git.openwrt.org Git - openwrt/staging/ldir.git/blob

   1 From 89885c09160b04ae2eec82cf9b35117ff6aa4c5d Mon Sep 17 00:00:00 2001
   2 From: Robin Gong <yibin.gong@nxp.com>
   3 Date: Wed, 8 May 2019 00:13:40 +0800
   4 Subject: [PATCH] MLK-22284-2 dmaengine: fsl-edma-v3: check dma description
   5  before register touch
   6
   7 Check dma desscription firstly to ignore any unexpected interrupt
   8 after channel terminate, otherwise, still have chance to touch channel
   9 register whose power has been already off.
  10
  11 Signed-off-by: Robin Gong <yibin.gong@nxp.com>
  12 Reviewed-by: S.j. Wang <shengjiu.wang@nxp.com>
  13 (cherry picked from commit fd073e017e317006a4c254ca5ae3ea17b6f32502)
  14 ---
  15  drivers/dma/fsl-edma-v3.c | 14 +++++++-------
  16  1 file changed, 7 insertions(+), 7 deletions(-)
  17
  18 --- a/drivers/dma/fsl-edma-v3.c
  19 +++ b/drivers/dma/fsl-edma-v3.c
  20 @@ -708,20 +708,20 @@ static irqreturn_t fsl_edma3_tx_handler(
  21         unsigned int intr;
  22         void __iomem *base_addr;
  23
  24 +       spin_lock(&fsl_chan->vchan.lock);
  25 +
  26 +       /* Ignore this interrupt since channel has been disabled already */
  27 +       if (!fsl_chan->edesc)
  28 +               goto irq_handled;
  29 +
  30         base_addr = fsl_chan->membase;
  31
  32         intr = readl(base_addr + EDMA_CH_INT);
  33         if (!intr)
  34 -               return IRQ_NONE;
  35 +               goto irq_handled;
  36
  37         writel(1, base_addr + EDMA_CH_INT);
  38
  39 -       spin_lock(&fsl_chan->vchan.lock);
  40 -
  41 -       /* Ignore this interrupt since channel has been disabled already */
  42 -       if (!fsl_chan->edesc)
  43 -               goto irq_handled;
  44 -
  45         if (!fsl_chan->edesc->iscyclic) {
  46                 fsl_edma3_get_realcnt(fsl_chan);
  47                 list_del(&fsl_chan->edesc->vdesc.node);