V4L/DVB: cx23885: Check for slave nack on all transactions

Don't just check for nacks on zero-length transactions. Check on
other transactions too.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andy Walls <awalls@md.metrocast.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/cx23885/cx23885-i2c.c

@@ -125,6 +125,10 @@ static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
 		goto err;
 	if (retval == 0)
 		goto eio;
+	if (!i2c_slave_did_ack(i2c_adap)) {
+		retval = -ENXIO;
+		goto err;
+	}
 	if (i2c_debug) {
 		printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
 		if (!(ctrl & I2C_NOSTOP))
@@ -214,6 +218,10 @@ static int i2c_readbytes(struct i2c_adapter *i2c_adap,
 			goto err;
 		if (retval == 0)
 			goto eio;
+		if (cnt == 0 && !i2c_slave_did_ack(i2c_adap)) {
+			retval = -ENXIO;
+			goto err;
+		}
 		msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
 		if (i2c_debug) {
 			dprintk(1, " %02x", msg->buf[cnt]);