diff options
| author | Ken Chang <kenc@nvidia.com> | 2012-05-11 15:40:09 +0800 |
|---|---|---|
| committer | Simone Willett <swillett@nvidia.com> | 2012-05-18 13:45:08 -0700 |
| commit | 021d8866c80fab07cb4cd2753ed67d0c1b49c174 (patch) | |
| tree | 359ef051839a3f76dbd9d0185af85955931de3da /drivers/i2c | |
| parent | a763d40775269f8e29fea5780000014178eaf4b3 (diff) | |
i2c: tegra: Fix i2c unknown interrupt issue
writes to modules on APB bus may complete out-of-order. need
to guarantee that the write is completed by reading it back.
read I2C_INT_STATUS back right after writing the current int status
in the isr to make sure the clear operation of I2C_INT_STATUS is
done before the interrupt is re-enabled.
the same also done for DVC_STATUS.
bug 980763
Change-Id: I34f18804d530ccadf561fe1736552b6a4dd6e4ce
Signed-off-by: Ken Chang <kenc@nvidia.com>
Reviewed-on: http://git-master/r/101925
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 25ad6dca3884..96916bed997f 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -583,9 +583,12 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) } i2c_writel(i2c_dev, status, I2C_INT_STATUS); + i2c_readl(i2c_dev, I2C_INT_STATUS); - if (i2c_dev->is_dvc) + if (i2c_dev->is_dvc) { dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + dvc_readl(i2c_dev, DVC_STATUS); + } if (status & I2C_INT_PACKET_XFER_COMPLETE) { BUG_ON(i2c_dev->msg_buf_remaining); @@ -621,13 +624,16 @@ err: I2C_INT_RX_FIFO_DATA_REQ | I2C_INT_TX_FIFO_OVERFLOW); i2c_writel(i2c_dev, status, I2C_INT_STATUS); + i2c_readl(i2c_dev, I2C_INT_STATUS); /* An error occured, mask dvc interrupt */ if (i2c_dev->is_dvc) dvc_i2c_mask_irq(i2c_dev, DVC_CTRL_REG3_I2C_DONE_INTR_EN); - if (i2c_dev->is_dvc) + if (i2c_dev->is_dvc) { dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + dvc_readl(i2c_dev, DVC_STATUS); + } complete(&i2c_dev->msg_complete); return IRQ_HANDLED; |