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authorLinus Torvalds <torvalds@linux-foundation.org>2021-07-05 14:16:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-07-05 14:16:22 -0700
commit79160a603bdb51916226caf4a6616cc4e1c58a58 (patch)
tree6aa2dd8ce76799921ba56eace1c0262ab947f115 /Documentation
parentc932ed0adb09a7fa6d6649ee04dd78c83ab07ada (diff)
parent7756f1d6369e61d1cc47d6e51619d1e1d1681a2e (diff)
Merge tag 'usb-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB / Thunderbolt updates from Greg KH: "Here is the big set of USB and Thunderbolt patches for 5.14-rc1. Nothing major here just lots of little changes for new hardware and features. Highlights are: - more USB 4 support added to the thunderbolt core - build warning fixes all over the place - usb-serial driver updates and new device support - mtu3 driver updates - gadget driver updates - dwc3 driver updates - dwc2 driver updates - isp1760 host driver updates - musb driver updates - lots of other tiny things. Full details are in the shortlog. All of these have been in linux-next for a while now with no reported issues" * tag 'usb-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (223 commits) phy: qcom-qusb2: Add configuration for SM4250 and SM6115 dt-bindings: phy: qcom,qusb2: document sm4250/6115 compatible dt-bindings: usb: qcom,dwc3: Add bindings for sm6115/4250 USB: cdc-acm: blacklist Heimann USB Appset device usb: xhci-mtk: allow multiple Start-Split in a microframe usb: ftdi-elan: remove redundant continue statement in a while-loop usb: class: cdc-wdm: return the correct errno code xhci: remove redundant continue statement usb: dwc3: Fix debugfs creation flow usb: gadget: hid: fix error return code in hid_bind() usb: gadget: eem: fix echo command packet response issue usb: gadget: f_hid: fix endianness issue with descriptors Revert "USB: misc: Add onboard_usb_hub driver" Revert "of/platform: Add stubs for of_platform_device_create/destroy()" Revert "usb: host: xhci-plat: Create platform device for onboard hubs in probe()" Revert "arm64: dts: qcom: sc7180-trogdor: Add nodes for onboard USB hub" xhci: solve a double free problem while doing s4 xhci: handle failed buffer copy to URB sg list and fix a W=1 copiler warning xhci: Add adaptive interrupt rate for isoch TRBs with XHCI_AVOID_BEI quirk xhci: Remove unused defines for ERST_SIZE and ERST_ENTRIES ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/configfs-usb-gadget-uac22
-rw-r--r--Documentation/ABI/testing/sysfs-bus-thunderbolt82
-rw-r--r--Documentation/ABI/testing/sysfs-bus-usb11
-rw-r--r--Documentation/ABI/testing/sysfs-devices-removable18
-rw-r--r--Documentation/admin-guide/thunderbolt.rst29
-rw-r--r--Documentation/devicetree/bindings/phy/allwinner,sun8i-h3-usb-phy.yaml4
-rw-r--r--Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml2
-rw-r--r--Documentation/devicetree/bindings/usb/allwinner,sun4i-a10-musb.yaml3
-rw-r--r--Documentation/devicetree/bindings/usb/cdns,usb3.yaml1
-rw-r--r--Documentation/devicetree/bindings/usb/dwc2.yaml1
-rw-r--r--Documentation/devicetree/bindings/usb/nxp,isp1760.yaml69
-rw-r--r--Documentation/devicetree/bindings/usb/qcom,dwc3.yaml2
-rw-r--r--Documentation/devicetree/bindings/usb/realtek,rts5411.yaml62
-rw-r--r--Documentation/driver-api/usb/error-codes.rst3
-rw-r--r--Documentation/usb/gadget-testing.rst2
15 files changed, 256 insertions, 35 deletions
diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac2 b/Documentation/ABI/testing/configfs-usb-gadget-uac2
index d4356c8b8cd6..26fb8e9b4e61 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uac2
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uac2
@@ -8,6 +8,8 @@ Description:
c_chmask capture channel mask
c_srate capture sampling rate
c_ssize capture sample size (bytes)
+ c_sync capture synchronization type (async/adaptive)
+ fb_max maximum extra bandwidth in async mode
p_chmask playback channel mask
p_srate playback sampling rate
p_ssize playback sample size (bytes)
diff --git a/Documentation/ABI/testing/sysfs-bus-thunderbolt b/Documentation/ABI/testing/sysfs-bus-thunderbolt
index c41c68f64693..95c21d6c9a84 100644
--- a/Documentation/ABI/testing/sysfs-bus-thunderbolt
+++ b/Documentation/ABI/testing/sysfs-bus-thunderbolt
@@ -1,4 +1,4 @@
-What: /sys/bus/thunderbolt/devices/.../domainX/boot_acl
+What: /sys/bus/thunderbolt/devices/.../domainX/boot_acl
Date: Jun 2018
KernelVersion: 4.17
Contact: thunderbolt-software@lists.01.org
@@ -21,7 +21,7 @@ Description: Holds a comma separated list of device unique_ids that
If a device is authorized automatically during boot its
boot attribute is set to 1.
-What: /sys/bus/thunderbolt/devices/.../domainX/deauthorization
+What: /sys/bus/thunderbolt/devices/.../domainX/deauthorization
Date: May 2021
KernelVersion: 5.12
Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
@@ -30,7 +30,7 @@ Description: This attribute tells whether the system supports
de-authorize PCIe tunnel by writing 0 to authorized
attribute under each device.
-What: /sys/bus/thunderbolt/devices/.../domainX/iommu_dma_protection
+What: /sys/bus/thunderbolt/devices/.../domainX/iommu_dma_protection
Date: Mar 2019
KernelVersion: 4.21
Contact: thunderbolt-software@lists.01.org
@@ -39,7 +39,7 @@ Description: This attribute tells whether the system uses IOMMU
it is not (DMA protection is solely based on Thunderbolt
security levels).
-What: /sys/bus/thunderbolt/devices/.../domainX/security
+What: /sys/bus/thunderbolt/devices/.../domainX/security
Date: Sep 2017
KernelVersion: 4.13
Contact: thunderbolt-software@lists.01.org
@@ -61,7 +61,7 @@ Description: This attribute holds current Thunderbolt security level
the BIOS.
======= ==================================================
-What: /sys/bus/thunderbolt/devices/.../authorized
+What: /sys/bus/thunderbolt/devices/.../authorized
Date: Sep 2017
KernelVersion: 4.13
Contact: thunderbolt-software@lists.01.org
@@ -95,14 +95,14 @@ Description: This attribute is used to authorize Thunderbolt devices
EKEYREJECTED if the challenge response did not match.
== ========================================================
-What: /sys/bus/thunderbolt/devices/.../boot
+What: /sys/bus/thunderbolt/devices/.../boot
Date: Jun 2018
KernelVersion: 4.17
Contact: thunderbolt-software@lists.01.org
Description: This attribute contains 1 if Thunderbolt device was already
authorized on boot and 0 otherwise.
-What: /sys/bus/thunderbolt/devices/.../generation
+What: /sys/bus/thunderbolt/devices/.../generation
Date: Jan 2020
KernelVersion: 5.5
Contact: Christian Kellner <christian@kellner.me>
@@ -110,7 +110,7 @@ Description: This attribute contains the generation of the Thunderbolt
controller associated with the device. It will contain 4
for USB4.
-What: /sys/bus/thunderbolt/devices/.../key
+What: /sys/bus/thunderbolt/devices/.../key
Date: Sep 2017
KernelVersion: 4.13
Contact: thunderbolt-software@lists.01.org
@@ -213,12 +213,15 @@ Description: When new NVM image is written to the non-active NVM
restarted with the new NVM firmware. If the image
verification fails an error code is returned instead.
- This file will accept writing values "1" or "2"
+ This file will accept writing values "1", "2" or "3".
- Writing "1" will flush the image to the storage
area and authenticate the image in one action.
- Writing "2" will run some basic validation on the image
and flush it to the storage area.
+ - Writing "3" will authenticate the image that is
+ currently written in the storage area. This is only
+ supported with USB4 devices and retimers.
When read holds status of the last authentication
operation if an error occurred during the process. This
@@ -226,6 +229,20 @@ Description: When new NVM image is written to the non-active NVM
based mailbox before the device is power cycled. Writing
0 here clears the status.
+What: /sys/bus/thunderbolt/devices/.../nvm_authenticate_on_disconnect
+Date: Oct 2020
+KernelVersion: v5.9
+Contact: Mario Limonciello <mario.limonciello@dell.com>
+Description: For supported devices, automatically authenticate the new Thunderbolt
+ image when the device is disconnected from the host system.
+
+ This file will accept writing values "1" or "2"
+
+ - Writing "1" will flush the image to the storage
+ area and prepare the device for authentication on disconnect.
+ - Writing "2" will run some basic validation on the image
+ and flush it to the storage area.
+
What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/key
Date: Jan 2018
KernelVersion: 4.15
@@ -276,6 +293,39 @@ Contact: thunderbolt-software@lists.01.org
Description: This contains XDomain service specific settings as
bitmask. Format: %x
+What: /sys/bus/thunderbolt/devices/usb4_portX/link
+Date: Sep 2021
+KernelVersion: v5.14
+Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
+Description: Returns the current link mode. Possible values are
+ "usb4", "tbt" and "none".
+
+What: /sys/bus/thunderbolt/devices/usb4_portX/offline
+Date: Sep 2021
+KernelVersion: v5.14
+Contact: Rajmohan Mani <rajmohan.mani@intel.com>
+Description: Writing 1 to this attribute puts the USB4 port into
+ offline mode. Only allowed when there is nothing
+ connected to the port (link attribute returns "none").
+ Once the port is in offline mode it does not receive any
+ hotplug events. This is used to update NVM firmware of
+ on-board retimers. Writing 0 puts the port back to
+ online mode.
+
+ This attribute is only visible if the platform supports
+ powering on retimers when there is no cable connected.
+
+What: /sys/bus/thunderbolt/devices/usb4_portX/rescan
+Date: Sep 2021
+KernelVersion: v5.14
+Contact: Rajmohan Mani <rajmohan.mani@intel.com>
+Description: When the USB4 port is in offline mode writing 1 to this
+ attribute forces rescan of the sideband for on-board
+ retimers. Each retimer appear under the USB4 port as if
+ the USB4 link was up. These retimers act in the same way
+ as if the cable was connected so upgrading their NVM
+ firmware can be done the usual way.
+
What: /sys/bus/thunderbolt/devices/<device>:<port>.<index>/device
Date: Oct 2020
KernelVersion: v5.9
@@ -308,17 +358,3 @@ Date: Oct 2020
KernelVersion: v5.9
Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
Description: Retimer vendor identifier read from the hardware.
-
-What: /sys/bus/thunderbolt/devices/.../nvm_authenticate_on_disconnect
-Date: Oct 2020
-KernelVersion: v5.9
-Contact: Mario Limonciello <mario.limonciello@dell.com>
-Description: For supported devices, automatically authenticate the new Thunderbolt
- image when the device is disconnected from the host system.
-
- This file will accept writing values "1" or "2"
-
- - Writing "1" will flush the image to the storage
- area and prepare the device for authentication on disconnect.
- - Writing "2" will run some basic validation on the image
- and flush it to the storage area.
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index bf2c1968525f..73eb23bc1f34 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -154,17 +154,6 @@ Description:
files hold a string value (enable or disable) indicating whether
or not USB3 hardware LPM U1 or U2 is enabled for the device.
-What: /sys/bus/usb/devices/.../removable
-Date: February 2012
-Contact: Matthew Garrett <mjg@redhat.com>
-Description:
- Some information about whether a given USB device is
- physically fixed to the platform can be inferred from a
- combination of hub descriptor bits and platform-specific data
- such as ACPI. This file will read either "removable" or
- "fixed" if the information is available, and "unknown"
- otherwise.
-
What: /sys/bus/usb/devices/.../ltm_capable
Date: July 2012
Contact: Sarah Sharp <sarah.a.sharp@linux.intel.com>
diff --git a/Documentation/ABI/testing/sysfs-devices-removable b/Documentation/ABI/testing/sysfs-devices-removable
new file mode 100644
index 000000000000..bda6c320c8d3
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-removable
@@ -0,0 +1,18 @@
+What: /sys/devices/.../removable
+Date: May 2021
+Contact: Rajat Jain <rajatxjain@gmail.com>
+Description:
+ Information about whether a given device can be removed from the
+ platform by the user. This is determined by its subsystem in a
+ bus / platform-specific way. This attribute is only present for
+ devices that can support determining such information:
+
+ "removable": device can be removed from the platform by the user
+ "fixed": device is fixed to the platform / cannot be removed
+ by the user.
+ "unknown": The information is unavailable / cannot be deduced.
+
+ Currently this is only supported by USB (which infers the
+ information from a combination of hub descriptor bits and
+ platform-specific data such as ACPI) and PCI (which gets this
+ from ACPI / device tree).
diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst
index f18e881373c4..2ed79f41a411 100644
--- a/Documentation/admin-guide/thunderbolt.rst
+++ b/Documentation/admin-guide/thunderbolt.rst
@@ -256,6 +256,35 @@ Note names of the NVMem devices ``nvm_activeN`` and ``nvm_non_activeN``
depend on the order they are registered in the NVMem subsystem. N in
the name is the identifier added by the NVMem subsystem.
+Upgrading on-board retimer NVM when there is no cable connected
+---------------------------------------------------------------
+If the platform supports, it may be possible to upgrade the retimer NVM
+firmware even when there is nothing connected to the USB4
+ports. When this is the case the ``usb4_portX`` devices have two special
+attributes: ``offline`` and ``rescan``. The way to upgrade the firmware
+is to first put the USB4 port into offline mode::
+
+ # echo 1 > /sys/bus/thunderbolt/devices/0-0/usb4_port1/offline
+
+This step makes sure the port does not respond to any hotplug events,
+and also ensures the retimers are powered on. The next step is to scan
+for the retimers::
+
+ # echo 1 > /sys/bus/thunderbolt/devices/0-0/usb4_port1/rescan
+
+This enumerates and adds the on-board retimers. Now retimer NVM can be
+upgraded in the same way than with cable connected (see previous
+section). However, the retimer is not disconnected as we are offline
+mode) so after writing ``1`` to ``nvm_authenticate`` one should wait for
+5 or more seconds before running rescan again::
+
+ # echo 1 > /sys/bus/thunderbolt/devices/0-0/usb4_port1/rescan
+
+This point if everything went fine, the port can be put back to
+functional state again::
+
+ # echo 0 > /sys/bus/thunderbolt/devices/0-0/usb4_port1/offline
+
Upgrading NVM when host controller is in safe mode
--------------------------------------------------
If the existing NVM is not properly authenticated (or is missing) the
diff --git a/Documentation/devicetree/bindings/phy/allwinner,sun8i-h3-usb-phy.yaml b/Documentation/devicetree/bindings/phy/allwinner,sun8i-h3-usb-phy.yaml
index f80431060803..e288450e0844 100644
--- a/Documentation/devicetree/bindings/phy/allwinner,sun8i-h3-usb-phy.yaml
+++ b/Documentation/devicetree/bindings/phy/allwinner,sun8i-h3-usb-phy.yaml
@@ -15,7 +15,9 @@ properties:
const: 1
compatible:
- const: allwinner,sun8i-h3-usb-phy
+ enum:
+ - allwinner,sun8i-h3-usb-phy
+ - allwinner,sun50i-h616-usb-phy
reg:
items:
diff --git a/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
index 930da598c969..ec9ccaaba098 100644
--- a/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
+++ b/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
@@ -23,6 +23,8 @@ properties:
- qcom,msm8998-qusb2-phy
- qcom,sdm660-qusb2-phy
- qcom,ipq6018-qusb2-phy
+ - qcom,sm4250-qusb2-phy
+ - qcom,sm6115-qusb2-phy
- items:
- enum:
- qcom,sc7180-qusb2-phy
diff --git a/Documentation/devicetree/bindings/usb/allwinner,sun4i-a10-musb.yaml b/Documentation/devicetree/bindings/usb/allwinner,sun4i-a10-musb.yaml
index 0f520f17735e..933fa356d2ce 100644
--- a/Documentation/devicetree/bindings/usb/allwinner,sun4i-a10-musb.yaml
+++ b/Documentation/devicetree/bindings/usb/allwinner,sun4i-a10-musb.yaml
@@ -22,6 +22,9 @@ properties:
- allwinner,sun8i-a83t-musb
- allwinner,sun50i-h6-musb
- const: allwinner,sun8i-a33-musb
+ - items:
+ - const: allwinner,sun50i-h616-musb
+ - const: allwinner,sun8i-h3-musb
reg:
maxItems: 1
diff --git a/Documentation/devicetree/bindings/usb/cdns,usb3.yaml b/Documentation/devicetree/bindings/usb/cdns,usb3.yaml
index 8dedfa16c992..dc9d6ed0781d 100644
--- a/Documentation/devicetree/bindings/usb/cdns,usb3.yaml
+++ b/Documentation/devicetree/bindings/usb/cdns,usb3.yaml
@@ -75,6 +75,7 @@ required:
- reg
- reg-names
- interrupts
+ - interrupt-names
additionalProperties: false
diff --git a/Documentation/devicetree/bindings/usb/dwc2.yaml b/Documentation/devicetree/bindings/usb/dwc2.yaml
index e5ee51b7b470..10c7d9b6cc53 100644
--- a/Documentation/devicetree/bindings/usb/dwc2.yaml
+++ b/Documentation/devicetree/bindings/usb/dwc2.yaml
@@ -24,6 +24,7 @@ properties:
- rockchip,rk3188-usb
- rockchip,rk3228-usb
- rockchip,rk3288-usb
+ - rockchip,rk3308-usb
- rockchip,rk3328-usb
- rockchip,rk3368-usb
- rockchip,rv1108-usb
diff --git a/Documentation/devicetree/bindings/usb/nxp,isp1760.yaml b/Documentation/devicetree/bindings/usb/nxp,isp1760.yaml
new file mode 100644
index 000000000000..a88f99adfe8e
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/nxp,isp1760.yaml
@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/nxp,isp1760.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP ISP1760 family controller bindings
+
+maintainers:
+ - Sebastian Siewior <bigeasy@linutronix.de>
+ - Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+
+description: |
+ NXP ISP1760 family, which includes ISP1760/1761/1763 devicetree controller
+ bindings
+
+properties:
+ compatible:
+ enum:
+ - nxp,usb-isp1760
+ - nxp,usb-isp1761
+ - nxp,usb-isp1763
+ reg:
+ maxItems: 1
+
+ interrupts:
+ minItems: 1
+ maxItems: 2
+ items:
+ - description: Host controller interrupt
+ - description: Device controller interrupt in isp1761
+
+ interrupt-names:
+ minItems: 1
+ maxItems: 2
+ items:
+ - const: host
+ - const: peripheral
+
+ bus-width:
+ description:
+ Number of data lines.
+ enum: [8, 16, 32]
+ default: 32
+
+ dr_mode:
+ enum:
+ - host
+ - peripheral
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ usb@40200000 {
+ compatible = "nxp,usb-isp1763";
+ reg = <0x40200000 0x100000>;
+ interrupts = <GIC_SPI 114 IRQ_TYPE_LEVEL_HIGH>;
+ bus-width = <16>;
+ dr_mode = "host";
+ };
+
+...
diff --git a/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml b/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml
index 413299b5fe2b..4e6451789806 100644
--- a/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml
@@ -19,6 +19,8 @@ properties:
- qcom,sc7280-dwc3
- qcom,sdm845-dwc3
- qcom,sdx55-dwc3
+ - qcom,sm4250-dwc3
+ - qcom,sm6115-dwc3
- qcom,sm8150-dwc3
- qcom,sm8250-dwc3
- qcom,sm8350-dwc3
diff --git a/Documentation/devicetree/bindings/usb/realtek,rts5411.yaml b/Documentation/devicetree/bindings/usb/realtek,rts5411.yaml
new file mode 100644
index 000000000000..04ee255eb4f0
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/realtek,rts5411.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/realtek,rts5411.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Binding for the Realtek RTS5411 USB 3.0 hub controller
+
+maintainers:
+ - Matthias Kaehlcke <mka@chromium.org>
+
+allOf:
+ - $ref: usb-device.yaml#
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - usbbda,5411
+ - usbbda,411
+
+ reg: true
+
+ vdd-supply:
+ description:
+ phandle to the regulator that provides power to the hub.
+
+ companion-hub:
+ $ref: '/schemas/types.yaml#/definitions/phandle'
+ description:
+ phandle to the companion hub on the controller.
+
+required:
+ - companion-hub
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ usb {
+ dr_mode = "host";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ /* 2.0 hub on port 1 */
+ hub_2_0: hub@1 {
+ compatible = "usbbda,5411";
+ reg = <1>;
+ vdd-supply = <&pp3300_hub>;
+ companion-hub = <&hub_3_0>;
+ };
+
+ /* 3.0 hub on port 2 */
+ hub_3_0: hub@2 {
+ compatible = "usbbda,411";
+ reg = <2>;
+ vdd-supply = <&pp3300_hub>;
+ companion-hub = <&hub_2_0>;
+ };
+ };
diff --git a/Documentation/driver-api/usb/error-codes.rst b/Documentation/driver-api/usb/error-codes.rst
index a3e84bfac776..8f9790c2d6f8 100644
--- a/Documentation/driver-api/usb/error-codes.rst
+++ b/Documentation/driver-api/usb/error-codes.rst
@@ -61,6 +61,9 @@ USB-specific:
(c) requested data transfer length is invalid: negative
or too large for the host controller.
+``-EBADR`` The wLength value in a control URB's setup packet does
+ not match the URB's transfer_buffer_length.
+
``-ENOSPC`` This request would overcommit the usb bandwidth reserved
for periodic transfers (interrupt, isochronous).
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst
index 2085e7b24eeb..9d6276f82774 100644
--- a/Documentation/usb/gadget-testing.rst
+++ b/Documentation/usb/gadget-testing.rst
@@ -728,6 +728,8 @@ The uac2 function provides these attributes in its function directory:
c_chmask capture channel mask
c_srate capture sampling rate
c_ssize capture sample size (bytes)
+ c_sync capture synchronization type (async/adaptive)
+ fb_max maximum extra bandwidth in async mode
p_chmask playback channel mask
p_srate playback sampling rate
p_ssize playback sample size (bytes)