2 Replies Latest reply on Jun 13, 2019 3:04 AM by deville

    Ultrazed-EV: Unable to locate the Infineon power chips. ( PMBUS )


      Hi Avnet,


      Currrently i'm tying to make a connection with all the I2C devices on the Ultrazed-EV board. I managed to reach the eeproms, the gpio extender and the i2C mux but i'm struggling to make this final I2C connection to the Infineon chips.


      I see all the chips via the Infineon software and the USB005 dongle which gives me a nice overview of the chips and their correlating  addresses ( image below )


      However I don't seem to manage to connect to them via the Zynqmp Linux root files system. The address 0x6a , which is the PLL chip behind the i2c mux, seems to been found by it's diver.  I think there should be 4 Infineon chips in this i2c region/channel (U18, U19 U21 end U22 )



      Can someone point out to me how I can make these infineon chips appear in the root file system?  Any help is very welcome..


      Thanks Deville

        • Re: Ultrazed-EV: Unable to locate the Infineon power chips. ( PMBUS )

          I found this solution rather quickly in the end.


          I must have used a device tree snippet from the zcu102 board or just made a plain mistake. Either way I used (the device tree ) compatible string  "nxp,pca9542" instead of the I2C chip used on the Ultrazed board.  "pca9543" 

          Both devices are using the same driver  ( drivers/i2c/muxes/i2c-mux-pca954x.c ) but the pca9542 chip is a mux, while pca9543 is in fact a switch. This mixup caused the driver to treat the device differently, trying to set a mux channel ( value 0x04 )


          Now I have my devices:


          Thanks Avnet !

            • Re: Ultrazed-EV: Unable to locate the Infineon power chips. ( PMBUS )

              Another Issue popped up after finding the previous solution. On the UltraZed-EV board there are some Infineon chips with PMBUS capabilities present like i mentioned at the start of this thread.


              These chips have no drivers present in my kernel ( 4.14 ) so I used the generic PMBUS driver. However there should be some PMBUS Sysfs entries present once booted but this seems not to be working.


              All I get is:

              [zynqmp@zynqmp ~ ]$ dmesg | grep pmbus
              [    1.475625] pmbus 1-004b: PMBus status register not found
              [    1.475921] pmbus 1-004c: PMBus status register not found
              [    1.476212] pmbus 1-0049: PMBus status register not found
              [    1.476503] pmbus 1-004a: PMBus status register not found
              [    1.490635] pmbus 2-0046: No attributes found
              [    1.504554] pmbus 2-0047: No attributes found
              [    1.520525] pmbus 2-0048: No attributes found


              Can you give me any advice on this issue Avnet?  Should I be doing my own readout from userspace? ( I can do readouts and manipulations via the I2C tools )


              Thanks in advance