target/linux/ramips/patches-3.14/0058-GPIO-add-named-gpio-exports.patch

   1 From 4b629d2e8fd9a762fd3f107c525bf2476ba7fe86 Mon Sep 17 00:00:00 2001
   2 From: John Crispin <blogic@openwrt.org>
   3 Date: Tue, 12 Aug 2014 20:49:27 +0200
   4 Subject: [PATCH] GPIO: add named gpio exports
   5
   6 Signed-off-by: John Crispin <blogic@openwrt.org>
   7 ---
   8  drivers/gpio/gpiolib-of.c     |   68 +++++++++++++++++++++++++++++++++++++++++
   9  drivers/gpio/gpiolib.c        |   11 +++++--
  10  include/asm-generic/gpio.h    |    5 +++
  11  include/linux/gpio/consumer.h |    8 +++++
  12  4 files changed, 90 insertions(+), 2 deletions(-)
  13
  14 diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
  15 index e0a98f5..f16f271 100644
  16 --- a/drivers/gpio/gpiolib-of.c
  17 +++ b/drivers/gpio/gpiolib-of.c
  18 @@ -21,6 +21,8 @@
  19  #include <linux/of_gpio.h>
  20  #include <linux/pinctrl/pinctrl.h>
  21  #include <linux/slab.h>
  22 +#include <linux/init.h>
  23 +#include <linux/platform_device.h>
  24
  25  struct gpio_desc;
  26
  27 @@ -296,3 +298,69 @@ void of_gpiochip_remove(struct gpio_chip *chip)
  28         if (chip->of_node)
  29                 of_node_put(chip->of_node);
  30  }
  31 +
  32 +static struct of_device_id gpio_export_ids[] = {
  33 +       { .compatible = "gpio-export" },
  34 +       { /* sentinel */ }
  35 +};
  36 +
  37 +static int __init of_gpio_export_probe(struct platform_device *pdev)
  38 +{
  39 +       struct device_node *np = pdev->dev.of_node;
  40 +       struct device_node *cnp;
  41 +       u32 val;
  42 +       int nb = 0;
  43 +
  44 +       for_each_child_of_node(np, cnp) {
  45 +               const char *name = NULL;
  46 +               int gpio;
  47 +               bool dmc;
  48 +               int max_gpio = 1;
  49 +               int i;
  50 +
  51 +               of_property_read_string(cnp, "gpio-export,name", &name);
  52 +
  53 +               if (!name)
  54 +                       max_gpio = of_gpio_count(cnp);
  55 +
  56 +               for (i = 0; i < max_gpio; i++) {
  57 +                       unsigned flags = 0;
  58 +                       enum of_gpio_flags of_flags;
  59 +
  60 +                       gpio = of_get_gpio_flags(cnp, i, &of_flags);
  61 +
  62 +                       if (of_flags == OF_GPIO_ACTIVE_LOW)
  63 +                               flags |= GPIOF_ACTIVE_LOW;
  64 +
  65 +                       if (!of_property_read_u32(cnp, "gpio-export,output", &val))
  66 +                               flags |= val ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
  67 +                       else
  68 +                               flags |= GPIOF_IN;
  69 +
  70 +                       if (devm_gpio_request_one(&pdev->dev, gpio, flags, name ? name : of_node_full_name(np)))
  71 +                               continue;
  72 +
  73 +                       dmc = of_property_read_bool(cnp, "gpio-export,direction_may_change");
  74 +                       gpio_export_with_name(gpio, dmc, name);
  75 +                       nb++;
  76 +               }
  77 +       }
  78 +
  79 +       dev_info(&pdev->dev, "%d gpio(s) exported\n", nb);
  80 +
  81 +       return 0;
  82 +}
  83 +
  84 +static struct platform_driver gpio_export_driver = {
  85 +       .driver         = {
  86 +               .name           = "gpio-export",
  87 +               .owner  = THIS_MODULE,
  88 +               .of_match_table = of_match_ptr(gpio_export_ids),
  89 +       },
  90 +};
  91 +
  92 +static int __init of_gpio_export_init(void)
  93 +{
  94 +       return platform_driver_probe(&gpio_export_driver, of_gpio_export_probe);
  95 +}
  96 +device_initcall(of_gpio_export_init);
  97 diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
  98 index 50c4922..aece9f1 100644
  99 --- a/drivers/gpio/gpiolib.c
 100 +++ b/drivers/gpio/gpiolib.c
 101 @@ -803,7 +803,7 @@ static struct class gpio_class = {
 102   *
 103   * Returns zero on success, else an error.
 104   */
 105 -int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 106 +int _gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name)
 107  {
 108         unsigned long           flags;
 109         int                     status;
 110 @@ -843,7 +843,8 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 111         offset = gpio_chip_hwgpio(desc);
 112         if (desc->chip->names && desc->chip->names[offset])
 113                 ioname = desc->chip->names[offset];
 114 -
 115 +       if (name)
 116 +               ioname = name;
 117         dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0),
 118                             desc, ioname ? ioname : "gpio%u",
 119                             desc_to_gpio(desc));
 120 @@ -880,6 +881,12 @@ fail_unlock:
 121         gpiod_dbg(desc, "%s: status %d\n", __func__, status);
 122         return status;
 123  }
 124 +EXPORT_SYMBOL_GPL(_gpiod_export);
 125 +
 126 +int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 127 +{
 128 +       return _gpiod_export(desc, direction_may_change, NULL);
 129 +}
 130  EXPORT_SYMBOL_GPL(gpiod_export);
 131
 132  static int match_export(struct device *dev, const void *data)
 133 diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
 134 index a5f56a0..70a32ee 100644
 135 --- a/include/asm-generic/gpio.h
 136 +++ b/include/asm-generic/gpio.h
 137 @@ -126,6 +126,11 @@ static inline int gpio_export(unsigned gpio, bool direction_may_change)
 138         return gpiod_export(gpio_to_desc(gpio), direction_may_change);
 139  }
 140
 141 +static inline int gpio_export_with_name(unsigned gpio, bool direction_may_change, const char *name)
 142 +{
 143 +       return _gpiod_export(gpio_to_desc(gpio), direction_may_change, name);
 144 +}
 145 +
 146  static inline int gpio_export_link(struct device *dev, const char *name,
 147                                    unsigned gpio)
 148  {
 149 diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
 150 index 7a8144f..085c31c 100644
 151 --- a/include/linux/gpio/consumer.h
 152 +++ b/include/linux/gpio/consumer.h
 153 @@ -219,6 +219,7 @@ static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
 154
 155  #if IS_ENABLED(CONFIG_GPIOLIB) && IS_ENABLED(CONFIG_GPIO_SYSFS)
 156
 157 +int _gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
 158  int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
 159  int gpiod_export_link(struct device *dev, const char *name,
 160                       struct gpio_desc *desc);
 161 @@ -227,6 +228,13 @@ void gpiod_unexport(struct gpio_desc *desc);
 162
 163  #else  /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
 164
 165 +static inline int _gpiod_export(struct gpio_desc *desc,
 166 +                              bool direction_may_change,
 167 +                              const char *name)
 168 +{
 169 +       return -ENOSYS;
 170 +}
 171 +
 172  static inline int gpiod_export(struct gpio_desc *desc,
 173                                bool direction_may_change)
 174  {
 175 --
 176 1.7.10.4
 177