On Tuesday 27 January 2015 14:19:09 Guenter Roeck wrote: > On Tue, Jan 27, 2015 at 10:29:49PM +0100, Arnd Bergmann wrote: > > On Tuesday 27 January 2015 12:52:29 Guenter Roeck wrote: > > > Driver does this (today): > > > > > > drvdata->rtc_clk = clk_get(&pdev->dev, "rtc"); > > > > > > Isn't that the name to use ? Just wondering. > > > > Just because the driver uses it at the moment does not mean it's the name > > that the IP block uses. > > > > clk_get() has the unpleasant property of doing fuzzy matching > > on the name that is passed. It first tries to use the string > > as the name of the clock input of the device, but if that is > > not there, it falls back to looking for a global clk with a con_id. > > > > In DT, we only support the first kind, but if a driver currently > > uses the second, you get the wrong name. > > > > Looking at arch/mips/jz4740/clock.c now, this seems to be exactly > > what is going on here: there is no clkdev_add call to associate > > the device clocks, so it can only match a global clock entry. > > > Me confused :-(. > > Does that mean the driver needs to be fixed, that the DT property > needs to change (to what ?), or both ? Both. The jz47xx clock driver should register a clkdev lookup table with proper clock input names for each clock that is referenced by a device, and then the drivers can use the right names. In a lot of cases, the best name for a clock is no name so you just use an anonymous clock like clk = clk_get(dev, NULL); but this still requires a clock lookup table. Arnd -- 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
