target/linux/sunxi/patches-3.14/175-reset-add-of_reset_control_get.patch

   1 From bfea2b9be28b20e076d5df8863c25e966f413fa3 Mon Sep 17 00:00:00 2001
   2 From: Maxime Ripard <maxime.ripard@free-electrons.com>
   3 Date: Fri, 20 Dec 2013 22:41:07 +0100
   4 Subject: [PATCH] reset: Add of_reset_control_get
   5
   6 In some cases, you might need to deassert from reset an hardware block that
   7 doesn't associated to a struct device (CPUs, timers, etc.).
   8
   9 Add a small helper to retrieve the reset controller from the device tree
  10 without the need to pass a struct device.
  11
  12 Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
  13 ---
  14  drivers/reset/core.c  | 39 ++++++++++++++++++++++++++++++---------
  15  include/linux/reset.h |  4 ++++
  16  2 files changed, 34 insertions(+), 9 deletions(-)
  17
  18 diff --git a/drivers/reset/core.c b/drivers/reset/core.c
  19 index d1b6089..4f3dda7 100644
  20 --- a/drivers/reset/core.c
  21 +++ b/drivers/reset/core.c
  22 @@ -127,15 +127,16 @@ int reset_control_deassert(struct reset_control *rstc)
  23  EXPORT_SYMBOL_GPL(reset_control_deassert);
  24
  25  /**
  26 - * reset_control_get - Lookup and obtain a reference to a reset controller.
  27 - * @dev: device to be reset by the controller
  28 + * of_reset_control_get - Lookup and obtain a reference to a reset controller.
  29 + * @node: device to be reset by the controller
  30   * @id: reset line name
  31   *
  32   * Returns a struct reset_control or IS_ERR() condition containing errno.
  33   *
  34   * Use of id names is optional.
  35   */
  36 -struct reset_control *reset_control_get(struct device *dev, const char *id)
  37 +struct reset_control *of_reset_control_get(struct device_node *node,
  38 +                                          const char *id)
  39  {
  40         struct reset_control *rstc = ERR_PTR(-EPROBE_DEFER);
  41         struct reset_controller_dev *r, *rcdev;
  42 @@ -144,13 +145,10 @@ struct reset_control *reset_control_get(struct device *dev, const char *id)
  43         int rstc_id;
  44         int ret;
  45
  46 -       if (!dev)
  47 -               return ERR_PTR(-EINVAL);
  48 -
  49         if (id)
  50 -               index = of_property_match_string(dev->of_node,
  51 +               index = of_property_match_string(node,
  52                                                  "reset-names", id);
  53 -       ret = of_parse_phandle_with_args(dev->of_node, "resets", "#reset-cells",
  54 +       ret = of_parse_phandle_with_args(node, "resets", "#reset-cells",
  55                                          index, &args);
  56         if (ret)
  57                 return ERR_PTR(ret);
  58 @@ -185,12 +183,35 @@ struct reset_control *reset_control_get(struct device *dev, const char *id)
  59                 return ERR_PTR(-ENOMEM);
  60         }
  61
  62 -       rstc->dev = dev;
  63         rstc->rcdev = rcdev;
  64         rstc->id = rstc_id;
  65
  66         return rstc;
  67  }
  68 +EXPORT_SYMBOL_GPL(of_reset_control_get);
  69 +
  70 +/**
  71 + * reset_control_get - Lookup and obtain a reference to a reset controller.
  72 + * @dev: device to be reset by the controller
  73 + * @id: reset line name
  74 + *
  75 + * Returns a struct reset_control or IS_ERR() condition containing errno.
  76 + *
  77 + * Use of id names is optional.
  78 + */
  79 +struct reset_control *reset_control_get(struct device *dev, const char *id)
  80 +{
  81 +       struct reset_control *rstc;
  82 +
  83 +       if (!dev)
  84 +               return ERR_PTR(-EINVAL);
  85 +
  86 +       rstc = of_reset_control_get(dev->of_node, id);
  87 +       if (!IS_ERR(rstc))
  88 +               rstc->dev = dev;
  89 +
  90 +       return rstc;
  91 +}
  92  EXPORT_SYMBOL_GPL(reset_control_get);
  93
  94  /**
  95 diff --git a/include/linux/reset.h b/include/linux/reset.h
  96 index 6082247..a398025 100644
  97 --- a/include/linux/reset.h
  98 +++ b/include/linux/reset.h
  99 @@ -1,6 +1,8 @@
 100  #ifndef _LINUX_RESET_H_
 101  #define _LINUX_RESET_H_
 102
 103 +#include <linux/of.h>
 104 +
 105  struct device;
 106  struct reset_control;
 107
 108 @@ -8,6 +10,8 @@ int reset_control_reset(struct reset_control *rstc);
 109  int reset_control_assert(struct reset_control *rstc);
 110  int reset_control_deassert(struct reset_control *rstc);
 111
 112 +struct reset_control *of_reset_control_get(struct device_node *node,
 113 +                                          const char *id);
 114  struct reset_control *reset_control_get(struct device *dev, const char *id);
 115  void reset_control_put(struct reset_control *rstc);
 116  struct reset_control *devm_reset_control_get(struct device *dev, const char *id);
 117 --
 118 2.0.3
 119