Add a LED device which can be connected to a GPIO output.
They can also be dimmed with PWM devices. For now we do
not implement the dimmed mode, but in preparation of a
future implementation, we start using the LED intensity.
LEDs are limited to a fixed set of colors.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
include/hw/misc/led.h | 84 +++++++++++++++++++++++++
hw/misc/led.c | 142 ++++++++++++++++++++++++++++++++++++++++++
MAINTAINERS | 6 ++
hw/misc/Kconfig | 3 +
hw/misc/meson.build | 1 +
hw/misc/trace-events | 3 +
6 files changed, 239 insertions(+)
create mode 100644 include/hw/misc/led.h
create mode 100644 hw/misc/led.c
diff --git a/include/hw/misc/led.h b/include/hw/misc/led.h
new file mode 100644
index 00000000000..1aaabbebafc
--- /dev/null
+++ b/include/hw/misc/led.h
@@ -0,0 +1,84 @@
+/*
+ * QEMU single LED device
+ *
+ * Copyright (C) 2020 Philippe Mathieu-Daudé <f4bug@amsat.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef HW_MISC_LED_H
+#define HW_MISC_LED_H
+
+#include "hw/qdev-core.h"
+
+#define TYPE_LED "led"
+#define LED(obj) OBJECT_CHECK(LEDState, (obj), TYPE_LED)
+
+/**
+ * LEDColor: Color of a LED
+ *
+ * This set is restricted to physically available LED colors.
+ *
+ * LED colors from 'Table 1. Product performance of LUXEON Rebel Color
+ * Line' of the 'DS68 LUXEON Rebel Color Line' datasheet available at:
+ * https://www.lumileds.com/products/color-leds/luxeon-rebel-color/
+ */
+typedef enum { /* Coarse wavelength range */
+ LED_COLOR_VIOLET, /* 425 nm */
+ LED_COLOR_BLUE, /* 475 nm */
+ LED_COLOR_CYAN, /* 500 nm */
+ LED_COLOR_GREEN, /* 535 nm */
+ LED_COLOR_AMBER, /* 590 nm */
+ LED_COLOR_ORANGE, /* 615 nm */
+ LED_COLOR_RED, /* 630 nm */
+} LEDColor;
+
+typedef struct LEDState {
+ /* Private */
+ DeviceState parent_obj;
+ /* Public */
+
+ uint8_t intensity_percent;
+
+ /* Properties */
+ char *description;
+ char *color;
+} LEDState;
+
+/**
+ * led_set_intensity: set the intensity of a LED device
+ * @s: the LED object
+ * @intensity: intensity as percentage in range 0 to 100.
+ * @color: color of the LED
+ * @description: description of the LED (optional)
+ *
+ * Create the device state structure, initialize it, and
+ * drop the reference to it (the device is realized).
+ */
+LEDState *led_create_simple(Object *parentobj,
+ LEDColor color,
+ const char *description);
+
+#endif /* HW_MISC_LED_H */
diff --git a/hw/misc/led.c b/hw/misc/led.c
new file mode 100644
index 00000000000..f2140739b68
--- /dev/null
+++ b/hw/misc/led.c
@@ -0,0 +1,142 @@
+/*
+ * 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 "trace.h"
+
+#define LED_INTENSITY_PERCENT_MAX 100
+
+static const char *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 (led_color_name[i] && 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);
+ 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_reset(DeviceState *dev)
+{
+ LEDState *s = LED(dev);
+
+ led_set_state(s, false);
+}
+
+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");
+ }
+}
+
+static Property led_properties[] = {
+ DEFINE_PROP_STRING("color", LEDState, color),
+ DEFINE_PROP_STRING("description", LEDState, description),
+ 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,
+ LEDColor color,
+ const char *description)
+{
+ g_autofree char *name = NULL;
+ DeviceState *dev;
+
+ dev = qdev_new(TYPE_LED);
+ 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);
+}
diff --git a/MAINTAINERS b/MAINTAINERS
index b233da2a737..d040846b868 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1951,6 +1951,12 @@ F: docs/specs/vmgenid.txt
F: tests/qtest/vmgenid-test.c
F: stubs/vmgenid.c
+LED
+M: Philippe Mathieu-Daudé <f4bug@amsat.org>
+S: Maintained
+F: include/hw/misc/led.h
+F: hw/misc/led.c
+
Unimplemented device
M: Peter Maydell <peter.maydell@linaro.org>
R: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index 92c397ca07a..5c151fa3a83 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -126,6 +126,9 @@ config AUX
config UNIMP
bool
+config LED
+ bool
+
config MAC_VIA
bool
select MOS6522
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index e1576b81cf9..26f6dd037dc 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -11,6 +11,7 @@ softmmu_ss.add(when: 'CONFIG_TMP105', if_true:
files('tmp105.c'))
softmmu_ss.add(when: 'CONFIG_TMP421', if_true: files('tmp421.c'))
softmmu_ss.add(when: 'CONFIG_UNIMP', if_true: files('unimp.c'))
softmmu_ss.add(when: 'CONFIG_EMPTY_SLOT', if_true: files('empty_slot.c'))
+softmmu_ss.add(when: 'CONFIG_LED', if_true: files('led.c'))
# ARM devices
softmmu_ss.add(when: 'CONFIG_PL310', if_true: files('arm_l2x0.c'))
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 066752aa900..76c9ddb54fe 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -214,6 +214,9 @@ via1_adb_poll(uint8_t data, const char *vadbint, int
status, int index, int size
grlib_ahb_pnp_read(uint64_t addr, uint32_t value) "AHB PnP read addr:0x%03"PRIx64"
data:0x%08x"
grlib_apb_pnp_read(uint64_t addr, uint32_t value) "APB PnP read addr:0x%03"PRIx64"
data:0x%08x"
+# led.c
+led_set_intensity(const char *color, const char *desc, uint8_t intensity_percent)
"LED desc:'%s' color:%s intensity: %u%%"
+
# pca9552.c
pca955x_gpio_status(const char *description, const char *buf) "%s GPIOs 0-15
[%s]"
pca955x_gpio_change(const char *description, unsigned id, unsigned prev_state, unsigned
current_state) "%s GPIO id:%u status: %u -> %u"