Constant imxrt_ral::ccm::CDHIPR::PERIPH_CLK_SEL_BUSY::RW::PERIPH_CLK_SEL_BUSY_1

pub const PERIPH_CLK_SEL_BUSY_1: u32 = 0x01;

mux is busy with handshake process with module. The value read in the periph_clk_sel represents the previous value of select, and after the handshake periph_clk_sel value will be applied.