Marek Vasut [mailto:ma...@denx.de] > Sent: Wednesday, June 10, 2020 9:21 PM [...] > >>>>> + /* ADC Bias Calibration: > >>>>> + * read efuse offset 0x7d to get a 17-bit data. Remove the > >> dummy/fake > >>>>> + * bit (bit3) to rebuild the real 16-bit data. Write the data > >>>>> to the > >>>>> + * ADC ioffset. > >>>>> + */ > >>>>> + ocp_data = r8152_efuse_read(tp, 0x7d); > >>>>> + data = (u16)(((ocp_data & 0x1fff0) >> 1) | (ocp_data & 0x7)); > >>>> > >>>> Are these type casts really needed ? > >>> > >>> Is there not a warning from u32 to u16? > >> > >> There is, but it seems justified to warn about conversion from u32 to > >> u16, so maybe that needs to be fixed ? > > > > Excuse me. I don't understand what you mean. > > The original is 17-bit data, so I use u32 to store it. And, > > the final desired data is 16-bit. That is why > > I have to convert it from u32 to u16. > > So what happens to that bit 17 , is it dropped ?
I have descripted is in the code, such as following. /* ADC Bias Calibration: * read efuse offset 0x7d to get a 17-bit data. Remove the dummy/fake * bit (bit3) to rebuild the real 16-bit data. Write the data to the * ADC ioffset. */ The real data (16-bit) would be inserted a dummy bit, and store the 17-bit to efuse offset 0x7d. Therefore, when reading the 17-bit data from efuse, we have to remove the dummy to get the real data. Best Regards, Hayes