i2c: tegra: notify transfer-complete after clearing status.

The notification of the transfer complete by calling complete()
should be done after clearing all interrupt status.
This avoids the race condition of misconfigure the i2c controller
in multi-core environment.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: stable@kernel.org

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 18067b3ee8c9f215feab9dfa17abd44ce980fe55..8b2e555a9563204476be25184d442d0422a49920 100644 (file)
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -401,8 +401,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
                        disable_irq_nosync(i2c_dev->irq);
                        i2c_dev->irq_disabled = 1;
                }
-
-               complete(&i2c_dev->msg_complete);
                goto err;
        }
 
@@ -411,7 +409,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
                        i2c_dev->msg_err |= I2C_ERR_NO_ACK;
                if (status & I2C_INT_ARBITRATION_LOST)
                        i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST;
-               complete(&i2c_dev->msg_complete);
                goto err;
        }
 
@@ -429,14 +426,14 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
                        tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ);
        }
 
+       i2c_writel(i2c_dev, status, I2C_INT_STATUS);
+       if (i2c_dev->is_dvc)
+               dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
+
        if (status & I2C_INT_PACKET_XFER_COMPLETE) {
                BUG_ON(i2c_dev->msg_buf_remaining);
                complete(&i2c_dev->msg_complete);
        }
-
-       i2c_writel(i2c_dev, status, I2C_INT_STATUS);
-       if (i2c_dev->is_dvc)
-               dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
        return IRQ_HANDLED;
 err:
        /* An error occurred, mask all interrupts */
@@ -446,6 +443,8 @@ err:
        i2c_writel(i2c_dev, status, I2C_INT_STATUS);
        if (i2c_dev->is_dvc)
                dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
+
+       complete(&i2c_dev->msg_complete);
        return IRQ_HANDLED;
 }