summaryrefslogtreecommitdiffstats
path: root/Documentation/iio/ep93xx_adc.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/iio/ep93xx_adc.rst')
-rw-r--r--Documentation/iio/ep93xx_adc.rst40
1 files changed, 40 insertions, 0 deletions
diff --git a/Documentation/iio/ep93xx_adc.rst b/Documentation/iio/ep93xx_adc.rst
new file mode 100644
index 0000000000..0af0e90404
--- /dev/null
+++ b/Documentation/iio/ep93xx_adc.rst
@@ -0,0 +1,40 @@
+==============================
+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 |
+ +-----------------+---------------+