• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 98 subscribers
  • Views 394 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Any OHCI Expert? Problems in restarting USB OHCI controller after completely shutting it down.

Mughees Chohan
Intellectual 530 points
Other Parts Discussed in Thread: OMAPL138

Hi,

We have written the driver for OHCI controller on omapl138 for our proprietary RTOS. The driver works great but we have a problem if we try to restart the complete controller after completely shutting it down (all clocks off, module off in its power domain) for saving power. Here is what we do when we shutdown the controller:

1. Disable all interrupts of OHCI.

2. Write 0 to HCCONTROL register.

3. Reset the controller in HCCOMMANDSTATUS register.

4.  Stop the all the USB 2.0 clocks since USB1.1 clocks is sourced from this in my case.

5. Turn off USB 1.1 in LPSC1 power domain.

Now when we restart, we re-enable all the clocks, USB1.1 power and proceed with OHCI configuration as it is done at system startup (at startup the controller works but not after shutting OHCI down and restarting). Now when I connect a usb device I don't get any interrupt whatsoever. Am I missing something? Thank You.

Regards,

Mughees

  • 0
    TI__Mastermind 43955 points

    Hi Mughees,

    The USB Host controller driver was already available for OMAPL138.

    Please have a look at the Starterware pacakge which encloses the Host side and peripheral side USB drivers.

    All the below host side drivers are the tested and working ones on OMApl138 LCDK. I would recommend you to either re-use or compare the sequence with yours.

    1. usb_host_kb

    2. usb_host_mouse

    3. usb_host_msc

    Regards,

    Shankari

    -------------------------------------------------------------------------------------------------------

    Please click the Verify Answer button on this post if it answers your question.

    --------------------------------------------------------------------------------------------------------