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