From 87f4338b452dea4fdebba3eac573bec999642eb9 Mon Sep 17 00:00:00 2001
From: Michael Gernoth <michael@gernoth.net>
Date: Mon, 23 Aug 2010 17:43:00 +0200
Subject: [PATCH] acknowledge all interrupts when sending, fixes a crash...

---
 bmc/i2c.c | 42 +++++++++++++++++++++++++++++++-----------
 1 file changed, 31 insertions(+), 11 deletions(-)

diff --git a/bmc/i2c.c b/bmc/i2c.c
index 92c00cc..f0816f0 100644
--- a/bmc/i2c.c
+++ b/bmc/i2c.c
@@ -39,34 +39,47 @@ void i2c_send(unsigned char *buf, int len)
 	TWCR = ((1<<TWINT) | (1<<TWSTA) | (1<<TWEN)); /* Send start */
 
 	while(!(TWCR & (1<<TWINT))) {}
-	if ((TW_STATUS & 0xf8) != TW_START)
+	if (TW_STATUS != TW_START) {
+#ifdef DEBUG
+		printf("I2C: error sending START\n");
+#endif
 		goto out;
+	}
 
 	TWDR = buf[0]; /* SLA_W */
 	TWCR = ((1<<TWINT) | (1<<TWEN));
 
 	while(!(TWCR & (1<<TWINT))) {}
-	if ((TW_STATUS & 0xf8) != TW_MT_SLA_ACK)
-		goto out;
+	if (TW_STATUS != TW_MT_SLA_ACK) {
+#ifdef DEBUG
+		printf("I2C: error sending SLA_W\n");
+#endif
+		goto out2;
+	}
 	
 	for(i = 1; i < len; i++) {
 		TWDR = buf[i]; /* Send Data */
 		TWCR = ((1<<TWINT) | (1<<TWEN));
 
 		while(!(TWCR & (1<<TWINT))) {}
-		if ((TW_STATUS & 0xf8) != TW_MT_DATA_ACK)
-			goto out;
+		if (TW_STATUS != TW_MT_DATA_ACK) {
+#ifdef DEBUG
+			printf("I2C: error sending DATA byte %d\n", i);
+#endif
+			goto out2;
+		}
 	}
 
-	TWCR = ((1<<TWINT) | (1<<TWEN) | (1<<TWSTO));
-	while(TWCR & (1<<TWSTO)) {}
-
 #ifdef DEBUG
 	printf("I2C Data sent\n");
 #endif
 
+out2:
+	TWCR = ((1<<TWINT) | (1<<TWEN) | (1<<TWSTO));
+	while(TWCR & (1<<TWSTO)) {}
+
+	TWCR = (1<<TWINT) | (1<<TWEN);
 out:	
-	TWDR = 0x00;
 	TWCR = old_TWCR;
 	SREG = old_SREG;
 }
@@ -76,7 +89,7 @@ ISR (TWI_vect, ISR_BLOCK)
 	if (i2c_done)
 		TWCR_RESET;
 
-	switch (TW_STATUS & 0xf8) {
+	switch (TW_STATUS) {
 		case TW_SR_SLA_ACK:
 #ifdef DEBUG
 			printf("I2C: Slave 0x%02x adressed\n", TWDR);
@@ -111,9 +124,16 @@ ISR (TWI_vect, ISR_BLOCK)
 			TWCR_RESET;
 			break;
 
+		case TW_NO_INFO:
+#ifdef DEBUG
+			printf("I2C: TW_NO_INFO received status 0x%2x\n", TW_STATUS);
+#endif
+			TWCR |= (1<<TWINT);
+			break;
+
 		default:
 #ifdef DEBUG
-			printf("I2C: Unimplemented status 0x%02x\n", (TW_STATUS & 0xf8));
+			printf("I2C: Unimplemented status 0x%02x\n", TW_STATUS);
 #endif
 			TWCR_RESET;
 			break;
-- 
2.39.2