/*************** primitives for use in any context *********************/
static inline uint8_t hp_sdc_status_in8 (void) {
uint8_t status;
unsigned long flags;
write_lock_irqsave(&hp_sdc.ibf_lock, flags);
status = sdc_readb(hp_sdc.status_io);
if (!(status & HP_SDC_STATUS_IBF)) hp_sdc.ibf = 0;
write_unlock_irqrestore(&hp_sdc.ibf_lock, flags);
return status;
}
/* Care must be taken to only invoke hp_sdc_spin_ibf when
* absolutely needed, or in rarely invoked subroutines.
* Not only does it waste CPU cycles, it also wastes bus cycles.
*/
static inline void hp_sdc_spin_ibf(void) {
unsigned long flags;
rwlock_t *lock;
lock = &hp_sdc.ibf_lock;
read_lock_irqsave(lock, flags);
if (!hp_sdc.ibf) {
read_unlock_irqrestore(lock, flags);
return;
}
read_unlock(lock);
write_lock(lock);
while (sdc_readb(hp_sdc.status_io) & HP_SDC_STATUS_IBF) {};
hp_sdc.ibf = 0;
write_unlock_irqrestore(lock, flags);
}
static inline uint8_t hp_sdc_data_in8(void)
{
return sdc_readb(hp_sdc.data_io);
}