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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+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.