releases/4.19.31/media-imx-csi-disable-csi-immediately-after-last-eof.patch

   1 From 2e0fe66e0a136252f4d89dbbccdcb26deb867eb8 Mon Sep 17 00:00:00 2001
   2 From: Steve Longerbeam <slongerbeam@gmail.com>
   3 Date: Mon, 21 Jan 2019 21:35:50 -0200
   4 Subject: media: imx: csi: Disable CSI immediately after last EOF
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   8
   9 From: Steve Longerbeam <slongerbeam@gmail.com>
  10
  11 commit 2e0fe66e0a136252f4d89dbbccdcb26deb867eb8 upstream.
  12
  13 Disable the CSI immediately after receiving the last EOF before stream
  14 off (and thus before disabling the IDMA channel). Do this by moving the
  15 wait for EOF completion into a new function csi_idmac_wait_last_eof().
  16
  17 This fixes a complete system hard lockup on the SabreAuto when streaming
  18 from the ADV7180, by repeatedly sending a stream off immediately followed
  19 by stream on:
  20
  21 while true; do v4l2-ctl  -d4 --stream-mmap --stream-count=3; done
  22
  23 Eventually this either causes the system lockup or EOF timeouts at all
  24 subsequent stream on, until a system reset.
  25
  26 The lockup occurs when disabling the IDMA channel at stream off. Disabling
  27 the CSI before disabling the IDMA channel appears to be a reliable fix for
  28 the hard lockup.
  29
  30 Fixes: 4a34ec8e470cb ("[media] media: imx: Add CSI subdev driver")
  31
  32 Reported-by: Gaël PORTAY <gael.portay@collabora.com>
  33 Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
  34 Cc: stable@vger.kernel.org      # for 4.13 and up
  35 Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
  36 Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
  37 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  38
  39 ---
  40  drivers/staging/media/imx/imx-media-csi.c |   17 ++++++++++++++---
  41  1 file changed, 14 insertions(+), 3 deletions(-)
  42
  43 --- a/drivers/staging/media/imx/imx-media-csi.c
  44 +++ b/drivers/staging/media/imx/imx-media-csi.c
  45 @@ -626,7 +626,7 @@ out_put_ipu:
  46         return ret;
  47  }
  48
  49 -static void csi_idmac_stop(struct csi_priv *priv)
  50 +static void csi_idmac_wait_last_eof(struct csi_priv *priv)
  51  {
  52         unsigned long flags;
  53         int ret;
  54 @@ -643,7 +643,10 @@ static void csi_idmac_stop(struct csi_pr
  55                 &priv->last_eof_comp, msecs_to_jiffies(IMX_MEDIA_EOF_TIMEOUT));
  56         if (ret == 0)
  57                 v4l2_warn(&priv->sd, "wait last EOF timeout\n");
  58 +}
  59
  60 +static void csi_idmac_stop(struct csi_priv *priv)
  61 +{
  62         devm_free_irq(priv->dev, priv->eof_irq, priv);
  63         devm_free_irq(priv->dev, priv->nfb4eof_irq, priv);
  64
  65 @@ -755,6 +758,16 @@ idmac_stop:
  66
  67  static void csi_stop(struct csi_priv *priv)
  68  {
  69 +       if (priv->dest == IPU_CSI_DEST_IDMAC)
  70 +               csi_idmac_wait_last_eof(priv);
  71 +
  72 +       /*
  73 +        * Disable the CSI asap, after syncing with the last EOF.
  74 +        * Doing so after the IDMA channel is disabled has shown to
  75 +        * create hard system-wide hangs.
  76 +        */
  77 +       ipu_csi_disable(priv->csi);
  78 +
  79         if (priv->dest == IPU_CSI_DEST_IDMAC) {
  80                 csi_idmac_stop(priv);
  81
  82 @@ -762,8 +775,6 @@ static void csi_stop(struct csi_priv *pr
  83                 if (priv->fim)
  84                         imx_media_fim_set_stream(priv->fim, NULL, false);
  85         }
  86 -
  87 -       ipu_csi_disable(priv->csi);
  88  }
  89
  90  static const struct csi_skip_desc csi_skip[12] = {