I was looking at the code from driverlib that TI delivers for his MSP430 devices and some surprise and questions arose to me. To make the point clear let’s take the init function for the ADC(the same applies to other init functions). Here the declaration in the .h file

/*****************************************************************************
//
//! brief Initializes the ADC12B Module.
//!
//! This function initializes the ADC module to allow for analog-to-digital
//! conversions. Specifically this function sets up the sample-and-hold signal
//! and clock sources for the ADC core to use for conversions. Upon successful
//! completion of the initialization all of the ADC control registers will be
//! reset, excluding the memory controls and reference module bits, the given
//! parameters will be set, and the ADC core will be turned on (Note, that the
//! ADC core only draws power during conversions and remains off when not
//! converting).Note that sample/hold signal sources are device dependent. Note
//! that if re-initializing the ADC after starting a conversion with the
//! startConversion() function, the disableConversion() must be called BEFORE
//! this function can be called.
//!
//! param baseAddress is the base address of the ADC12B module.
//! param param is the pointer to struct for initialization.
//!
//! return STATUS_SUCCESS or STATUS_FAILURE of the initialization process.
//
//*****************************************************************************
extern bool ADC12_B_init(uint16_t baseAddress,
                         ADC12_B_initParam *param);

and here the related code

bool ADC12_B_init(uint16_t baseAddress, ADC12_B_initParam *param)
{
    //Make sure the ENC bit is cleared before initializing the ADC12
    HWREG8(baseAddress + OFS_ADC12CTL0_L) &= ~ADC12ENC;

    bool retVal = STATUS_SUCCESS;

    //Turn OFF ADC12B Module & Clear Interrupt Registers
    HWREG16(baseAddress + OFS_ADC12CTL0) &= ~(ADC12ON + ADC12ENC + ADC12SC);
    HWREG16(baseAddress + OFS_ADC12IER0)  &= 0x0000; //Reset ALL interrupt enables
    HWREG16(baseAddress + OFS_ADC12IER1)  &= 0x0000;
    HWREG16(baseAddress + OFS_ADC12IER2)  &= 0x0000;
    HWREG16(baseAddress + OFS_ADC12IFGR0)  &= 0x0000; //Reset ALL interrupt flags
    HWREG16(baseAddress + OFS_ADC12IFGR1)  &= 0x0000;
    HWREG16(baseAddress + OFS_ADC12IFGR2)  &= 0x0000;

    //Set ADC12B Control 1
    HWREG16(baseAddress + OFS_ADC12CTL1) =
        param->sampleHoldSignalSourceSelect //Setup the Sample-and-Hold Source
        + (param->clockSourceDivider & ADC12DIV_7) //Set Clock Divider
        + (param->clockSourcePredivider & ADC12PDIV__64)
        + param->clockSourceSelect; //Setup Clock Source

    //Set ADC12B Control 2
    HWREG16(baseAddress + OFS_ADC12CTL2) =
        ADC12RES_2; //Default resolution to 12-bits

    //Set ADC12B Control 3
    HWREG16(baseAddress + OFS_ADC12CTL3) =
        param->internalChannelMap; // Map internal channels

    return (retVal) ;
}

From the documentation one expects that some kind of checking is done in the function to assert if the initialization were fine or not, but looking at the code there is no checking at all: retVal is initialized to STATUS_SUCCESS and returned as is.

So what’s for defining a init function as bool? Is this bad code?something incomplete?something I am missing?

After all I was also wondering what checks can you make on init functions?Maybe some precondition tests on the init param?Another thing that came to my mind is to check if the input pin have been configured correctly, so in this case to check if the pin has been configured an an analog input(the same apply for i2c, spi,…). The drawback of this is that may the library becomes too tight to the specific device and less portable.