i2c: algo-bit: add support for I2C_M_STOP

Support for enforced STOPs will allow us to use SCCB compatible devices.

Based on a preliminary patch by Wolfram Sang.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Tested-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

drivers/i2c/algos/i2c-algo-bit.c

@@ -553,9 +553,16 @@ static int bit_xfer(struct i2c_adapter *i2c_adap,
 		nak_ok = pmsg->flags & I2C_M_IGNORE_NAK;
 		if (!(pmsg->flags & I2C_M_NOSTART)) {
 			if (i) {
-				bit_dbg(3, &i2c_adap->dev, "emitting "
-					"repeated start condition\n");
-				i2c_repstart(adap);
+				if (msgs[i - 1].flags & I2C_M_STOP) {
+					bit_dbg(3, &i2c_adap->dev,
+						"emitting enforced stop/start condition\n");
+					i2c_stop(adap);
+					i2c_start(adap);
+				} else {
+					bit_dbg(3, &i2c_adap->dev,
+						"emitting repeated start condition\n");
+					i2c_repstart(adap);
+				}
 			}
 			ret = bit_doAddress(i2c_adap, pmsg);
 			if ((ret != 0) && !nak_ok) {