Re: OHCI_BE_FRAME_NO_SHIFT question

> IIRC, according to OHCI specs, frame number is a 16-bit value and is 
> padded with 2 zero bytes, as opposed to 32-bit value. Since it's a 
> 16-bit value, all be platforms should still have it in the first 2 bytes 
> (need the OHCI_BE_FRAME_NO_SHIFT).

Actually, in 7.3.3 the register holding the frame number is defined as
as a 32 bit register, with the low 16 bits holding that number.  But
nobody uses the reigster; the HCCA, in memory, is used.

The value stored in the HCCA is a 16 bit field at a specific offset,
but since not all CPUs can do 16 bit memory accesses it's used as a
32 bit field.  And that's why big-endian OHCI will shift 16 bits,
unless the vendor explicitly violates the spec...

- Dave

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel