On Monday 23 January 2006 1:12 pm, Doug Sutherland wrote: > We would also like > to know what issues are involved in backporting this code from 2.6 to > 2.4.
On Monday, January 23, 2006 5:17 pm, David Brownell wrote: >I think the TTY layer changed enough to make a whole-driver backport >awkward, but the gadget APIs haven't changed appreciably. If you >want to get the CDC-ACM support, just backport those changes. >- Dave I've been looking at the differences between the 2.4 and 2.6 gadget serial drivers and there don't appear to be that many significant differences (outside of the new support for the CDC-ACM). There are a few TTY functions that aren't included in 2.4 (i.e. alloc_tty_driver(), tty_set_operations(), and put_tty_driver()), but it looks like these can easily be coded manually. The other main difference I see is the way the spinlock_t structure is passed to the spinlock functions. In the 2.4 version of the gadget serial driver, this structure is passed by value: spin_lock_irqsave( dev-dev_lock, flags ); In the 2.6 version, it seems to be passed by reference: spin_lock_irqsave(&dev->dev_lock, flags); I don't think I really understand the difference here and the 2.6 code isn't always consistent in this regard. Does anyone know what is going on with this spinlock issue? Is there a significant difference between 2.4 and 2.6 with regard to the spinlock processing? I see the spinlock.h files are very different between the two versions. Is this a real issue for my backporting of the gadget driver? My inclination on this backport effort is to simply use the latest version of the gadget serial driver and simply add manual code for the functions (e.g. tty functions mentioned above) that are not available in 2.4. Merging the CDC-ACM code back into the 2.4 version looks to be very difficult. If there are other issues, I'd appreciate hearing about them. Any advice would be appreciated. Doug ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid3432&bid#0486&dat1642 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
