i2c-mpc: Do not generate STOP after read.

The driver always ends a read with a STOP condition which
breaks subsequent I2C reads/writes in the same transaction as
these expect to do a repeated START(ReSTART).

This will also help I2C multimaster as the bus will not be released
after the first read, but when the whole transaction ends.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index d325e86..f627001 100644 (file)
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -365,9 +365,6 @@ static int mpc_write(struct mpc_i2c *i2c, int target,
        unsigned timeout = i2c->adap.timeout;
        u32 flags = restart ? CCR_RSTA : 0;
 
-       /* Start with MEN */
-       if (!restart)
-               writeccr(i2c, CCR_MEN);
        /* Start as master */
        writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
        /* Write target byte */
@@ -396,9 +393,6 @@ static int mpc_read(struct mpc_i2c *i2c, int target,
        int i, result;
        u32 flags = restart ? CCR_RSTA : 0;
 
-       /* Start with MEN */
-       if (!restart)
-               writeccr(i2c, CCR_MEN);
        /* Switch to read - restart */
        writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
        /* Write target address byte - this time with the read flag set */
@@ -425,9 +419,9 @@ static int mpc_read(struct mpc_i2c *i2c, int target,
                /* Generate txack on next to last byte */
                if (i == length - 2)
                        writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
-               /* Generate stop on last byte */
+               /* Do not generate stop on last byte */
                if (i == length - 1)
-                       writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_TXAK);
+                       writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX);
                data[i] = readb(i2c->base + MPC_I2C_DR);
        }