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KSZ8795 SPI setup

Question asked by Ali Ismail on Oct 31, 2016
Latest reply on Nov 1, 2016 by Ali Ismail

Working on custom board with the imx6dqscm and we are trying to communicate with a ksz8795 switch through SPI. We have worked with a couple of drivers listed below:

 

KSZ8795 - Ethernet Switches 

http://lxr.free-electrons.com/source/drivers/net/phy/spi_ks8995.c

 

Everything seems to be configured correctly because we can see the correct clock signals and MOSI data going into the ksz8795. The only issue is that we are noticing that the chip select line is toggling between packets. We are thinking that this is terminating communication between the imx6 and the switch. I've looked in the RM and saw that there might be a potential wait state creating that delay, but I've checked that register and found 0 wait states. I am not sure what is causing the chip select to go high between packets. My questions are, what is causing this delay and how can I modify the driver to keep the SS low? I am just a little skeptical because these drivers are specific for this device, therefore, I must be missing something trivial.

 

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