kernel/linux.git/drivers/usb/roles/class.c, branch v6.6.134

usb: roles: get usb role switch from parent only for usb-b-connector

2026-03-25T10:05:49+00:00

commit 8345b1539faa49fcf9c9439c3cbd97dac6eca171 upstream. usb_role_switch_is_parent() was walking up to the parent node and checking for the "usb-role-switch" property regardless of the type of the passed fwnode. This could cause unrelated device nodes to be probed as potential role switch parent, leading to spurious matches and "-EPROBE_DEFER" being returned infinitely. Till now only Type-B connector node will have a parent node which may present "usb-role-switch" property and register the role switch device. For Type-C connector node, its parent node will always be a Type-C chip device which will never register the role switch device. However, it may still present a non-boolean "usb-role-switch = <&usb_controller>" property for historical compatibility. So restrict the helper to only operate on Type-B connector when attempting to get the role switch from parent node. Fixes: 6fadd72943b8 ("usb: roles: get usb-role-switch from parent") Cc: stable Signed-off-by: Xu Yang Tested-by: Arnaud Ferraris Reviewed-by: Heikki Krogerus Link: https://patch.msgid.link/20260309074313.2809867-3-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

usb: roles: set switch registered flag early on

2025-02-21T12:57:14+00:00

commit 634775a752a86784511018a108f3b530cc3399a7 upstream. The role switch registration and set_role() can happen in parallel as they are invoked independent of each other. There is a possibility that a driver might spend significant amount of time in usb_role_switch_register() API due to the presence of time intensive operations like component_add() which operate under common mutex. This leads to a time window after allocating the switch and before setting the registered flag where the set role notifications are dropped. Below timeline summarizes this behavior Thread1 | Thread2 usb_role_switch_register() | | | ---> allocate switch | | | ---> component_add() | usb_role_switch_set_role() | | | | | --> Drop role notifications | | since sw->registered | | flag is not set. | | --->Set registered flag.| To avoid this, set the registered flag early on in the switch register API. Fixes: b787a3e78175 ("usb: roles: don't get/set_role() when usb_role_switch is unregistered") Cc: stable Signed-off-by: Elson Roy Serrao Reviewed-by: Heikki Krogerus Link: https://lore.kernel.org/r/20250206193950.22421-1-quic_eserrao@quicinc.com Signed-off-by: Greg Kroah-Hartman

usb: roles: don't get/set_role() when usb_role_switch is unregistered

2024-03-01T12:35:02+00:00

commit b787a3e781759026a6212736ef8e52cf83d1821a upstream. There is a possibility that usb_role_switch device is unregistered before the user put usb_role_switch. In this case, the user may still want to get/set_role() since the user can't sense the changes of usb_role_switch. This will add a flag to show if usb_role_switch is already registered and avoid unwanted behaviors. Fixes: fde0aa6c175a ("usb: common: Small class for USB role switches") cc: stable@vger.kernel.org Signed-off-by: Xu Yang Acked-by: Heikki Krogerus Link: https://lore.kernel.org/r/20240129093739.2371530-2-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

usb: roles: fix NULL pointer issue when put module's reference

2024-03-01T12:35:02+00:00

commit 1c9be13846c0b2abc2480602f8ef421360e1ad9e upstream. In current design, usb role class driver will get usb_role_switch parent's module reference after the user get usb_role_switch device and put the reference after the user put the usb_role_switch device. However, the parent device of usb_role_switch may be removed before the user put the usb_role_switch. If so, then, NULL pointer issue will be met when the user put the parent module's reference. This will save the module pointer in structure of usb_role_switch. Then, we don't need to find module by iterating long relations. Fixes: 5c54fcac9a9d ("usb: roles: Take care of driver module reference counting") cc: stable@vger.kernel.org Signed-off-by: Xu Yang Acked-by: Heikki Krogerus Link: https://lore.kernel.org/r/20240129093739.2371530-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

USB: roles: make role_class a static const structure

2023-06-20T14:20:40+00:00

Now that the driver core allows for struct class to be in read-only memory, move the role_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at load time. Suggested-by: Greg Kroah-Hartman Signed-off-by: Ivan Orlov Link: https://lore.kernel.org/r/20230620094412.508580-7-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: class: remove module * from class_create()

2023-03-17T14:16:33+00:00

The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" Acked-by: Benjamin Tissoires Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: make struct device_type.uevent() take a const *

2023-01-27T12:45:36+00:00

The uevent() callback in struct device_type should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Alan Stern Cc: Andreas Noever Cc: Andy Shevchenko Cc: Bard Liao Cc: Chaitanya Kulkarni Cc: Dan Williams Cc: Dmitry Torokhov Cc: Frank Rowand Cc: Ira Weiny Cc: Jason Gunthorpe Cc: Jens Axboe Cc: Jilin Yuan Cc: Jiri Slaby Cc: Len Brown Cc: Mark Gross Cc: "Martin K. Petersen" Cc: "Matthew Wilcox (Oracle)" Cc: Maximilian Luz Cc: Michael Jamet Cc: Ming Lei Cc: Pierre-Louis Bossart Cc: Rob Herring Cc: Sakari Ailus Cc: Sanyog Kale Cc: Sean Young Cc: Stefan Richter Cc: Thomas Gleixner Cc: Won Chung Cc: Yehezkel Bernat Acked-by: Rafael J. Wysocki Acked-by: Mika Westerberg # for Thunderbolt Acked-by: Mauro Carvalho Chehab Acked-by: Alexandre Belloni Acked-by: Heikki Krogerus Acked-by: Wolfram Sang Acked-by: Vinod Koul Acked-by: Hans de Goede Link: https://lore.kernel.org/r/20230111113018.459199-6-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2022-12-16T11:54:54+00:00

Pull driver core updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems" * tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits) device property: Fix documentation for fwnode_get_next_parent() firmware_loader: fix up to_fw_sysfs() to preserve const usb.h: take advantage of container_of_const() device.h: move kobj_to_dev() to use container_of_const() container_of: add container_of_const() that preserves const-ness of the pointer driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion. driver core: fix up missed scsi/cxlflash class.devnode() conversion. driver core: fix up some missing class.devnode() conversions. driver core: make struct class.devnode() take a const * driver core: make struct class.dev_uevent() take a const * cacheinfo: Remove of_node_put() for fw_token device property: Add a blank line in Kconfig of tests device property: Rename goto label to be more precise device property: Move PROPERTY_ENTRY_BOOL() a bit down device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*() kernfs: fix all kernel-doc warnings and multiple typos driver core: pass a const * into of_device_uevent() kobject: kset_uevent_ops: make name() callback take a const * kobject: kset_uevent_ops: make filter() callback take a const * kobject: make kobject_namespace take a const * ...

usb: roles: fix of node refcount leak in usb_role_switch_is_parent()

2022-11-29T07:56:08+00:00

I got the following report while doing device(mt6370-tcpc) load test with CONFIG_OF_UNITTEST and CONFIG_OF_DYNAMIC enabled: OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /i2c/pmic@34 The 'parent' returned by fwnode_get_parent() with refcount incremented. it needs be put after using. Fixes: 6fadd72943b8 ("usb: roles: get usb-role-switch from parent") Reviewed-by: Heikki Krogerus Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20221122111226.251588-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman

device property: Constify fwnode connection match APIs

2022-10-22T11:49:55+00:00

The fwnode and device parameters are not altered in the fwnode connection match APIs, constify them. Signed-off-by: Andy Shevchenko Acked-by: Heikki Krogerus Reviewed-by: Sakari Ailus Link: https://lore.kernel.org/r/20221004092129.19412-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman