From 6ed1de089c35ab283924c2fec96794909fc0df85 Mon Sep 17 00:00:00 2001
From: Kuratius <[EMAIL REDACTED]>
Date: Tue, 19 May 2026 15:34:02 +0200
Subject: [PATCH] Fix touchpad finger detection on Steam Deck
---
src/joystick/hidapi/SDL_hidapi_steamdeck.c | 47 +++++++++++++++++-----
1 file changed, 36 insertions(+), 11 deletions(-)
diff --git a/src/joystick/hidapi/SDL_hidapi_steamdeck.c b/src/joystick/hidapi/SDL_hidapi_steamdeck.c
index 286b7c97ea8dc..d847abb94614d 100644
--- a/src/joystick/hidapi/SDL_hidapi_steamdeck.c
+++ b/src/joystick/hidapi/SDL_hidapi_steamdeck.c
@@ -65,6 +65,8 @@ typedef enum
STEAMDECK_LBUTTON_R5 = 0x00010000,
STEAMDECK_LBUTTON_LEFT_PAD = 0x00020000,
STEAMDECK_LBUTTON_RIGHT_PAD = 0x00040000,
+ STEAMDECK_LBUTTON_LEFT_TOUCHPAD_TOUCH = 0x00080000,
+ STEAMDECK_LBUTTON_RIGHT_TOUCHPAD_TOUCH = 0x00100000,
STEAMDECK_LBUTTON_L3 = 0x00400000,
STEAMDECK_LBUTTON_R3 = 0x04000000,
@@ -81,6 +83,13 @@ typedef struct
Uint64 sensor_timestamp_ns;
Uint64 last_button_state;
Uint8 watchdog_counter;
+
+ bool left_touch_down;
+ float left_touch_x;
+ float left_touch_y;
+ bool right_touch_down;
+ float right_touch_x;
+ float right_touch_y;
} SDL_DriverSteamDeck_Context;
static bool DisableDeckLizardMode(SDL_hid_device *dev)
@@ -248,17 +257,33 @@ static void HIDAPI_DriverSteamDeck_HandleState(SDL_HIDAPI_Device *device,
values[2] = (-pInReport->payload.deckState.sAccelY / 32768.0f) * 2.0f * SDL_STANDARD_GRAVITY;
SDL_SendJoystickSensor(timestamp, joystick, SDL_SENSOR_ACCEL, ctx->sensor_timestamp_ns, values, 3);
- SDL_SendJoystickTouchpad(timestamp, joystick, 0, 0,
- pInReport->payload.deckState.sPressurePadLeft > 0,
- pInReport->payload.deckState.sLeftPadX / 65536.0f + 0.5f,
- pInReport->payload.deckState.sLeftPadY / 65536.0f + 0.5f,
- pInReport->payload.deckState.sPressurePadLeft / 32768.0f);
-
- SDL_SendJoystickTouchpad(timestamp, joystick, 1, 0,
- pInReport->payload.deckState.sPressurePadRight > 0,
- pInReport->payload.deckState.sRightPadX / 65536.0f + 0.5f,
- pInReport->payload.deckState.sRightPadY / 65536.0f + 0.5f,
- pInReport->payload.deckState.sPressurePadRight / 32768.0f);
+ bool left_touch_down = (pInReport->payload.deckState.ulButtonsL & STEAMDECK_LBUTTON_LEFT_TOUCHPAD_TOUCH) ? true : false;
+ bool right_touch_down = (pInReport->payload.deckState.ulButtonsL & STEAMDECK_LBUTTON_RIGHT_TOUCHPAD_TOUCH) ? true : false;
+ if (left_touch_down || ctx->left_touch_down) {
+ if (left_touch_down) {
+ ctx->left_touch_x = pInReport->payload.deckState.sLeftPadX / 65536.0f + 0.5f;
+ ctx->left_touch_y = -(float)pInReport->payload.deckState.sLeftPadY / 65536.0f + 0.5f;
+
+ }
+ SDL_SendJoystickTouchpad(timestamp, joystick, 0, 0,
+ left_touch_down,
+ ctx->left_touch_x,
+ ctx->left_touch_y,
+ pInReport->payload.deckState.sPressurePadLeft / 32768.0f);
+ ctx->left_touch_down = left_touch_down;
+ }
+ if (right_touch_down || ctx->right_touch_down) {
+ if (right_touch_down) {
+ ctx->right_touch_x = pInReport->payload.deckState.sRightPadX / 65536.0f + 0.5f;
+ ctx->right_touch_y = -(float)pInReport->payload.deckState.sRightPadY / 65536.0f + 0.5f;
+ }
+ SDL_SendJoystickTouchpad(timestamp, joystick, 1, 0,
+ right_touch_down,
+ ctx->right_touch_x,
+ ctx->right_touch_y,
+ pInReport->payload.deckState.sPressurePadRight / 32768.0f);
+ ctx->right_touch_down = right_touch_down;
+ }
}
/*****************************************************************************************************/