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fsl_i2c: Do not generate STOP after read.

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__i2c_read always ends with a STOP condition thereby releasing
the bus. It is cleaner to do the STOP magic in i2c_read(), like
i2c_write() does. This may also help future multimaster systems which
wants to hold on to the bus until all transactions are finished.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
This commit is contained in:
Joakim Tjernlund 2009-09-22 13:40:44 +02:00 committed by Heiko Schocher
parent 9940420212
commit d1c9e5b379
1 changed files with 6 additions and 5 deletions
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11
drivers/i2c/fsl_i2c.c
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@ -353,9 +353,10 @@ __i2c_read(u8 *data, int length)
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_TXAK,
&i2c_dev[i2c_bus_num]->cr);
/* Generate stop on last byte */
/* Do not generate stop on last byte */
if (i == length - 1)
writeb(I2C_CR_MEN | I2C_CR_TXAK, &i2c_dev[i2c_bus_num]->cr);
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX,
&i2c_dev[i2c_bus_num]->cr);
data[i] = readb(&i2c_dev[i2c_bus_num]->dr);
}
@ -378,11 +379,11 @@ i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
&& i2c_write_addr(dev, I2C_READ_BIT, 1) != 0)
i = __i2c_read(data, length);
if (length && i2c_wait4bus()) /* Wait until STOP */
debug("i2c_read: wait4bus timed out\n");
writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr);
if (i2c_wait4bus()) /* Wait until STOP */
debug("i2c_read: wait4bus timed out\n");
if (i == length)
return 0;