+ This will be one of the following strings:
+
+ - 'consumer unbind'
+ - 'supplier unbind'
+ - 'never'
+
+ 'consumer unbind' means the device link will be removed when
+ the consumer's driver is unbound from the consumer device.
+
+ 'supplier unbind' means the device link will be removed when
+ the supplier's driver is unbound from the supplier device.
+
+ 'never' means the device link will not be automatically removed
+ when as long as the supplier and consumer devices themselves
+ are still present.
+
+What: /sys/class/devlink/.../consumer
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ This file is a symlink to the consumer device's sysfs directory.
+
+What: /sys/class/devlink/.../runtime_pm
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ This file indicates if the device link has any impact on the
+ runtime power management behavior of the consumer and supplier
+ devices. For example: Making sure the supplier doesn't enter
+ runtime suspend while the consumer is active.
+
+ This will be one of the following strings:
+
+ === ========================================
+ '0' Does not affect runtime power management
+ '1' Affects runtime power management
+ === ========================================
+
+What: /sys/class/devlink/.../status
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ This file indicates the status of the device link. The status
+ of a device link is affected by whether the supplier and
+ consumer devices have been bound to their corresponding
+ drivers. The status of a device link also affects the binding
+ and unbinding of the supplier and consumer devices with their
+ drivers and also affects whether the software state of the
+ supplier device is synced with the hardware state of the
+ supplier device after boot up.
+ See also: sysfs-devices-state_synced.
+
+ This will be one of the following strings:
+
+ - 'not tracked'
+ - 'dormant'
+ - 'available'
+ - 'consumer probing'
+ - 'active'
+ - 'supplier unbinding'
+ - 'unknown'
+
+ 'not tracked' means this device link does not track the status
+ and has no impact on the binding, unbinding and syncing the
+ hardware and software device state.
+
+ 'dormant' means the supplier and the consumer devices have not
+ bound to their driver.
+
+ 'available' means the supplier has bound to its driver and is
+ available to supply resources to the consumer device.
+
+ 'consumer probing' means the consumer device is currently
+ trying to bind to its driver.
+
+ 'active' means the supplier and consumer devices have both
+ bound successfully to their drivers.
+
+ 'supplier unbinding' means the supplier devices is currently in
+ the process of unbinding from its driver.
+
+ 'unknown' means the state of the device link is not any of the
+ above. If this is ever the value, there's a bug in the kernel.
+
+What: /sys/class/devlink/.../supplier
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ This file is a symlink to the supplier device's sysfs directory.
+
+What: /sys/class/devlink/.../sync_state_only
+Date: May 2020
+Contact: Saravana Kannan <saravanak@google.com>
+Description:
+ This file indicates if the device link is limited to only
+ affecting the syncing of the hardware and software state of the
+ supplier device.
+
+ This will be one of the following strings:
+
+ === ================================
+ '0'
+ '1' Affects runtime power management
+ === ================================
+
+ '0' means the device link can affect other device behaviors
+ like binding/unbinding, suspend/resume, runtime power
+ management, etc.
+
+ '1' means the device link will only affect the syncing of
+ hardware and software state of the supplier device after boot
+ up and doesn't not affect other behaviors of the devices.