From 2eb9f241824d000fcd90bd7f4b49e40b88e62975 Mon Sep 17 00:00:00 2001 From: Marcus Comstedt Date: Sat, 28 May 2011 16:55:52 +0200 Subject: bitbang_i2c: Fix spurious slave read after NACK After NACKing a read operation, a raising SCL should not trigger a new read from the slave. Introduce a new state which just waits for a stop or start condition after NACK. Signed-off-by: Marcus Comstedt Signed-off-by: Andrzej Zaborowski --- hw/bitbang_i2c.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'hw') diff --git a/hw/bitbang_i2c.c b/hw/bitbang_i2c.c index 4ee99a18b9..2937b5c4a1 100644 --- a/hw/bitbang_i2c.c +++ b/hw/bitbang_i2c.c @@ -38,7 +38,8 @@ typedef enum bitbang_i2c_state { RECEIVING_BIT2, RECEIVING_BIT1, RECEIVING_BIT0, - SENDING_ACK + SENDING_ACK, + SENT_NACK } bitbang_i2c_state; struct bitbang_i2c_interface { @@ -115,6 +116,7 @@ int bitbang_i2c_set(bitbang_i2c_interface *i2c, int line, int level) } switch (i2c->state) { case STOPPED: + case SENT_NACK: return bitbang_i2c_ret(i2c, 1); case SENDING_BIT7 ... SENDING_BIT0: @@ -155,6 +157,7 @@ int bitbang_i2c_set(bitbang_i2c_interface *i2c, int line, int level) i2c->state = RECEIVING_BIT7; if (data != 0) { DPRINTF("NACKED\n"); + i2c->state = SENT_NACK; i2c_nack(i2c->bus); } else { DPRINTF("ACKED\n"); -- cgit v1.2.3