diff options
| author | Joakim Tjernlund <Joakim.Tjernlund@transmode.se> | 2009-10-13 10:12:03 +0200 |
|---|---|---|
| committer | Ben Dooks <ben-linux@fluff.org> | 2009-11-03 00:28:47 +0100 |
| commit | 45da790ebe746bb29f7e4adf806c020db6ff7755 (patch) | |
| tree | 0aa6a12cb9b128dd2bde8d71466e878420bc67c0 /drivers | |
| parent | i2c: imx: disable clock when it's possible to save power. (diff) | |
| download | linux-45da790ebe746bb29f7e4adf806c020db6ff7755.tar.xz linux-45da790ebe746bb29f7e4adf806c020db6ff7755.zip | |
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>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/i2c/busses/i2c-mpc.c | 10 |
1 files changed, 2 insertions, 8 deletions
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index d325e86e3103..f627001108b8 100644 --- 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); } |