From: tmk <hasu@tmk-kbd.com>
Date: Thu, 1 Mar 2018 17:31:44 +0000 (+0900)
Subject: xt_usb: Read data earlier as possible in ISR
X-Git-Url: https://git.friedersdorff.com/?a=commitdiff_plain;h=ea004061a55033aa5e940c31e34bcdcf4dc0fed3;p=max%2Ftmk_keyboard.git

xt_usb: Read data earlier as possible in ISR
---

diff --git a/tmk_core/protocol/xt_interrupt.c b/tmk_core/protocol/xt_interrupt.c
index 8c8408ba..5531464d 100644
--- a/tmk_core/protocol/xt_interrupt.c
+++ b/tmk_core/protocol/xt_interrupt.c
@@ -93,17 +93,18 @@ ISR(XT_INT_VECT)
     } state = START;
     static uint8_t data = 0;
 
+    uint8_t dbit = data_in();
     // This is needed if using PCINT which can be called on both falling and rising edge
     if (clock_in()) return;
 
     switch (state) {
         case START:
             // ignore start(0) bit
-            if (!data_in()) return;
+            if (!dbit) return;
             break;
         case BIT0 ... BIT7:
             data >>= 1;
-            if (data_in())
+            if (dbit)
                 data |= 0x80;
             break;
     }