[PATCH v14 1/3] HID: quirks: Allow inverting the absolute X/Y values

From: Alistair Francis
Date: Wed Nov 03 2021 - 07:38:16 EST


Add a HID_QUIRK_X_INVERT/HID_QUIRK_Y_INVERT quirk that can be used
to invert the X/Y values.

Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx>
---
drivers/hid/hid-input.c | 6 ++++++
include/linux/hid.h | 2 ++
2 files changed, 8 insertions(+)

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 4b5ebeacd283..173fcd3d92df 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -1328,6 +1328,12 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct

input = field->hidinput->input;

+ if (usage->type == EV_ABS &&
+ (((*quirks & HID_QUIRK_X_INVERT) && usage->code == ABS_X) ||
+ ((*quirks & HID_QUIRK_Y_INVERT) && usage->code == ABS_Y))) {
+ value = field->logical_maximum - value;
+ }
+
if (usage->hat_min < usage->hat_max || usage->hat_dir) {
int hat_dir = usage->hat_dir;
if (!hat_dir)
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 9e067f937dbc..4959385ca588 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -349,6 +349,8 @@ struct hid_item {
/* BIT(9) reserved for backward compatibility, was NO_INIT_INPUT_REPORTS */
#define HID_QUIRK_ALWAYS_POLL BIT(10)
#define HID_QUIRK_INPUT_PER_APP BIT(11)
+#define HID_QUIRK_X_INVERT BIT(12)
+#define HID_QUIRK_Y_INVERT BIT(13)
#define HID_QUIRK_SKIP_OUTPUT_REPORTS BIT(16)
#define HID_QUIRK_SKIP_OUTPUT_REPORT_ID BIT(17)
#define HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP BIT(18)
--
2.31.1