On 25/11/15 23:55, Rob Herring wrote: > On Wed, Nov 25, 2015 at 11:50:30AM +0200, Adriana Reus wrote: >> >> >> On 25.11.2015 02:01, Rob Herring wrote: >>> On Tue, Nov 24, 2015 at 12:59:49PM +0200, Adriana Reus wrote: >>>> Add a property to allow changing the default power-saving mode. >>>> By default, at read raw the chip will activate and provide >>>> one measurent, then it will shut itself down. However, the >>>> chip can also work in "continuous" mode which may be more reliable >>>> but is also more power consuming. >>>> >>>> Signed-off-by: Adriana Reus <adriana.reus@xxxxxxxxx> >>>> --- >>>> Documentation/devicetree/bindings/iio/light/us5182d.txt | 11 +++++++++++ >>>> 1 file changed, 11 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/iio/light/us5182d.txt b/Documentation/devicetree/bindings/iio/light/us5182d.txt >>>> index 6f0a530..a619799 100644 >>>> --- a/Documentation/devicetree/bindings/iio/light/us5182d.txt >>>> +++ b/Documentation/devicetree/bindings/iio/light/us5182d.txt >>>> @@ -7,13 +7,24 @@ Required properties: >>>> Optional properties: >>>> - upisemi,glass-coef: glass attenuation factor - compensation factor of >>>> resolution 1000 for material transmittance. >>>> + >>>> - upisemi,dark-ths: array of 8 elements containing 16-bit thresholds (adc >>>> counts) corresponding to every scale. >>>> + >>>> - upisemi,upper-dark-gain: 8-bit dark gain compensation factor(4 int and 4 >>>> fractional bits - Q4.4) applied when light > threshold >>>> + >>>> - upisemi,lower-dark-gain: 8-bit dark gain compensation factor(4 int and 4 >>>> fractional bits - Q4.4) applied when light < threshold >>>> >>>> +- upisemi,continuous: This chip has two power modes: one-shot (chip takes one >>>> + measurement and then shuts itself down) and continuous ( >>>> + chip takes continuous measurements). The one-shot mode is >>>> + more power-friendly but the continuous mode may be more >>>> + reliable. If this property is specified the continuous >>>> + mode will be used instead of the default one-shot one for >>>> + raw reads. >>> >>> I could imagine an OS may want to decide this on its own or use a >>> mixture of the modes. >>> >>> Rob >>> >> >> There is no possibility of mixing them up (at the same time), so for example >> proximity cannot work in one mode and als the other. >> >> The one-shot mode can only be used for raw reads (for example when >> user-space polls in_[proximity|light]_raw). If user-space wants to enable >> events (activate interrupts when certain thresholds are met - patch 5 of the >> series), then the chip has to switch to continuous nonetheless because it >> needs to be active all the time. So one work-flow scenario would be: >> >> Consumer1 starts polling the raw interface - default_mode >> Consumer2 activates events - continuous mode >> Consumer2 deactivates events - back to default_mode >> >> The only choice here is the default mode for raw reads, it currently is >> one-shot, this patch allows for continuous to be used if preferred. > > Okay, then: > > Acked-by: Rob Herring <robh@xxxxxxxxxx> Applied to the togreg branch of iio.git - initially pushed out as testing. Thanks, Jonathan > >> -- >> 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 > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- 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
