linux_dsm_epyc7002/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32

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iio: Add STM32 timer trigger driver Timers IPs can be used to generate triggers for other IPs like DAC or ADC. Each trigger may result of timer internals signals like counter enable, reset or edge, this configuration could be done through "master_mode" device attribute. Since triggers could be used by DAC or ADC their names are defined in include/ nux/iio/timer/stm32-timer-trigger.h and is_stm32_iio_timer_trigger function could be used to check if the trigger is valid or not. "trgo" trigger have a "sampling_frequency" attribute which allow to configure timer sampling frequency. version 8: - change kernel version from 4.10 to 4.11 in ABI documentation version 7: - remove all iio_device related code - move driver into trigger directory version 5: - simplify tables of triggers - only create an IIO device when needed version 4: - get triggers configuration from "reg" in DT - add tables of triggers - sampling frequency is enable/disable when writing in trigger sampling_frequency attribute - no more use of interruptions version 3: - change compatible to "st,stm32-timer-trigger" - fix attributes access right - use string instead of int for master_mode and slave_mode - document device attributes in sysfs-bus-iio-timer-stm32 version 2: - keep only one compatible - use st,input-triggers-names and st,output-triggers-names to know which triggers are accepted and/or create by the device Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-01-20 16:15:07 +07:00
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.
iio: Add STM32 timer trigger driver Timers IPs can be used to generate triggers for other IPs like DAC or ADC. Each trigger may result of timer internals signals like counter enable, reset or edge, this configuration could be done through "master_mode" device attribute. Since triggers could be used by DAC or ADC their names are defined in include/ nux/iio/timer/stm32-timer-trigger.h and is_stm32_iio_timer_trigger function could be used to check if the trigger is valid or not. "trgo" trigger have a "sampling_frequency" attribute which allow to configure timer sampling frequency. version 8: - change kernel version from 4.10 to 4.11 in ABI documentation version 7: - remove all iio_device related code - move driver into trigger directory version 5: - simplify tables of triggers - only create an IIO device when needed version 4: - get triggers configuration from "reg" in DT - add tables of triggers - sampling frequency is enable/disable when writing in trigger sampling_frequency attribute - no more use of interruptions version 3: - change compatible to "st,stm32-timer-trigger" - fix attributes access right - use string instead of int for master_mode and slave_mode - document device attributes in sysfs-bus-iio-timer-stm32 version 2: - keep only one compatible - use st,input-triggers-names and st,output-triggers-names to know which triggers are accepted and/or create by the device Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-01-20 16:15:07 +07:00
- "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.
iio: Add STM32 timer trigger driver Timers IPs can be used to generate triggers for other IPs like DAC or ADC. Each trigger may result of timer internals signals like counter enable, reset or edge, this configuration could be done through "master_mode" device attribute. Since triggers could be used by DAC or ADC their names are defined in include/ nux/iio/timer/stm32-timer-trigger.h and is_stm32_iio_timer_trigger function could be used to check if the trigger is valid or not. "trgo" trigger have a "sampling_frequency" attribute which allow to configure timer sampling frequency. version 8: - change kernel version from 4.10 to 4.11 in ABI documentation version 7: - remove all iio_device related code - move driver into trigger directory version 5: - simplify tables of triggers - only create an IIO device when needed version 4: - get triggers configuration from "reg" in DT - add tables of triggers - sampling frequency is enable/disable when writing in trigger sampling_frequency attribute - no more use of interruptions version 3: - change compatible to "st,stm32-timer-trigger" - fix attributes access right - use string instead of int for master_mode and slave_mode - document device attributes in sysfs-bus-iio-timer-stm32 version 2: - keep only one compatible - use st,input-triggers-names and st,output-triggers-names to know which triggers are accepted and/or create by the device Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-01-20 16:15:07 +07:00
- "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 | | | |
+-+ +---+ +---------+
iio: Add STM32 timer trigger driver Timers IPs can be used to generate triggers for other IPs like DAC or ADC. Each trigger may result of timer internals signals like counter enable, reset or edge, this configuration could be done through "master_mode" device attribute. Since triggers could be used by DAC or ADC their names are defined in include/ nux/iio/timer/stm32-timer-trigger.h and is_stm32_iio_timer_trigger function could be used to check if the trigger is valid or not. "trgo" trigger have a "sampling_frequency" attribute which allow to configure timer sampling frequency. version 8: - change kernel version from 4.10 to 4.11 in ABI documentation version 7: - remove all iio_device related code - move driver into trigger directory version 5: - simplify tables of triggers - only create an IIO device when needed version 4: - get triggers configuration from "reg" in DT - add tables of triggers - sampling frequency is enable/disable when writing in trigger sampling_frequency attribute - no more use of interruptions version 3: - change compatible to "st,stm32-timer-trigger" - fix attributes access right - use string instead of int for master_mode and slave_mode - document device attributes in sysfs-bus-iio-timer-stm32 version 2: - keep only one compatible - use st,input-triggers-names and st,output-triggers-names to know which triggers are accepted and/or create by the device Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-01-20 16:15:07 +07:00
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.