xref: /freebsd/sys/contrib/device-tree/Bindings/pwm/atmel,hlcdc-pwm.yaml (revision 01950c46b8155250f64374fb72fc11faa44bf099)
1*01950c46SEmmanuel Vadot# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2*01950c46SEmmanuel Vadot%YAML 1.2
3*01950c46SEmmanuel Vadot---
4*01950c46SEmmanuel Vadot$id: http://devicetree.org/schemas/pwm/atmel,hlcdc-pwm.yaml#
5*01950c46SEmmanuel Vadot$schema: http://devicetree.org/meta-schemas/core.yaml#
6*01950c46SEmmanuel Vadot
7*01950c46SEmmanuel Vadottitle: Atmel's HLCDC's PWM controller
8*01950c46SEmmanuel Vadot
9*01950c46SEmmanuel Vadotmaintainers:
10*01950c46SEmmanuel Vadot  - Nicolas Ferre <nicolas.ferre@microchip.com>
11*01950c46SEmmanuel Vadot  - Alexandre Belloni <alexandre.belloni@bootlin.com>
12*01950c46SEmmanuel Vadot  - Claudiu Beznea <claudiu.beznea@tuxon.dev>
13*01950c46SEmmanuel Vadot
14*01950c46SEmmanuel Vadotdescription:
15*01950c46SEmmanuel Vadot  The LCDC integrates a Pulse Width Modulation (PWM) Controller. This block
16*01950c46SEmmanuel Vadot  generates the LCD contrast control signal (LCD_PWM) that controls the
17*01950c46SEmmanuel Vadot  display's contrast by software. LCDC_PWM is an 8-bit PWM signal that can be
18*01950c46SEmmanuel Vadot  converted to an analog voltage with a simple passive filter. LCD display
19*01950c46SEmmanuel Vadot  panels have different backlight specifications in terms of minimum/maximum
20*01950c46SEmmanuel Vadot  values for PWM frequency. If the LCDC PWM frequency range does not match the
21*01950c46SEmmanuel Vadot  LCD display panel, it is possible to use the standalone PWM Controller to
22*01950c46SEmmanuel Vadot  drive the backlight.
23*01950c46SEmmanuel Vadot
24*01950c46SEmmanuel Vadotproperties:
25*01950c46SEmmanuel Vadot  compatible:
26*01950c46SEmmanuel Vadot    const: atmel,hlcdc-pwm
27*01950c46SEmmanuel Vadot
28*01950c46SEmmanuel Vadot  "#pwm-cells":
29*01950c46SEmmanuel Vadot    const: 3
30*01950c46SEmmanuel Vadot
31*01950c46SEmmanuel Vadotrequired:
32*01950c46SEmmanuel Vadot  - compatible
33*01950c46SEmmanuel Vadot  - "#pwm-cells"
34*01950c46SEmmanuel Vadot
35*01950c46SEmmanuel VadotadditionalProperties: false
36