Hi, Tomi Valkeinen wrote: > Hi, > > On Mon, 2010-09-20 at 22:18 +0200, ext Jorge Bustamante wrote: >> Hi, >> >> We (TI) have been working on a DSI video mode driver for OMAP4 and I > > I hope it's also for OMAP3? > >> am aware that other people are working with similar drivers. We had to >> tweak the code to make the drivers work with current code but we would >> like to make it the correct way, that is, introducing a proper >> functionality instead of inserting tweaks in the present command mode >> driver. Therefore, there is an initiative from us to modify current >> dss/dsi code to support DSI video mode. >> >> We have collected a list of requirements and ideas (with the help of >> ppl copied) from our experience working with these drivers, but it >> would be great if you can discuss/comment further on this. >> >> Requirements: >> >> - A better way of exposing VC's to a panel driver, since most panels >> use more than one VC. Currently the design supports only one per >> panel. Perhaps a VC resource pool could be created. > > Hmm, why would most panels use more than one VC? I haven't > seen a single one =). Command mode panels will work fine with a single VC, I don't think video mode can run by using only one VC. Also, for command mode, there isn't a restriction to use a single VC. If you configure one VC to have slave port as source and the other as video port, the need to switch the VC source between L4 and VP would go away. The most optimal way would be to use one VC for each peripheral, but I don't think the usecase of connecting 4 panels to the same DSI lanes would ever be needed. > > Nevertheless, it should be possible to use multiple VCs in one driver. > I've implemented a driver for a buffer chip that used all 4 channels. So did you connect more than one panel to DSI? I am curious about how it works [snip] >> >> - If we want a user to switch between modes, we may need to have a > > While I don't see any reason to forbid changing modes, I > don't see any real reason to implement switching between the > modes either. If it comes for free, sure, but if it means > lots of implementation, I'd rather leave it out. Or do you > have some use cases where switching modes is important? > There isn't any use case where we would use a panel for video mode and command mode at different points in time. But if the panel supports both video and command mode there should be some option (compile time/ boot time) to choose which mode is to be used. I guess its more for the sake of completeness of the panels capabilities. Regards, Archit -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
