Commit fc88bb11 authored by Amit Sunil Dhamne's avatar Amit Sunil Dhamne Committed by Greg Kroah-Hartman
Browse files

usb: roles: add lockdep class key to struct usb_role_switch 



There can be multiple role switch devices running on a platform. Given
that lockdep is not capable of differentiating between locks of
different instances, false positive warnings for circular locking are
reported. To prevent this, register unique lockdep key for each of the
individual instances.

Signed-off-by: default avatarAmit Sunil Dhamne <amitsd@google.com>
Reviewed-by: default avatarBadhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20240822223717.253433-1-amitsd@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4333dbd9

drivers/usb/roles/class.c

+9 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/usb/role.h>

#include <linux/property.h>

#include <linux/device.h>

#include <linux/lockdep.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/slab.h>
@@ -33,6 +34,8 @@ struct usb_role_switch { 
	usb_role_switch_set_t set;

	usb_role_switch_get_t get;

	bool allow_userspace_control;



	struct lock_class_key key;

};



#define to_role_switch(d)	container_of(d, struct usb_role_switch, dev)
@@ -396,6 +399,9 @@ usb_role_switch_register(struct device *parent, 


	sw->registered = true;



	lockdep_register_key(&sw->key);

	lockdep_set_class(&sw->lock, &sw->key);



	/* TODO: Symlinks for the host port and the device controller. */



	return sw;
@@ -412,6 +418,9 @@ void usb_role_switch_unregister(struct usb_role_switch *sw) 
{

	if (IS_ERR_OR_NULL(sw))

		return;



	lockdep_unregister_key(&sw->key);



	sw->registered = false;

	if (dev_fwnode(&sw->dev))

		component_del(&sw->dev, &connector_ops);