kernel/linux.git/include/linux/usb.h, branch v7.0-rc7

usb: core: use dedicated spinlock for offload state

2026-04-02T07:43:26+00:00

Replace the coarse USB device lock with a dedicated offload_lock spinlock to reduce contention during offload operations. Use offload_pm_locked to synchronize with PM transitions and replace the legacy offload_at_suspend flag. Optimize usb_offload_get/put by switching from auto-resume/suspend to pm_runtime_get_if_active(). This ensures offload state is only modified when the device is already active, avoiding unnecessary power transitions. Cc: stable Fixes: ef82a4803aab ("xhci: sideband: add api to trace sideband usage") Signed-off-by: Guan-Yu Lin Tested-by: Hailong Liu Acked-by: Mathias Nyman Link: https://patch.msgid.link/20260401123238.3790062-2-guanyulin@google.com Signed-off-by: Greg Kroah-Hartman

USB: core: Limit the length of unkillable synchronous timeouts

2026-03-11T15:16:56+00:00

The usb_control_msg(), usb_bulk_msg(), and usb_interrupt_msg() APIs in usbcore allow unlimited timeout durations. And since they use uninterruptible waits, this leaves open the possibility of hanging a task for an indefinitely long time, with no way to kill it short of unplugging the target device. To prevent this sort of problem, enforce a maximum limit on the length of these unkillable timeouts. The limit chosen here, somewhat arbitrarily, is 60 seconds. On many systems (although not all) this is short enough to avoid triggering the kernel's hung-task detector. In addition, clear up the ambiguity of negative timeout values by treating them the same as 0, i.e., using the maximum allowed timeout. Signed-off-by: Alan Stern Link: https://lore.kernel.org/linux-usb/3acfe838-6334-4f6d-be7c-4bb01704b33d@rowland.harvard.edu/ Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") CC: stable@vger.kernel.org Link: https://patch.msgid.link/15fc9773-a007-47b0-a703-df89a8cf83dd@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman

USB: usbcore: Introduce usb_bulk_msg_killable()

2026-03-11T15:16:56+00:00

The synchronous message API in usbcore (usb_control_msg(), usb_bulk_msg(), and so on) uses uninterruptible waits. However, drivers may call these routines in the context of a user thread, which means it ought to be possible to at least kill them. For this reason, introduce a new usb_bulk_msg_killable() function which behaves the same as usb_bulk_msg() except for using wait_for_completion_killable_timeout() instead of wait_for_completion_timeout(). The same can be done later for usb_control_msg() later on, if it turns out to be needed. Signed-off-by: Alan Stern Suggested-by: Oliver Neukum Link: https://lore.kernel.org/linux-usb/3acfe838-6334-4f6d-be7c-4bb01704b33d@rowland.harvard.edu/ Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") CC: stable@vger.kernel.org Link: https://patch.msgid.link/248628b4-cc83-4e81-a620-3ce4e0376d41@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman

usb: linux/usb.h: Correct the description of the usb_device_driver member

2025-12-17T13:43:31+00:00

In the current kernel USB device driver code, only the name field is required to be provided; all other fields are optional. Correct this part of the description. Signed-off-by: Yi Cong Acked-by: Alan Stern Link: https://patch.msgid.link/20251202090948.334809-1-cong.yi@linux.dev Signed-off-by: Greg Kroah-Hartman

usb: offload: add apis for offload usage tracking

2025-09-12T12:08:02+00:00

Introduce offload_usage and corresponding apis to track offload usage on each USB device. Offload denotes that there is another co-processor accessing the USB device via the same USB host controller. To optimize power usage, it's essential to monitor whether the USB device is actively used by other co-processor. This information is vital when determining if a USB device can be safely suspended during system power state transitions. Signed-off-by: Guan-Yu Lin Link: https://lore.kernel.org/r/20250911142051.90822-3-guanyulin@google.com Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250911142051.90822-3-guanyulin@google.com

usb: core: Introduce usb_endpoint_is_hs_isoc_double()

2025-09-06T13:25:05+00:00

Introduce usb_endpoint_is_hs_isoc_double() tell whether an endpoint conforms to USB 2.0 Isochronous Double IN Bandwidth ECN. Signed-off-by: Sakari Ailus Acked-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250820143824.551777-7-sakari.ailus@linux.intel.com

usb: core: Add a function to get USB version independent periodic payload

2025-09-06T13:25:05+00:00

Add usb_endpoint_max_periodic_payload() to obtain maximum payload bytes in a service interval for isochronous and interrupt endpoints in a USB version independent way. Signed-off-by: Rai, Amardeep Signed-off-by: Mathias Nyman Co-developed-by: Sakari Ailus Signed-off-by: Sakari Ailus Reviewed-by: Hans de Goede Acked-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250820143824.551777-5-sakari.ailus@linux.intel.com

usb: core: add urb->sgt parameter description

2025-07-21T15:40:02+00:00

The parameter description of urb->sgt is lost, this will add it for completeness. Reported-by: Stephen Rothwell Closes: https://lore.kernel.org/all/20250711182803.1d548467@canb.auug.org.au/ Signed-off-by: Xu Yang Fixes: 488e6eaab88c ("usb: core: add dma-noncoherent buffer alloc and free API") Link: https://lore.kernel.org/r/20250721104417.3442530-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

usb: core: add dma-noncoherent buffer alloc and free API

2025-07-09T10:15:56+00:00

This will add usb_alloc_noncoherent() and usb_free_noncoherent() functions to support alloc and free buffer in a dma-noncoherent way. To explicit manage the memory ownership for the kernel and device, this will also add usb_dma_noncoherent_sync_for_cpu/device() functions and call it at proper time. The management requires the user save sg_table returned by usb_alloc_noncoherent() to urb->sgt. Signed-off-by: Xu Yang Reviewed-by: Alan Stern Link: https://lore.kernel.org/r/20250704095751.73765-2-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

Merge merge point of tag 'usb-6.16-rc5' into usb-next

2025-07-05T05:52:33+00:00

We need the USB fixes in here as well to build on top of for other changes that depend on them. Signed-off-by: Greg Kroah-Hartman