On Fri, Jun 03, 2011 at 12:21:50AM +0800, Barry Song wrote: > Arnd has required me to use device tree in our new SoC for the coming > upstream. so i am trying to define a property like clock = "uart" in > dts. then in drivers, > i get this string by: > clk = of_get_property(np, "clock", NULL); > then request this clock by clk_get().
This is entirely wrong. clk_get() takes two things. It takes a struct device. We should know what the struct device is (provided they're named in a stable manner.) The other parameter, the string, is up to the driver. It's not a device property. It's not a SoC-wide clock name. It's a connection name for the clock on the device. This won't change from one instance of the device to another instance of the device - it's effectively a constant. So there's no point in having the DT describe that name - that's out of its realm. One of the problems is that clk_get() hides the mapping of device+connection internally, which it has had to as we haven't had a device tree to look things up. In essence, clk_get() is looking up a property (the clock connection name) for the struct device. When clks get converted to the device tree, the DT stuff should hook inside clk_get() to do a property lookup to discover which clock the driver wants. Drivers should definitely not be looking up a property in the device tree and using that as a connection name into clk_get(). _______________________________________________ devicetree-discuss mailing list devicetree-discuss@lists.ozlabs.org https://lists.ozlabs.org/listinfo/devicetree-discuss
