Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32

   1 What:           /sys/bus/iio/devices/iio:deviceX/in_voltage_spi_clk_freq
   2 KernelVersion:  4.14
   3 Contact:        arnaud.pouliquen@st.com
   4 Description:
   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.