On Tue, 23 Aug 2011 14:41:57 +0100, Jonathan Cameron wrote > On 08/23/11 14:24, malas wrote: > > On Tue, 23 Aug 2011 13:58:34 +0100, Jonathan Cameron wrote > >> On 08/23/11 13:43, malas wrote: > >>> YES : Gregs updated kernel taken from link below: > >>> > >>> http://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6.git > >> Right now that's pretty much mainline. > >> > >> See comments below and please reply inline as it makes this sort > >> of discussion much easier to follow. > >>> > >>> > >>> On Tue, 23 Aug 2011 13:39:12 +0100, Jonathan Cameron wrote > >>>> On 08/23/11 13:17, malas wrote: > >>>>> > >>>>> > >>>>> Sorry, I did not explicitly mention that. I did use the new staging kernel referred by > >>>>> Michael Hennerich and integrated with 2010RC5 uclinux dist . > >>>> > >>>> Hmm. As in current contents of Greg KH's staging/staging-next? > >>>> > >>>> I'll assume so... See below. > >>>> > >>>>> > >>>>> On Tue, 23 Aug 2011 12:39:53 +0100, Hennerich, Michael wrote > >>>>>> malas wrote on 2011-08-23: > >>>>>>> > >>>>>>> > >>>>>>> Dear Jonathan Cameron, > >>>>>>> > >>>>>>> The kernel version I am using is : > >>>>>> > >>>>>> Didn't you say that you use the staging kernel? > >>>>>> > >>>>>> > >>>>> > >>> > > http://blackfin.uclinux.org/gf/project/uclinux-dist/forum/?_forum_action=MessageReply&message_id=102839&action=ForumBrowse > >>>>>> > >>>>>> Or copied drivers/staging/iio over to your Blackfin kernel tree? > >>>>>> > >>>>>>> > >>>>>>> --------------------------------------------------------------------- > >>>>>>> midas@ubuntu:~/Mala/Telemedicine/uclinux_source/uc2010_source/uclinux/2 > >>>>>>> 010R1$ svn info Path: . URL: > >>>>>>> svn://blackfin.uclinux.org/uclinux-dist/branches/2010R1 Repository Root: > >>>>>>> svn://blackfin.uclinux.org/uclinux-dist Repository UUID: > >>>>>>> 3e2a5524-39e8-4cb9-84a9-c49da69cba3a Revision: 10161 Node Kind: > >>>>>>> directory Schedule: normal Last Changed Author: vapier Last Changed Rev: > >>>>>>> 10136 Last Changed Date: 2011-04-02 22:36:15 +0530 (Sat, 02 Apr 2011) > >>>>>>> --------------------------------------------------------------------- > >>>>>>> > >>>>>>> Regards > >>>>>>> Mala > >>>>>>> > >>>>>>> On Tue, 23 Aug 2011 12:21:25 +0100, Jonathan Cameron wrote > >>>>>>>> On 08/23/11 09:18, malas wrote: > >>>>>>>>> > >>>>>>>>> Dear Michael Hennerich, > >>>>>>>>> > >>>>>>>>> > >>>>>>>>> I shall post iio quesris in this mail list as per your suggestions. > >>>>>>>>> > >>>>>>>>> AD7793 driver is built into kernel. The chip gets configured and am > >>>>>>>>> able to read data on continuous mode via spi interface using ad7793 > >>>>>>>>> driver at kernel level. > >>>>>>>>> > >>>>>>>>> While testing userspace test iio-ring to read data from ring buffer, > >>>>>>>>> generic_buffer code was executed, it proceeds till opening > >>>>>>>>> /sys/bus/iio/devices/device0:buffer0 and Read call fails. > >>>>>>>> Question 1: What's the kernel and where did you get it from? > >>>>>>>> (Interfaces are moving fast so it's plausible you've fallen in a hole > >>>>>>>> where userspace wasn't matching kernelspace). > >>>>>>>>> > >>>>>>>>> In fs I can list the iio device ad7793 with following properties > >>>>>>>>> get/set. > >>>>>>>>> > >>>>>>>>> root:/> ls /sys/bus/iio/devices/device0\:buffer0/ > >>>>>>>>> bytes_per_datum enable power subsystem > >>>>>>>>> dev length scan_elements uevent > >>>>>>>>> root:/> > >>>>>>>>> > >>>>>>>>> I find access0 and event0 missing in this list. Is that the reason > >>>>>>> for read() fails. > >>>>>>>> Yes. Question is why and without kernel version I don't know where to > >>>>>>>> look I'm afraid. > >>>> Ah, this does look like a missmatch in interfaces between userspace and kernel. > >>>> > >>>> At this point in time we have scrapped the event0 chrdev (done via polling on > >>>> the access one) and the access one has be flattened into device0\:buffer0/ > >>>> (read dev). > >>>> > >>>> Looks like the generic_buffer.c example does line up though. Where did the > >>>> 'test iio-ring' come from? Is that one yours Michael? > > > > > > iio-ring.c under uclinux2010/user/blkfin-test/iio-ring-test. The file is in the > > attached. I did not use that since i didn't find access0 or event0 files under > > /sys/bus/iio/devices/device0:buffer0. > > > > I have tested with the generic_buffer.c example (under iio/documentaion folder) to get > > Ad7793 received samples to user space from ring buffer. > > The app opens: /dev/device0:buffer0 for poll and reading samples. > > Is the device name for the open() correct. > Yes - that should be right. ************************* Open fails for "/dev/device0:buffer0" device name I tried changing to "/sys/bus/iio/devices/device0:buffer0"- open() succeeded then but then read fails. -mala ************************* -- Open WebMail Project (http://openwebmail.org) -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
