From 3fbd882b439bb0ad2788b8cba12eb92a207d6602 Mon Sep 17 00:00:00 2001 From: Sricharan R Date: Fri, 28 Jun 2019 17:39:46 +0530 Subject: [PATCH] dmaengine: qcom: bam_dma: Fix completed descriptors count BugLink: https://bugs.launchpad.net/bugs/1838824 commit f6034225442c4a87906d36e975fd9e99a8f95487 upstream. 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@vger.kernel.org Reported-by: Srinivas Kandagatla Signed-off-by: Sricharan R Tested-by: Srinivas Kandagatla Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman Signed-off-by: Kamal Mostafa Signed-off-by: Khalid Elmously --- 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 4cc58904ee52..87fe5fef1858 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 */ -- 2.39.5