On Wed, 22 May 2013, Felipe Ferreri Tonello wrote: > Hi Guennadi, > > On Wednesday, May 22, 2013 10:30:40 PM Guennadi Liakhovetski wrote: > > On Wed, 22 May 2013, Felipe F. Tonello wrote: > > > From: "Felipe F. Tonello" <eu@xxxxxxxxxxxxxxxxx> > > > > > > This is useful for power managment purposes if a sdhci child host wants to > > > turn off some other peripheral also. > > > > Sorry, could you elaborate a bit? In what situations is it exactly useful? > > And why cannot the regulator API be used there? > > Sorry about that. > > One example that I can think of is when you have a wifi module connected as a > mmc card via sdio. So you can register a callback function in your machine > source code to turn on/off the wifi module based on the mmc host power. Ok, understand. Your second patch in this series adds such a callback in your SDHCI host driver and there it just calls a platform callback. I don't think this is a good idea. First, we want to go away from platform callbacks, because they are incompatible with DT. Second, because the proper solution IMHO would be for your platform to export a regulator, and the SDHCI core driver already includes regulator support. > I've seen this implementation in others mmc hosts, such as omap. Which, however, doesn't yet mean, it's a good idea :) Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
