On Mon, 16 Mar 2009, Jean Delvare wrote: > On Mon, 16 Mar 2009 12:43:33 -0700 (PDT), Trent Piepho wrote: > > On Mon, 16 Mar 2009, Jean Delvare wrote: > > > Come on, just look at ir-kbd-i2c and tvaudio again, see how great are > > > these drivers which have been "designed" on top of the legacy i2c > > > binding model. Look at the bttv mess. Look at the zoran driver > > > conversion done by Hans a few weeks ago, which killed what, 3000 lines > > > of code? The old binding model was so bad that DVB doesn't even use it. > > > > IIRC, the zoran patch removed more like 1000 lines. > > You don't remember correctly: > 37 files changed, 4570 insertions(+), 7404 deletions(-) > That's 2834 lines. 1570 of which is for the removal of the saa7111 and > saa7114 and I agree this shouldn't count, so we're down to 1264 lines > removed. The removal of some "features" also shouldn't count but I > doubt it amounts to more than a few hundred lines. 1264 lines is "more like 1000 lines" than it is like 3000 lines! > In fact, to get a more accurate figure you can just look at the result > of my own conversion. There were two patches: > 13 files changed, 510 insertions(+), 625 deletions(-) > 11 files changed, 549 deletions(-) > This is -664 lines total. The exact number doesn't really matter. The > bottom line is that the new binding model requires significantly less > glue code than the legacy model. If you think some more about it, it > means a lot. Then how come the bttv patch added lines of code and a couple kB to the compiled driver size? > > But it also deleted > > v4l1 support, highmem support, and bigphys_area support. Maybe other > > things, Hans doesn't decribe his patches, so there's really no way to know > > what the zoran patch really did other than to weed through 10,000+ lines of > > diff which is mostly but not entirely moving blocks of code from one space > > to another and reindenting them. > > You are unfair. The pull request came with a short log of all the > changes. "short" log. His entire series was decribed with fewer words than I would use on a single patch that changes ten lines. > > If one includes the v4l1-compat module that is now providing v4l1 support > > (though it doesn't work correctly for zoran), the driver and the compat > > module are larger than the old driver was. Of course one can now turn off > > v4l1 support and get a smaller driver than before. And the v4l1 compat > > already existed and can be shared. But I think it's more correct to say > > the size reduction of the zoran driver was from removing features and not > > from v4l2_subdev. It seems like more of the the other subdev conversions > > have overall added more code than they removed. > > I am not familiar enough with this part of the code to say. But I guess > it doesn't really matter, as it wasn't my point anyway. It seems like your point was that conversions to v4l2_subdev allow drivers to be more efficient remove lots of code. The numbers I see just don't support that claim. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
