[PATCH 6.18 064/309] usb: core: new quirk to handle devices with zero configurations

Greg Kroah-Hartman
2026-03-31T17:00:48Z

From: Jie Deng <dengjie03@kylinos.cn>

[ Upstream commit 9f6a983cfa22ac662c86e60816d3a357d4b551e9 ]

Some USB devices incorrectly report bNumConfigurations as 0 in their
device descriptor, which causes the USB core to reject them during
enumeration.
logs:
usb 1-2: device descriptor read/64, error -71
usb 1-2: no configurations
usb 1-2: can't read configurations, error -22

However, these devices actually work correctly when
treated as having a single configuration.

Add a new quirk USB_QUIRK_FORCE_ONE_CONFIG to handle such devices.
When this quirk is set, assume the device has 1 configuration instead
of failing with -EINVAL.

This quirk is applied to the device with VID:PID 5131:2007 which
exhibits this behavior.

Signed-off-by: Jie Deng <dengjie03@kylinos.cn>
Link: https://patch.msgid.link/20260227084931.1527461-1-dengjie03@kylinos.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
Documentation/admin-guide/kernel-parameters.txt | 3 +++
drivers/usb/core/config.c | 6 +++++-
drivers/usb/core/quirks.c | 5 +++++
include/linux/usb/quirks.h | 3 +++
4 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6c42061ca20e5..ab4e03f91e744 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -7925,6 +7925,9 @@
p = USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT
(Reduce timeout of the SET_ADDRESS
request from 5000 ms to 500 ms);
+ q = USB_QUIRK_FORCE_ONE_CONFIG (Device
+ claims zero configurations,
+ forcing to 1);
Example: quirks=0781:5580:bk,0a5c:5834:gij

usbhid.mousepoll=
diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 2bb1ceb9d621a..3067e18ec4d8a 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -927,7 +927,11 @@ int usb_get_configuration(struct usb_device *dev)
dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
}

- if (ncfg < 1) {
+ if (ncfg < 1 && dev->quirks & USB_QUIRK_FORCE_ONE_CONFIG) {
+ dev_info(ddev, "Device claims zero configurations, forcing to 1\n");
+ dev->descriptor.bNumConfigurations = 1;
+ ncfg = 1;
+ } else if (ncfg < 1) {
dev_err(ddev, "no configurations\n");
return -EINVAL;
}
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 9fef2f4d604a5..65168eb89295c 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -141,6 +141,8 @@ static int quirks_param_set(const char *value, const struct kernel_param *kp)
case 'p':
flags |= USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT;
break;
+ case 'q':
+ flags |= USB_QUIRK_FORCE_ONE_CONFIG;
/* Ignore unrecognized flag characters */
}
}
@@ -597,6 +599,9 @@ static const struct usb_device_id usb_quirk_list[] = {
/* VCOM device */
{ USB_DEVICE(0x4296, 0x7570), .driver_info = USB_QUIRK_CONFIG_INTF_STRINGS },

+ /* Noji-MCS SmartCard Reader */
+ { USB_DEVICE(0x5131, 0x2007), .driver_info = USB_QUIRK_FORCE_ONE_CONFIG },
+
/* INTEL VALUE SSD */
{ USB_DEVICE(0x8086, 0xf1a5), .driver_info = USB_QUIRK_RESET_RESUME },

diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 2f7bd2fdc6164..b3cc7beab4a3c 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -78,4 +78,7 @@
/* skip BOS descriptor request */
#define USB_QUIRK_NO_BOS BIT(17)

+/* Device claims zero configurations, forcing to 1 */
+#define USB_QUIRK_FORCE_ONE_CONFIG BIT(18)
+
#endif /* __LINUX_USB_QUIRKS_H */
--
2.51.0