Re: [PATCH] USB: serial: simple: narrow OWON match to avoid breaking VDS1022

[Amit <lestoppe@gmail.com>]

Hi Huang,

	I've updated on the Bugzilla. Let me reply on the queries here
as well.

1. The userspace tool uses libusb and the automatic driver load
prevents it from accessing the device. The software used is:

	 https://github.com/florentbr/Owon-VDS1022

3. The VDS1022 supports some SCPI commands once I enabled it via the
console in the application above. I do not know if it's the same set as
the HDS200 series. 

	However, I want to emphasize that the SCPI interface is a
secondary feature for additional functionality. The userspace tool
above is the more basic / essential function to view the waveforms. 

	The HDS200 is a handheld scope with a built-in waveform display.
The VDS1022 is USB device that depends entirely on the PC software to
view anything at all. Turning it into a generic serial interface is a
downgrade.

2. output of lsusb -v -d 5345:1234

--------------------------------------------------------------------
Bus 001 Device 003: ID 5345:1234 Owon PDS6062T Oscilloscope
Negotiated speed: Full Speed (12Mbps)
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            2 Communications
  bDeviceSubClass         0 [unknown]
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x5345 Owon
  idProduct          0x1234 PDS6062T Oscilloscope
  bcdDevice           10.01
  iManufacturer           1 S
  iProduct                2 U
  iSerial                 3 0
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0029
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower               50mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         5 Physical Interface Device
      bInterfaceSubClass      6 [unknown]
      bInterfaceProtocol     80 
      iInterface              0 
      ** UNRECOGNIZED:  09 21 00 01 00 01 22 00 00
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x03  EP 3 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               0
cannot read device status, Resource temporarily unavailable (11)

--------------------------------------------------------------------

On Mon, 17 Aug 2026 17:35:49 +0800
Huang Wei <huangwei@kylinos.cn> wrote:

> Hi Johan,
> 
> Thanks for the review.
> 
> You're right that the owon 'simple' driver is effectively an alias for
> the generic usbserial driver, so a VDS1022 used through a kernel tty
> would not have been broken by the new match. The reporter's breakage
> is therefore most likely due to a libusb-based userspace tool, which
> can no longer claim the interface once the kernel driver binds to it -
> before commit 4cc01410e1c1 nothing claimed these interfaces in-kernel,
> so such tools worked out of the box.
> 
> leStoppe, to figure out the right fix, could you share:
> 
>  1. which userspace software you use with the VDS1022 (is it a
>     libusb-based tool?);
>  2. the output of "lsusb -v" (or "usb-devices") for the VDS1022;
>  3. whether the VDS1022 supports the same SCPI command set as the
>     HDS200 series.
> 
> Craig, was the intent of 4cc01410e1c1 to cover only the HDS200 series,
> or the whole range of OWON scopes sharing this VID:PID?
> 
> I'll follow up with a v2 that switches to
> USB_DEVICE_INTERFACE_CLASS(), fixes the comment style, and drops the
> wording about falling back to a generic driver.
> 
> Best regards,
> Huang Wei