i2c: meson: don't create separate token chain just for the stop command

We can directly add the stop token to the token chain including the
last transfer chunk. This is more efficient than creating a separate
token chain just for the stop command.
And it allows us to get rid of state STATE_STOP completely.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/i2c-meson.c

@@ -55,7 +55,6 @@ enum {
 	STATE_IDLE,
 	STATE_READ,
 	STATE_WRITE,
-	STATE_STOP,
 };
 
 /**
@@ -208,19 +207,9 @@ static void meson_i2c_prepare_xfer(struct meson_i2c *i2c)
 
 	if (write)
 		meson_i2c_put_data(i2c, i2c->msg->buf + i2c->pos, i2c->count);
-}
-
-static void meson_i2c_stop(struct meson_i2c *i2c)
-{
-	dev_dbg(i2c->dev, "%s: last %d\n", __func__, i2c->last);
 
-	if (i2c->last) {
-		i2c->state = STATE_STOP;
+	if (i2c->last && i2c->pos + i2c->count >= i2c->msg->len)
 		meson_i2c_add_token(i2c, TOKEN_STOP);
-	} else {
-		i2c->state = STATE_IDLE;
-		complete(&i2c->done);
-	}
 }
 
 static irqreturn_t meson_i2c_irq(int irqno, void *dev_id)
@@ -265,7 +254,8 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id)
 		}
 
 		if (i2c->pos >= i2c->msg->len) {
-			meson_i2c_stop(i2c);
+			i2c->state = STATE_IDLE;
+			complete(&i2c->done);
 			break;
 		}
 
@@ -275,16 +265,13 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id)
 		i2c->pos += i2c->count;
 
 		if (i2c->pos >= i2c->msg->len) {
-			meson_i2c_stop(i2c);
+			i2c->state = STATE_IDLE;
+			complete(&i2c->done);
 			break;
 		}
 
 		meson_i2c_prepare_xfer(i2c);
 		break;
-	case STATE_STOP:
-		i2c->state = STATE_IDLE;
-		complete(&i2c->done);
-		break;
 	}
 
 out: