diff options
Diffstat (limited to 'hw/misc/led.c')
| -rw-r--r-- | hw/misc/led.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/hw/misc/led.c b/hw/misc/led.c new file mode 100644 index 0000000..5266d02 --- /dev/null +++ b/hw/misc/led.c @@ -0,0 +1,161 @@ +/* + * QEMU single LED device + * + * Copyright (C) 2020 Philippe Mathieu-Daudé <f4bug@amsat.org> + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "migration/vmstate.h" +#include "hw/qdev-properties.h" +#include "hw/misc/led.h" +#include "hw/irq.h" +#include "trace.h" + +#define LED_INTENSITY_PERCENT_MAX 100 + +static const char * const led_color_name[] = { + [LED_COLOR_VIOLET] = "violet", + [LED_COLOR_BLUE] = "blue", + [LED_COLOR_CYAN] = "cyan", + [LED_COLOR_GREEN] = "green", + [LED_COLOR_AMBER] = "amber", + [LED_COLOR_ORANGE] = "orange", + [LED_COLOR_RED] = "red", +}; + +static bool led_color_name_is_valid(const char *color_name) +{ + for (size_t i = 0; i < ARRAY_SIZE(led_color_name); i++) { + if (strcmp(color_name, led_color_name[i]) == 0) { + return true; + } + } + return false; +} + +void led_set_intensity(LEDState *s, unsigned intensity_percent) +{ + if (intensity_percent > LED_INTENSITY_PERCENT_MAX) { + intensity_percent = LED_INTENSITY_PERCENT_MAX; + } + trace_led_set_intensity(s->description, s->color, intensity_percent); + if (intensity_percent != s->intensity_percent) { + trace_led_change_intensity(s->description, s->color, + s->intensity_percent, intensity_percent); + } + s->intensity_percent = intensity_percent; +} + +unsigned led_get_intensity(LEDState *s) +{ + return s->intensity_percent; +} + +void led_set_state(LEDState *s, bool is_emitting) +{ + led_set_intensity(s, is_emitting ? LED_INTENSITY_PERCENT_MAX : 0); +} + +static void led_set_state_gpio_handler(void *opaque, int line, int new_state) +{ + LEDState *s = LED(opaque); + + assert(line == 0); + led_set_state(s, !!new_state != s->gpio_active_high); +} + +static void led_reset(DeviceState *dev) +{ + LEDState *s = LED(dev); + + led_set_state(s, s->gpio_active_high); +} + +static const VMStateDescription vmstate_led = { + .name = TYPE_LED, + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT8(intensity_percent, LEDState), + VMSTATE_END_OF_LIST() + } +}; + +static void led_realize(DeviceState *dev, Error **errp) +{ + LEDState *s = LED(dev); + + if (s->color == NULL) { + error_setg(errp, "property 'color' not specified"); + return; + } else if (!led_color_name_is_valid(s->color)) { + error_setg(errp, "property 'color' invalid or not supported"); + return; + } + if (s->description == NULL) { + s->description = g_strdup("n/a"); + } + + qdev_init_gpio_in(DEVICE(s), led_set_state_gpio_handler, 1); +} + +static Property led_properties[] = { + DEFINE_PROP_STRING("color", LEDState, color), + DEFINE_PROP_STRING("description", LEDState, description), + DEFINE_PROP_BOOL("gpio-active-high", LEDState, gpio_active_high, true), + DEFINE_PROP_END_OF_LIST(), +}; + +static void led_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->desc = "LED"; + dc->vmsd = &vmstate_led; + dc->reset = led_reset; + dc->realize = led_realize; + set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories); + device_class_set_props(dc, led_properties); +} + +static const TypeInfo led_info = { + .name = TYPE_LED, + .parent = TYPE_DEVICE, + .instance_size = sizeof(LEDState), + .class_init = led_class_init +}; + +static void led_register_types(void) +{ + type_register_static(&led_info); +} + +type_init(led_register_types) + +LEDState *led_create_simple(Object *parentobj, + GpioPolarity gpio_polarity, + LEDColor color, + const char *description) +{ + g_autofree char *name = NULL; + DeviceState *dev; + + dev = qdev_new(TYPE_LED); + qdev_prop_set_bit(dev, "gpio-active-high", + gpio_polarity == GPIO_POLARITY_ACTIVE_HIGH); + qdev_prop_set_string(dev, "color", led_color_name[color]); + if (!description) { + static unsigned undescribed_led_id; + name = g_strdup_printf("undescribed-led-#%u", undescribed_led_id++); + } else { + qdev_prop_set_string(dev, "description", description); + name = g_ascii_strdown(description, -1); + name = g_strdelimit(name, " #", '-'); + } + object_property_add_child(parentobj, name, OBJECT(dev)); + qdev_realize_and_unref(dev, NULL, &error_fatal); + + return LED(dev); +} |