Compiler/TMS320F280041: Possible bug in F28004x support library for x-bar

Tool/software: TI C/C++ Compiler

I was going through C28x X-BAR driver, more specifically XBAR_setEPWMMuxConfig() function.

Here is the implementation from xbar.c found in F28004x Support Library v1.06.00.00:

//*****************************************************************************
//
// XBAR_setEPWMMuxConfig
//
//*****************************************************************************
void
XBAR_setEPWMMuxConfig(XBAR_TripNum trip, XBAR_EPWMMuxConfig muxConfig)
{
    uint32_t shift;
    uint16_t offset;

    //
    // If the configuration is for MUX16-31, we'll need an odd value to index
    // into the config registers.
    //
    if(((uint32_t)muxConfig & 0x2000U) != 0U)
    {
        offset = ((uint16_t)trip << 1U) + 2U;
    }
    else
    {
        offset = (uint16_t)trip << 1U;
    }

    //
    // Extract the shift from the input value.
    //
    shift = ((uint32_t)muxConfig >> 8U) & 0x7FU;

    //
    // Write the requested muxing value for this XBAR trip.
    //
    EALLOW;

    HWREG(XBAR_EPWM_CFG_REG_BASE + offset) =
        (HWREG(XBAR_EPWM_CFG_REG_BASE + offset) & ~((uint32_t)0x3U << shift)) |
        (((uint32_t)muxConfig & 0x3U) << shift);

    EDIS;
}

Should the "shift" variable in this function be calculated as:

shift = ((uint32_t)muxConfig >> 8U) & 0x0FU;

I may be wrong, but the original mask for shift (0x7FU) won't work for mux 16 to 31. Can someone please check this out?

Thank you!