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1==============================
2Cirrus Logic EP93xx ADC driver
3==============================
4
51. Overview
6===========
7
8The driver is intended to work on both low-end (EP9301, EP9302) devices with
95-channel ADC and high-end (EP9307, EP9312, EP9315) devices with 10-channel
10touchscreen/ADC module.
11
122. Channel numbering
13====================
14
15Numbering scheme for channels 0..4 is defined in EP9301 and EP9302 datasheets.
16EP9307, EP9312 and EP9315 have 3 channels more (total 8), but the numbering is
17not defined. So the last three are numbered randomly, let's say.
18
19Assuming ep93xx_adc is IIO device0, you'd find the following entries under
20/sys/bus/iio/devices/iio:device0/:
21
22 +-----------------+---------------+
23 | sysfs entry | ball/pin name |
24 +=================+===============+
25 | in_voltage0_raw | YM |
26 +-----------------+---------------+
27 | in_voltage1_raw | SXP |
28 +-----------------+---------------+
29 | in_voltage2_raw | SXM |
30 +-----------------+---------------+
31 | in_voltage3_raw | SYP |
32 +-----------------+---------------+
33 | in_voltage4_raw | SYM |
34 +-----------------+---------------+
35 | in_voltage5_raw | XP |
36 +-----------------+---------------+
37 | in_voltage6_raw | XM |
38 +-----------------+---------------+
39 | in_voltage7_raw | YP |
40 +-----------------+---------------+