Re: [PATCH] dmaengine: qcom: bam_dma: Fix completed descriptors count

[Srinivas Kandagatla]

On 28/06/2019 13:09, Sricharan R wrote:
> One space is left unused in circular FIFO to differentiate
> 'full' and 'empty' cases. So take that in to account while
> counting for the descriptors completed.
>
> Fixes the issue reported here,
> 	https://lkml.org/lkml/2019/6/18/669
>
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>

Thanks for the patch, It works for me now!

Tested-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

--srini

> ---
>   drivers/dma/qcom/bam_dma.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
> index 4b43844..8e90a40 100644
> --- a/drivers/dma/qcom/bam_dma.c
> +++ b/drivers/dma/qcom/bam_dma.c
> @@ -799,6 +799,9 @@ static u32 process_channel_irqs(struct bam_device *bdev)
>   		/* Number of bytes available to read */
>   		avail = CIRC_CNT(offset, bchan->head, MAX_DESCRIPTORS + 1);
>   
> +		if (offset < bchan->head)
> +			avail--;
> +
>   		list_for_each_entry_safe(async_desc, tmp,
>   					 &bchan->desc_list, desc_node) {
>   			/* Not enough data to read */