[PATCH 1/4] i2c: imx: Fix reinit_completion() use

From: Esben Haabendal
Date: Wed May 23 2018 - 05:03:05 EST


From: Esben Haabendal <eha@xxxxxxxx>

Make sure to call reinit_completion() before dma is started to avoid race
condition where reinit_compleition() is called after complete() and before
wait_for_completion_timeout().

Signed-off-by: Esben Haabendal <eha@xxxxxxxx>
---
drivers/i2c/busses/i2c-imx.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index d7267dd9c7bf..6fca5e64cffb 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -377,6 +377,7 @@ static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx,
goto err_desc;
}

+ reinit_completion(&dma->cmd_complete);
txdesc->callback = i2c_imx_dma_callback;
txdesc->callback_param = i2c_imx;
if (dma_submit_error(dmaengine_submit(txdesc))) {
@@ -631,7 +632,6 @@ static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx,
* The first byte must be transmitted by the CPU.
*/
imx_i2c_write_reg(msgs->addr << 1, i2c_imx, IMX_I2C_I2DR);
- reinit_completion(&i2c_imx->dma->cmd_complete);
time_left = wait_for_completion_timeout(
&i2c_imx->dma->cmd_complete,
msecs_to_jiffies(DMA_TIMEOUT));
@@ -690,7 +690,6 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
if (result)
return result;

- reinit_completion(&i2c_imx->dma->cmd_complete);
time_left = wait_for_completion_timeout(
&i2c_imx->dma->cmd_complete,
msecs_to_jiffies(DMA_TIMEOUT));
--
2.17.0