Canon EOS E-TTL II Compatible Lenses
Since the early days of the EOS system, most of the lenses with ring USM motors have had the capability of returning focus distance information to the camera. Until the advent of the E-TTL II flash system, this distance information wasn't really used for anything.
E-TTL II is a flash algorithm which doesn't need distance information, but if it is available, under some circumstances it is used to fine tune flash exposure. You can read more about ETTL-II at http://www.bobatkins.com/photography/eosfaq/ettl2.html
E-TTL II differs from E-TTL in a number of ways, the use of distance info being just one of them. So if your lens doesn't return distance information don't worry about it too much as all the other features of ETTL-II will still work. All Canon EF series lenses work fine with camera bodies using E-TTL II flash exposure, but, as I mentioned above, the algorithm can't tweak exposure based on distance.
Most, but not all, USM lenses return distance information. Typically USM lenses which allow full time manual focus return distance info. However, although the 50/1.4 USM has full time manual focus and a USM motor, it's unique in that it has FTM but doesn't use a ring USM and so it doesn't return distance info. Currently the only 50mm lens that does return distance information is the new EF 50/1.2L. Not all lenses are listed here since, as far as I know, Canon have never issued a comprehensive list. It seems that all new lenses from Canon are capable of returing distance information. Most of the lenses that don't provide distance information are either very early lenses which were introduced shortly after the EOS ssytem was released or very low end consumer zoom "kit" lenses.
Though the lenses return the distance information to the camera body, that information does not seem to be recorded in digital image EXIF data by current cameras, at least not in any sort of easily accessible format. If it's there it certainly doesn't follow the EXIF standards and as far as I know, it's not there at all. Early DSLRs (EOS D60 and 10D for example) did record distance info in the EXIF data. I don't know why Canon dropped that feature.
The following is a list of Canon lenses which are known either to be capable of returning distance information or not capable of returning distance information. It probably doesn't include every lens Canon have ever made and lenses not listed here may or may not be ETTL-II compatible
(*) indicates the lens is no longer in production.
| Zooms returning distance information EF-S 10-22/3.5-4.5 USM
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Primes returning distance information EF 14/2.8L USM |
| Zooms NOT returning distance information EF 28-80/3.5-5.6 II |
Primes NOT returning distance information EF 15/2.8 fisheye |