MLK-14498-3 dma: imx-sdma: avoid dead lock in cyclic case

Avoid dead lock in DMA cyclic case.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index d1e9ece..a440556 100644 (file)
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -746,13 +746,11 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
        struct sdma_desc *desc = sdmac->desc;
        int error = 0;
        enum dma_status old_status = sdmac->status;
-       unsigned long flags;
 
        /*
         * loop mode. Iterate over descriptors, re-setup them and
         * call callback function.
         */
-       spin_lock_irqsave(&sdmac->vc.lock, flags);
        while (desc) {
                bd = &desc->bd[desc->buf_tail];
 
@@ -784,17 +782,16 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
 
                if (error)
                        sdmac->status = old_status;
-               spin_unlock_irqrestore(&sdmac->vc.lock, flags);
                /*
                * The callback is called from the interrupt context in order
                * to reduce latency and to avoid the risk of altering the
                * SDMA transaction status by the time the client tasklet is
                * executed.
                 */
+               spin_unlock(&sdmac->vc.lock);
                dmaengine_desc_get_callback_invoke(&desc->vd.tx, NULL);
-               spin_lock_irqsave(&sdmac->vc.lock, flags);
+               spin_lock(&sdmac->vc.lock);
        }
-       spin_unlock_irqrestore(&sdmac->vc.lock, flags);
 }
 
 static void mxc_sdma_handle_channel_normal(struct sdma_channel *data)