PERFORCE change 110638 for review

[Warner Losh]

http://perforce.freebsd.org/chv.cgi?CH=110638

Change 110638 by imp at imp_lighthouse on 2006/11/28 22:34:44

	check for errors too.  Not sure I clear them all correctly, but
	it is a start.
	
	# We wedge something hard, however, when we try to write to a part
	# that doesn't have write enable asserted.

Affected files ...

.. //depot/projects/arm/src/sys/arm/at91/at91_twi.c#30 edit

Differences ...

==== //depot/projects/arm/src/sys/arm/at91/at91_twi.c#30 (text+ko) ====

@@ -204,10 +204,10 @@
 	struct at91_twi_softc *sc = xsc;
 	uint32_t status;
 
-	/* Reading the status also clears the interrupt */
 	status = RD4(sc, TWI_SR);
 	if (status == 0)
 		return;
+	sc->flags |= status & (TWI_SR_OVRE | TWI_SR_UNRE | TWI_SR_NACK);
 	if (status & TWI_SR_RXRDY)
 		sc->flags |= TWI_SR_RXRDY;
 	if (status & TWI_SR_TXRDY)
@@ -227,7 +227,9 @@
 	sc->flags = 0;
 	WR4(sc, TWI_IER, bit);
 	err = msleep(sc, &sc->sc_mtx, PZERO | PCATCH, "iic", MAX(1,hz/10));
-	if (sc->flags & bit)
+	if (sc->flags & ~bit)
+		err = EIO;
+	else if (sc->flags & bit)
 		err = 0;
 	else if (err == 0)
 		err = EBUSY;