queue-4.19/drm-imx-imx-ldb-add-missing-of_node_puts.patch

   1 From fa273e562ea7c78c0575598e66eff1d68715a39c Mon Sep 17 00:00:00 2001
   2 From: Julia Lawall <Julia.Lawall@lip6.fr>
   3 Date: Sun, 13 Jan 2019 09:47:42 +0100
   4 Subject: drm/imx: imx-ldb: add missing of_node_puts
   5
   6 [ Upstream commit aa3312012f103f91f123600bbf768b11c8f431bc ]
   7
   8 The device node iterators perform an of_node_get on each
   9 iteration, so a jump out of the loop requires an of_node_put.
  10
  11 Move the initialization channel->child = child; down to just
  12 before the call to imx_ldb_register so that intervening failures
  13 don't need to clear it.  Add a label at the end of the function to
  14 do all the of_node_puts.
  15
  16 The semantic patch that finds part of this problem is as follows
  17 (http://coccinelle.lip6.fr):
  18
  19 // <smpl>
  20 @@
  21 expression root,e;
  22 local idexpression child;
  23 iterator name for_each_child_of_node;
  24 @@
  25
  26  for_each_child_of_node(root, child) {
  27    ... when != of_node_put(child)
  28        when != e = child
  29 (
  30    return child;
  31 |
  32 *  return ...;
  33 )
  34    ...
  35  }
  36 // </smpl>
  37
  38 Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
  39 Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
  40 Signed-off-by: Sasha Levin <sashal@kernel.org>
  41 ---
  42  drivers/gpu/drm/imx/imx-ldb.c | 25 +++++++++++++++++--------
  43  1 file changed, 17 insertions(+), 8 deletions(-)
  44
  45 diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c
  46 index 3bd0f8a18e74..42daa5c9ff8e 100644
  47 --- a/drivers/gpu/drm/imx/imx-ldb.c
  48 +++ b/drivers/gpu/drm/imx/imx-ldb.c
  49 @@ -651,8 +651,10 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
  50                 int bus_format;
  51
  52                 ret = of_property_read_u32(child, "reg", &i);
  53 -               if (ret || i < 0 || i > 1)
  54 -                       return -EINVAL;
  55 +               if (ret || i < 0 || i > 1) {
  56 +                       ret = -EINVAL;
  57 +                       goto free_child;
  58 +               }
  59
  60                 if (!of_device_is_available(child))
  61                         continue;
  62 @@ -665,7 +667,6 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
  63                 channel = &imx_ldb->channel[i];
  64                 channel->ldb = imx_ldb;
  65                 channel->chno = i;
  66 -               channel->child = child;
  67
  68                 /*
  69                  * The output port is port@4 with an external 4-port mux or
  70 @@ -675,13 +676,13 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
  71                                                   imx_ldb->lvds_mux ? 4 : 2, 0,
  72                                                   &channel->panel, &channel->bridge);
  73                 if (ret && ret != -ENODEV)
  74 -                       return ret;
  75 +                       goto free_child;
  76
  77                 /* panel ddc only if there is no bridge */
  78                 if (!channel->bridge) {
  79                         ret = imx_ldb_panel_ddc(dev, channel, child);
  80                         if (ret)
  81 -                               return ret;
  82 +                               goto free_child;
  83                 }
  84
  85                 bus_format = of_get_bus_format(dev, child);
  86 @@ -697,18 +698,26 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
  87                 if (bus_format < 0) {
  88                         dev_err(dev, "could not determine data mapping: %d\n",
  89                                 bus_format);
  90 -                       return bus_format;
  91 +                       ret = bus_format;
  92 +                       goto free_child;
  93                 }
  94                 channel->bus_format = bus_format;
  95 +               channel->child = child;
  96
  97                 ret = imx_ldb_register(drm, channel);
  98 -               if (ret)
  99 -                       return ret;
 100 +               if (ret) {
 101 +                       channel->child = NULL;
 102 +                       goto free_child;
 103 +               }
 104         }
 105
 106         dev_set_drvdata(dev, imx_ldb);
 107
 108         return 0;
 109 +
 110 +free_child:
 111 +       of_node_put(child);
 112 +       return ret;
 113  }
 114
 115  static void imx_ldb_unbind(struct device *dev, struct device *master,
 116 --
 117 2.19.1
 118