i2c: rcar: refactor TCYC handling

The latest documentation made it clear that we need to initialize the
TCYC value independently of DMA. The old code used TCYC06 (wrongly) for
non-DMA transfers. The new code sets TCYC up independently from DMA.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index 498ba4b87833426559c6049c6b00c68669857b31..dd52a068b140685ecf33c84a79ff89acda8bed26 100644 (file)
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -39,8 +39,8 @@
 #define ICSAR  0x1C    /* slave address */
 #define ICMAR  0x20    /* master address */
 #define ICRXTX 0x24    /* data port */
-#define ICDMAER        0x3c    /* DMA enable */
-#define ICFBSCR        0x38    /* first bit setup cycle */
+#define ICFBSCR        0x38    /* first bit setup cycle (Gen3) */
+#define ICDMAER        0x3c    /* DMA enable (Gen3) */
 
 /* ICSCR */
 #define SDBS   (1 << 3)        /* slave data buffer select */
@@ -83,7 +83,6 @@
 #define TMDMAE (1 << 0)        /* DMA Master Transmitted Enable */
 
 /* ICFBSCR */
-#define TCYC06 0x04            /*  6*Tcyc delay 1st bit between SDA and SCL */
 #define TCYC17 0x0f            /* 17*Tcyc delay 1st bit between SDA and SCL */
 
 
@@ -212,6 +211,10 @@ static void rcar_i2c_init(struct rcar_i2c_priv *priv)
        rcar_i2c_write(priv, ICMSR, 0);
        /* start clock */
        rcar_i2c_write(priv, ICCCR, priv->icccr);
+
+       if (priv->devtype == I2C_RCAR_GEN3)
+               rcar_i2c_write(priv, ICFBSCR, TCYC17);
+
 }
 
 static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
@@ -363,9 +366,6 @@ static void rcar_i2c_dma_unmap(struct rcar_i2c_priv *priv)
        /* Disable DMA Master Received/Transmitted */
        rcar_i2c_write(priv, ICDMAER, 0);
 
-       /* Reset default delay */
-       rcar_i2c_write(priv, ICFBSCR, TCYC06);
-
        dma_unmap_single(chan->device->dev, sg_dma_address(&priv->sg),
                         sg_dma_len(&priv->sg), priv->dma_direction);
 
@@ -461,9 +461,6 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv)
                return;
        }
 
-       /* Set delay for DMA operations */
-       rcar_i2c_write(priv, ICFBSCR, TCYC17);
-
        /* Enable DMA Master Received/Transmitted */
        if (read)
                rcar_i2c_write(priv, ICDMAER, RMDMAE);