On 2018-07-19 09:26, Caprioru, Mircea wrote:
> On Wed, 2018-07-18 at 15:09 +0200, Peter Rosin wrote:
>> On 2018-07-17 15:44, Mircea Caprioru wrote:
>>> Adding dt-bindings documentation for adgs1408/1409 multiplexer. The
>>> bindings follow the standard SPI and mux bindings and do not
>>> require any
>>> additional custom properties.
>>
>> However, both chips have general purpose output pins. I think it is
>> customary to document the bindings for such things while at it?
>
> This functionality is not yet implemented in the driver. It does not
> make sense to document it just yet. Will add it when the driver
> implements it.
I disagree, and I also think 2/2 should come before 1/2, just to show
that things are done in the proper order. That makes it clear that the
driver does not implement random (or not yet existing) device-tree
bindings.
The bindings should not document the driver, they should document
the hardware/interfaces.
>>
>> Another thing that I'm wondering about is if it is at all possible
>> to describe daisy-chained devices on an spi bus in the device tree?
>>
> I'm not sure about this either. I will have to also look into this.
It was more of a general question for devicetree/spi experts, but I do
not expect any generic solutions in this problem space...
Cheers,
Peter
>>>
>>> Signed-off-by: Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>
>>> ---
>>> Changelog V1 -> V2
>>> - removed wildcard adgs140x
>>> - removed removed required cells property
>>>
>>> .../devicetree/bindings/mux/adi,adgs1408.txt | 39
>>> +++++++++++++++++++
>>> MAINTAINERS | 1 +
>>> 2 files changed, 40 insertions(+)
>>> create mode 100644
>>> Documentation/devicetree/bindings/mux/adi,adgs1408.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/mux/adi,adgs1408.txt
>>> b/Documentation/devicetree/bindings/mux/adi,adgs1408.txt
>>> new file mode 100644
>>> index 000000000000..6b1cbe326786
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/mux/adi,adgs1408.txt
>>> @@ -0,0 +1,39 @@
>>> +Bindings for Analog Devices ADGS1408/1409 8:1/Dual 4:1 Mux
>>> +
>>> +Required properties:
>>> +- compatible : "adi,adgs1408" or "adi,adgs1409"
>>
>> I think it is preferred to have one compatible per line.
>
> Ack.
>>
>>> +* Standard mux-controller bindings as described in mux-
>>> controller.txt
>>> +
>>> +Optional properties:
>>> +- idle-state : if present, array of states that the mux
>>> controllers will have
>>> + when idle. The special state MUX_IDLE_AS_IS is the default and
>>> + MUX_IDLE_DISCONNECT is also supported.
>>> +
>>> +States 0 through 7 correspond to signals S1 through S8 in the
>>> datasheet.
>>> +For ADGS1409 only states 0 to 3 are available.
>>> +
>>> +Example:
>>> +
>>> + /*
>>> + * One mux controller.
>>> + * Mux 1 to 8 set to idle as is (no idle-state declared)
>>
>> What do you mean "Mux 1 to 8"? There is only one mux...
>
> I was reffering to the mux inputs, will rephrase this.
>>
>>> + */
>>> + &spi0 {
>>> + mux: mux-controller@2 {
>>> + compatible = "adi,adgs1408";
>>> + reg = <0>;
>>
>> reg = <0> does not match @2 above.
>
> Ack.
>>
>>> + spi-max-frequency = <1000000>;
>>> + #mux-control-cells = <0>;
>>> + };
>>> + }
>>> +
>>> + adc-mux@3 {
>>
>> There is no reg property in this node. I think you should simply
>> drop the @3.
>
> Ack.
>>
>> Cheers,
>> Peter
>
> Thanks,
> Mircea
>>
>>> + compatible = "io-channel-mux";
>>> + io-channels = <&adc 1>;
>>> + io-channel-names = "parent";
>>> + mux-controls = <&mux>;
>>> +
>>> + channels = "out_a0", "out_a1", "test0", "test1",
>>> + "out_b0", "out_b1", "testb0", "testb1";
>>> +
>>> + };
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index 458d42d6f4f3..af8ea2638641 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -814,6 +814,7 @@ ANALOG DEVICES INC ADGS1408 DRIVER
>>> M: Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>
>>> S: Supported
>>> F: drivers/mux/adgs1408.c
>>> +F: Documentation/devicetree/bindings/mux/adi,adgs1408.txt
>>>
>>> ANALOG DEVICES INC ADV7180 DRIVER
>>> M: Lars-Peter Clausen <lars@xxxxxxxxxx>
>>>
>>
--
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
