On Wed, 25 Jan 2012, Sarah Sharp wrote: > Somehow we ended up with duplicate hub feature #defines in ch11.h. > Tatyana Brokhman first created the USB 3.0 hub feature macros in 2.6.38 > with commit 0eadcc09203349b11ca477ec367079b23d32ab91 "usb: USB3.0 ch11 > definitions". In 2.6.39, I modified a patch from John Youn that added > similar macros in a different place in the same file, and committed > dbe79bbe9dcb22cb3651c46f18943477141ca452 "USB 3.0 Hub Changes". > > Some of the #defines used different names for the same values. Others > used exactly the same names with the same values, like these gems: > > #define USB_PORT_FEAT_BH_PORT_RESET 28 > ... > #define USB_PORT_FEAT_BH_PORT_RESET 28 > > According to my very geeky husband (who looked it up in the C99 spec), > it is allowed to have object-like macros with duplicate names as long as > the replacement list is exactly the same. However, he recalled that > some compilers will give warnings when they find duplicate macros. It's > probably best to remove the duplicates in the stable tree, so that the > code compiles for everyone. > > The macros are now fixed to move the feature requests that are specific > to USB 3.0 hubs into a new section (out of the USB 2.0 hub feature > section), and use the most common macro name. > > This patch should be backported to 2.6.39. This is fine, but notice that some of the port status-change bits have names that don't agree with the names in the USB-3.0 spec. For example, we have USB_PORT_STAT_C_LINK_STATE, whereas the spec talks about C_PORT_LINK_STATE. Do you want to change these names too, or do you not care about them? Or does it seem redudant to include "_PORT" twice in the same name? (Although you did just touch the definition of USB_PORT_FEAT_C_PORT_LINK_STATE.) Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
