From 00f5ed6b4516f5f39576089b5367f31e15fa6998 Mon Sep 17 00:00:00 2001
From: Cristian Maglie <c.maglie@bug.st>
Date: Tue, 18 Nov 2014 20:02:27 +0100
Subject: [avr] Made SPI.usingInterrupt() synchronized (Andrew Kroll)
---
libraries/SPI/SPI.cpp | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/libraries/SPI/SPI.cpp b/libraries/SPI/SPI.cpp
index 40d4278..077b6a3 100644
--- a/libraries/SPI/SPI.cpp
+++ b/libraries/SPI/SPI.cpp
@@ -111,11 +111,9 @@ void SPIClass::end() {
void SPIClass::usingInterrupt(uint8_t interruptNumber)
{
- uint8_t mask;
-
- if (interruptMode > 1) return;
-
- noInterrupts();
+ uint8_t mask = 0;
+ uint8_t sreg = SREG;
+ noInterrupts(); // Protect from a scheduler and prevent transactionBegin
switch (interruptNumber) {
#ifdef SPI_INT0_MASK
case 0: mask = SPI_INT0_MASK; break;
@@ -143,12 +141,12 @@ void SPIClass::usingInterrupt(uint8_t interruptNumber)
#endif
default:
interruptMode = 2;
- interrupts();
- return;
+ break;
}
- interruptMode = 1;
interruptMask |= mask;
- interrupts();
+ if (!interruptMode)
+ interruptMode = 1;
+ SREG = sreg;
}
void SPIClass::notUsingInterrupt(uint8_t interruptNumber)
--
cgit v1.2.3-18-g5258