Hello,
Recently, my usb-serial converter has become unusable. Attempts to open
the device always fail with:
open("/dev/ttyUSB0", O_RDONLY) = -1 EAGAIN (Resource temporarily unavailable)
The device is a:
ID 0c52:2101 Sealevel Systems, Inc. Serial Converter
and uses the ftdi_sio driver.
I've bisected this problem to
commit 1bfee5bc86fdaecc912e06080583eddab7263df2
Author: Alan Stern <[email protected]>
Date: Sat Sep 25 23:35:00 2010 +0200
PM / Runtime: Merge synchronous and async runtime routines
I have other usb-serial converters that use other drivers and that are
unaffected. I have noticed the problem on a x86_64 machine (.config
here: http://pastebin.ca/2006414) and can reproduce it in kvm (with usb
passthrough, .config here: http://pastebin.ca/2006416).
I'll be glad to provide more info or try patches.
Thanks,
-Ben
On Mon, Nov 29, 2010 at 08:52:14PM -0500, Benjamin Poirier wrote:
> Hello,
>
> Recently, my usb-serial converter has become unusable. Attempts to open
> the device always fail with:
> open("/dev/ttyUSB0", O_RDONLY) = -1 EAGAIN (Resource temporarily unavailable)
>
> The device is a:
> ID 0c52:2101 Sealevel Systems, Inc. Serial Converter
> and uses the ftdi_sio driver.
>
> I've bisected this problem to
> commit 1bfee5bc86fdaecc912e06080583eddab7263df2
> Author: Alan Stern <[email protected]>
> Date: Sat Sep 25 23:35:00 2010 +0200
>
> PM / Runtime: Merge synchronous and async runtime routines
>
> I have other usb-serial converters that use other drivers and that are
> unaffected. I have noticed the problem on a x86_64 machine (.config
> here: http://pastebin.ca/2006414) and can reproduce it in kvm (with usb
> passthrough, .config here: http://pastebin.ca/2006416).
>
> I'll be glad to provide more info or try patches.
A patch to resolve this was sent to [email protected] yesterday,
can you try that one out (sorry, can't dig it out at the moment...)
thanks,
greg k-h
On 29/11/10 10:26 PM, Greg KH wrote:
> On Mon, Nov 29, 2010 at 08:52:14PM -0500, Benjamin Poirier wrote:
>> Hello,
>>
>> Recently, my usb-serial converter has become unusable. Attempts to open
>> the device always fail with:
>> open("/dev/ttyUSB0", O_RDONLY) = -1 EAGAIN (Resource temporarily unavailable)
>>
>> The device is a:
>> ID 0c52:2101 Sealevel Systems, Inc. Serial Converter
>> and uses the ftdi_sio driver.
>>
>> I've bisected this problem to
>> commit 1bfee5bc86fdaecc912e06080583eddab7263df2
>> Author: Alan Stern <[email protected]>
>> Date: Sat Sep 25 23:35:00 2010 +0200
>>
>> PM / Runtime: Merge synchronous and async runtime routines
>>
>> I have other usb-serial converters that use other drivers and that are
>> unaffected. I have noticed the problem on a x86_64 machine (.config
>> here: http://pastebin.ca/2006414) and can reproduce it in kvm (with usb
>> passthrough, .config here: http://pastebin.ca/2006416).
>>
>> I'll be glad to provide more info or try patches.
>
> A patch to resolve this was sent to [email protected] yesterday,
> can you try that one out (sorry, can't dig it out at the moment...)
I think that's the one:
http://www.spinics.net/lists/linux-usb/msg39257.html
It indeed fixes the problem. Thanks!
btw. it seems I was late to the game, I should've checked bugzilla too,
https://bugzilla.kernel.org/show_bug.cgi?id=23012
-Ben
>
> thanks,
>
> greg k-h