Merge tag 'mxs-fixes-3.10' of git://git.linaro.org/people/shawnguo/linux-2.6 into...

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / i2c / busses / i2c-designware-core.c

diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 21fbb340ad6603a249d052d8f7accb6aed0f7753..c41ca6354fc59d8d2111dfdbbb47bdab87f725a8 100644 (file)
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -383,7 +383,8 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
        /* Enable the adapter */
        __i2c_dw_enable(dev, true);
 
-       /* Enable interrupts */
+       /* Clear and enable interrupts */
+       i2c_dw_clear_int(dev);
        dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK);
 }
 
@@ -448,8 +449,14 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
                                cmd |= BIT(9);
 
                        if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
+
+                               /* avoid rx buffer overrun */
+                               if (rx_limit - dev->rx_outstanding <= 0)
+                                       break;
+
                                dw_writel(dev, cmd | 0x100, DW_IC_DATA_CMD);
                                rx_limit--;
+                               dev->rx_outstanding++;
                        } else
                                dw_writel(dev, cmd | *buf++, DW_IC_DATA_CMD);
                        tx_limit--; buf_len--;
@@ -502,8 +509,10 @@ i2c_dw_read(struct dw_i2c_dev *dev)
 
                rx_valid = dw_readl(dev, DW_IC_RXFLR);
 
-               for (; len > 0 && rx_valid > 0; len--, rx_valid--)
+               for (; len > 0 && rx_valid > 0; len--, rx_valid--) {
                        *buf++ = dw_readl(dev, DW_IC_DATA_CMD);
+                       dev->rx_outstanding--;
+               }
 
                if (len > 0) {
                        dev->status |= STATUS_READ_IN_PROGRESS;
@@ -561,6 +570,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
        dev->msg_err = 0;
        dev->status = STATUS_IDLE;
        dev->abort_source = 0;
+       dev->rx_outstanding = 0;
 
        ret = i2c_dw_wait_bus_not_busy(dev);
        if (ret < 0)