DbC is currently only enabled back if it's in configured state during
suspend.
If system is suspended after DbC is enabled, but before the device is
properly enumerated by the host, then DbC would not be enabled back in
resume.
Always enable DbC back in resume if it's suspended in enabled,
connected, or configured state
Cc: stable <stable@kernel.org>
Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
Tested-by: Łukasz Bartosik <ukaszb@chromium.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DbC may add 1024 bogus bytes to the beginneing of the receiving endpoint
if DbC hw triggers a STALL event before any Transfer Blocks (TRBs) for
incoming data are queued, but driver handles the event after it queued
the TRBs.
This is possible as xHCI DbC hardware may trigger spurious STALL transfer
events even if endpoint is empty. The STALL event contains a pointer
to the stalled TRB, and "remaining" untransferred data length.
As there are no TRBs queued yet the STALL event will just point to first
TRB position of the empty ring, with '0' bytes remaining untransferred.
DbC driver is polling for events, and may not handle the STALL event
before /dev/ttyDBC0 is opened and incoming data TRBs are queued.
The DbC event handler will now assume the first queued TRB (length 1024)
has stalled with '0' bytes remaining untransferred, and copies the data
This race situation can be practically mitigated by making sure the event
handler handles all pending transfer events when DbC reaches configured
state, and only then create dev/ttyDbC0, and start queueing transfers.
The event handler can this way detect the STALL events on empty rings
and discard them before any transfers are queued.
This does in practice solve the issue, but still leaves a small possible
gap for the race to trigger.
We still need a way to distinguish spurious STALLs on empty rings with '0'
bytes remaing, from actual STALL events with all bytes transmitted.
Cc: stable <stable@kernel.org>
Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
Tested-by: Łukasz Bartosik <ukaszb@chromium.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Address the naming and usage of the TR Dequeue Pointer mask in the xhci
driver. The Endpoint Context Field at offset 0x08 is defined as follows:
Bit 0 Dequeue Cycle State (DCS)
Bits 3:1 RsvdZ (Reserved and Zero)
Bits 63:4 TR Dequeue Pointer
When extracting the TR Dequeue Pointer for an Endpoint without Streams,
in xhci_handle_cmd_set_deq(), the inverted Dequeue Cycle State mask
(~EP_CTX_CYCLE_MASK) is used, inadvertently including the Reserved bits.
Although bits 3:1 are typically zero, using the incorrect mask could cause
issues.
The existing mask, named "SCTX_DEQ_MASK," is misleading because "SCTX"
implies exclusivity to Stream Contexts, whereas the TR Dequeue Pointer is
applicable to both Stream and non-Stream Contexts.
Rename the mask to "TR_DEQ_PTR_MASK", utilize GENMASK_ULL() macro and use
the mask when handling the TR Dequeue Pointer field.
Function xhci_get_hw_deq() returns the Endpoint Context Field 0x08, either
directly from the Endpoint context or a Stream.
Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250917210726.97100-5-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 28a76fcc4c.
No actual HW bugs are known where Endpoint Context shows Running state
but Stop Endpoint fails repeatedly with Context State Error and leaves
the endpoint state unchanged. Stop Endpoint retries on Running EPs have
been performed since early 2021 with no such issues reported so far.
Trying to handle this hypothetical case brings a more realistic danger:
if Stop Endpoint fails on an endpoint which hasn't yet started after a
doorbell ring and enough latency occurs before this completion event is
handled, the driver may time out and begin removing cancelled TDs from
a running endpoint, even though one more retry would stop it reliably.
Such high latency is rare but not impossible, and removing TDs from a
running endpoint can cause more damage than not giving back a cancelled
URB (which wasn't happening anyway). So err on the side of caution and
revert to the old policy of always retrying if the EP appears running.
[Remove stable tag as we are dealing with theoretical cases -Mathias]
Fixes: 28a76fcc4c ("usb: xhci: Avoid Stop Endpoint retry loop if the endpoint seems Running")
Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250917210726.97100-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allow autosuspend to be used by xhci plat device. For Qualcomm SoCs,
when in host mode, it is intended that the controller goes to suspend
state to save power and wait for interrupts from connected peripheral
to wake it up. This is particularly used in cases where a HID or Audio
device is connected. In such scenarios, the usb controller can enter
auto suspend and resume action after getting interrupts from the
connected device.
Signed-off-by: Krishna Kurapati <krishna.kurapati@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250916120436.3617598-1-krishna.kurapati@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Guan-Yu Lin <guanyulin@google.com> says:
Wesley Cheng and Mathias Nyman's USB offload design enables a
co-processor to handle some USB transfers, potentially allowing the
system to sleep (suspend-to-RAM) and save power. However, Linux's System
Sleep model halts the USB host controller when the main system isn't
managing any USB transfers. To address this, the proposal modifies the
system to recognize offloaded USB transfers and manage power
accordingly. This way, offloaded USB transfers could still happen during
system sleep (Suspend-to-RAM).
This involves two key steps:
1. Transfer Status Tracking: Propose offload_usage and corresponding
apis drivers could track USB transfers on the co-processor, ensuring
the system is aware of any ongoing activity.
2. Power Management Adjustment: Modifications to the USB driver stack
(xhci host controller driver, and USB device drivers) allow the
system to sleep (Suspend-to-RAM) without disrupting co-processor
managed USB transfers. This involves adding conditional checks to
bypass some power management operations in the System Sleep model.
Link: https://lore.kernel.org/r/20250911142051.90822-1-guanyulin@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sharing a USB controller with another entity via xhci-sideband driver
creates power management complexities. To prevent the USB controller
from being inadvertently deactivated while in use by the other entity, a
usage-count based mechanism is implemented. This allows the system to
manage power effectively, ensuring the controller remains available
whenever needed.
In order to maintain full functionality of an offloaded USB devices,
several changes are made within the suspend flow of such devices:
- skip usb_suspend_device() so that the port/hub are still active for
USB transfers via offloaded path.
- not suspending the endpoints which are used by USB interfaces marked
with needs_remote_wakeup. Namely, skip usb_suspend_interface() and
usb_hcd_flush_endpoint() on associated USB interfaces. This reserves a
pending interrupt urb during system suspend for handling the interrupt
transfer, which is necessary since remote wakeup doesn't apply in the
offloaded USB devices when controller is still active.
- not flushing the endpoints of actively offloaded USB devices. Given
that the USB devices is used by another entity, unilaterally flush the
endpoint might lead to unexpected behavior on another entity.
- not suspending the xhci controller. This is done by skipping the
suspend/resume callbacks in the xhci platform driver.
Signed-off-by: Guan-Yu Lin <guanyulin@google.com>
Link: https://lore.kernel.org/r/20250911142051.90822-5-guanyulin@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250911142051.90822-5-guanyulin@google.com
When the system is suspended, USB hot-plugging/unplugging can trigger
wake events of the Tegra USB host controller.
Enable support for USB wake-up events by parsing device-tree to see if
the interrupts for the wake-up events are present and if so configure
those interrupts. Note that if wake-up events are not present, still
allow the USB host controller to probe as normal.
Signed-off-by: Haotien Hsu <haotienh@nvidia.com>
Link: https://lore.kernel.org/r/20250811074558.1062048-5-haotienh@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pending requests will be flushed on disconnect, and the corresponding
TRBs will be turned into No-op TRBs, which are ignored by the xHC
controller once it starts processing the ring.
If the USB debug cable repeatedly disconnects before ring is started
then the ring will eventually be filled with No-op TRBs.
No new transfers can be queued when the ring is full, and driver will
print the following error message:
"xhci_hcd 0000:00:14.0: failed to queue trbs"
This is a normal case for 'in' transfers where TRBs are always enqueued
in advance, ready to take on incoming data. If no data arrives, and
device is disconnected, then ring dequeue will remain at beginning of
the ring while enqueue points to first free TRB after last cancelled
No-op TRB.
s
Solve this by reinitializing the rings when the debug cable disconnects
and DbC is leaving the configured state.
Clear the whole ring buffer and set enqueue and dequeue to the beginning
of ring, and set cycle bit to its initial state.
Cc: stable@vger.kernel.org
Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250902105306.877476-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Decouple allocation of endpoint ring buffer from initialization
of the buffer, and initialization of endpoint context parts from
from the rest of the contexts.
It allows driver to clear up and reinitialize endpoint rings
after disconnect without reallocating everything.
This is a prerequisite for the next patch that prevents the transfer
ring from filling up with cancelled (no-op) TRBs if a debug cable is
reconnected several times without transferring anything.
Cc: stable@vger.kernel.org
Fixes: dfba2174dc ("usb: xhci: Add DbC support in xHCI driver")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250902105306.877476-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sakari Ailus <sakari.ailus@linux.intel.com> says:
This series enables support for eUSB2 Double Isochronous IN Bandwidth UVC
devices specified in 'USB 2.0 Double Isochronous IN Bandwidth' ECN. In
short, it adds support for new integrated USB2 webcams that can send twice
the data compared to conventional USB2 webcams.
These devices are identified by the device descriptor bcdUSB 0x0220 value.
They have an additional eUSB2 Isochronous Endpoint Companion Descriptor,
and a zero max packet size in regular isoc endpoint descriptor. Support
for parsing that new descriptor was added in commit
c749f058b4 ("USB: core: Add eUSB2 descriptor and parsing in USB core")
This series adds support to UVC, USB core, and xHCI to identify eUSB2
double isoc devices, and allow and set proper max packet, iso frame desc
sizes, bytes per interval, and other values in URBs and xHCI endpoint
contexts needed to support the double data rates for eUSB2 double isoc
devices.
since v4:
https://lore.kernel.org/linux-usb/20250812132445.3185026-1-sakari.ailus@linux.intel.com
- New patch: use le16_to_cpu() to access endpoint descriptor's
wMaxPacketSize field, which is an __le16. This isn't a bugfix as the
value was compared to 0.
- New patch: add USB device speed check for eUSB2 isochronous endpoint
companion parsing. The check is then removed from sites checking the
existence of the companion (through companion's bDescriptorType field,
which is non-zero for valid descriptors).
- New patch: do not parse eUSB2 isoc double BW companion descriptor on
interrupt or OUT endpoints. It is not supposed to be found there,
according to the ECN.
- Rename usb_endpoint_max_isoc_bpi() as
usb_endpoint_max_periodic_payload() and move it right after
usb_maxpacket().
- Fixed @ep reference in kernel-doc documentation for
usb_endpoint_max_periodic_payload().
- In usb_endpoint_max_periodic_payload(), call struct usb_device pointer
argument "udev" instead of "dev", to align with naming elsewhere.
- Add support for interrupt endpoints in
usb_endpoint_max_periodic_payload(); eUSB2 double isoc BW is still
limited to isochronous endpoints though.
- In usb_endpoint_max_periodic_payload(), remove the separate case for
USB_SPEED_HIGH as the check is already done in parsing the eUSB isoc
double BW companion, which is checked for.
- New patch: use usb_endpoint_max_periodic_payload() in xHCI driver,
replacing xhci_get_max_esit_payload().
- Check non-zero bDescriptorType field of ep->eusb2_isoc_ep_comp instead
of dwBytesPerInterval value exceeding 3072, where
xhci_eusb2_is_isoc_bw_double() was used. This aligns the checks of eUSB2
isochronous double bandwidth support for an endpoint.
- New patch: introduce usb_endpoint_is_hs_isoc_double() to figure out
whether an endpoint uses isochronous double bandwidth and use the
function in the xHCI driver and the usb core.
xhci_eusb2_is_isoc_bw_double() is dropped, as well as the
MAX_ISOC_XFER_SIZE_HS macro. usb_endpoint_is_hs_isoc_double() also
includes check for bcdUSB == 0x220, to anticipate adding support for
eUSB2V2.
- Merge condition for checking eUSB2 isoc double bw support for
xHCI/endpoint in xhci_get_endpoint_mult().
- Improve comment regarding maximum packet size bits 12:11 in
xhci_get_endpoint_max_burst().
- Aligned subject prefixes with the recent patches to the same files.
since v3:
https://lore.kernel.org/linux-usb/20250807055355.1257029-1-sakari.ailus@linux.intel.com/
- Use spaces in aligning macro body for HCC2_EUSB2_DIC() (1st patch).
- Move usb_endpoint_max_isoc_bpi() to drivers/usb/core/usb.c (3rd patch).
since v2:
https://lore.kernel.org/linux-usb/20250711083413.1552423-1-sakari.ailus@linux.intel.com
- Use ep->eusb2_isoc_ep_comp.bDescriptorType to determined whether the
eUSB2 isochronous endpoint companion descriptor exists.
- Clean up eUSB2 double isoc bw maxp calculation.
- Drop le16_to_cpu(udev->descriptor.bcdUSB) == 0x220 check from
xhci_eusb2_is_isoc_bw_double() -- it's redundant as
ep->eusb2_isoc_ep_comp.dwBytesPerInterval will be zero otherwise.
- Add kernel-doc documentation for usb_endpoint_max_isoc_bpi().
- Check the endpoint has IN direction in usb_endpoint_max_isoc_bpi() and
usb_submit_urb() as a condition for eUSB2 isoc double bw.
since v1:
https://lore.kernel.org/linux-usb/20250616093730.2569328-2-mathias.nyman@linux.intel.com
- Introduce uvc_endpoint_max_isoc_bpi() to obtain maximum bytes per
interval value for an endpoint, in a new patch (3rd). This code has been
slightly reworked from the instance in the UVC driver, including support
for SuperSpeedPlus Isochronous Endpoint Companion.
- Use usb_endpoint_max_isoc_bpi() in the UVC driver instead of open-coding
eUSB2 support there, also drop now-redundant uvc_endpoint_max_bpi().
- Use u32 for maximum bpi and related information in the UVC driver -- the
value could be larger than a 16-bit type can hold.
- Assume max in usb_submit_urb() is a natural number as
usb_endpoint_maxp() returns only natural numbers (2nd patch).
Link: https://lore.kernel.org/r/20250820143824.551777-1-sakari.ailus@linux.intel.com
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xHC controller may immediately reuse a slot_id after it's disabled,
giving it to a new enumerating device before the xhci driver freed
all resources related to the disabled device.
In such a scenario, device-A with slot_id equal to 1 is disconnecting
while device-B is enumerating, device-B will fail to enumerate in the
follow sequence.
1.[device-A] send disable slot command
2.[device-B] send enable slot command
3.[device-A] disable slot command completed and wakeup waiting thread
4.[device-B] enable slot command completed with slot_id equal to 1 and
wakeup waiting thread
5.[device-B] driver checks that slot_id is still in use (by device-A) in
xhci_alloc_virt_device, and fail to enumerate due to this
conflict
6.[device-A] xhci->devs[slot_id] set to NULL in xhci_free_virt_device
To fix driver's slot_id resources conflict, clear xhci->devs[slot_id] and
xhci->dcbba->dev_context_ptrs[slot_id] pointers in the interrupt context
when disable slot command completes successfully. Simultaneously, adjust
function xhci_free_virt_device to accurately handle device release.
[minor smatch warning and commit message fix -Mathias]
Cc: stable@vger.kernel.org
Fixes: 7faac1953e ("xhci: avoid race between disable slot command and host runtime suspend")
Signed-off-by: Weitao Wang <WeitaoWang-oc@zhaoxin.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250819125844.2042452-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Increase the External ROM access timeouts to prevent failures during
programming of External SPI EEPROM chips. The current timeouts are
too short for some SPI EEPROMs used with uPD720201 controllers.
The current timeout for Chip Erase in renesas_rom_erase() is 100 ms ,
the current timeout for Sector Erase issued by the controller before
Page Program in renesas_fw_download_image() is also 100 ms. Neither
timeout is sufficient for e.g. the Macronix MX25L5121E or MX25V5126F.
MX25L5121E reference manual [1] page 35 section "ERASE AND PROGRAMMING
PERFORMANCE" and page 23 section "Table 8. AC CHARACTERISTICS (Temperature
= 0°C to 70°C for Commercial grade, VCC = 2.7V ~ 3.6V)" row "tCE" indicate
that the maximum time required for Chip Erase opcode to complete is 2 s,
and for Sector Erase it is 300 ms .
MX25V5126F reference manual [2] page 47 section "13. ERASE AND PROGRAMMING
PERFORMANCE (2.3V - 3.6V)" and page 42 section "Table 8. AC CHARACTERISTICS
(Temperature = -40°C to 85°C for Industrial grade, VCC = 2.3V - 3.6V)" row
"tCE" indicate that the maximum time required for Chip Erase opcode to
complete is 3.2 s, and for Sector Erase it is 400 ms .
Update the timeouts such, that Chip Erase timeout is set to 5 seconds,
and Sector Erase timeout is set to 500 ms. Such lengthy timeouts ought
to be sufficient for majority of SPI EEPROM chips.
[1] https://www.macronix.com/Lists/Datasheet/Attachments/8634/MX25L5121E,%203V,%20512Kb,%20v1.3.pdf
[2] https://www.macronix.com/Lists/Datasheet/Attachments/8750/MX25V5126F,%202.5V,%20512Kb,%20v1.1.pdf
Fixes: 2478be82de ("usb: renesas-xhci: Add ROM loader for uPD720201")
Cc: stable <stable@kernel.org>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Link: https://lore.kernel.org/r/20250802225526.25431-1-marek.vasut+renesas@mailbox.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When encounters some errors like these:
xhci_hcd 0000:4a:00.2: xHCI dying or halted, can't queue_command
xhci_hcd 0000:4a:00.2: FIXME: allocate a command ring segment
usb usb5-port6: couldn't allocate usb_device
It's hard to know whether xhc_state is dying or halted. So it's better
to print xhc_state's value which can help locate the resaon of the bug.
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20250725060117.1773770-1-suhui@nfschina.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a subtle contradiction between sections of the xHCI 1.2 spec
regarding the initialization of Input Endpoint Context fields. Section
4.8.2 ("Endpoint Context Initialization") states that all fields should
be initialized to 0. However, Section 6.2.3 ("Endpoint Context", p.453)
specifies that the Average TRB Length (avg_trb_len) field shall be
greater than 0, and explicitly notes (p.454): "Software shall set
Average TRB Length to '8' for control endpoints."
Strictly setting all fields to 0 during initialization conflicts with
the specific recommendation for control endpoints. In practice, setting
avg_trb_len = 0 is not meaningful for the hardware/firmware, as the
value is used for bandwidth calculation.
Motivation: Our company is developing a custom Virtual xHC hardware
platform that strictly follows the xHCI spec and its recommendations.
During validation, we observed that enumeration fails and a parameter
error (TRB Completion Code = 5) is reported if avg_trb_len for EP0 is
not set to 8 as recommended by Section 6.2.3. This demonstrates the
importance of assigning a meaningful, non-zero value to avg_trb_len,
even in virtualized or emulated environments.
This patch explicitly sets avg_trb_len to 8 for EP0 in
xhci_setup_addressable_virt_dev(), as recommended in Section 6.2.3, to
prevent potential issues with xHCI host controllers that enforce the
spec strictly.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=220033
Signed-off-by: Jay Chen <shawn2000100@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250717073107.488599-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <gregkh@linuxfoundation.org>
During the High-Speed Isochronous Audio transfers, xHCI
controller on certain AMD platforms experiences momentary data
loss. This results in Missed Service Errors (MSE) being
generated by the xHCI.
The root cause of the MSE is attributed to the ISOC OUT endpoint
being omitted from scheduling. This can happen when an IN
endpoint with a 64ms service interval either is pre-scheduled
prior to the ISOC OUT endpoint or the interval of the ISOC OUT
endpoint is shorter than that of the IN endpoint. Consequently,
the OUT service is neglected when an IN endpoint with a service
interval exceeding 32ms is scheduled concurrently (every 64ms in
this scenario).
This issue is particularly seen on certain older AMD platforms.
To mitigate this problem, it is recommended to adjust the service
interval of the IN endpoint to not exceed 32ms (interval 8). This
adjustment ensures that the OUT endpoint will not be bypassed,
even if a smaller interval value is utilized.
Cc: stable <stable@kernel.org>
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250627144127.3889714-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 6ccb83d6c4.
Commit 6ccb83d6c4 ("usb: xhci: Implement xhci_handshake_check_state()
helper") was introduced to workaround watchdog timeout issues on some
platforms, allowing xhci_reset() to bail out early without waiting
for the reset to complete.
Skipping the xhci handshake during a reset is a dangerous move. The
xhci specification explicitly states that certain registers cannot
be accessed during reset in section 5.4.1 USB Command Register (USBCMD),
Host Controller Reset (HCRST) field:
"This bit is cleared to '0' by the Host Controller when the reset
process is complete. Software cannot terminate the reset process
early by writinga '0' to this bit and shall not write any xHC
Operational or Runtime registers until while HCRST is '1'."
This behavior causes a regression on SNPS DWC3 USB controller with
dual-role capability. When the DWC3 controller exits host mode and
removes xhci while a reset is still in progress, and then tries to
configure its hardware for device mode, the ongoing reset leads to
register access issues; specifically, all register reads returns 0.
These issues extend beyond the xhci register space (which is expected
during a reset) and affect the entire DWC3 IP block, causing the DWC3
device mode to malfunction.
Cc: stable <stable@kernel.org>
Fixes: 6ccb83d6c4 ("usb: xhci: Implement xhci_handshake_check_state() helper")
Signed-off-by: Roy Luo <royluo@google.com>
Link: https://lore.kernel.org/r/20250522190912.457583-3-royluo@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xhci_reset() currently returns -ENODEV if XHCI_STATE_REMOVING is
set, without completing the xhci handshake, unless the reset completes
exceptionally quickly. This behavior causes a regression on Synopsys
DWC3 USB controllers with dual-role capabilities.
Specifically, when a DWC3 controller exits host mode and removes xhci
while a reset is still in progress, and then attempts to configure its
hardware for device mode, the ongoing, incomplete reset leads to
critical register access issues. All register reads return zero, not
just within the xHCI register space (which might be expected during a
reset), but across the entire DWC3 IP block.
This patch addresses the issue by preventing xhci_reset() from being
called in xhci_resume() and bailing out early in the reinit flow when
XHCI_STATE_REMOVING is set.
Cc: stable <stable@kernel.org>
Fixes: 6ccb83d6c4 ("usb: xhci: Implement xhci_handshake_check_state() helper")
Suggested-by: Mathias Nyman <mathias.nyman@intel.com>
Signed-off-by: Roy Luo <royluo@google.com>
Link: https://lore.kernel.org/r/20250522190912.457583-2-royluo@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the dynamic device name instead of the hardcoded string "at91"
when creating the OHCI host controller driver.
This ensures that the device name is more flexible
and correctly reflects the actual device in the system.
This will be in sync with ehci at91 driver.
Before this patch:
[root@sam9x75eb ~]$ dmesg | grep usb
[ 1.464487] usb usb1: Manufacturer: Linux 6.16.0-rc2 ehci_hcd
[ 1.470210] usb usb1: SerialNumber: 700000.usb-ehci
[ 1.595683] usb usb2: Manufacturer: Linux 6.16.0-rc2 ohci_hcd
[ 1.601406] usb usb2: SerialNumber: at91
After this patch:
[root@sam9x75eb ~]$ dmesg | grep usb
[ 1.464487] usb usb1: Manufacturer: Linux 6.16.0-rc2 ehci_hcd
[ 1.470210] usb usb1: SerialNumber: 700000.usb-ehci
[ 1.595683] usb usb2: Manufacturer: Linux 6.16.0-rc2 ohci_hcd
[ 1.601406] usb usb2: SerialNumber: 600000.usb-ohci
Signed-off-by: Mihai Sain <mihai.sain@microchip.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20250616061759.3384-2-mihai.sain@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix kernel-doc warning by documenting the @desc parameter:
drivers/usb/host/xhci.c:1369: warning: Function parameter or struct member 'desc' not described in 'xhci_get_endpoint_index'
Add detailed description of the @desc parameter and clarify the indexing
logic for control endpoints vs other types. This brings the documentation
in line with kernel-doc requirements while maintaining technical accuracy.
Signed-off-by: Hans Zhang <18255117159@163.com>
Link: https://lore.kernel.org/r/20250506033101.206180-1-18255117159@163.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
