include/hw/misc/led.h

   1 /*
   2  * QEMU single LED device
   3  *
   4  * Copyright (C) 2020 Philippe Mathieu-Daudé <f4bug@amsat.org>
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8 #ifndef HW_MISC_LED_H
   9 #define HW_MISC_LED_H
  10
  11 #include "qom/object.h"
  12 #include "hw/qdev-core.h"
  13
  14 #define TYPE_LED "led"
  15
  16 /**
  17  * LEDColor: Color of a LED
  18  *
  19  * This set is restricted to physically available LED colors.
  20  *
  21  * LED colors from 'Table 1. Product performance of LUXEON Rebel Color
  22  * Line' of the 'DS68 LUXEON Rebel Color Line' datasheet available at:
  23  * https://www.lumileds.com/products/color-leds/luxeon-rebel-color/
  24  */
  25 typedef enum {          /* Coarse wavelength range */
  26     LED_COLOR_VIOLET,   /* 425 nm */
  27     LED_COLOR_BLUE,     /* 475 nm */
  28     LED_COLOR_CYAN,     /* 500 nm */
  29     LED_COLOR_GREEN,    /* 535 nm */
  30     LED_COLOR_YELLOW,   /* 567 nm */
  31     LED_COLOR_AMBER,    /* 590 nm */
  32     LED_COLOR_ORANGE,   /* 615 nm */
  33     LED_COLOR_RED,      /* 630 nm */
  34 } LEDColor;
  35
  36 struct LEDState {
  37     /* Private */
  38     DeviceState parent_obj;
  39     /* Public */
  40
  41     uint8_t intensity_percent;
  42     qemu_irq irq;
  43
  44     /* Properties */
  45     char *description;
  46     char *color;
  47     /*
  48      * Determines whether a GPIO is using a positive (active-high)
  49      * logic (when used with GPIO, the intensity at reset is related
  50      * to the GPIO polarity).
  51      */
  52     bool gpio_active_high;
  53 };
  54 typedef struct LEDState LEDState;
  55 DECLARE_INSTANCE_CHECKER(LEDState, LED, TYPE_LED)
  56
  57 /**
  58  * led_set_intensity: Set the intensity of a LED device
  59  * @s: the LED object
  60  * @intensity_percent: intensity as percentage in range 0 to 100.
  61  */
  62 void led_set_intensity(LEDState *s, unsigned intensity_percent);
  63
  64 /**
  65  * led_get_intensity:
  66  * @s: the LED object
  67  *
  68  * Returns: The LED intensity as percentage in range 0 to 100.
  69  */
  70 unsigned led_get_intensity(LEDState *s);
  71
  72 /**
  73  * led_set_state: Set the state of a LED device
  74  * @s: the LED object
  75  * @is_emitting: boolean indicating whether the LED is emitting
  76  *
  77  * This utility is meant for LED connected to GPIO.
  78  */
  79 void led_set_state(LEDState *s, bool is_emitting);
  80
  81 /**
  82  * led_create_simple: Create and realize a LED device
  83  * @parentobj: the parent object
  84  * @gpio_polarity: GPIO polarity
  85  * @color: color of the LED
  86  * @description: description of the LED (optional)
  87  *
  88  * Create the device state structure, initialize it, and
  89  * drop the reference to it (the device is realized).
  90  *
  91  * Returns: The newly allocated and instantiated LED object.
  92  */
  93 LEDState *led_create_simple(Object *parentobj,
  94                             GpioPolarity gpio_polarity,
  95                             LEDColor color,
  96                             const char *description);
  97
  98 #endif /* HW_MISC_LED_H */