diff options
author | Shannon Zhao <shannon.zhao@linaro.org> | 2016-03-30 17:27:22 +0100 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2016-03-30 17:27:22 +0100 |
commit | e5a8152c9bfd3d40c37711ba5b704f277cbc0c54 (patch) | |
tree | f934ee17be4817f0f357bafa37dc498f3048ffd0 /hw/gpio/gpio_key.c | |
parent | 489ef4c810033e63af570c8a430af8b9858bfa5f (diff) |
hw/gpio: Add the emulation of gpio_key
This will be used by ARM virt machine as a power button.
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Message-id: 1458221140-15232-2-git-send-email-zhaoshenglong@huawei.com
[PMM: Use hyphen rather than underscore in type names;
add a comment briefly describing what the device does]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw/gpio/gpio_key.c')
-rw-r--r-- | hw/gpio/gpio_key.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/hw/gpio/gpio_key.c b/hw/gpio/gpio_key.c new file mode 100644 index 0000000000..ef287727b6 --- /dev/null +++ b/hw/gpio/gpio_key.c @@ -0,0 +1,104 @@ +/* + * GPIO key + * + * Copyright (c) 2016 Linaro Limited + * + * Author: Shannon Zhao <shannon.zhao@linaro.org> + * + * Emulate a (human) keypress -- when the key is triggered by + * setting the incoming gpio line, the outbound irq line is + * raised for 100ms before being dropped again. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "hw/sysbus.h" + +#define TYPE_GPIOKEY "gpio-key" +#define GPIOKEY(obj) OBJECT_CHECK(GPIOKEYState, (obj), TYPE_GPIOKEY) +#define GPIO_KEY_LATENCY 100 /* 100ms */ + +typedef struct GPIOKEYState { + SysBusDevice parent_obj; + + QEMUTimer *timer; + qemu_irq irq; +} GPIOKEYState; + +static const VMStateDescription vmstate_gpio_key = { + .name = "gpio-key", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_TIMER_PTR(timer, GPIOKEYState), + VMSTATE_END_OF_LIST() + } +}; + +static void gpio_key_reset(DeviceState *dev) +{ + GPIOKEYState *s = GPIOKEY(dev); + + timer_del(s->timer); +} + +static void gpio_key_timer_expired(void *opaque) +{ + GPIOKEYState *s = (GPIOKEYState *)opaque; + + qemu_set_irq(s->irq, 0); + timer_del(s->timer); +} + +static void gpio_key_set_irq(void *opaque, int irq, int level) +{ + GPIOKEYState *s = (GPIOKEYState *)opaque; + + qemu_set_irq(s->irq, 1); + timer_mod(s->timer, + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + GPIO_KEY_LATENCY); +} + +static void gpio_key_realize(DeviceState *dev, Error **errp) +{ + GPIOKEYState *s = GPIOKEY(dev); + SysBusDevice *sbd = SYS_BUS_DEVICE(dev); + + sysbus_init_irq(sbd, &s->irq); + qdev_init_gpio_in(dev, gpio_key_set_irq, 1); + s->timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, gpio_key_timer_expired, s); +} + +static void gpio_key_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = gpio_key_realize; + dc->vmsd = &vmstate_gpio_key; + dc->reset = &gpio_key_reset; +} + +static const TypeInfo gpio_key_info = { + .name = TYPE_GPIOKEY, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(GPIOKEYState), + .class_init = gpio_key_class_init, +}; + +static void gpio_key_register_types(void) +{ + type_register_static(&gpio_key_info); +} + +type_init(gpio_key_register_types) |