On Thu, 23 Feb 2023, ChiaEn Wu wrote: > From: ChiYuan Huang <cy_huang@xxxxxxxxxxx> > > Document the MT6370 RGB LED pattern trigger. > > This simply describe how the pattern works, each timing period, and the > pattern diagram for MT6370 RGB LED. > > Signed-off-by: ChiYuan Huang <cy_huang@xxxxxxxxxxx> > Signed-off-by: ChiaEn Wu <chiaen_wu@xxxxxxxxxxx> > --- > Documentation/leds/leds-mt6370-rgb.rst | 64 ++++++++++++++++++++++++++++++++++ > 1 file changed, 64 insertions(+) > create mode 100644 Documentation/leds/leds-mt6370-rgb.rst > > diff --git a/Documentation/leds/leds-mt6370-rgb.rst b/Documentation/leds/leds-mt6370-rgb.rst > new file mode 100644 > index 00000000..d1b2e4f > --- /dev/null > +++ b/Documentation/leds/leds-mt6370-rgb.rst > @@ -0,0 +1,64 @@ > +.. SPDX-License-Identifier: GPL-2.0 > + > +========================================= > +Kernel driver for Mediatek MT6370 RGB LED Are you describing the device or the kernel driver? > +========================================= > + > +Description > +----------- > + > +The MT6370 integrates a four-channel RGB LED driver, designed to provide a > +variety of lighting effect for mobile device applications. The RGB LED driver "devices" > +includes a smart LED string controller and it can drive 3 channels of LEDs with > +a sink current up to 24mA and a CHG_VIN power good indicator LED with sink > +current up to 6mA. It provides three operation modes for RGB LEDs: > +PWM Dimming mode, breath pattern mode, and constant current mode. The device > +can increase or decrease the brightness of the RGB LED via I2C interface. "an I2C interface" > +The breath pattern for a channel can be programmed using the "pattern" trigger, > +using the hw_pattern attribute. > + > +/sys/class/leds/<led>/hw_pattern > +-------------------------------- > + > +Specify a hardware breath pattern for a MT6370 RGB LED. > + > +The breath pattern is a series of timing pairs, with the hold-time expressed in > +milliseconds. And the brightness is controlled by > +'/sys/class/leds/<led>/brightness'. The pattern doesn't include the brightness > +setting. Hardware pattern only controls the timing for each pattern stage > +depending on the current brightness setting. > + > +Pattern diagram:: > + > + "0 Tr1 0 Tr2 0 Tf1 0 Tf2 0 Ton 0 Toff" --> '0' for dummy brightness code > + > + ^ > + | ============ > + | / \ / > +Icurr | / \ / > + | / \ / > + | / \ / .....repeat > + | / \ / > + | --- --- --- > + |--- --- --- > + +----------------------------------============------------> Time > + < Tr1><Tr2>< Ton ><Tf1><Tf2 >< Toff >< Tr1><Tr2> > + > +Timing description:: > + > +Tr1: First rising time for duty 0 to 30%. > +Tr2: Second rising time for duty 31% to 100%. > +Ton: On time for duty 100%. > +Tf1: First falling time for duty 100% to 31%. > +Tf2: Second falling time for duty 30% to 0%. > +Toff: Off time for duty 0%. > + > +Tr1/Tr2/Tf1/Tf2/Ton: 125ms to 3125ms, 200ms per step. > +Toff: 250ms to 6250ms, 400ms per step. > + > +Pattern example:: > + > + "0 125 0 125 0 125 0 125 0 625 0 1050" > + > +This Will configure Tr1/Tr2/Tf1/Tf2 to 125m, Ton to 625ms, and Toff to 1050ms. > -- > 2.7.4 > -- Lee Jones [李琼斯]
