user/sven/linux.git/include/linux/usb.h, branch v6.2-rc5

USB: fix misleading usb_set_intfdata() kernel doc

2023-01-17T16:39:13Z

The struct device driver-data pointer is used for any data that a driver may need in various callbacks while bound to the device. For convenience, subsystems typically provide wrappers such as usb_set_intfdata() of the generic accessor functions for use in bus callbacks. There is generally no longer any need for a driver to clear the pointer, but since commit 0998d0631001 ("device-core: Ensure drvdata = NULL when no driver is bound") the driver-data pointer is set to NULL by driver core post unbind anyway. For historical reasons, USB core also clears this pointer when an explicitly claimed interface is released. Due to a misunderstanding, a misleading kernel doc comment for usb_set_intfdata() was recently added which claimed that the driver data pointer must not be cleared during disconnect before "all actions [are] completed", which is both imprecise and incorrect. Specifically, drivers like cdc-acm which claim additional interfaces use the driver-data pointer as a flag which is cleared when the first interface is unbound. As long as a driver does not do something odd like dereference the pointer in, for example, completion callbacks, this can be done at any time during disconnect. And in any case this is no different than for any other resource, like the driver data itself, which may be freed by the disconnect callback. Note that the comment actually also claimed that the interface itself was somehow being set to NULL by driver core. Fix the kernel doc by removing incorrect, overly specific and misleading details and adding a comment about why some drivers do clear the driver-data pointer. Fixes: 27ef17849779 ("usb: add usb_set_intfdata() documentation") Signed-off-by: Johan Hovold Acked-by: Alan Stern Acked-by: Vincent Mailhol Link: https://lore.kernel.org/r/20221212152035.31806-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

usb: acpi: add helper to check port lpm capability using acpi _DSM

2023-01-17T15:37:24Z

Add a helper to evaluate ACPI usb device specific method (_DSM) provided in case the USB3 port shouldn't enter U1 and U2 link states. This _DSM was added as port specific retimer configuration may lead to exit latencies growing beyond U1/U2 exit limits, and OS needs a way to find which ports can't support U1/U2 link power management states. This _DSM is also used by windows: Link: https://docs.microsoft.com/en-us/windows-hardware/drivers/bringup/usb-device-specific-method---dsm- Some patch issues found in testing resolved by Ron Lee Cc: stable@vger.kernel.org Tested-by: Ron Lee Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20230116142216.1141605-7-mathias.nyman@linux.intel.com 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

2022-12-16T11:54:54Z

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 * ...

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

2022-12-16T11:22:53Z

Pull USB and Thunderbolt driver updates from Greg KH: "Here is the large set of USB and Thunderbolt driver changes for 6.2-rc1. Overall, thanks to the removal of a driver, more lines were removed than added, a nice change. Highlights include: - removal of the sisusbvga driver that was not used by anyone anymore - minor thunderbolt driver changes and tweaks - chipidea driver updates - usual set of typec driver features and hardware support added - musb minor driver fixes - fotg210 driver fixes, bringing that hardware back from the "dead" - minor dwc3 driver updates - addition, and then removal, of a list.h helper function for many USB and other subsystem drivers, that ended up breaking the build. That will come back for 6.3-rc1, it missed this merge window. - usual xhci updates and enhancements - usb-serial driver updates and support for new devices - other minor USB driver updates All of these have been in linux-next for a while with no reported problems" * tag 'usb-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (153 commits) usb: gadget: uvc: Rename bmInterfaceFlags -> bmInterlaceFlags usb: dwc2: power on/off phy for peripheral mode in dual-role mode usb: dwc2: disable lpm feature on Rockchip SoCs dt-bindings: usb: mtk-xhci: add support for mt7986 usb: dwc3: core: defer probe on ulpi_read_id timeout usb: ulpi: defer ulpi_register on ulpi_read_id timeout usb: misc: onboard_usb_hub: add Genesys Logic GL850G hub support dt-bindings: usb: Add binding for Genesys Logic GL850G hub controller dt-bindings: vendor-prefixes: add Genesys Logic usb: fotg210-udc: fix potential memory leak in fotg210_udc_probe() usb: typec: tipd: Set mode of operation for USB Type-C connector usb: gadget: udc: drop obsolete dependencies on COMPILE_TEST usb: musb: remove extra check in musb_gadget_vbus_draw usb: gadget: uvc: Prevent buffer overflow in setup handler usb: dwc3: qcom: Fix memory leak in dwc3_qcom_interconnect_init usb: typec: wusb3801: fix fwnode refcount leak in wusb3801_probe() usb: storage: Add check for kcalloc USB: sisusbvga: use module_usb_driver() USB: sisusbvga: rename sisusb.c to sisusbvga.c USB: sisusbvga: remove console support ...

USB: core: export usb_cache_string()

2022-12-12T10:39:12Z

usb_cache_string() can also be useful for the drivers so export it. Signed-off-by: Vincent Mailhol Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/all/20221130174658.29282-4-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde

usb.h: take advantage of container_of_const()

2022-12-06T15:55:25Z

Instead of rolling our own const-checking logic in to_usb_interface() and to_usb_device() use the newly added container_of_const() instead, making the logic much simpler overall. Reviewed-by: Sakari Ailus Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20221205121206.166576-3-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

usb: add usb_set_intfdata() documentation

2022-11-29T07:56:09Z

USB drivers do not need to call usb_set_intfdata(intf, NULL) in their usb_driver::disconnect callback because the core already does it in [1]. However, this fact is widely unknown, c.f.: $ git grep "usb_set_intfdata(.*NULL)" | wc -l 215 Especially, setting the interface to NULL before all action completed can result in a NULL pointer dereference. Not calling usb_set_intfdata() at all in disconnect() is the safest method. Add documentation to usb_set_intfdata() to clarify this point. Also remove the call in usb-skeletion's disconnect() not to confuse the new comers. [1] function usb_unbind_interface() from drivers/usb/core/driver.c Link: https://elixir.bootlin.com/linux/v6.0/source/drivers/usb/core/driver.c#L497 Signed-off-by: Vincent Mailhol Link: https://lore.kernel.org/r/20221128102954.3615579-1-mailhol.vincent@wanadoo.fr Signed-off-by: Greg Kroah-Hartman

USB: make devnode() callback in usb_class_driver take a const *

2022-10-20T10:11:56Z

With the changes to the driver core to make more pointers const, the USB subsystem also needs to be modified to take a const * for the devnode callback so that the driver core's constant pointer will also be properly propagated. Cc: Benjamin Tissoires Cc: Juergen Stuber Reviewed-by: Johan Hovold Acked-by: Pete Zaitcev Reviewed-by: Jiri Kosina Link: https://lore.kernel.org/r/20221001165128.2688526-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

USB: allow some usb functions to take a const pointer.

2022-10-20T10:05:33Z

The functions to_usb_interface(), to_usb_device, and interface_to_usbdev() sometimes would like to take a const * and return a const * back. As we are doing pointer math, a call to container_of() loses the const-ness of a pointer, so use a _Generic() macro to pick the proper inline function to call instead. Link: https://lore.kernel.org/r/20221016104155.1260201-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

USB: core: Prevent nested device-reset calls

2022-08-30T13:32:04Z

Automatic kernel fuzzing revealed a recursive locking violation in usb-storage: ============================================ WARNING: possible recursive locking detected 5.18.0 #3 Not tainted -------------------------------------------- kworker/1:3/1205 is trying to acquire lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 but task is already holding lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 ... stack backtrace: CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747 usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109 r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622 usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:545 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:537 __device_release_driver drivers/base/dd.c:1222 [inline] device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248 usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627 usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118 usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114 This turned out not to be an error in usb-storage but rather a nested device reset attempt. That is, as the rtl8712 driver was being unbound from a composite device in preparation for an unrelated USB reset (that driver does not have pre_reset or post_reset callbacks), its ->remove routine called usb_reset_device() -- thus nesting one reset call within another. Performing a reset as part of disconnect processing is a questionable practice at best. However, the bug report points out that the USB core does not have any protection against nested resets. Adding a reset_in_progress flag and testing it will prevent such errors in the future. Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/ Cc: stable@vger.kernel.org Reported-and-tested-by: Rondreis Signed-off-by: Alan Stern Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman