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 --- a/drivers/reset/core.c
  19 +++ b/drivers/reset/core.c
  20 @@ -127,15 +127,16 @@ int reset_control_deassert(struct reset_
  21  EXPORT_SYMBOL_GPL(reset_control_deassert);
  22
  23  /**
  24 - * reset_control_get - Lookup and obtain a reference to a reset controller.
  25 - * @dev: device to be reset by the controller
  26 + * of_reset_control_get - Lookup and obtain a reference to a reset controller.
  27 + * @node: device to be reset by the controller
  28   * @id: reset line name
  29   *
  30   * Returns a struct reset_control or IS_ERR() condition containing errno.
  31   *
  32   * Use of id names is optional.
  33   */
  34 -struct reset_control *reset_control_get(struct device *dev, const char *id)
  35 +struct reset_control *of_reset_control_get(struct device_node *node,
  36 +                                          const char *id)
  37  {
  38         struct reset_control *rstc = ERR_PTR(-EPROBE_DEFER);
  39         struct reset_controller_dev *r, *rcdev;
  40 @@ -144,13 +145,10 @@ struct reset_control *reset_control_get(
  41         int rstc_id;
  42         int ret;
  43
  44 -       if (!dev)
  45 -               return ERR_PTR(-EINVAL);
  46 -
  47         if (id)
  48 -               index = of_property_match_string(dev->of_node,
  49 +               index = of_property_match_string(node,
  50                                                  "reset-names", id);
  51 -       ret = of_parse_phandle_with_args(dev->of_node, "resets", "#reset-cells",
  52 +       ret = of_parse_phandle_with_args(node, "resets", "#reset-cells",
  53                                          index, &args);
  54         if (ret)
  55                 return ERR_PTR(ret);
  56 @@ -185,12 +183,35 @@ struct reset_control *reset_control_get(
  57                 return ERR_PTR(-ENOMEM);
  58         }
  59
  60 -       rstc->dev = dev;
  61         rstc->rcdev = rcdev;
  62         rstc->id = rstc_id;
  63
  64         return rstc;
  65  }
  66 +EXPORT_SYMBOL_GPL(of_reset_control_get);
  67 +
  68 +/**
  69 + * reset_control_get - Lookup and obtain a reference to a reset controller.
  70 + * @dev: device to be reset by the controller
  71 + * @id: reset line name
  72 + *
  73 + * Returns a struct reset_control or IS_ERR() condition containing errno.
  74 + *
  75 + * Use of id names is optional.
  76 + */
  77 +struct reset_control *reset_control_get(struct device *dev, const char *id)
  78 +{
  79 +       struct reset_control *rstc;
  80 +
  81 +       if (!dev)
  82 +               return ERR_PTR(-EINVAL);
  83 +
  84 +       rstc = of_reset_control_get(dev->of_node, id);
  85 +       if (!IS_ERR(rstc))
  86 +               rstc->dev = dev;
  87 +
  88 +       return rstc;
  89 +}
  90  EXPORT_SYMBOL_GPL(reset_control_get);
  91
  92  /**
  93 --- a/include/linux/reset.h
  94 +++ b/include/linux/reset.h
  95 @@ -1,6 +1,8 @@
  96  #ifndef _LINUX_RESET_H_
  97  #define _LINUX_RESET_H_
  98
  99 +#include <linux/of.h>
 100 +
 101  struct device;
 102  struct reset_control;
 103
 104 @@ -8,6 +10,8 @@ int reset_control_reset(struct reset_con
 105  int reset_control_assert(struct reset_control *rstc);
 106  int reset_control_deassert(struct reset_control *rstc);
 107
 108 +struct reset_control *of_reset_control_get(struct device_node *node,
 109 +                                          const char *id);
 110  struct reset_control *reset_control_get(struct device *dev, const char *id);
 111  void reset_control_put(struct reset_control *rstc);
 112  struct reset_control *devm_reset_control_get(struct device *dev, const char *id);