2020-10-21 05:56:14 +08:00
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.. _led_pwm:
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LED PWM sample application
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##########################
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Overview
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********
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This sample allows to test the led-pwm driver. The first "pwm-leds" compatible
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device instance found in DT is used. For each LEDs attached to this device
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(child nodes) the same test pattern (described below) is executed. The LED API
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functions are used to control the LEDs.
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Test pattern
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============
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For each PWM LEDs (one after the other):
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2021-01-15 23:26:02 +08:00
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- Turning on
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- Turning off
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- Increasing brightness gradually
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- Blinking on: 0.1 sec, off: 0.1 sec
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- Blinking on: 1 sec, off: 1 sec
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- Turning off
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2020-10-21 05:56:14 +08:00
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Building and Running
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********************
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This sample can be built and executed on all the boards with PWM LEDs connected.
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The LEDs must be correctly described in the DTS: the compatible property of the
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device node must match "pwm-leds". And for each LED, a child node must be
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defined and the PWM configuration must be provided through a "pwms" phandle's
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node.
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