1What:		/sys/bus/iio/devices/triggerX/trigger_polarity
 2KernelVersion:	4.11
 3Contact:	fabrice.gasnier@st.com
 4Description:
 5		The STM32 ADC can be configured to use external trigger sources
 6		(e.g. timers, pwm or exti gpio). Then, it can be tuned to start
 7		conversions on external trigger by either:
 8		- "rising-edge"
 9		- "falling-edge"
10		- "both-edges".
11		Reading returns current trigger polarity.
12		Writing value before enabling conversions sets trigger polarity.
13
14What:		/sys/bus/iio/devices/triggerX/trigger_polarity_available
15KernelVersion:	4.11
16Contact:	fabrice.gasnier@st.com
17Description:
18		List all available trigger_polarity settings.