The first line should be readable enough, but in case it's longer than that, I way prefer the style of

  setup_spi(&adc, mode=SPI_01, rate=15, cs_control=CS_MUXED,  
            cs=0x01);
  setup_spi(&eeprom, mode=SPI_10, rate=13, cs_control=CS_MUXED,  
            cs=0x02);
  setup_spi(&mram, mode=SPI_10, rate=50, cs_control=CS_DIRECT, 
            cs=0x08);

I like short lines in general, as having a bunch of short lines (which tend to be the norm in code) and suddenly a very long line is terrible for readability. But all has exemptions. It's also very dependent on the programming language.