target/linux/generic/patches-4.4/083-0001-clk-Add-devm_-clk_hw_-register-unregister-APIs.patch

   1 From 4143804c4fdef40358c654d1fb2271a1a0f1fedf Mon Sep 17 00:00:00 2001
   2 From: Stephen Boyd <sboyd@codeaurora.org>
   3 Date: Fri, 5 Feb 2016 17:02:52 -0800
   4 Subject: [PATCH] clk: Add {devm_}clk_hw_{register,unregister}() APIs
   5
   6 We've largely split the clk consumer and provider APIs along
   7 struct clk and struct clk_hw, but clk_register() still returns a
   8 struct clk pointer for each struct clk_hw that's registered.
   9 Eventually we'd like to only allocate struct clks when there's a
  10 user, because struct clk is per-user now, so clk_register() needs
  11 to change.
  12
  13 Let's add new APIs to register struct clk_hws, but this time
  14 we'll hide the struct clk from the caller by returning an int
  15 error code. Also add an unregistration API that takes the clk_hw
  16 structure that was passed to the registration API. This way
  17 provider drivers never have to deal with a struct clk pointer
  18 unless they're using the clk consumer APIs.
  19
  20 Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
  21 ---
  22  Documentation/driver-model/devres.txt |  1 +
  23  drivers/clk/clk.c                     | 86 +++++++++++++++++++++++++++++++++++
  24  include/linux/clk-provider.h          |  6 +++
  25  3 files changed, 93 insertions(+)
  26
  27 --- a/Documentation/driver-model/devres.txt
  28 +++ b/Documentation/driver-model/devres.txt
  29 @@ -236,6 +236,7 @@ certainly invest a bit more effort into
  30  CLOCK
  31    devm_clk_get()
  32    devm_clk_put()
  33 +  devm_clk_hw_register()
  34
  35  DMA
  36    dmam_alloc_coherent()
  37 --- a/drivers/clk/clk.c
  38 +++ b/drivers/clk/clk.c
  39 @@ -2595,6 +2595,22 @@ fail_out:
  40  }
  41  EXPORT_SYMBOL_GPL(clk_register);
  42
  43 +/**
  44 + * clk_hw_register - register a clk_hw and return an error code
  45 + * @dev: device that is registering this clock
  46 + * @hw: link to hardware-specific clock data
  47 + *
  48 + * clk_hw_register is the primary interface for populating the clock tree with
  49 + * new clock nodes. It returns an integer equal to zero indicating success or
  50 + * less than zero indicating failure. Drivers must test for an error code after
  51 + * calling clk_hw_register().
  52 + */
  53 +int clk_hw_register(struct device *dev, struct clk_hw *hw)
  54 +{
  55 +       return PTR_ERR_OR_ZERO(clk_register(dev, hw));
  56 +}
  57 +EXPORT_SYMBOL_GPL(clk_hw_register);
  58 +
  59  /* Free memory allocated for a clock. */
  60  static void __clk_release(struct kref *ref)
  61  {
  62 @@ -2696,11 +2712,26 @@ void clk_unregister(struct clk *clk)
  63  }
  64  EXPORT_SYMBOL_GPL(clk_unregister);
  65
  66 +/**
  67 + * clk_hw_unregister - unregister a currently registered clk_hw
  68 + * @hw: hardware-specific clock data to unregister
  69 + */
  70 +void clk_hw_unregister(struct clk_hw *hw)
  71 +{
  72 +       clk_unregister(hw->clk);
  73 +}
  74 +EXPORT_SYMBOL_GPL(clk_hw_unregister);
  75 +
  76  static void devm_clk_release(struct device *dev, void *res)
  77  {
  78         clk_unregister(*(struct clk **)res);
  79  }
  80
  81 +static void devm_clk_hw_release(struct device *dev, void *res)
  82 +{
  83 +       clk_hw_unregister(*(struct clk_hw **)res);
  84 +}
  85 +
  86  /**
  87   * devm_clk_register - resource managed clk_register()
  88   * @dev: device that is registering this clock
  89 @@ -2731,6 +2762,36 @@ struct clk *devm_clk_register(struct dev
  90  }
  91  EXPORT_SYMBOL_GPL(devm_clk_register);
  92
  93 +/**
  94 + * devm_clk_hw_register - resource managed clk_hw_register()
  95 + * @dev: device that is registering this clock
  96 + * @hw: link to hardware-specific clock data
  97 + *
  98 + * Managed clk_hw_register(). Clocks returned from this function are
  99 + * automatically clk_hw_unregister()ed on driver detach. See clk_hw_register()
 100 + * for more information.
 101 + */
 102 +int devm_clk_hw_register(struct device *dev, struct clk_hw *hw)
 103 +{
 104 +       struct clk_hw **hwp;
 105 +       int ret;
 106 +
 107 +       hwp = devres_alloc(devm_clk_hw_release, sizeof(*hwp), GFP_KERNEL);
 108 +       if (!hwp)
 109 +               return -ENOMEM;
 110 +
 111 +       ret = clk_hw_register(dev, hw);
 112 +       if (!ret) {
 113 +               *hwp = hw;
 114 +               devres_add(dev, hwp);
 115 +       } else {
 116 +               devres_free(hwp);
 117 +       }
 118 +
 119 +       return ret;
 120 +}
 121 +EXPORT_SYMBOL_GPL(devm_clk_hw_register);
 122 +
 123  static int devm_clk_match(struct device *dev, void *res, void *data)
 124  {
 125         struct clk *c = res;
 126 @@ -2739,6 +2800,15 @@ static int devm_clk_match(struct device
 127         return c == data;
 128  }
 129
 130 +static int devm_clk_hw_match(struct device *dev, void *res, void *data)
 131 +{
 132 +       struct clk_hw *hw = res;
 133 +
 134 +       if (WARN_ON(!hw))
 135 +               return 0;
 136 +       return hw == data;
 137 +}
 138 +
 139  /**
 140   * devm_clk_unregister - resource managed clk_unregister()
 141   * @clk: clock to unregister
 142 @@ -2753,6 +2823,22 @@ void devm_clk_unregister(struct device *
 143  }
 144  EXPORT_SYMBOL_GPL(devm_clk_unregister);
 145
 146 +/**
 147 + * devm_clk_hw_unregister - resource managed clk_hw_unregister()
 148 + * @dev: device that is unregistering the hardware-specific clock data
 149 + * @hw: link to hardware-specific clock data
 150 + *
 151 + * Unregister a clk_hw registered with devm_clk_hw_register(). Normally
 152 + * this function will not need to be called and the resource management
 153 + * code will ensure that the resource is freed.
 154 + */
 155 +void devm_clk_hw_unregister(struct device *dev, struct clk_hw *hw)
 156 +{
 157 +       WARN_ON(devres_release(dev, devm_clk_hw_release, devm_clk_hw_match,
 158 +                               hw));
 159 +}
 160 +EXPORT_SYMBOL_GPL(devm_clk_hw_unregister);
 161 +
 162  /*
 163   * clkdev helpers
 164   */
 165 --- a/include/linux/clk-provider.h
 166 +++ b/include/linux/clk-provider.h
 167 @@ -639,9 +639,15 @@ void of_gpio_mux_clk_setup(struct device
 168  struct clk *clk_register(struct device *dev, struct clk_hw *hw);
 169  struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw);
 170
 171 +int __must_check clk_hw_register(struct device *dev, struct clk_hw *hw);
 172 +int __must_check devm_clk_hw_register(struct device *dev, struct clk_hw *hw);
 173 +
 174  void clk_unregister(struct clk *clk);
 175  void devm_clk_unregister(struct device *dev, struct clk *clk);
 176
 177 +void clk_hw_unregister(struct clk_hw *hw);
 178 +void devm_clk_hw_unregister(struct device *dev, struct clk_hw *hw);
 179 +
 180  /* helper functions */
 181  const char *__clk_get_name(const struct clk *clk);
 182  const char *clk_hw_get_name(const struct clk_hw *hw);