genode/repos/os/include/gpio/component.h
Norman Feske 4d442bca30 Streamline exception types
This patch reduces the number of exception types by facilitating
globally defined exceptions for common usage patterns shared by most
services. In particular, RPC functions that demand a session-resource
upgrade not longer reflect this condition via a session-specific
exception but via the 'Out_of_ram' or 'Out_of_caps' types.

Furthermore, the 'Parent::Service_denied', 'Parent::Unavailable',
'Root::Invalid_args', 'Root::Unavailable', 'Service::Invalid_args',
'Service::Unavailable', and 'Local_service::Factory::Denied' types have
been replaced by the single 'Service_denied' exception type defined in
'session/session.h'.

This consolidation eases the error handling (there are fewer exceptions
to handle), alleviates the need to convert exceptions along the
session-creation call chain, and avoids possible aliasing problems
(catching the wrong type with the same name but living in a different
scope).
2017-05-31 13:16:07 +02:00

152 lines
3.7 KiB
C++

/*
* \brief GPIO-session component
* \author Stefan Kalkowski
* \date 2013-05-03
*/
/*
* Copyright (C) 2011-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#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:
struct Irq_session_component : public Genode::Rpc_object<Genode::Irq_session>
{
Driver &_driver;
unsigned long _pin;
Irq_session_component(Driver &driver, unsigned long pin)
: _driver(driver), _pin(pin) { }
/***************************
** Irq_session interface **
***************************/
void ack_irq() override { _driver.ack_irq(_pin); }
void sigh(Genode::Signal_context_capability sigh) override {
_driver.register_signal(_pin, sigh); }
Info info() override {
return { .type = Genode::Irq_session::Info::Type::INVALID }; }
};
Genode::Rpc_entrypoint &_ep;
Driver &_driver;
unsigned long _pin;
Irq_session_component _irq_component;
Genode::Irq_session_capability _irq_cap;
public:
Session_component(Genode::Rpc_entrypoint &ep,
Driver &driver,
unsigned long gpio_pin)
: _ep(ep), _driver(driver), _pin(gpio_pin),
_irq_component(_driver, _pin),
_irq_cap(_ep.manage(&_irq_component)) { }
~Session_component() { _ep.dissolve(&_irq_component); }
/*****************************
** 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 debouncing(unsigned int us)
{
if (us) {
_driver.debounce_time(_pin, us);
_driver.debounce_enable(_pin, true);
} else
_driver.debounce_enable(_pin, false);
}
Genode::Irq_session_capability irq_session(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);
};
_driver.irq_enable(_pin, true);
return _irq_cap;
}
};
class Gpio::Root : public Genode::Root_component<Gpio::Session_component>
{
private:
Genode::Rpc_entrypoint &_ep;
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 Genode::Service_denied();
if (ram_quota < sizeof(Session_component)) {
Genode::warning("insufficient dontated ram_quota "
"(", ram_quota, " bytes), "
"require ", sizeof(Session_component), " bytes");
throw Genode::Insufficient_ram_quota();
}
return new (md_alloc()) Session_component(_ep, _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),
_ep(*session_ep), _driver(driver) { }
};
#endif /* _INCLUDE__GPIO__COMPONENT_H_ */