[PATCH v12 1/3] HID: quirks: Allow inverting the absolute X/Y values

[Alistair Francis]

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

Signed-off-by: Alistair Francis <alistair at alistair23.me>
---
 drivers/hid/hid-input.c | 7 +++++++
 include/linux/hid.h     | 1 +
 2 files changed, 8 insertions(+)

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 4b5ebeacd283..0a9634473940 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -1328,6 +1328,13 @@ void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct
 
 	input = field->hidinput->input;
 
+	if (*quirks & HID_QUIRK_XY_INVERT) {
+		if (usage->type == EV_ABS &&
+			(usage->code == ABS_X || 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..a6e91ee5b3de 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -349,6 +349,7 @@ 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_XY_INVERT			BIT(12)
 #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