Some Quadrature Encoders can swap phase inputs A and B internally. This
new function will allow drivers to configure input swap mode.
This was implemented by Felipe Balbi while he was working at Intel.
Signed-off-by: Felipe Balbi (Intel) <balbi@xxxxxxxxxx>
Signed-off-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-bus-counter | 4 ++++
drivers/counter/counter.c | 3 ++-
include/linux/counter.h | 3 ++-
3 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-counter b/Documentation/ABI/testing/sysfs-bus-counter
index 566bd99fe0a5..8f1e3de88c77 100644
--- a/Documentation/ABI/testing/sysfs-bus-counter
+++ b/Documentation/ABI/testing/sysfs-bus-counter
@@ -146,6 +146,10 @@ Description:
updates the respective count. Quadrature encoding
determines the direction.
+ quadrature x4 swapped:
+ Same as quadrature x4, however Phase A and Phase B
+ signals are swapped.
+
What: /sys/bus/counter/devices/counterX/countY/name
KernelVersion: 5.2
Contact: linux-iio@xxxxxxxxxxxxxxx
diff --git a/drivers/counter/counter.c b/drivers/counter/counter.c
index 6a683d086008..11d357245b14 100644
--- a/drivers/counter/counter.c
+++ b/drivers/counter/counter.c
@@ -752,7 +752,8 @@ static const char *const counter_count_function_str[] = {
[COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B] = "quadrature x1 b",
[COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A] = "quadrature x2 a",
[COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B] = "quadrature x2 b",
- [COUNTER_COUNT_FUNCTION_QUADRATURE_X4] = "quadrature x4"
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X4] = "quadrature x4",
+ [COUNTER_COUNT_FUNCTION_QUADRATURE_X4_SWAPPED] = "quadrature x4 swapped"
};
static ssize_t counter_function_show(struct device *dev,
diff --git a/include/linux/counter.h b/include/linux/counter.h
index 9dbd5df4cd34..c3b4d263eb22 100644
--- a/include/linux/counter.h
+++ b/include/linux/counter.h
@@ -170,7 +170,8 @@ enum counter_count_function {
COUNTER_COUNT_FUNCTION_QUADRATURE_X1_B,
COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,
- COUNTER_COUNT_FUNCTION_QUADRATURE_X4
+ COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
+ COUNTER_COUNT_FUNCTION_QUADRATURE_X4_SWAPPED,
};
/**
--
2.30.2
