On Thu, Oct 08, 2015 at 10:31:18AM +0200, Lars-Peter Clausen wrote: > > Basically I agree not to expose dma's quirk to slave controllers...But, the > > fact I mentioned on cover letter explain the reasons why I have to let slave > > controllers know that they are working with a broken dma. It's a dilemma > > that if we don't want that to be exposed(let slave controllers' driver get > > the info via a API), we have t add broken quirk for all of them ,here and > > there, which seems to be a disaster:( > > The problem with this API is that it transports values with device specific > meanings over a generic API. Which is generally speaking not a good idea > because the consumer witch is supposed to be generic suddenly needs to know > which provider it is talking to. > > A better solution in this case typically is either introduce a generic API > with generic values or a custom API with custom values, but don't mix the two. > > > > > I would appreciate it if you could give me some suggestions at your earliest > > convenience. :) > > In this case I think the best way to handle this is not quirks, but rather > expose the actual maximum burst size using the DMA capabilities API. Since > supporting only a certain burst depth is not really a quirk. All hardware > has a limit for this and for some it might be larger or smaller than for > others and it might be the same IP core but the maximum size depends on some > IP core parameters. So this should be discoverable. yes that makes more sense than adding quirks, exposing the right values which should be a readable property for driver will ensure it works on system with/without quirks -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
