[PATCH 1/2] clk: fixed-rate: use full DT node name

On 02/18/2014 04:23 AM, Mark Rutland wrote:

On Fri, Feb 14, 2014 at 04:43:04PM +0000, Stephen Warren wrote:

quoted

On 02/14/2014 03:35 AM, Mark Rutland wrote:

quoted

On Fri, Feb 14, 2014 at 06:16:52AM +0000, Stephen Warren wrote:

quoted

clk-fixed-rate currently names clocks according to a node's name without
the unit address. When faced with the legal and technically correct DT
structure below, this causes rgistration attempts for 3 clocks with the
same name, 2 of which fail.

	clocks {
		compatible = "simple-bus";
		#address-cells = <1>;
		#size-cells = <0>;

		clk_mmc: clock at 0 {
			compatible = "fixed-clock";
			reg = <0>;
...
		clk_i2c: clock at 1 {
			compatible = "fixed-clock";
			reg = <1>;
...
		clk_spi: clock at 2 {
			compatible = "fixed-clock";
			reg = <2>;
...

I'd argue that this case isn't valid.

Well, it's very widely used, and was the result of numerous discussions
of how this kind of thing should be represented:-/

Maybe we have to live with it then. :/

Great:-)

...

quoted

quoted

It's just nonsensical; rename them to clock_{0,1,..} instead and get rid
of the reg properties. Then they're named uniquely.

That's not legal either. DT node names are supposed to represent the
type of device/object (i.e. just "clock"), not the identity of the
device/object (i.e. not include IDs etc.). Hence, the node name needs to
be "clock" for all of them, and the unit address must be used to
differentiate them.

As far as I can see from ePAPR, the only requriement is:

  The node-name shall start with a lower or uppercase character and
  should describe the general class of device.

IMO clock_1 describes the general class of device as well as clock at 1,
while also not filling a unexpected property with a meaningless value.

I believe section 2.2.2 "Generic Names Recommendation" is the source of
the rule that nodes should be named after the type of object rather than
the identity.

"""
The name of a node should be somewhat generic, reflecting the function
of the device and not its precise programming model. If appropriate, the
name should be one of the following choices:

* atm
* cache-controller
* compact-flash
* can
* cpu
...
"""

(I note e.g. "cpu" not "cpu-1", "cpu_2", etc.)