Recent changes to 66: write timeouts after some time - driver stops working

#66 write timeouts after some time - driver stops working

Paul Grimes — Fri, 29 Mar 2019 13:05:58 -0000

I'm getting ready to post a question on the mailing list about similar looking errors with an NI USB HS on the Raspberry Pi 3 (USB timeout and subsequent USB errors). I'm just trying one last test before I do.

One thing I'd mention immediately is that the Pi's single USB bus is used for communication with the Pi's built-in fast ethernet, so it's possible that network adapter can overload the USB bus alone, without any devices other than the GPIB adapter connected to the Pi's USB port. Internally the Pi acts as a USB OTG device, and maybe that could have some effect?

Another thing is that it can be picky about powering USB devices. Use a powered USB hub with a decent current sourcing capability if you can.

#66 write timeouts after some time - driver stops working

Jan Hilsdorf — Sat, 02 Feb 2019 23:41:41 -0000

So far it never happened on a x86-Platform. And it only happens earlier with high bandwidth. But it also stops working with only the GPIB adapter connected.

#66 write timeouts after some time - driver stops working

Philip Pemberton — Tue, 23 Oct 2018 09:38:15 -0000

Does this happen on e.g. a desktop PC too?

From memory the RPi uses a Synopsys USB host controller IP core in its SoC. I've seen issues with this core and high-bandwidth USB devices on other platforms.

write timeouts after some time - driver stops working

Jan Hilsdorf — Fri, 20 Jul 2018 22:21:32 -0000

After some time the kernel driver stops working. In normal Operation it takes hours, but with heavy USB load (a DVB-S2 adapter) it stops after a few seconds. Until then everything is fine and GPIB communication is possible.

Hardware: ARM, Raspberry Pi 3, Agilent 82357A (chinese clone)

linux-gpib: trunk, r1755

Kernel: 4.14.56-1, Arch Linux Arm

Kernel log:
[ 261.518238] agilent_82357a_generic_write: write aborted ibs 1, tmo 1000
[ 262.558242] agilent_82357a_generic_write: write aborted ibs 1, tmo 1000
[ 263.598841] agilent_82357a_generic_write: write aborted ibs 1, tmo 1000
[ 264.638240] agilent_82357a_generic_write: write aborted ibs 1, tmo 1000
[ 265.678788] agilent_82357a_generic_write: write aborted ibs 1, tmo 1000
[ 266.718249] agilent_82357a_generic_write: write aborted ibs 1, tmo 1000
[ 267.243967] /home/jan/PKGBUILDs/linux-gpib-svn/src/trunk/linux-gpib-kernel/drivers/gpib/agilent_82357a/agilent_82357a.c: agilent_82357a_generic_write: wait interrupted

Log ibterm:
Attempting to open /dev/gpib0
pad = 1, sad = 0, timeout = 10, send_eoi = 1, eos_mode = 0x0000
ibterm>*IDN?
ibterm error: Unable to write to device at pad 1

EBUS 14: Bus error