0 Replies Latest reply on Jan 17, 2018 8:50 AM by kripashree

    i2c reads 0xff all the time

    kripashree

      Hi,

      I am facing one problem while doing i2cset and i2cget.
      I am using AMD MF bettong DDR4 board.
      kernel version is : 4.4.11-158-amd+

      I am doing i2cset works fine.
      But i2cget reads 0xff all the time.

      commands used is:
      sudo i2cset -y 6 0x50 0x6c 00
      sudo i2cget -y 6 0x50 0x6c

      i2cdump also reads 0xff all the time irrespective of the value written!!!

      cae@cae-Bettong:~$ sudo i2cdump 6 0x50
      No size specified (using byte-data access)
      WARNING! This program can confuse your I2C bus, cause data loss and worse!
      I will probe file /dev/i2c-6, address 0x50, mode byte
      Continue? [Y/n] y
      0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef
      00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      10: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      20: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      30: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      40: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      50: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      60: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      70: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      90: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      a0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      b0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      c0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      d0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      e0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      f0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
      cae@cae-Bettong:~$

      Please let me know why i am not able to write to EEPROM?

      I am using one i2c test application to receive i2c 1 or 2 bytes.After running which only i2c slave will be attached to i2c bus!

      Before running the application i2c slave is not attached to the bus! why?

      And also running the application changes the register values,which is read using printk() in the driver.

      That time also i2cdump or i2cget reads 0xff !!!!

      Why is this happening?? can anyone please let me know?

      Thanks & Regards,
      Kripashree