i2c: rcar: use flags instead of atomic_xfer

i2c-rcar already has priv->flags. This patch adds a new persistent flag
ID_P_NOT_ATOMIC and uses it to save the extra variable. The negation of
the logic was done to make the code more readable.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[wsa: negated the logic, rebased, updated the commit message]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Author: morimoto

drivers/i2c/busses/i2c-rcar.c

@@ -104,10 +104,11 @@
 #define ID_NACK			BIT(4)
 #define ID_EPROTO		BIT(5)
 /* persistent flags */
+#define ID_P_NOT_ATOMIC		BIT(28)
 #define ID_P_HOST_NOTIFY	BIT(29)
 #define ID_P_NO_RXDMA		BIT(30) /* HW forbids RXDMA sometimes */
 #define ID_P_PM_BLOCKED		BIT(31)
-#define ID_P_MASK		GENMASK(31, 29)
+#define ID_P_MASK		GENMASK(31, 28)
 
 enum rcar_i2c_type {
 	I2C_RCAR_GEN1,
@@ -138,7 +139,6 @@ struct rcar_i2c_priv {
 	enum dma_data_direction dma_direction;
 
 	struct reset_control *rstc;
-	bool atomic_xfer;
 	int irq;
 
 	struct i2c_client *host_notify_client;
@@ -350,7 +350,7 @@ static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
 		priv->flags |= ID_LAST_MSG;
 
 	rcar_i2c_write(priv, ICMAR, i2c_8bit_addr_from_msg(priv->msg));
-	if (!priv->atomic_xfer)
+	if (priv->flags & ID_P_NOT_ATOMIC)
 		rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
 
 	if (rep_start)
@@ -420,7 +420,7 @@ static bool rcar_i2c_dma(struct rcar_i2c_priv *priv)
 	int len;
 
 	/* Do various checks to see if DMA is feasible at all */
-	if (priv->atomic_xfer || IS_ERR(chan) || msg->len < RCAR_MIN_DMA_LEN ||
+	if (!(priv->flags & ID_P_NOT_ATOMIC) || IS_ERR(chan) || msg->len < RCAR_MIN_DMA_LEN ||
 	    !(msg->flags & I2C_M_DMA_SAFE) || (read && priv->flags & ID_P_NO_RXDMA))
 		return false;
 
@@ -670,7 +670,7 @@ static irqreturn_t rcar_i2c_irq(int irq, struct rcar_i2c_priv *priv, u32 msr)
 	/* Nack */
 	if (msr & MNR) {
 		/* HW automatically sends STOP after received NACK */
-		if (!priv->atomic_xfer)
+		if (priv->flags & ID_P_NOT_ATOMIC)
 			rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP);
 		priv->flags |= ID_NACK;
 		goto out;
@@ -692,7 +692,7 @@ static irqreturn_t rcar_i2c_irq(int irq, struct rcar_i2c_priv *priv, u32 msr)
 	if (priv->flags & ID_DONE) {
 		rcar_i2c_write(priv, ICMIER, 0);
 		rcar_i2c_write(priv, ICMSR, 0);
-		if (!priv->atomic_xfer)
+		if (priv->flags & ID_P_NOT_ATOMIC)
 			wake_up(&priv->wait);
 	}
 
@@ -710,7 +710,7 @@ static irqreturn_t rcar_i2c_gen2_irq(int irq, void *ptr)
 
 	/* Only handle interrupts that are currently enabled */
 	msr = rcar_i2c_read(priv, ICMSR);
-	if (!priv->atomic_xfer)
+	if (priv->flags & ID_P_NOT_ATOMIC)
 		msr &= rcar_i2c_read(priv, ICMIER);
 
 	return rcar_i2c_irq(irq, priv, msr);
@@ -723,7 +723,7 @@ static irqreturn_t rcar_i2c_gen3_irq(int irq, void *ptr)
 
 	/* Only handle interrupts that are currently enabled */
 	msr = rcar_i2c_read(priv, ICMSR);
-	if (!priv->atomic_xfer)
+	if (priv->flags & ID_P_NOT_ATOMIC)
 		msr &= rcar_i2c_read(priv, ICMIER);
 
 	/*
@@ -832,7 +832,7 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 	int i, ret;
 	long time_left;
 
-	priv->atomic_xfer = false;
+	priv->flags |= ID_P_NOT_ATOMIC;
 
 	pm_runtime_get_sync(dev);
 
@@ -896,7 +896,7 @@ static int rcar_i2c_master_xfer_atomic(struct i2c_adapter *adap,
 	bool time_left;
 	int ret;
 
-	priv->atomic_xfer = true;
+	priv->flags &= ~ID_P_NOT_ATOMIC;
 
 	pm_runtime_get_sync(dev);