target/linux/generic/hack-6.1/800-GPIO-add-named-gpio-exports.patch

   1 From cc809a441d8f2924f785eb863dfa6aef47a25b0b 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 30/36] GPIO: add named gpio exports
   5
   6 Signed-off-by: John Crispin <blogic@openwrt.org>
   7 --- a/drivers/gpio/gpiolib-of.c
   8 +++ b/drivers/gpio/gpiolib-of.c
   9 @@ -19,6 +19,8 @@
  10  #include <linux/pinctrl/pinctrl.h>
  11  #include <linux/slab.h>
  12  #include <linux/gpio/machine.h>
  13 +#include <linux/init.h>
  14 +#include <linux/platform_device.h>
  15
  16  #include "gpiolib.h"
  17  #include "gpiolib-of.h"
  18 @@ -1030,3 +1032,100 @@ void of_gpio_dev_init(struct gpio_chip *
  19         else
  20                 gc->of_node = gdev->dev.of_node;
  21  }
  22 +
  23 +#ifdef CONFIG_GPIO_SYSFS
  24 +
  25 +static struct of_device_id gpio_export_ids[] = {
  26 +       { .compatible = "gpio-export" },
  27 +       { /* sentinel */ }
  28 +};
  29 +
  30 +static int of_gpio_export_probe(struct platform_device *pdev)
  31 +{
  32 +       struct device_node *np = pdev->dev.of_node;
  33 +       struct device_node *cnp;
  34 +       u32 val;
  35 +       int nb = 0;
  36 +
  37 +       for_each_child_of_node(np, cnp) {
  38 +               const char *name = NULL;
  39 +               int gpio;
  40 +               bool dmc;
  41 +               int max_gpio = 1;
  42 +               int i;
  43 +
  44 +               of_property_read_string(cnp, "gpio-export,name", &name);
  45 +
  46 +               if (!name)
  47 +                       max_gpio = of_gpio_count(cnp);
  48 +
  49 +               for (i = 0; i < max_gpio; i++) {
  50 +                       struct gpio_desc *desc;
  51 +                       unsigned flags = 0;
  52 +                       enum of_gpio_flags of_flags;
  53 +
  54 +                       gpio = of_get_gpio_flags(cnp, i, &of_flags);
  55 +                       if (!gpio_is_valid(gpio))
  56 +                               return gpio;
  57 +
  58 +                       if (of_flags & OF_GPIO_ACTIVE_LOW)
  59 +                               flags |= GPIOF_ACTIVE_LOW;
  60 +
  61 +                       if (!of_property_read_u32(cnp, "gpio-export,output", &val)) {
  62 +                               if (of_flags & OF_GPIO_SINGLE_ENDED) {
  63 +                                       /*
  64 +                                        * As gpiod_direction_output_raw() is used, we
  65 +                                        * need to emulate open drain or open source here.
  66 +                                        */
  67 +                                       if (of_flags & OF_GPIO_OPEN_DRAIN) {
  68 +                                               flags |= GPIOF_OPEN_DRAIN;
  69 +                                               flags |= val ? GPIOF_IN : GPIOF_OUT_INIT_LOW;
  70 +                                       } else {
  71 +                                               flags |= GPIOF_OPEN_SOURCE;
  72 +                                               flags |= val ? GPIOF_OUT_INIT_HIGH : GPIOF_IN;
  73 +                                       }
  74 +                               } else {
  75 +                                       flags |= val ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
  76 +                               }
  77 +                       } else {
  78 +                               flags |= GPIOF_IN;
  79 +                       }
  80 +
  81 +                       if (devm_gpio_request_one(&pdev->dev, gpio, flags, name ? name : of_node_full_name(np)))
  82 +                               continue;
  83 +
  84 +                       /*
  85 +                        * When emulating open-source or open-drain functionalities by not
  86 +                        * actively driving the line (setting mode to input) we still need to
  87 +                        * set the IS_OUT flag or otherwise we won't be able to set the line
  88 +                        * value anymore.
  89 +                        */
  90 +                       if ((flags & GPIOF_IN) &&
  91 +                           ((flags & GPIOF_OPEN_DRAIN) || (flags & GPIOF_OPEN_SOURCE))) {
  92 +                               desc = gpio_to_desc(gpio);
  93 +                               set_bit(FLAG_IS_OUT, &desc->flags);
  94 +                       }
  95 +
  96 +                       dmc = of_property_read_bool(cnp, "gpio-export,direction_may_change");
  97 +                       gpio_export_with_name(gpio, dmc, name);
  98 +                       nb++;
  99 +               }
 100 +       }
 101 +
 102 +       dev_info(&pdev->dev, "%d gpio(s) exported\n", nb);
 103 +
 104 +       return 0;
 105 +}
 106 +
 107 +static struct platform_driver gpio_export_driver = {
 108 +       .driver         = {
 109 +               .name           = "gpio-export",
 110 +               .owner  = THIS_MODULE,
 111 +               .of_match_table = of_match_ptr(gpio_export_ids),
 112 +       },
 113 +       .probe          = of_gpio_export_probe,
 114 +};
 115 +
 116 +module_platform_driver(gpio_export_driver);
 117 +
 118 +#endif
 119 --- a/include/asm-generic/gpio.h
 120 +++ b/include/asm-generic/gpio.h
 121 @@ -125,6 +125,12 @@ static inline int gpio_export(unsigned g
 122         return gpiod_export(gpio_to_desc(gpio), direction_may_change);
 123  }
 124
 125 +int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
 126 +static inline int gpio_export_with_name(unsigned gpio, bool direction_may_change, const char *name)
 127 +{
 128 +       return __gpiod_export(gpio_to_desc(gpio), direction_may_change, name);
 129 +}
 130 +
 131  static inline int gpio_export_link(struct device *dev, const char *name,
 132                                    unsigned gpio)
 133  {
 134 --- a/include/linux/gpio/consumer.h
 135 +++ b/include/linux/gpio/consumer.h
 136 @@ -715,6 +715,7 @@ static inline struct gpio_desc *acpi_get
 137
 138  #if IS_ENABLED(CONFIG_GPIOLIB) && IS_ENABLED(CONFIG_GPIO_SYSFS)
 139
 140 +int _gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
 141  int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
 142  int gpiod_export_link(struct device *dev, const char *name,
 143                       struct gpio_desc *desc);
 144 @@ -722,6 +723,13 @@ void gpiod_unexport(struct gpio_desc *de
 145
 146  #else  /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
 147
 148 +static inline int _gpiod_export(struct gpio_desc *desc,
 149 +                              bool direction_may_change,
 150 +                              const char *name)
 151 +{
 152 +       return -ENOSYS;
 153 +}
 154 +
 155  static inline int gpiod_export(struct gpio_desc *desc,
 156                                bool direction_may_change)
 157  {
 158 --- a/drivers/gpio/gpiolib-sysfs.c
 159 +++ b/drivers/gpio/gpiolib-sysfs.c
 160 @@ -544,7 +544,7 @@ static struct class gpio_class = {
 161   *
 162   * Returns zero on success, else an error.
 163   */
 164 -int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 165 +int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name)
 166  {
 167         struct gpio_chip        *chip;
 168         struct gpio_device      *gdev;
 169 @@ -606,6 +606,8 @@ int gpiod_export(struct gpio_desc *desc,
 170         offset = gpio_chip_hwgpio(desc);
 171         if (chip->names && chip->names[offset])
 172                 ioname = chip->names[offset];
 173 +       if (name)
 174 +               ioname = name;
 175
 176         dev = device_create_with_groups(&gpio_class, &gdev->dev,
 177                                         MKDEV(0, 0), data, gpio_groups,
 178 @@ -627,6 +629,12 @@ err_unlock:
 179         gpiod_dbg(desc, "%s: status %d\n", __func__, status);
 180         return status;
 181  }
 182 +EXPORT_SYMBOL_GPL(__gpiod_export);
 183 +
 184 +int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 185 +{
 186 +       return __gpiod_export(desc, direction_may_change, NULL);
 187 +}
 188  EXPORT_SYMBOL_GPL(gpiod_export);
 189
 190  static int match_export(struct device *dev, const void *desc)