diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-common.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-common.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c index 2de7452fcd6d..4291ff6246d8 100644 --- a/drivers/i2c/busses/i2c-designware-common.c +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -344,6 +344,28 @@ int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev) return -EIO; } +void i2c_dw_set_fifo_size(struct dw_i2c_dev *dev) +{ + u32 param, tx_fifo_depth, rx_fifo_depth; + + /* + * Try to detect the FIFO depth if not set by interface driver, + * the depth could be from 2 to 256 from HW spec. + */ + param = dw_readl(dev, DW_IC_COMP_PARAM_1); + tx_fifo_depth = ((param >> 16) & 0xff) + 1; + rx_fifo_depth = ((param >> 8) & 0xff) + 1; + if (!dev->tx_fifo_depth) { + dev->tx_fifo_depth = tx_fifo_depth; + dev->rx_fifo_depth = rx_fifo_depth; + } else if (tx_fifo_depth >= 2) { + dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth, + tx_fifo_depth); + dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth, + rx_fifo_depth); + } +} + u32 i2c_dw_func(struct i2c_adapter *adap) { struct dw_i2c_dev *dev = i2c_get_adapdata(adap); |