On 10/28/2013 11:59 AM, Jan Lübbe wrote:
On Sat, 2013-10-26 at 15:46 +0300, Tero Kristo wrote:
On 10/26/2013 03:36 AM, Jan Lübbe wrote:
On Fri, 2013-10-25 at 18:57 +0300, Tero Kristo wrote:
+ mcasp0_fck: mcasp0_fck {
+ #clock-cells = <0>;
+ compatible = "fixed-factor-clock";
+ clocks = <&sys_clkin_ck>;
+ clock-mult = <1>;
+ clock-div = <1>;
+ };
+
+ mcasp1_fck: mcasp1_fck {
+ #clock-cells = <0>;
+ compatible = "fixed-factor-clock";
+ clocks = <&sys_clkin_ck>;
+ clock-mult = <1>;
+ clock-div = <1>;
+ };
What is you use case for these clocks with a fixed factor of 1? Wouldn't
it be simpler to just use sys_clkin_ck from the devices?
This is just kind of a dummy clock node for the driver use, so that it
is simpler for them to find their clocks. If these are dropped, the
drivers need to know that instead of their old own mcaspX_fck, they now
need to directly connect to sys_clkin_ck. This also allows to track
usecounts for the clocks better, if you don't have the mcaspX_fck:s for
example, you will just have a usecount of 25 for the sys_clkin_ck, but
don't really know who is using it. Also, other SoCs most likely have the
same name in use, so just to keep the clock data compatible across SoCs.
These files are also completely autogenerated from the existing clock
data under mach-omap2, and these nodes exist there.
But yea, no hard requirement.
We shouldn't add dummy clocks to simplify debugging, maybe we need some
user tracking in the core clk code?
Yea might be good to have something like this as configurable option in
the future, so you would know who has enabled a certain clock. Currently
clock APIs don't really provide way to tell users apart from each other.
Mike, any thoughts on this?
As there are only few of these factor 1 clocks, I'm fine with keeping
them for consistency here.
Thanks. :)
-Tero
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