From a1a31949858bda3ac55c161a17529be2243d82bd Mon Sep 17 00:00:00 2001
From: gudnimg <gudni.m.g@gmail.com>
Date: Sat, 29 Jul 2023 14:24:38 +0000
Subject: [PATCH] tmc2130: Fix wrong values report by M913 when Hold > Run

The firmware will ensure that the Hold current can never
exceed the Run current. In this scenario we must update
the global current array so that M913 reflects the register settings.

Added a echo to serial when this truncation happens

Change in memory:
Flash: +54 bytes
SRAM: 0 bytes
---
 Firmware/tmc2130.cpp | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/Firmware/tmc2130.cpp b/Firmware/tmc2130.cpp
index 10ffb14c6..498b982d3 100755
--- a/Firmware/tmc2130.cpp
+++ b/Firmware/tmc2130.cpp
@@ -520,14 +520,26 @@ static void SetCurrents(const uint8_t axis) {
     uint8_t iHold = currents[axis].iHold;
     const uint8_t iRun = currents[axis].iRun;
 
+    // Make sure iHold never exceeds iRun at runtime
+    if (iHold > iRun) {
+        iHold = iRun;
+
+        // Update global array such that M913 reports correct values
+        currents[axis].iHold = currents[axis].iRun;
+
+        // Let user know firmware modified the value
+        SERIAL_ECHO_START;
+        SERIAL_ECHOLNRPGM(_n("Hold current truncated to Run current"));
+    }
+
     union IHoldRun {
         struct S {
             uint8_t iHold;
             uint8_t iRun;
             uint16_t iHoldDelay;
             constexpr S(uint8_t ih, uint8_t ir)
-                : iHold(ih)
-                , iRun(ir)
+                : iHold(ih & 0x1F)
+                , iRun(ir & 0x1F)
                 , iHoldDelay(15 & 0x0F) {}
         } s;
         uint32_t dw;
@@ -535,8 +547,7 @@ static void SetCurrents(const uint8_t axis) {
             : s(ih, ir) {}
     };
 
-    // also, make sure iHold never exceeds iRun at runtime
-    IHoldRun ihold_irun((iHold > iRun ? iRun : iHold) & 0x1f, iRun & 0x1f);
+    IHoldRun ihold_irun(iHold, iRun);
 
     tmc2130_wr(axis, TMC2130_REG_IHOLD_IRUN, ihold_irun.dw);
 }