PersistentGPIO.hxx

 
#ifndef _OS_PERSISTENTGPIO_HXX_
#define _OS_PERSISTENTGPIO_HXX_
 
#include "utils/StoredBitSet.hxx"
#include "os/Gpio.hxx"
 
extern StoredBitSet *g_gpio_stored_bit_set;
 
class PersistentGpio : public Gpio
{
public:
    constexpr PersistentGpio(const Gpio *impl, const unsigned bit_ofs)
        : impl_(impl)
        , bit_(bit_ofs)
    {
    }
 
    void restore() const {
        impl_->write(g_gpio_stored_bit_set->get_bit(bit_));
    }
    
    void write(Value new_state) const OVERRIDE
    {
        impl_->write(new_state);
        g_gpio_stored_bit_set->set_bit(bit_, new_state).lock_and_flush();
    }
 
    void set() const OVERRIDE
    {
        impl_->set();
        g_gpio_stored_bit_set->set_bit(bit_, true).lock_and_flush();
    }
 
    void clr() const OVERRIDE
    {
        impl_->clr();
        g_gpio_stored_bit_set->set_bit(bit_, false).lock_and_flush();
    }
 
    Value read() const OVERRIDE
    {
        return impl_->read();
    }
 
    void set_direction(Direction dir) const OVERRIDE
    {
        // NOTE: not sure if it's a good idea to let the direction be modified,
        // since upon boot we will restore something else. We don't persist the
        // direction.
        return impl_->set_direction(dir);
    }
 
    Direction direction() const OVERRIDE
    {
        return impl_->direction();
    }
 
private:
    const Gpio *impl_;
    const unsigned bit_;
};
 
#endif // _OS_PERSISTENTGPIO_HXX_