On 5 June 2016 at 14:55, 'Eckhardt Ulrich' via linux-sunxi <[email protected]> wrote: > > > Am Sonntag, 5. Juni 2016 13:45:59 UTC+2 schrieb Michal Suchanek:
> I have checked this with an oscilloscope (a cheap logic analyser is ordered > so that I could attach a better picture of the output of all pins hopefully > next week). I have written a small test program (attached to this message) > which sends repeatedly 4 bytes over the SPI bus using the ioctl. But on my > oscilloscope I could see only activities on the CS lines, but no change of > the CLK and MOSI outputs. Ok, so you checked with reasonable reliability that no data is actually transferred. Now to check that no data transfer is programmed - cherry pick from linus master 47284e3e0f3c427c93f8583549b6c938e8a18015 spi: sun4i: allow transfers to set transmission speed - cherry pick from https://github.com/hramrach/linux-sunxi.git branch sunxi-spi-dma cb90b922caa6ac07c1425d726ea19709ee5284f4 spi: sunxi: fix transfer timeout The latter adds a debug print in if(!timeout) so move the if below the debug print. In your test program change speed to 5kHz (5000) and change the ioctl to set the speed - iirc it should be SPI_IOC_WR_MAX_SPEED_HZ Then you should get a debug print on console every time your test program sends a message. If not something went wrong. HTH Michal -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
