#214 signal 'process-error' emitted with data: scan_pages Invalid argument

[Alistair]

Scanning periodically fails with an "invalid argument" error.

I haven't been able to see any pattern to this, sometimes it happens after 3 pages are scanned, sometimes after 15.

The relevant part of the log file is:

INFO - gscan2pdf: scanning image of size 4960x7015 pixels at 8 bits/pixel
INFO - gscan2pdf: acquiring gray frame
INFO - gscan2pdf: min/max graylevel value = 255/0
INFO - gscan2pdf: sane_read: Invalid argument
INFO - Scanned page /tmp/gscan2pdf-_JQi/4_54M21MZt.pnm. (scanner status = 4)
INFO - signal 'process-error' emitted with data: scan_pages Invalid argument

I've attached the full log file to the ticket. Note that the above extract starts at line 39124 - I didn't want to lose the work, so rotated, unpapered, OCR'd and saved the pages before quitting.

Version info:

uname -a
Linux archgnome 4.3.3-2-ARCH #1 SMP PREEMPT Wed Dec 23 20:09:18 CET 2015 x86_64 GNU/Linux

gscan2pdf --version
gscan2pdf 1.3.6

scanimage -L
device v4l:/dev/video0' is a Noname Laptop_Integrated_Webcam_HD virtual device deviceepkowa:interpreter:004:007' is a Epson Perfection V370 Photo flatbed scanner

(I'm obviously using the V370, not the Webcam :-))

Thanks,
Alistair

[Alistair]

This appears to be related to the USB handling.

[127838.413688] usb 4-1.2: USB disconnect, device number 10
[127873.712096] usb 4-1.2: new high-speed USB device number 11 using ehci-pci
[127993.213543] usb 4-1.2: USB disconnect, device number 11
[128008.519395] usb 4-1.2: new high-speed USB device number 12 using ehci-pci
[128736.713812] usb 4-1.2: USB disconnect, device number 12
[129301.899668] usb 2-2: new high-speed USB device number 3 using xhci_hcd
[129302.025716] usb 2-2: ep 0x81 - rounding interval to 128 microframes, ep desc says 255 microframes
[129302.025734] usb 2-2: ep 0x2 - rounding interval to 128 microframes, ep desc says 255 microframes
[129320.190914] usb 2-2: ep 0x81 - rounding interval to 128 microframes, ep desc says 255 microframes
[129320.190921] usb 2-2: ep 0x2 - rounding interval to 128 microframes, ep desc says 255 microframes

The dmesg extract above shows the scanner being connected to the PC three times. The first two don't set the rounding interval, while the third connection does. The first two connections experienced the "invalid argumnt" error fairly quickly, while the third connection was able to scan 20 or 30 pages without error.

So this appears to be more of a USB driver issue than a gscan2pdf issue.

Jeffrey, if you don't mind leaving this ticket open for the rest of the week, I'll do some more testing, and it can probably be closed then.

Thanks,
Alistair

[Jeffrey Ratcliffe]

Do you have both USB2 and USB3 ports? If so, try switching to the USB2 port, as USB3 has been causing problems for many backends.

[Alistair]

Hi Jeffrey,

Thanks for your reply.

I do have both USB2 and USB3 ports, and I've had problems with media devices and USB3 previously as well. But...

The weird thing this time is that the problems are appearing on the USB2 ports, it's the USB3 port that is working properly (in the dmesg log above the first two (failing) attempts are ehci-pci, the third (working) one is xhci_hcd).

Thanks again,
Alistair

[Alistair]

This can be closed. It looks like a kernel issue, nothing to do with gscan2pdf.

Thanks!
Alistair