Re: [PATCH v3 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Adriana Reus <adriana.reus-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

Thank you Jonathan, I'll add a new patch set soon, added some comments 
inline also.

Adriana
On 15.08.2015 17:31, Jonathan Cameron wrote:
> On 14/08/15 10:29, Adriana Reus wrote:
>> Added entries in trivial-devices and i2c/vendor-prefixes for
>> the us5182d als and proximity sensor. Also added a documentation file for
>> this sensor's properties.
>>
>> Signed-off-by: Adriana Reus <adriana.reus-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> It's not a trivial device if it has it's own docs.  So don't add it to that list
> (the point is to not have separate docs for devices that don't really have
> any device tree data other than where they are.
right, I'll add a new path set soon.
>
> Few more bits inline.
>> ---
>>    No changes - resending because I forgot to cc devicetree.
>>   .../devicetree/bindings/i2c/trivial-devices.txt    |  1 +
>>   .../devicetree/bindings/iio/light/us5182d.txt      | 24 ++++++++++++++++++++++
>>   .../devicetree/bindings/vendor-prefixes.txt        |  1 +
>>   3 files changed, 26 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/iio/light/us5182d.txt
>>
>> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> index 00f8652..96d3b9c 100644
>> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> @@ -99,4 +99,5 @@ ti,tsc2003		I2C Touch-Screen Controller
>>   ti,tmp102		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
>>   ti,tmp103		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
>>   ti,tmp275		Digital Temperature Sensor
>> +upisemi,usd5182		Als and Proximity Sensor
>>   winbond,wpct301		i2c trusted platform module (TPM)
>> diff --git a/Documentation/devicetree/bindings/iio/light/us5182d.txt b/Documentation/devicetree/bindings/iio/light/us5182d.txt
>> new file mode 100644
>> index 0000000..9ac3336
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/iio/light/us5182d.txt
>> @@ -0,0 +1,24 @@
>> +* UPISEMI us5182d I2C ALS and Proximity sensor
>> +
>> +Required properties:
>> +- compatible: must be "upisemi,usd5182"
>> +- reg: the I2C address of the device
>> +
>> +Optional properties:
>> +- upisemi,glass-coef: glass attenuation factor
>> +- upisemi,dark-ths: array of thresholds corresponding to every scale
> That needs more detail. I've read the driver and I am not sure what exactly
> you mean!  Why should a scale have a threshold?
I'll try to be more specific. These are values representing adc counts, 
that's why there are different values corresponding to every scale.
>> +- upisemi,upper-dark-gain: tuning factor applied when light > th
>> +- upisemi,lower-dark-gain: tuning factor applied when light < th
>> +
>> +Example:
>> +
>> +    usd5182@39 {
>> +                compatible = "upisemi,usd5182";
>> +                reg = <0x39>;
>> +                upisemi,glass-coef = < 1000 >;
>> +                upisemi,dark-ths = /bits/ 16 <170 200 512 512 800 2000 4000 8000>;
>> +                upisemi,upper-dark-gain = /bits/ 8 <0x00>;
>> +                upisemi,lower-dark-gain = /bits/ 8 <0x16>;
> Not sure why these are in hex.. Or why we care if they are 8 bits.  If there is a limit
> on the possible values, perhaps mention it in the docs above.
I should have been (much) more specific here: that represents a float 
number with 4 integer bits and 4 fractional bits (Q4.4), so I find hex 
more intuitive since it's split in half, let me know if you think 
otherwise. I'll add a more complete description. As for the "/bits/ x" 
it's because currently in the driver I use the read_property_u8 or *_u16 
functions, these require that the dts entry be as I wrote it in the 
example, and since it's an example it should be functional, so I feel 
that is ok as it is.
>
>
>> +    };
>> +
> One blank line at the end is neough.
>> +
>> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> index d444757..5b40bab 100644
>> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
>> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> @@ -211,6 +211,7 @@ toshiba	Toshiba Corporation
>>   toumaz	Toumaz
>>   tplink	TP-LINK Technologies Co., Ltd.
>>   truly	Truly Semiconductors Limited
>> +upisemi	uPI Semiconductor Corp.
>>   usi	Universal Scientific Industrial Co., Ltd.
>>   v3	V3 Semiconductor
>>   variscite	Variscite Ltd.
>>
>