adc_configure_trigger bug

[avsteele]

in adc.c

the library code:

/**
 * \brief Configure conversion trigger and free run mode.
 *
 * \param p_adc Pointer to an ADC instance.
 * \param trigger Conversion trigger.
 * \param uc_freerun ADC_MR_FREERUN_ON enables freerun mode,
 * ADC_MR_FREERUN_OFF disables freerun mode.
 *
 */
void adc_configure_trigger(Adc *p_adc, const enum adc_trigger_t trigger,
		uint8_t uc_freerun)
{
	//Warning ADC_MR_TRGSEL_Msk does not include ADC_MR_TRGEN.
	p_adc->ADC_MR &= ~(ADC_MR_TRGEN | ADC_MR_TRGSEL_Msk | ADC_MR_FREERUN); //Clear all bits related to triggers and freerun
	
	//Configure FreeRun
	if(uc_freerun & ADC_MR_FREERUN == ADC_MR_FREERUN_ON) {                 //FreeRun is enabled
		p_adc->ADC_MR |= ADC_MR_FREERUN_ON;
		
		//Free Run Mode: Never wait for any trigger
		//No need to continue and enable hardware triggers
		return;
	}
	
	//Configure hardware triggers
	if(trigger & ADC_MR_TRGEN == ADC_MR_TRGEN_EN) {                       //Hardware trigger is enabled
		p_adc->ADC_MR |= (trigger & ADC_MR_TRGSEL_Msk) | ADC_MR_TRGEN_EN; //Set trigger selection bits and enable hardware trigger
	}
}

...will not enable frerrun if passed ADC_ML_FREERUN_ON (0x1u<<7). Because == has higher precedence than & The function will enable freerun only when passed 1. It will not enable freerun when passed ADC_MR_FREERUN_ON .

The corrected line can simply be

if(uc_freerun == ADC_MR_FREERUN_ON) ...

Which is probably the desired behavior according to the documentation, but may break existing usage. Alternatively

if(uc_freerun != ADC_MR_FREERUN_OFF) ...

will enable freerun when passing anything other than ADC_FREERUN_OFF.