i2c: imx: Fix reinit_completion() use

commit 9f9e3e0d4dd3338b3f3dde080789f71901e1e4ff upstream.

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

Signed-off-by: Esben Haabendal <eha@deif.com>
Fixes: ce1a78840ff7 ("i2c: imx: add DMA support for freescale i2c driver")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index f96830f..75c6b98 100644 (file)
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -376,6 +376,7 @@ 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))) {
@@ -619,7 +620,6 @@ 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));
@@ -678,7 +678,6 @@ 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));