Hi all, This is the third version of this RFC. The first can be found here: http://comments.gmane.org/gmane.linux.drivers.video-input-infrastructure/44285 The second was never posted. Changes since RFCv1: Incorporated comments from Mauro: - Renamed V4L2_DV_FL_NTSC_COMPATIBLE to V4L2_DV_FL_CAN_REDUCE_FPS - Renamed V4L2_DV_FL_DIVIDE_CLOCK_BY_1_001 to V4L2_DV_FL_REDUCED_FPS - Use kernel-doc-nano comments - Added a feature-removal document for the invalid DV presets Others: - I removed the patch adding format matching functions to v4l2-common.c. That's postponed until there is a driver that actually needs it. If there are no more comments, then this can be merged for v3.5. Once that's done I'll work on adding support for this to drivers that use the preset API so that we can deprecate and eventually remove the preset API. The text of the original RFCv1 follows: ------------------------------------------------------------------------ This is an implementation of this RFC: http://www.mail-archive.com/linux-media@xxxxxxxxxxxxxxx/msg38168.html The goal is that with these additions the existing DV_PRESET API can be removed eventually. It's always painful to admit, but that wasn't the best API ever :-) To my dismay I discovered that some of the preset defines were even impossible: there are no interlaced 1920x1080i25/29.97/30 formats. I have been testing this new code with the adv7604 HDMI receiver as used here: http://git.linuxtv.org/hverkuil/cisco.git/shortlog/refs/heads/test-timings This is my development/test branch, so the code is a bit messy. One problem that I always had with the older proposals is that there was no easy way to just select a specific standard (e.g. 720p60). By creating the linux/v4l2-dv-timings.h header this is now very easy to do, both for drivers and applications. I also took special care on how to distinguish between e.g. 720p60 and 720p59.94. See the documentation for more information. Note that the QUERY_DV_TIMINGS and DV_TIMINGS_CAP ioctls will be marked experimental. Particularly the latter ioctl might well change in the future as I do not have enough experience to tell whether DV_TIMINGS_CAP is sufficiently detailed. I would like to get some feedback on this approach, just to make sure I don't need to start over. In the meantime I will be working on code to detect CVT and GTF video timings since that is needed to verify that that part works correctly as well. And once everyone agrees to the API, then I will try and add this API to all drivers that currently use the preset API. That way there will be a decent path forward to eventually remove the preset API (sooner rather than later IMHO). Regards, Hans -- 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
