Re: [PATCH] dma: mic_x100: add missing spin_unlock

From: Vinod Koul
Date: Mon Nov 30 2015 - 10:24:32 EST


On Mon, Nov 09, 2015 at 06:05:39PM +0530, Saurabh Sengar wrote:
> spin lock should be released while returning from function
>
> Signed-off-by: Saurabh Sengar <saurabh.truth@xxxxxxxxx>
> ---
> drivers/dma/mic_x100_dma.c | 17 +++++++++++------
> 1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/dma/mic_x100_dma.c b/drivers/dma/mic_x100_dma.c
> index 068e920..7f6d477 100644
> --- a/drivers/dma/mic_x100_dma.c
> +++ b/drivers/dma/mic_x100_dma.c
> @@ -317,17 +317,21 @@ mic_dma_prep_memcpy_lock(struct dma_chan *ch, dma_addr_t dma_dest,
> struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
> struct device *dev = mic_dma_ch_to_device(mic_ch);
> int result;
> + struct dma_async_tx_descriptor *tx = NULL;
>
> if (!len && !flags)
> - return NULL;
> + return tx;

This one doesn't make sense, tx will be NULL here, so orignal one is fine

>
> spin_lock(&mic_ch->prep_lock);
> result = mic_dma_do_dma(mic_ch, flags, dma_src, dma_dest, len);
> if (result >= 0)
> - return allocate_tx(mic_ch);
> - dev_err(dev, "Error enqueueing dma, error=%d\n", result);
> + tx = allocate_tx(mic_ch);
> +
> + if(!tx)
> + dev_err(dev, "Error enqueueing dma, error=%d\n", result);
> +
> spin_unlock(&mic_ch->prep_lock);
> - return NULL;
> + return tx;
> }
>
> static struct dma_async_tx_descriptor *
> @@ -335,13 +339,14 @@ mic_dma_prep_interrupt_lock(struct dma_chan *ch, unsigned long flags)
> {
> struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
> int ret;
> + struct dma_async_tx_descriptor *tx = NULL;
>
> spin_lock(&mic_ch->prep_lock);
> ret = mic_dma_do_dma(mic_ch, flags, 0, 0, 0);
> if (!ret)
> - return allocate_tx(mic_ch);
> + tx = allocate_tx(mic_ch);
> spin_unlock(&mic_ch->prep_lock);
> - return NULL;
> + return tx;
> }
>
> /* Return the status of the transaction */
> --
> 1.9.1
>

--
~Vinod
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