diff options
| -rw-r--r-- | drivers/i2c/busses/i2c-pnx.c | 48 | ||||
| -rw-r--r-- | include/linux/i2c-pnx.h | 1 |
2 files changed, 29 insertions, 20 deletions
diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c index b36e21f9fd53..8488bddfe465 100644 --- a/drivers/i2c/busses/i2c-pnx.c +++ b/drivers/i2c/busses/i2c-pnx.c @@ -291,31 +291,37 @@ static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data) * or we didn't 'ask' for it yet. */ if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) { - dev_dbg(&alg_data->adapter.dev, - "%s(): Write dummy data to fill Rx-fifo...\n", - __func__); + /* 'Asking' is done asynchronously, e.g. dummy TX of several + * bytes is done before the first actual RX arrives in FIFO. + * Therefore, ordered bytes (via TX) are counted separately. + */ + if (alg_data->mif.order) { + dev_dbg(&alg_data->adapter.dev, + "%s(): Write dummy data to fill Rx-fifo...\n", + __func__); - if (alg_data->mif.len == 1) { - /* Last byte, do not acknowledge next rcv. */ - val |= stop_bit; + if (alg_data->mif.order == 1) { + /* Last byte, do not acknowledge next rcv. */ + val |= stop_bit; + + /* + * Enable interrupt RFDAIE (data in Rx fifo), + * and disable DRMIE (need data for Tx) + */ + ctl = ioread32(I2C_REG_CTL(alg_data)); + ctl |= mcntrl_rffie | mcntrl_daie; + ctl &= ~mcntrl_drmie; + iowrite32(ctl, I2C_REG_CTL(alg_data)); + } /* - * Enable interrupt RFDAIE (data in Rx fifo), - * and disable DRMIE (need data for Tx) + * Now we'll 'ask' for data: + * For each byte we want to receive, we must + * write a (dummy) byte to the Tx-FIFO. */ - ctl = ioread32(I2C_REG_CTL(alg_data)); - ctl |= mcntrl_rffie | mcntrl_daie; - ctl &= ~mcntrl_drmie; - iowrite32(ctl, I2C_REG_CTL(alg_data)); + iowrite32(val, I2C_REG_TX(alg_data)); + alg_data->mif.order--; } - - /* - * Now we'll 'ask' for data: - * For each byte we want to receive, we must - * write a (dummy) byte to the Tx-FIFO. - */ - iowrite32(val, I2C_REG_TX(alg_data)); - return 0; } @@ -515,6 +521,7 @@ i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) alg_data->mif.buf = pmsg->buf; alg_data->mif.len = pmsg->len; + alg_data->mif.order = pmsg->len; alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ? I2C_SMBUS_READ : I2C_SMBUS_WRITE; alg_data->mif.ret = 0; @@ -567,6 +574,7 @@ i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) /* Cleanup to be sure... */ alg_data->mif.buf = NULL; alg_data->mif.len = 0; + alg_data->mif.order = 0; dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n", __func__, ioread32(I2C_REG_STS(alg_data))); diff --git a/include/linux/i2c-pnx.h b/include/linux/i2c-pnx.h index 1bc74afe7a35..49ed17fdf055 100644 --- a/include/linux/i2c-pnx.h +++ b/include/linux/i2c-pnx.h @@ -22,6 +22,7 @@ struct i2c_pnx_mif { struct timer_list timer; /* Timeout */ u8 * buf; /* Data buffer */ int len; /* Length of data buffer */ + int order; /* RX Bytes to order via TX */ }; struct i2c_pnx_algo_data { |