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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>
This commit is contained in:
Joakim Tjernlund 2009-10-13 10:12:03 +02:00 committed by Ben Dooks
parent db3a3d4ef7
commit 45da790ebe
1 changed files with 2 additions and 8 deletions
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10
drivers/i2c/busses/i2c-mpc.c
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@ -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);
}