OpenCloudOS-Kernel/Documentation/iio/ep93xx_adc.rst

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Cirrus Logic EP93xx ADC driver
==============================
1. Overview
===========
The driver is intended to work on both low-end (EP9301, EP9302) devices with
5-channel ADC and high-end (EP9307, EP9312, EP9315) devices with 10-channel
touchscreen/ADC module.
2. Channel numbering
====================
Numbering scheme for channels 0..4 is defined in EP9301 and EP9302 datasheets.
EP9307, EP9312 and EP9315 have 3 channels more (total 8), but the numbering is
not defined. So the last three are numbered randomly, let's say.
Assuming ep93xx_adc is IIO device0, you'd find the following entries under
/sys/bus/iio/devices/iio:device0/:
+-----------------+---------------+
| sysfs entry | ball/pin name |
+=================+===============+
| in_voltage0_raw | YM |
+-----------------+---------------+
| in_voltage1_raw | SXP |
+-----------------+---------------+
| in_voltage2_raw | SXM |
+-----------------+---------------+
| in_voltage3_raw | SYP |
+-----------------+---------------+
| in_voltage4_raw | SYM |
+-----------------+---------------+
| in_voltage5_raw | XP |
+-----------------+---------------+
| in_voltage6_raw | XM |
+-----------------+---------------+
| in_voltage7_raw | YP |
+-----------------+---------------+