1What:		/sys/bus/iio/devices/iio:deviceX/in_voltage_spi_clk_freq
2KernelVersion:	4.14
3Contact:	arnaud.pouliquen@st.com
4Description:
5		For audio purpose only.
6		Used by audio driver to set/get the spi input frequency.
7		This is mandatory if DFSDM is slave on SPI bus, to
8		provide information on the SPI clock frequency during runtime
9		Notice that the SPI frequency should be a multiple of sample
10		frequency to ensure the precision.
11		if DFSDM input is SPI master
12			Reading  SPI clkout frequency,
13			error on writing
14		If DFSDM input is SPI Slave:
15			Reading returns value previously set.
16			Writing value before starting conversions.