On 02/18/2014 04:23 AM, Mark Rutland wrote:
> On Fri, Feb 14, 2014 at 04:43:04PM +0000, Stephen Warren wrote:
>> On 02/14/2014 03:35 AM, Mark Rutland wrote:
>>> On Fri, Feb 14, 2014 at 06:16:52AM +0000, Stephen Warren wrote:
>>>> 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@0 {
>>>> compatible = "fixed-clock";
>>>> reg = <0>;
>>>> ...
>>>> clk_i2c: clock@1 {
>>>> compatible = "fixed-clock";
>>>> reg = <1>;
>>>> ...
>>>> clk_spi: clock@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:-)
...
>>> 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@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.)
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