genode/os/include/gpio/component.h
Stefan Kalkowski ca92984bcc Simplify GPIO session interface (fix #707)
Changes GPIO session interface to a one-GPIO-pin-per-session style. Moreover,
this commit introduces a generic driver interface for GPIO drivers. Thereby
generalizes root- and session component for GPIO.
2013-05-10 11:16:12 +02:00

129 lines
2.9 KiB
C++

/*
* \brief GPIO-session component
* \author Stefan Kalkowski
* \date 2013-05-03
*/
/*
* Copyright (C) 2011-2013 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _INCLUDE__GPIO__COMPONENT_H_
#define _INCLUDE__GPIO__COMPONENT_H_
#include <base/printf.h>
#include <root/component.h>
#include <gpio_session/gpio_session.h>
#include <gpio/driver.h>
namespace Gpio {
class Session_component;
class Root;
};
class Gpio::Session_component : public Genode::Rpc_object<Gpio::Session>
{
private:
Driver &_driver;
unsigned long _pin;
Genode::Signal_context_capability _sigh;
public:
Session_component(Driver &driver, unsigned long gpio_pin)
: _driver(driver), _pin(gpio_pin) { }
~Session_component()
{
if (_sigh.valid())
_driver.unregister_signal(_pin);
}
/************************************
** Gpio::Session interface **
************************************/
void direction(Direction d) { _driver.direction(_pin, (d == IN)); }
void write(bool level) { _driver.write(_pin, level); }
bool read() { return _driver.read(_pin); }
void irq_enable(bool enable) { _driver.irq_enable(_pin, enable); }
void irq_sigh(Genode::Signal_context_capability cap)
{
if (cap.valid()) {
_sigh = cap;
_driver.register_signal(_pin, cap);
}
}
void irq_type(Irq_type type)
{
switch (type) {
case HIGH_LEVEL:
_driver.high_detect(_pin);
break;
case LOW_LEVEL:
_driver.low_detect(_pin);
break;
case RISING_EDGE:
_driver.rising_detect(_pin);
break;
case FALLING_EDGE:
_driver.falling_detect(_pin);
};
}
void debouncing(unsigned int us)
{
if (us) {
_driver.debounce_time(_pin, us);
_driver.debounce_enable(_pin, true);
} else
_driver.debounce_enable(_pin, false);
}
};
class Gpio::Root : public Genode::Root_component<Gpio::Session_component>
{
private:
Driver &_driver;
protected:
Session_component *_create_session(const char *args)
{
unsigned long pin =
Genode::Arg_string::find_arg(args, "gpio").ulong_value(0);
Genode::size_t ram_quota =
Genode::Arg_string::find_arg(args, "ram_quota").ulong_value(0);
if (!_driver.gpio_valid(pin))
throw Invalid_args();
if (ram_quota < sizeof(Session_component)) {
PWRN("Insufficient dontated ram_quota (%zd bytes), require %zd bytes",
ram_quota, sizeof(Session_component));
throw Genode::Root::Quota_exceeded();
}
return new (md_alloc()) Session_component(_driver, pin);
}
public:
Root(Genode::Rpc_entrypoint *session_ep,
Genode::Allocator *md_alloc, Driver &driver)
: Genode::Root_component<Gpio::Session_component>(session_ep, md_alloc),
_driver(driver) { }
};
#endif /* _INCLUDE__GPIO__COMPONENT_H_ */