kernel/linux.git/include/linux/device.h, branch v5.10.258

driver core: Move dev_err_probe() to where it belogs

2026-06-01T15:29:36+00:00

[ Upstream commit 9e0cace7a6254070159ebd86497eadc29ea307ca ] dev_err_probe() belongs to the printing API, hence move the definition from device.h to dev_printk.h. There is no change to the callers at all, since: 1) implementation is located in the same core.c; 2) dev_printk.h is guaranteed to be included by device.h. Signed-off-by: Andy Shevchenko Reviewed-by: Andi Shyti Link: https://lore.kernel.org/r/20230721131309.16821-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 797cc011ae02 ("backlight: sky81452-backlight: Check return value of devm_gpiod_get_optional() in sky81452_bl_parse_dt()") Signed-off-by: Sasha Levin

driver core: device.h: remove extern from function prototypes

2026-06-01T15:29:36+00:00

[ Upstream commit f43243c66e5e9ad839d235f82a58e73a7e7612af ] The kernel coding style does not require 'extern' in function prototypes in .h files, so remove them from include/linux/device.h as they are not needed. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230324122711.2664537-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 797cc011ae02 ("backlight: sky81452-backlight: Check return value of devm_gpiod_get_optional() in sky81452_bl_parse_dt()") Signed-off-by: Sasha Levin

driver core: Add kernel-doc for DEV_FLAG_COUNT enum value

2026-06-01T15:29:21+00:00

commit 5b484311507b5d403c1f7a45f6aa3778549e268b upstream. Even though nobody should use this value (except when declaring the "flags" bitmap), kernel-doc still gets upset that it's not documented. It reports: WARNING: ../include/linux/device.h:519 Enum value 'DEV_FLAG_COUNT' not described in enum 'struct_device_flags' Add the description of DEV_FLAG_COUNT. Fixes: a2225b6e834a ("driver core: Don't let a device probe until it's ready") Reported-by: Randy Dunlap Closes: https://lore.kernel.org/f318cd43-81fd-48b9-abf7-92af85f12f91@infradead.org Signed-off-by: Douglas Anderson Tested-by: Randy Dunlap Reviewed-by: Randy Dunlap Link: https://patch.msgid.link/20260413195910.1.I23aca74fe2d3636a47df196a80920fecb2643220@changeid Signed-off-by: Danilo Krummrich Signed-off-by: Greg Kroah-Hartman

driver core: Don't let a device probe until it's ready

2026-06-01T15:29:18+00:00

[ Upstream commit a2225b6e834a838ae3c93709760edc0a169eb2f2 ] The moment we link a "struct device" into the list of devices for the bus, it's possible probe can happen. This is because another thread can load the driver at any time and that can cause the device to probe. This has been seen in practice with a stack crawl that looks like this [1]: really_probe() __driver_probe_device() driver_probe_device() __driver_attach() bus_for_each_dev() driver_attach() bus_add_driver() driver_register() __platform_driver_register() init_module() [some module] do_one_initcall() do_init_module() load_module() __arm64_sys_finit_module() invoke_syscall() As a result of the above, it was seen that device_links_driver_bound() could be called for the device before "dev->fwnode->dev" was assigned. This prevented __fw_devlink_pickup_dangling_consumers() from being called which meant that other devices waiting on our driver's sub-nodes were stuck deferring forever. It's believed that this problem is showing up suddenly for two reasons: 1. Android has recently (last ~1 year) implemented an optimization to the order it loads modules [2]. When devices opt-in to this faster loading, modules are loaded one-after-the-other very quickly. This is unlike how other distributions do it. The reproduction of this problem has only been seen on devices that opt-in to Android's "parallel module loading". 2. Android devices typically opt-in to fw_devlink, and the most noticeable issue is the NULL "dev->fwnode->dev" in device_links_driver_bound(). fw_devlink is somewhat new code and also not in use by all Linux devices. Even though the specific symptom where "dev->fwnode->dev" wasn't assigned could be fixed by moving that assignment higher in device_add(), other parts of device_add() (like the call to device_pm_add()) are also important to run before probe. Only moving the "dev->fwnode->dev" assignment would likely fix the current symptoms but lead to difficult-to-debug problems in the future. Fix the problem by preventing probe until device_add() has run far enough that the device is ready to probe. If somehow we end up trying to probe before we're allowed, __driver_probe_device() will return -EPROBE_DEFER which will make certain the device is noticed. In the race condition that was seen with Android's faster module loading, we will temporarily add the device to the deferred list and then take it off immediately when device_add() probes the device. Instead of adding another flag to the bitfields already in "struct device", instead add a new "flags" field and use that. This allows us to freely change the bit from different thread without worrying about corrupting nearby bits (and means threads changing other bit won't corrupt us). [1] Captured on a machine running a downstream 6.6 kernel [2] https://cs.android.com/android/platform/superproject/main/+/main:system/core/libmodprobe/libmodprobe.cpp?q=LoadModulesParallel Cc: stable@vger.kernel.org Fixes: 2023c610dc54 ("Driver core: add new device to bus's list before probing") Reviewed-by: Alan Stern Reviewed-by: Rafael J. Wysocki (Intel) Reviewed-by: Danilo Krummrich Acked-by: Greg Kroah-Hartman Acked-by: Marek Szyprowski Signed-off-by: Douglas Anderson Link: https://patch.msgid.link/20260406162231.v5.1.Id750b0fbcc94f23ed04b7aecabcead688d0d8c17@changeid Signed-off-by: Danilo Krummrich Signed-off-by: Douglas Anderson Signed-off-by: Sasha Levin

locking: Introduce __cleanup() based infrastructure

2025-10-29T13:01:15+00:00

[ Upstream commit 54da6a0924311c7cf5015533991e44fb8eb12773 ] Use __attribute__((__cleanup__(func))) to build: - simple auto-release pointers using __free() - 'classes' with constructor and destructor semantics for scope-based resource management. - lock guards based on the above classes. Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

driver core/PM: Set power.no_callbacks along with power.no_pm

2025-10-29T13:01:03+00:00

commit c2ce2453413d429e302659abc5ace634e873f6f5 upstream. Devices with power.no_pm set are not expected to need any power management at all, so modify device_set_pm_not_required() to set power.no_callbacks for them too in case runtime PM will be enabled for any of them (which in principle may be done for convenience if such a device participates in a dependency chain). Since device_set_pm_not_required() must be called before device_add() or it would not have any effect, it can update power.no_callbacks without locking, unlike pm_runtime_no_callbacks() that can be called after registering the target device. Signed-off-by: Rafael J. Wysocki Cc: stable Reviewed-by: Sudeep Holla Link: https://lore.kernel.org/r/1950054.tdWV9SEqCh@rafael.j.wysocki Signed-off-by: Greg Kroah-Hartman

driver core: Introduce device_find_any_child() helper

2024-12-14T18:47:56+00:00

[ Upstream commit 82b070beae1ef55b0049768c8dc91d87565bb191 ] There are several places in the kernel where this kind of functionality is being used. Provide a generic helper for such cases. Reviewed-by: Rafael J. Wysocki Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220610120219.18988-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 27aabf27fd01 ("Bluetooth: fix use-after-free in device_for_each_child()") Signed-off-by: Sasha Levin

driver core: Introduce device_link_wait_removal()

2024-04-13T10:59:34+00:00

commit 0462c56c290a99a7f03e817ae5b843116dfb575c upstream. The commit 80dd33cf72d1 ("drivers: base: Fix device link removal") introduces a workqueue to release the consumer and supplier devices used in the devlink. In the job queued, devices are release and in turn, when all the references to these devices are dropped, the release function of the device itself is called. Nothing is present to provide some synchronisation with this workqueue in order to ensure that all ongoing releasing operations are done and so, some other operations can be started safely. For instance, in the following sequence: 1) of_platform_depopulate() 2) of_overlay_remove() During the step 1, devices are released and related devlinks are removed (jobs pushed in the workqueue). During the step 2, OF nodes are destroyed but, without any synchronisation with devlink removal jobs, of_overlay_remove() can raise warnings related to missing of_node_put(): ERROR: memory leak, expected refcount 1 instead of 2 Indeed, the missing of_node_put() call is going to be done, too late, from the workqueue job execution. Introduce device_link_wait_removal() to offer a way to synchronize operations waiting for the end of devlink removals (i.e. end of workqueue jobs). Also, as a flushing operation is done on the workqueue, the workqueue used is moved from a system-wide workqueue to a local one. Cc: stable@vger.kernel.org Signed-off-by: Herve Codina Tested-by: Luca Ceresoli Reviewed-by: Nuno Sa Reviewed-by: Saravana Kannan Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20240325152140.198219-2-herve.codina@bootlin.com Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

driver core: Move the "removable" attribute from USB to core

2023-12-08T07:46:15+00:00

[ Upstream commit 70f400d4d957c2453c8689552ff212bc59f88938 ] Move the "removable" attribute from USB to core in order to allow it to be supported by other subsystem / buses. Individual buses that want to support this attribute can populate the removable property of the device while enumerating it with the 3 possible values - - "unknown" - "fixed" - "removable" Leaving the field unchanged (i.e. "not supported") would mean that the attribute would not show up in sysfs for that device. The UAPI (location, symantics etc) for the attribute remains unchanged. Move the "removable" attribute from USB to the device core so it can be used by other subsystems / buses. By default, devices do not have a "removable" attribute in sysfs. If a subsystem or bus driver wants to support a "removable" attribute, it should call device_set_removable() before calling device_register() or device_add(), e.g.: device_set_removable(dev, DEVICE_REMOVABLE); device_register(dev); The possible values and the resulting sysfs attribute contents are: DEVICE_REMOVABLE_UNKNOWN -> "unknown" DEVICE_REMOVABLE -> "removable" DEVICE_FIXED -> "fixed" Convert the USB "removable" attribute to use this new device core functionality. There should be no user-visible change in the location or semantics of attribute for USB devices. Reviewed-by: Bjorn Helgaas Signed-off-by: Rajat Jain Link: https://lore.kernel.org/r/20210524171812.18095-1-rajatja@google.com Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 432e664e7c98 ("drm/amdgpu: don't use ATRM for external devices") Signed-off-by: Sasha Levin

driver core: add a helper to setup both the of_node and fwnode of a device

2023-05-30T11:57:45+00:00

[ Upstream commit 43e76d463c09a0272b84775bcc727c1eb8b384b2 ] There are many places where both the fwnode_handle and the of_node of a device need to be populated. Add a function which does both so that we have consistency. Suggested-by: Andrew Lunn Signed-off-by: Ioana Ciornei Reviewed-by: Greg Kroah-Hartman Signed-off-by: David S. Miller Stable-dep-of: a26cc2934331 ("drm/mipi-dsi: Set the fwnode for mipi_dsi_device") Signed-off-by: Sasha Levin