On 2018-09-04 00:25, Bjorn Andersson wrote:
On Wed 15 Aug 22:23 PDT 2018, kgunda@xxxxxxxxxxxxxx wrote:
On 2018-08-07 10:53, Bjorn Andersson wrote:
> On Mon 09 Jul 03:22 PDT 2018, Kiran Gunda wrote:
> > diff --git
> > a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
> > b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
> [..]
> > - qcom,num-strings
> > Usage: optional
> > Value type: <u32>
> > Definition: #; number of led strings attached;
> > - value from 1 to 3. default: 2
> > - This property is supported only for PM8941.
> > + value: For PM8941 from 1 to 3.
> > + For PMI8998 from 1 to 4.
> [..]
> > +- qcom,enabled-strings
> > + Usage: optional
> > + Value tyoe: <u32 array>
> > + Definition: Array of the WLED strings numbered from 0 to 3. Each
> > + string of leds are operated individually. Specify the
> > + list of strings used by the device. Any combination of
> > + led strings can be used.
> [..]
> >
> > Example:
> >
> > @@ -99,4 +146,5 @@ pm8941-wled@d800 {
> > qcom,switching-freq = <1600>;
> > qcom,ovp = <29>;
> > qcom,num-strings = <2>;
> > + qcom,enabled-strings = <0x00 0x01>;
>
> Nit. I would assume that specifying qcom,num-strings = <2> implies that
> the first 2 strings are used, so one would not also specify
> qcom,enabled-strings.
>
Thanks Bjorn for reviewing the series !
"qcom,enabled-strings" need be specified along with the
"qcom,num-strings".
Because the enabled-strings can be <0, 2> or <0, 3 > also. The driver
picks
the string
configuration from the enabled-strings array and enable only those
current-sinks.
The original binding described qcom,num-strings to mean "the first N
strings", requiring qcom,enabled-strings now would break backwards
compatibility with this binding.
In the case that qcom,enabled-strings is specified we can easily derive
num-strings from the listed entires. So I would suggest that you look
for enabled-strings and if not found fall back to checking for
num-strings.
Regards,
Bjorn
Sorry for the late reply. Actually the "qcom,enabled-strings" is
initialized with
the strings 0, 1, 2, 3 in the driver. Even though this property is
missing the first
N strings will be still configured with out any issue, based on the
"qcom,num-strings".
