| Message ID | 1467010990-28070-2-git-send-email-florian.vaussard@heig-vd.ch |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
Hi Florian, On 06/27/2016 09:03 AM, Florian Vaussard wrote: > Add device tree binding documentation for On Semiconductor NCP5623 I2C > LED driver. The driver can independently control the PWM of the 3 > channels with 32 levels of intensity. > > The current delivered by the current source can also be controlled. To > do so, the led-max-microamp property is used by each LED sub-node. The > maximum value is then found and used as a limit to compute the final > intensity of the current source. If a LED happens to have a lower limit, > the PWM is then used to limit the current to the requested value. > > In order to control the current source, it is also necessary to know > the current on the Iref pin, hence the onnn,led-iref-microamp property. > It is usually set using an external bias resistor, following > Iref = Vref/Rbias with Vref=0.6V. > > Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch> > --- > .../devicetree/bindings/leds/leds-ncp5623.txt | 60 ++++++++++++++++++++++ > 1 file changed, 60 insertions(+) > create mode 100644 Documentation/devicetree/bindings/leds/leds-ncp5623.txt > > diff --git a/Documentation/devicetree/bindings/leds/leds-ncp5623.txt b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt > new file mode 100644 > index 0000000..77dd7ad > --- /dev/null > +++ b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt > @@ -0,0 +1,60 @@ > +* ON Semiconductor - NCP5623 3-Channel LED Driver > + > +The NCP5623 is a 3-channel I2C LED driver. The brightness of each > +channel can be independently set using 32 levels. Each LED is represented > +as a sub-node of the device. > + > +Required properties: > + - compatible: Should be "onnn,ncp5623" > + - reg: I2C slave address (fixed to 0x38) > + - #address-cells: must be 1 > + - #size-cells: must be 0 > + - onnn,led-iref-microamp: Current on the Iref pin in microampere. It depends > + on the value of the external bias resistor Rbias, following > + Iref = Vref / Rbias with Vref = 0.6V. This is used to set the intensity of > + the current that can be provided by the internal current source, based on > + the maximum current permitted by LED sub-nodes (see below), but no more than > + Imax = 2400 * Iref. > + > +LED sub-nodes > +============= > + > +Required properties: > + - reg : LED channel number (0..2) > + - led-max-microamp: Maximum allowable current inside the LED in microampere. > + This property is used to limit the PWM ratio, based on the intensity of the > + internal current source (see above). > + > +Optional properties: > + - label: Used for naming LEDs Instead of the above description use same reference to common led bindings as below. > + - default-trigger: see Documentation/devicetree/bindings/leds/common.txt > + > +Example > +======= > + > +led1: ncp5623@38 { > + #address-cells = <1>; > + #size-cells = <0>; > + compatible = "onnn,ncp5623"; > + reg = <0x38>; > + onnn,led-iref-microamp = <10>; > + > + led1r@0 { > + label = "ncp:power:red"; > + linux,default-trigger = "default-on"; > + reg = <0>; > + led-max-microamp = <20000>; > + }; > + > + led1b@1 { > + label = "ncp:power:blue"; > + reg = <1>; > + led-max-microamp = <20000>; > + }; > + > + led1g@2 { > + label = "ncp:power:green"; > + reg = <2>; > + led-max-microamp = <20000>; > + }; > +}; >
Hi Jacek, Le 27. 06. 16 à 10:11, Jacek Anaszewski a écrit : > Hi Florian, > > On 06/27/2016 09:03 AM, Florian Vaussard wrote: >> Add device tree binding documentation for On Semiconductor NCP5623 I2C >> LED driver. The driver can independently control the PWM of the 3 >> channels with 32 levels of intensity. >> >> The current delivered by the current source can also be controlled. To >> do so, the led-max-microamp property is used by each LED sub-node. The >> maximum value is then found and used as a limit to compute the final >> intensity of the current source. If a LED happens to have a lower limit, >> the PWM is then used to limit the current to the requested value. >> >> In order to control the current source, it is also necessary to know >> the current on the Iref pin, hence the onnn,led-iref-microamp property. >> It is usually set using an external bias resistor, following >> Iref = Vref/Rbias with Vref=0.6V. >> >> Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch> >> --- >> .../devicetree/bindings/leds/leds-ncp5623.txt | 60 ++++++++++++++++++++++ >> 1 file changed, 60 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/leds/leds-ncp5623.txt >> >> diff --git a/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >> b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >> new file mode 100644 >> index 0000000..77dd7ad >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >> @@ -0,0 +1,60 @@ >> +* ON Semiconductor - NCP5623 3-Channel LED Driver >> + >> +The NCP5623 is a 3-channel I2C LED driver. The brightness of each >> +channel can be independently set using 32 levels. Each LED is represented >> +as a sub-node of the device. >> + >> +Required properties: >> + - compatible: Should be "onnn,ncp5623" >> + - reg: I2C slave address (fixed to 0x38) >> + - #address-cells: must be 1 >> + - #size-cells: must be 0 >> + - onnn,led-iref-microamp: Current on the Iref pin in microampere. It depends >> + on the value of the external bias resistor Rbias, following >> + Iref = Vref / Rbias with Vref = 0.6V. This is used to set the intensity of >> + the current that can be provided by the internal current source, based on >> + the maximum current permitted by LED sub-nodes (see below), but no more than >> + Imax = 2400 * Iref. >> + >> +LED sub-nodes >> +============= >> + >> +Required properties: >> + - reg : LED channel number (0..2) >> + - led-max-microamp: Maximum allowable current inside the LED in microampere. >> + This property is used to limit the PWM ratio, based on the intensity of the >> + internal current source (see above). >> + >> +Optional properties: >> + - label: Used for naming LEDs > > Instead of the above description use same reference to common led > bindings as below. > Ok. BTW I saw the thread about the "default-state" property on the DT list and realized that it was not implemented in my driver. I wonder if standard LED properties (with label and default-trigger) should not be parsed by LED core (i.e. using a helper function) to avoid such mistake. This could also remove some boilerplate code in other LED drivers. Best, Florian >> + - default-trigger: see Documentation/devicetree/bindings/leds/common.txt >> + >> +Example >> +======= >> + >> +led1: ncp5623@38 { >> + #address-cells = <1>; >> + #size-cells = <0>; >> + compatible = "onnn,ncp5623"; >> + reg = <0x38>; >> + onnn,led-iref-microamp = <10>; >> + >> + led1r@0 { >> + label = "ncp:power:red"; >> + linux,default-trigger = "default-on"; >> + reg = <0>; >> + led-max-microamp = <20000>; >> + }; >> + >> + led1b@1 { >> + label = "ncp:power:blue"; >> + reg = <1>; >> + led-max-microamp = <20000>; >> + }; >> + >> + led1g@2 { >> + label = "ncp:power:green"; >> + reg = <2>; >> + led-max-microamp = <20000>; >> + }; >> +}; >> > > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 06/27/2016 10:30 AM, Florian Vaussard wrote: > Hi Jacek, > > Le 27. 06. 16 à 10:11, Jacek Anaszewski a écrit : >> Hi Florian, >> >> On 06/27/2016 09:03 AM, Florian Vaussard wrote: >>> Add device tree binding documentation for On Semiconductor NCP5623 I2C >>> LED driver. The driver can independently control the PWM of the 3 >>> channels with 32 levels of intensity. >>> >>> The current delivered by the current source can also be controlled. To >>> do so, the led-max-microamp property is used by each LED sub-node. The >>> maximum value is then found and used as a limit to compute the final >>> intensity of the current source. If a LED happens to have a lower limit, >>> the PWM is then used to limit the current to the requested value. >>> >>> In order to control the current source, it is also necessary to know >>> the current on the Iref pin, hence the onnn,led-iref-microamp property. >>> It is usually set using an external bias resistor, following >>> Iref = Vref/Rbias with Vref=0.6V. >>> >>> Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch> >>> --- >>> .../devicetree/bindings/leds/leds-ncp5623.txt | 60 ++++++++++++++++++++++ >>> 1 file changed, 60 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>> >>> diff --git a/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>> b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>> new file mode 100644 >>> index 0000000..77dd7ad >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>> @@ -0,0 +1,60 @@ >>> +* ON Semiconductor - NCP5623 3-Channel LED Driver >>> + >>> +The NCP5623 is a 3-channel I2C LED driver. The brightness of each >>> +channel can be independently set using 32 levels. Each LED is represented >>> +as a sub-node of the device. >>> + >>> +Required properties: >>> + - compatible: Should be "onnn,ncp5623" >>> + - reg: I2C slave address (fixed to 0x38) >>> + - #address-cells: must be 1 >>> + - #size-cells: must be 0 >>> + - onnn,led-iref-microamp: Current on the Iref pin in microampere. It depends >>> + on the value of the external bias resistor Rbias, following >>> + Iref = Vref / Rbias with Vref = 0.6V. This is used to set the intensity of >>> + the current that can be provided by the internal current source, based on >>> + the maximum current permitted by LED sub-nodes (see below), but no more than >>> + Imax = 2400 * Iref. >>> + >>> +LED sub-nodes >>> +============= >>> + >>> +Required properties: >>> + - reg : LED channel number (0..2) >>> + - led-max-microamp: Maximum allowable current inside the LED in microampere. >>> + This property is used to limit the PWM ratio, based on the intensity of the >>> + internal current source (see above). >>> + >>> +Optional properties: >>> + - label: Used for naming LEDs >> >> Instead of the above description use same reference to common led >> bindings as below. >> > > Ok. > > BTW I saw the thread about the "default-state" property on the DT list and > realized that it was not implemented in my driver. I wonder if standard LED > properties (with label and default-trigger) should not be parsed by LED core > (i.e. using a helper function) to avoid such mistake. This could also remove > some boilerplate code in other LED drivers. Yes, generic DT parser is a nice-to-have feature for the LED subsystem. Would you like to implement it? > >>> + - default-trigger: see Documentation/devicetree/bindings/leds/common.txt >>> + >>> +Example >>> +======= >>> + >>> +led1: ncp5623@38 { >>> + #address-cells = <1>; >>> + #size-cells = <0>; >>> + compatible = "onnn,ncp5623"; >>> + reg = <0x38>; >>> + onnn,led-iref-microamp = <10>; >>> + >>> + led1r@0 { >>> + label = "ncp:power:red"; >>> + linux,default-trigger = "default-on"; >>> + reg = <0>; >>> + led-max-microamp = <20000>; >>> + }; >>> + >>> + led1b@1 { >>> + label = "ncp:power:blue"; >>> + reg = <1>; >>> + led-max-microamp = <20000>; >>> + }; >>> + >>> + led1g@2 { >>> + label = "ncp:power:green"; >>> + reg = <2>; >>> + led-max-microamp = <20000>; >>> + }; >>> +}; >>> >> >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-leds" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > >
Le 27. 06. 16 à 10:33, Jacek Anaszewski a écrit : > On 06/27/2016 10:30 AM, Florian Vaussard wrote: >> Hi Jacek, >> >> Le 27. 06. 16 à 10:11, Jacek Anaszewski a écrit : >>> Hi Florian, >>> >>> On 06/27/2016 09:03 AM, Florian Vaussard wrote: >>>> Add device tree binding documentation for On Semiconductor NCP5623 I2C >>>> LED driver. The driver can independently control the PWM of the 3 >>>> channels with 32 levels of intensity. >>>> >>>> The current delivered by the current source can also be controlled. To >>>> do so, the led-max-microamp property is used by each LED sub-node. The >>>> maximum value is then found and used as a limit to compute the final >>>> intensity of the current source. If a LED happens to have a lower limit, >>>> the PWM is then used to limit the current to the requested value. >>>> >>>> In order to control the current source, it is also necessary to know >>>> the current on the Iref pin, hence the onnn,led-iref-microamp property. >>>> It is usually set using an external bias resistor, following >>>> Iref = Vref/Rbias with Vref=0.6V. >>>> >>>> Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch> >>>> --- >>>> .../devicetree/bindings/leds/leds-ncp5623.txt | 60 >>>> ++++++++++++++++++++++ >>>> 1 file changed, 60 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>>> b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>>> new file mode 100644 >>>> index 0000000..77dd7ad >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt >>>> @@ -0,0 +1,60 @@ >>>> +* ON Semiconductor - NCP5623 3-Channel LED Driver >>>> + >>>> +The NCP5623 is a 3-channel I2C LED driver. The brightness of each >>>> +channel can be independently set using 32 levels. Each LED is represented >>>> +as a sub-node of the device. >>>> + >>>> +Required properties: >>>> + - compatible: Should be "onnn,ncp5623" >>>> + - reg: I2C slave address (fixed to 0x38) >>>> + - #address-cells: must be 1 >>>> + - #size-cells: must be 0 >>>> + - onnn,led-iref-microamp: Current on the Iref pin in microampere. It depends >>>> + on the value of the external bias resistor Rbias, following >>>> + Iref = Vref / Rbias with Vref = 0.6V. This is used to set the intensity of >>>> + the current that can be provided by the internal current source, based on >>>> + the maximum current permitted by LED sub-nodes (see below), but no more >>>> than >>>> + Imax = 2400 * Iref. >>>> + >>>> +LED sub-nodes >>>> +============= >>>> + >>>> +Required properties: >>>> + - reg : LED channel number (0..2) >>>> + - led-max-microamp: Maximum allowable current inside the LED in microampere. >>>> + This property is used to limit the PWM ratio, based on the intensity of >>>> the >>>> + internal current source (see above). >>>> + >>>> +Optional properties: >>>> + - label: Used for naming LEDs >>> >>> Instead of the above description use same reference to common led >>> bindings as below. >>> >> >> Ok. >> >> BTW I saw the thread about the "default-state" property on the DT list and >> realized that it was not implemented in my driver. I wonder if standard LED >> properties (with label and default-trigger) should not be parsed by LED core >> (i.e. using a helper function) to avoid such mistake. This could also remove >> some boilerplate code in other LED drivers. > > Yes, generic DT parser is a nice-to-have feature for the LED subsystem. > Would you like to implement it? > Sure, if it can be useful. I will have a look in the coming days. Best, Florian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Jun 27, 2016 at 10:11:04AM +0200, Jacek Anaszewski wrote: > Hi Florian, > > On 06/27/2016 09:03 AM, Florian Vaussard wrote: > >Add device tree binding documentation for On Semiconductor NCP5623 I2C > >LED driver. The driver can independently control the PWM of the 3 > >channels with 32 levels of intensity. > > > >The current delivered by the current source can also be controlled. To > >do so, the led-max-microamp property is used by each LED sub-node. The > >maximum value is then found and used as a limit to compute the final > >intensity of the current source. If a LED happens to have a lower limit, > >the PWM is then used to limit the current to the requested value. > > > >In order to control the current source, it is also necessary to know > >the current on the Iref pin, hence the onnn,led-iref-microamp property. > >It is usually set using an external bias resistor, following > >Iref = Vref/Rbias with Vref=0.6V. > > > >Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch> > >--- > > .../devicetree/bindings/leds/leds-ncp5623.txt | 60 ++++++++++++++++++++++ > > 1 file changed, 60 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/leds/leds-ncp5623.txt > > > >diff --git a/Documentation/devicetree/bindings/leds/leds-ncp5623.txt b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt > >new file mode 100644 > >index 0000000..77dd7ad > >--- /dev/null > >+++ b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt > >@@ -0,0 +1,60 @@ > >+* ON Semiconductor - NCP5623 3-Channel LED Driver > >+ > >+The NCP5623 is a 3-channel I2C LED driver. The brightness of each > >+channel can be independently set using 32 levels. Each LED is represented > >+as a sub-node of the device. > >+ > >+Required properties: > >+ - compatible: Should be "onnn,ncp5623" > >+ - reg: I2C slave address (fixed to 0x38) > >+ - #address-cells: must be 1 > >+ - #size-cells: must be 0 > >+ - onnn,led-iref-microamp: Current on the Iref pin in microampere. It depends > >+ on the value of the external bias resistor Rbias, following > >+ Iref = Vref / Rbias with Vref = 0.6V. This is used to set the intensity of > >+ the current that can be provided by the internal current source, based on > >+ the maximum current permitted by LED sub-nodes (see below), but no more than > >+ Imax = 2400 * Iref. > >+ > >+LED sub-nodes > >+============= > >+ > >+Required properties: > >+ - reg : LED channel number (0..2) > >+ - led-max-microamp: Maximum allowable current inside the LED in microampere. > >+ This property is used to limit the PWM ratio, based on the intensity of the > >+ internal current source (see above). > >+ > >+Optional properties: > >+ - label: Used for naming LEDs > > Instead of the above description use same reference to common led > bindings as below. > > >+ - default-trigger: see Documentation/devicetree/bindings/leds/common.txt And this is missing the linux prefix. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/leds/leds-ncp5623.txt b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt new file mode 100644 index 0000000..77dd7ad --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-ncp5623.txt @@ -0,0 +1,60 @@ +* ON Semiconductor - NCP5623 3-Channel LED Driver + +The NCP5623 is a 3-channel I2C LED driver. The brightness of each +channel can be independently set using 32 levels. Each LED is represented +as a sub-node of the device. + +Required properties: + - compatible: Should be "onnn,ncp5623" + - reg: I2C slave address (fixed to 0x38) + - #address-cells: must be 1 + - #size-cells: must be 0 + - onnn,led-iref-microamp: Current on the Iref pin in microampere. It depends + on the value of the external bias resistor Rbias, following + Iref = Vref / Rbias with Vref = 0.6V. This is used to set the intensity of + the current that can be provided by the internal current source, based on + the maximum current permitted by LED sub-nodes (see below), but no more than + Imax = 2400 * Iref. + +LED sub-nodes +============= + +Required properties: + - reg : LED channel number (0..2) + - led-max-microamp: Maximum allowable current inside the LED in microampere. + This property is used to limit the PWM ratio, based on the intensity of the + internal current source (see above). + +Optional properties: + - label: Used for naming LEDs + - default-trigger: see Documentation/devicetree/bindings/leds/common.txt + +Example +======= + +led1: ncp5623@38 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "onnn,ncp5623"; + reg = <0x38>; + onnn,led-iref-microamp = <10>; + + led1r@0 { + label = "ncp:power:red"; + linux,default-trigger = "default-on"; + reg = <0>; + led-max-microamp = <20000>; + }; + + led1b@1 { + label = "ncp:power:blue"; + reg = <1>; + led-max-microamp = <20000>; + }; + + led1g@2 { + label = "ncp:power:green"; + reg = <2>; + led-max-microamp = <20000>; + }; +};
Add device tree binding documentation for On Semiconductor NCP5623 I2C LED driver. The driver can independently control the PWM of the 3 channels with 32 levels of intensity. The current delivered by the current source can also be controlled. To do so, the led-max-microamp property is used by each LED sub-node. The maximum value is then found and used as a limit to compute the final intensity of the current source. If a LED happens to have a lower limit, the PWM is then used to limit the current to the requested value. In order to control the current source, it is also necessary to know the current on the Iref pin, hence the onnn,led-iref-microamp property. It is usually set using an external bias resistor, following Iref = Vref/Rbias with Vref=0.6V. Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch> --- .../devicetree/bindings/leds/leds-ncp5623.txt | 60 ++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/leds-ncp5623.txt