[+Cc mailing list] Please, keep discussion public. On Wed, 2015-06-10 at 18:37 +0530, Shubham Kumar wrote: > Dear Andy, > > We have been trying to test the dmatest driver provided in the Kernel > Source tree on an Ubuntu 14.04 x86 based 64-bit machine. For the > documentations and help , We have referred to your dmatest.txt file > present inside the Documentations directory in the Kernel Source tree. > We have built the dmatest file as a module on kernel version 4.0.4 . > Then We also followed your steps on loading the module prescribed in > your Documentation file dmatest.txt. On doing > > > modprobe dmatest channel=dma0chan0 timeout=2000 iterations=1 run=1 > > and seeing the logs in the dmesg, We are getting the following error > logs which says that the channel allocation has failed- > > dmaengine: __dma_request_channel: fail ((null)) > > > We have attached the screenshot with this mail. > > On checking the available channel list from ls -l /sys/class/dma/ > , no channel is being shown. The same has been shown in the > screenshot. We also checked the /proc/dma entry, No entry is present > there. > > Some help in this direction ,for fixing this issue, would be appreciable. The main problem you have no channels to test. It would be caused by absence of DMA driver, misbehaving driver, or bugs in the driver's code. Until you have that folder (/sys/class/dma) empty you may not try dmatest, since it will do nothing. -- Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> Intel Finland Oy -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
