From dff487b20a49e50ad18d316dde0fe429f89f87e2 Mon Sep 17 00:00:00 2001
From: Lephe <sebastien.michelland@protonmail.com>
Date: Sun, 30 Mar 2025 16:01:20 +0200
Subject: [PATCH] touch: get calibration info from OS, if known

---
 include/gint/touch.h |  4 ++++
 src/touch/driver.c   |  2 ++
 src/touch/touch.c    | 16 ++++++++++++++++
 3 files changed, 22 insertions(+)

diff --git a/include/gint/touch.h b/include/gint/touch.h
index 0e65638..c761cb7 100644
--- a/include/gint/touch.h
+++ b/include/gint/touch.h
@@ -26,6 +26,10 @@ typedef struct {
 /* touch_calib_get() - get calibration information */
 extern int touch_calib_get(touch_calibration_t *calib);
 
+/* touch_calib_get_os() - get OS calibration information, if available
+   Returns 0 on success, negative number if not available. */
+extern int touch_calib_get_os(touch_calibration_t *calib);
+
 /* touch_calib_set() - set calibration information */
 extern int touch_calib_set(touch_calibration_t *calib);
 
diff --git a/src/touch/driver.c b/src/touch/driver.c
index 078cacd..cdcd535 100644
--- a/src/touch/driver.c
+++ b/src/touch/driver.c
@@ -37,6 +37,8 @@ static void _touch_configure(void)
     __touch_drv_info.calibration.dual_debounce_frame = 0;
     __touch_drv_info.calibration.dual_sensi_entry = 0x18;
     __touch_drv_info.calibration.dual_sensi_leave = 0x24;
+
+    touch_calib_get_os(&__touch_drv_info.calibration);
 }
 
 /* _touch_hsave() - save hardware state */
diff --git a/src/touch/touch.c b/src/touch/touch.c
index f59efcb..dea2779 100644
--- a/src/touch/touch.c
+++ b/src/touch/touch.c
@@ -35,6 +35,22 @@ int touch_calib_get(touch_calibration_t *calib)
     return 0;
 }
 
+int touch_calib_get_os(touch_calibration_t *calib)
+{
+    void *os_version = (void *)0x80020020;
+    if(!memcmp(os_version, "02.01.200", 9) ||
+       !memcmp(os_version, "02.01.700", 9)) {
+        int const *os_calibration = (void *)0x8c1bea50;
+        calib->x_base = os_calibration[0];
+        calib->y_base = os_calibration[1];
+        calib->x_div = os_calibration[2];
+        calib->y_div = os_calibration[3];
+        return 0;
+    }
+
+    return -1;
+}
+
 /* touch_calib_set() - set calibration information */
 int touch_calib_set(touch_calibration_t *calib)
 {