diff options
Diffstat (limited to 'Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32')
-rw-r--r-- | Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32 | 29 |
1 files changed, 17 insertions, 12 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32 index ad2cc63e4bf8..73498ff666bd 100644 --- a/Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32 +++ b/Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32 @@ -17,9 +17,11 @@ KernelVersion: 4.13 Contact: fabrice.gasnier@st.com Description: Configure the device counter quadrature modes: + - non-quadrature: Encoder IN1 input servers as the count input (up direction). + - quadrature: Encoder IN1 and IN2 inputs are mixed to get direction and count. @@ -35,23 +37,26 @@ KernelVersion: 4.13 Contact: fabrice.gasnier@st.com Description: Configure the device encoder/counter active edge: + - rising-edge - falling-edge - both-edges In non-quadrature mode, device counts up on active edge. + In quadrature mode, encoder counting scenarios are as follows: - ---------------------------------------------------------------- + + +---------+----------+--------------------+--------------------+ | Active | Level on | IN1 signal | IN2 signal | - | edge | opposite |------------------------------------------ + | edge | opposite +----------+---------+----------+---------+ | | signal | Rising | Falling | Rising | Falling | - ---------------------------------------------------------------- - | Rising | High -> | Down | - | Up | - | - | edge | Low -> | Up | - | Down | - | - ---------------------------------------------------------------- - | Falling | High -> | - | Up | - | Down | - | edge | Low -> | - | Down | - | Up | - ---------------------------------------------------------------- - | Both | High -> | Down | Up | Up | Down | - | edges | Low -> | Up | Down | Down | Up | - ---------------------------------------------------------------- + +---------+----------+----------+---------+----------+---------+ + | Rising | High -> | Down | - | Up | - | + | edge | Low -> | Up | - | Down | - | + +---------+----------+----------+---------+----------+---------+ + | Falling | High -> | - | Up | - | Down | + | edge | Low -> | - | Down | - | Up | + +---------+----------+----------+---------+----------+---------+ + | Both | High -> | Down | Up | Up | Down | + | edges | Low -> | Up | Down | Down | Up | + +---------+----------+----------+---------+----------+---------+ |