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Diffstat (limited to 'Documentation/ABI/testing/sysfs-bus-iio-timer-stm32')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 new file mode 100644 index 000000000000..161c147d3c40 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 @@ -0,0 +1,155 @@ +What: /sys/bus/iio/devices/triggerX/master_mode_available +KernelVersion: 4.11 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the list possible master modes which are: + - "reset" : The UG bit from the TIMx_EGR register is + used as trigger output (TRGO). + - "enable" : The Counter Enable signal CNT_EN is used + as trigger output. + - "update" : The update event is selected as trigger output. + For instance a master timer can then be used + as a prescaler for a slave timer. + - "compare_pulse" : The trigger output send a positive pulse + when the CC1IF flag is to be set. + - "OC1REF" : OC1REF signal is used as trigger output. + - "OC2REF" : OC2REF signal is used as trigger output. + - "OC3REF" : OC3REF signal is used as trigger output. + - "OC4REF" : OC4REF signal is used as trigger output. + Additional modes (on TRGO2 only): + - "OC5REF" : OC5REF signal is used as trigger output. + - "OC6REF" : OC6REF signal is used as trigger output. + - "compare_pulse_OC4REF": + OC4REF rising or falling edges generate pulses. + - "compare_pulse_OC6REF": + OC6REF rising or falling edges generate pulses. + - "compare_pulse_OC4REF_r_or_OC6REF_r": + OC4REF or OC6REF rising edges generate pulses. + - "compare_pulse_OC4REF_r_or_OC6REF_f": + OC4REF rising or OC6REF falling edges generate pulses. + - "compare_pulse_OC5REF_r_or_OC6REF_r": + OC5REF or OC6REF rising edges generate pulses. + - "compare_pulse_OC5REF_r_or_OC6REF_f": + OC5REF rising or OC6REF falling edges generate pulses. + + +-----------+ +-------------+ +---------+ + | Prescaler +-> | Counter | +-> | Master | TRGO(2) + +-----------+ +--+--------+-+ |-> | Control +--> + | | || +---------+ + +--v--------+-+ OCxREF || +---------+ + | Chx compare +----------> | Output | ChX + +-----------+-+ | | Control +--> + . | | +---------+ + . | | . + +-----------v-+ OC6REF | . + | Ch6 compare +---------+> + +-------------+ + + Example with: "compare_pulse_OC4REF_r_or_OC6REF_r": + + X + X X + X . . X + X . . X + X . . X + count X . . . . X + . . . . + . . . . + +---------------+ + OC4REF | . . | + +-+ . . +-+ + . +---+ . + OC6REF . | | . + +-------+ +-------+ + +-+ +-+ + TRGO2 | | | | + +-+ +---+ +---------+ + +What: /sys/bus/iio/devices/triggerX/master_mode +KernelVersion: 4.11 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the current master modes. + Writing set the master mode + +What: /sys/bus/iio/devices/triggerX/sampling_frequency +KernelVersion: 4.11 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the current sampling frequency. + Writing an value different of 0 set and start sampling. + Writing 0 stop sampling. + +What: /sys/bus/iio/devices/iio:deviceX/in_count0_preset +KernelVersion: 4.12 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the current preset value. + Writing sets the preset value. + When counting up the counter starts from 0 and fires an + event when reach preset value. + When counting down the counter start from preset value + and fire event when reach 0. + +What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available +KernelVersion: 4.12 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the list possible quadrature modes. + +What: /sys/bus/iio/devices/iio:deviceX/in_count0_quadrature_mode +KernelVersion: 4.12 +Contact: benjamin.gaignard@st.com +Description: + Configure the device counter quadrature modes: + channel_A: + Encoder A input servers as the count input and B as + the UP/DOWN direction control input. + + channel_B: + Encoder B input serves as the count input and A as + the UP/DOWN direction control input. + + quadrature: + Encoder A and B inputs are mixed to get direction + and count with a scale of 0.25. + +What: /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available +KernelVersion: 4.12 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the list possible enable modes. + +What: /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode +KernelVersion: 4.12 +Contact: benjamin.gaignard@st.com +Description: + Configure the device counter enable modes, in all case + counting direction is set by in_count0_count_direction + attribute and the counter is clocked by the internal clock. + always: + Counter is always ON. + + gated: + Counting is enabled when connected trigger signal + level is high else counting is disabled. + + triggered: + Counting is enabled on rising edge of the connected + trigger, and remains enabled for the duration of this + selected mode. + +What: /sys/bus/iio/devices/iio:deviceX/in_count_trigger_mode_available +KernelVersion: 4.13 +Contact: benjamin.gaignard@st.com +Description: + Reading returns the list possible trigger modes. + +What: /sys/bus/iio/devices/iio:deviceX/in_count0_trigger_mode +KernelVersion: 4.13 +Contact: benjamin.gaignard@st.com +Description: + Configure the device counter trigger mode + counting direction is set by in_count0_count_direction + attribute and the counter is clocked by the connected trigger + rising edges. |