On 10/4/2024 6:33 AM, Greg KH wrote: > On Fri, Sep 13, 2024 at 05:39:21PM +0200, Peter Korsgaard wrote: >> On 9/11/24 03:32, Vodicka, Michal wrote: >>>> Hmm, very odd. How are you testing this on the host side? >>> >>> We just attach the device and check the registry values created by OS >>> for our device. As >>> HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USB\VID_XXXX&PID_YYYY&MI_NN\<device_instance>\Device Parameters. >>> When it works our extended properties are created there. >>> >>> We check the communication using USB analyzer which clearly shows >>> wValue bytes are in opposite order than documented. This is SETUP >>> packet captured: >>> >>> Offset 0 1 2 3 4 5 6 7 >>> 0x000 C1 A1 02 00 05 00 0A 00 >>> >>> As you can see, this is interface request and out interface number was >>> 2 which is in the low byte of wValue. >> >> OK, annoying. I am traveling for conferences this/next week so I cannot >> verify here, but presumably you are correct. Do you perhaps have a more >> complete capture you can share? >> >> >>> >>>> Could it be that you are running into the WinUSB bug described here: >>> >>> No. The mentioned bug is in wIndex and out problem is wValue. Also, >>> MSOS descriptors are read before WinUsb is even run. >> >> Ahh yes, indeed. >> >> >>> What Windows version were you using and have you used USB analyzer to >>> check the communication? >> >> It's been a while, but I believe Windows 10. In the end I ended up shuffling >> the interfaces around so the one with the MSOS descriptors was interface 0 >> for better compatibility, so it is possible that something went wrong with >> my interface != 0 tests. >> >> If so, then I am fine with reverting, but we should probably add a comment >> explaining that the documentation is wrong. > > Ok, Michal, can you add some text tothe changelog and send a v2 for > this? > HI Michal I am facing a similar issue where the Windows host is unable to fetch OS descriptor from the device running v6.9 kernel with Android mainline. Tested your patch and it fixes the issue. Host Machine: Windows10 22H2 Composite device: NCM+Android Debugger (ADB) Issue: Windows host is unable to fetch the OS descriptor for ADB interface and hence ADB functionality is failing. Also checked the USB analyzer output and it shows wValue bytes in opposite order than documented i.e interface number is in the lower bytes (for Extended Properties OS Desc) Thanks Elson
