Hi Stephen, On Thu, 2015-06-04 at 14:02 -0700, Stephen Boyd wrote: > On 05/29, Sascha Hauer wrote: > > Yes. I previously got the impression that the subsystem clocks are not > > directly associated to the larbs, but needed to be handled by the larb > > code due to some side effect. Now that I saw that the larbs are directly > > in the subsystem register space it all makes sense. > > > > Note that the way Mediatek SoCs are designed around sub modules is bit > > unusual and does not fit very well in the Linux directory structure. > > Normally SoCs have a single clocks controller which controls all clocks > > in the SoC. Then you often have a reset controller providing reset lines > > in the SoC. In this case it's clear that the clk driver goes to > > drivers/clk/, the reset controller driver to drivers/reset/. Mediatek > > SoCs instead have several blocks, each with its own clock and reset > > controller. Splitting each block up into parts in drivers/clk/ and > > drivers/reset/ leads to quite a code fragmentation. > > This is my opinion, it would be great to hear something from others. > > Matthias? I'd like to avoid running into a direction that is not > > acceptable in the end. > > We already have drivers registering clocks and resets under > drivers/clk, so it's not unheard of. An alternative solution is > to make child devices for the clock part and the reset part at > runtime in the toplevel driver for the vencsys device (don't do > any sort of DT description for this) and use regmap to mediate > the register accesses and locking. That way we can put the clk > driver in drivers/clk/, the reset driver in drivers/reset, etc. > so that logically related code is grouped. I have a question about the alternative way you mentioned. Currently clock providers and consumers describe what clocks they will provide / consume in device tree. If we don't describe vencsys clocks in device tree, how to get vencsys clocks for drivers that need to control them? Best regards, James -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
