4 * Copyright (c) 2016 Linaro Limited
6 * Author: Shannon Zhao <shannon.zhao@linaro.org>
8 * Emulate a (human) keypress -- when the key is triggered by
9 * setting the incoming gpio line, the outbound irq line is
10 * raised for 100ms before being dropped again.
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License; either version 2
14 * of the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License along
22 * with this program; if not, see <http://www.gnu.org/licenses/>.
25 #include "qemu/osdep.h"
26 #include "hw/sysbus.h"
28 #define TYPE_GPIOKEY "gpio-key"
29 #define GPIOKEY(obj) OBJECT_CHECK(GPIOKEYState, (obj), TYPE_GPIOKEY)
30 #define GPIO_KEY_LATENCY 100 /* 100ms */
32 typedef struct GPIOKEYState {
33 SysBusDevice parent_obj;
39 static const VMStateDescription vmstate_gpio_key = {
42 .minimum_version_id = 1,
43 .fields = (VMStateField[]) {
44 VMSTATE_TIMER_PTR(timer, GPIOKEYState),
49 static void gpio_key_reset(DeviceState *dev)
51 GPIOKEYState *s = GPIOKEY(dev);
56 static void gpio_key_timer_expired(void *opaque)
58 GPIOKEYState *s = (GPIOKEYState *)opaque;
60 qemu_set_irq(s->irq, 0);
64 static void gpio_key_set_irq(void *opaque, int irq, int level)
66 GPIOKEYState *s = (GPIOKEYState *)opaque;
68 qemu_set_irq(s->irq, 1);
70 qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + GPIO_KEY_LATENCY);
73 static void gpio_key_realize(DeviceState *dev, Error **errp)
75 GPIOKEYState *s = GPIOKEY(dev);
76 SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
78 sysbus_init_irq(sbd, &s->irq);
79 qdev_init_gpio_in(dev, gpio_key_set_irq, 1);
80 s->timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, gpio_key_timer_expired, s);
83 static void gpio_key_class_init(ObjectClass *klass, void *data)
85 DeviceClass *dc = DEVICE_CLASS(klass);
87 dc->realize = gpio_key_realize;
88 dc->vmsd = &vmstate_gpio_key;
89 dc->reset = &gpio_key_reset;
92 static const TypeInfo gpio_key_info = {
94 .parent = TYPE_SYS_BUS_DEVICE,
95 .instance_size = sizeof(GPIOKEYState),
96 .class_init = gpio_key_class_init,
99 static void gpio_key_register_types(void)
101 type_register_static(&gpio_key_info);
104 type_init(gpio_key_register_types)