Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32

   1 What:           /sys/bus/iio/devices/iio:deviceX/in_count0_preset
   2 KernelVersion:  4.13
   3 Contact:        fabrice.gasnier@st.com
   4 Description:
   5                 Reading returns the current preset value. Writing sets the
   6                 preset value. Encoder counts continuously from 0 to preset
   7                 value, depending on direction (up/down).
   8
   9 What:           /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
  10 KernelVersion:  4.13
  11 Contact:        fabrice.gasnier@st.com
  12 Description:
  13                 Reading returns the list possible quadrature modes.
  14
  15 What:           /sys/bus/iio/devices/iio:deviceX/in_count0_quadrature_mode
  16 KernelVersion:  4.13
  17 Contact:        fabrice.gasnier@st.com
  18 Description:
  19                 Configure the device counter quadrature modes:
  20                 - non-quadrature:
  21                         Encoder IN1 input servers as the count input (up
  22                         direction).
  23                 - quadrature:
  24                         Encoder IN1 and IN2 inputs are mixed to get direction
  25                         and count.
  26
  27 What:           /sys/bus/iio/devices/iio:deviceX/in_count_polarity_available
  28 KernelVersion:  4.13
  29 Contact:        fabrice.gasnier@st.com
  30 Description:
  31                 Reading returns the list possible active edges.
  32
  33 What:           /sys/bus/iio/devices/iio:deviceX/in_count0_polarity
  34 KernelVersion:  4.13
  35 Contact:        fabrice.gasnier@st.com
  36 Description:
  37                 Configure the device encoder/counter active edge:
  38                 - rising-edge
  39                 - falling-edge
  40                 - both-edges
  41
  42                 In non-quadrature mode, device counts up on active edge.
  43                 In quadrature mode, encoder counting scenarios are as follows:
  44                 ----------------------------------------------------------------
  45                 | Active  | Level on |      IN1 signal    |     IN2 signal     |
  46                 | edge    | opposite |------------------------------------------
  47                 |         | signal   |  Rising  | Falling |  Rising  | Falling |
  48                 ----------------------------------------------------------------
  49                 | Rising  | High ->  |   Down   |    -    |    Up    |    -    |
  50                 | edge    | Low  ->  |    Up    |    -    |   Down   |    -    |
  51                 ----------------------------------------------------------------
  52                 | Falling | High ->  |    -     |    Up   |    -     |   Down  |
  53                 | edge    | Low  ->  |    -     |   Down  |    -     |    Up   |
  54                 ----------------------------------------------------------------
  55                 | Both    | High ->  |   Down   |    Up   |    Up    |   Down  |
  56                 | edges   | Low  ->  |    Up    |   Down  |   Down   |    Up   |
  57                 ----------------------------------------------------------------