qemu

FORK: QEMU emulator
git clone https://git.neptards.moe/neptards/qemu.git
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gpio_key.c (2888B)

      1 /*
      2  * GPIO key
      3  *
      4  * Copyright (c) 2016 Linaro Limited
      5  *
      6  * Author: Shannon Zhao <shannon.zhao@linaro.org>
      7  *
      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.
     11  *
     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.
     15  *
     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.
     20  *
     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/>.
     23  */
     24 
     25 #include "qemu/osdep.h"
     26 #include "hw/irq.h"
     27 #include "hw/sysbus.h"
     28 #include "migration/vmstate.h"
     29 #include "qemu/module.h"
     30 #include "qemu/timer.h"
     31 #include "qom/object.h"
     32 
     33 #define TYPE_GPIOKEY "gpio-key"
     34 OBJECT_DECLARE_SIMPLE_TYPE(GPIOKEYState, GPIOKEY)
     35 #define GPIO_KEY_LATENCY 100 /* 100ms */
     36 
     37 struct GPIOKEYState {
     38     SysBusDevice parent_obj;
     39 
     40     QEMUTimer *timer;
     41     qemu_irq irq;
     42 };
     43 
     44 static const VMStateDescription vmstate_gpio_key = {
     45     .name = "gpio-key",
     46     .version_id = 1,
     47     .minimum_version_id = 1,
     48     .fields = (VMStateField[]) {
     49         VMSTATE_TIMER_PTR(timer, GPIOKEYState),
     50         VMSTATE_END_OF_LIST()
     51     }
     52 };
     53 
     54 static void gpio_key_reset(DeviceState *dev)
     55 {
     56     GPIOKEYState *s = GPIOKEY(dev);
     57 
     58     timer_del(s->timer);
     59 }
     60 
     61 static void gpio_key_timer_expired(void *opaque)
     62 {
     63     GPIOKEYState *s = (GPIOKEYState *)opaque;
     64 
     65     qemu_set_irq(s->irq, 0);
     66     timer_del(s->timer);
     67 }
     68 
     69 static void gpio_key_set_irq(void *opaque, int irq, int level)
     70 {
     71     GPIOKEYState *s = (GPIOKEYState *)opaque;
     72 
     73     qemu_set_irq(s->irq, 1);
     74     timer_mod(s->timer,
     75               qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + GPIO_KEY_LATENCY);
     76 }
     77 
     78 static void gpio_key_realize(DeviceState *dev, Error **errp)
     79 {
     80     GPIOKEYState *s = GPIOKEY(dev);
     81     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
     82 
     83     sysbus_init_irq(sbd, &s->irq);
     84     qdev_init_gpio_in(dev, gpio_key_set_irq, 1);
     85     s->timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, gpio_key_timer_expired, s);
     86 }
     87 
     88 static void gpio_key_class_init(ObjectClass *klass, void *data)
     89 {
     90     DeviceClass *dc = DEVICE_CLASS(klass);
     91 
     92     dc->realize = gpio_key_realize;
     93     dc->vmsd = &vmstate_gpio_key;
     94     dc->reset = &gpio_key_reset;
     95 }
     96 
     97 static const TypeInfo gpio_key_info = {
     98     .name          = TYPE_GPIOKEY,
     99     .parent        = TYPE_SYS_BUS_DEVICE,
    100     .instance_size = sizeof(GPIOKEYState),
    101     .class_init    = gpio_key_class_init,
    102 };
    103 
    104 static void gpio_key_register_types(void)
    105 {
    106     type_register_static(&gpio_key_info);
    107 }
    108 
    109 type_init(gpio_key_register_types)