On Tue, Feb 09, 2016 at 08:20:05AM +0100, Robert Jarzmik wrote: > Vinod Koul <vinod.koul@xxxxxxxxx> writes: > > > On Mon, Feb 08, 2016 at 03:18:51PM +0100, Robert Jarzmik wrote: > >> The current number of requestor lines is limited to 31. This was an > >> error of a previous commit, as this number is platform dependent, and is > >> actually : > >> - for pxa25x: 40 requestor lines > >> - for pxa27x: 74 requestor lines > >> - for pxa3xx: 100 requestor lines > >> > >> As the driver doesn't need to know the exact number, but only an > > > > and why would that be a good assumption? > Well, the driver doesn't use the exact value. Would that be 128, 1000 or 10000, > it wouldn't change its behavior. The clients either pass -1UL (ie. no flow > control) or a requestor line number. Somehow that does not sound right to me. You seem to have no way of knowing what is the actual max request line for a platforms. What if on pxa25x user requests more than 40 lines? > > Btw shouldn't this data come from DT? > It can if you wish, but in this case I must amend the platform data case too, ie > mmp_dma_platdata. And this has an impact on MMP architecture. I'd rather have > the simpler approach unless you really want the exact number of requestor lines > to be passed in platform_data+DT. The information that you have X lines on a platform needs to be described and queried. I see current approach error prone -- ~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
