target/linux/apm821xx/patches-4.19/140-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 ---
   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 --- a/drivers/gpio/gpiolib-of.c
  15 +++ b/drivers/gpio/gpiolib-of.c
  16 @@ -23,6 +23,8 @@
  17  #include <linux/pinctrl/pinctrl.h>
  18  #include <linux/slab.h>
  19  #include <linux/gpio/machine.h>
  20 +#include <linux/init.h>
  21 +#include <linux/platform_device.h>
  22
  23  #include "gpiolib.h"
  24
  25 @@ -654,3 +656,72 @@ void of_gpiochip_remove(struct gpio_chip
  26         gpiochip_remove_pin_ranges(chip);
  27         of_node_put(chip->of_node);
  28  }
  29 +
  30 +#ifdef CONFIG_GPIO_SYSFS
  31 +
  32 +static struct of_device_id gpio_export_ids[] = {
  33 +       { .compatible = "gpio-export" },
  34 +       { /* sentinel */ }
  35 +};
  36 +
  37 +static int 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 +                       if (!gpio_is_valid(gpio))
  62 +                               return gpio;
  63 +
  64 +                       if (of_flags == OF_GPIO_ACTIVE_LOW)
  65 +                               flags |= GPIOF_ACTIVE_LOW;
  66 +
  67 +                       if (!of_property_read_u32(cnp, "gpio-export,output", &val))
  68 +                               flags |= val ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
  69 +                       else
  70 +                               flags |= GPIOF_IN;
  71 +
  72 +                       if (devm_gpio_request_one(&pdev->dev, gpio, flags, name ? name : of_node_full_name(np)))
  73 +                               continue;
  74 +
  75 +                       dmc = of_property_read_bool(cnp, "gpio-export,direction_may_change");
  76 +                       gpio_export_with_name(gpio, dmc, name);
  77 +                       nb++;
  78 +               }
  79 +       }
  80 +
  81 +       dev_info(&pdev->dev, "%d gpio(s) exported\n", nb);
  82 +
  83 +       return 0;
  84 +}
  85 +
  86 +static struct platform_driver gpio_export_driver = {
  87 +       .driver         = {
  88 +               .name           = "gpio-export",
  89 +               .owner  = THIS_MODULE,
  90 +               .of_match_table = of_match_ptr(gpio_export_ids),
  91 +       },
  92 +       .probe          = of_gpio_export_probe,
  93 +};
  94 +
  95 +module_platform_driver(gpio_export_driver);
  96 +
  97 +#endif
  98 --- a/include/asm-generic/gpio.h
  99 +++ b/include/asm-generic/gpio.h
 100 @@ -127,6 +127,12 @@ static inline int gpio_export(unsigned g
 101         return gpiod_export(gpio_to_desc(gpio), direction_may_change);
 102  }
 103
 104 +int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
 105 +static inline int gpio_export_with_name(unsigned gpio, bool direction_may_change, const char *name)
 106 +{
 107 +       return __gpiod_export(gpio_to_desc(gpio), direction_may_change, name);
 108 +}
 109 +
 110  static inline int gpio_export_link(struct device *dev, const char *name,
 111                                    unsigned gpio)
 112  {
 113 --- a/include/linux/gpio/consumer.h
 114 +++ b/include/linux/gpio/consumer.h
 115 @@ -533,6 +533,7 @@ struct gpio_desc *devm_fwnode_get_gpiod_
 116
 117  #if IS_ENABLED(CONFIG_GPIOLIB) && IS_ENABLED(CONFIG_GPIO_SYSFS)
 118
 119 +int _gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
 120  int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
 121  int gpiod_export_link(struct device *dev, const char *name,
 122                       struct gpio_desc *desc);
 123 @@ -540,6 +541,13 @@ void gpiod_unexport(struct gpio_desc *de
 124
 125  #else  /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
 126
 127 +static inline int _gpiod_export(struct gpio_desc *desc,
 128 +                              bool direction_may_change,
 129 +                              const char *name)
 130 +{
 131 +       return -ENOSYS;
 132 +}
 133 +
 134  static inline int gpiod_export(struct gpio_desc *desc,
 135                                bool direction_may_change)
 136  {
 137 --- a/drivers/gpio/gpiolib-sysfs.c
 138 +++ b/drivers/gpio/gpiolib-sysfs.c
 139 @@ -568,7 +568,7 @@ static struct class gpio_class = {
 140   *
 141   * Returns zero on success, else an error.
 142   */
 143 -int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 144 +int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name)
 145  {
 146         struct gpio_chip        *chip;
 147         struct gpio_device      *gdev;
 148 @@ -630,6 +630,8 @@ int gpiod_export(struct gpio_desc *desc,
 149         offset = gpio_chip_hwgpio(desc);
 150         if (chip->names && chip->names[offset])
 151                 ioname = chip->names[offset];
 152 +       if (name)
 153 +               ioname = name;
 154
 155         dev = device_create_with_groups(&gpio_class, &gdev->dev,
 156                                         MKDEV(0, 0), data, gpio_groups,
 157 @@ -651,6 +653,12 @@ err_unlock:
 158         gpiod_dbg(desc, "%s: status %d\n", __func__, status);
 159         return status;
 160  }
 161 +EXPORT_SYMBOL_GPL(__gpiod_export);
 162 +
 163 +int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 164 +{
 165 +       return __gpiod_export(desc, direction_may_change, NULL);
 166 +}
 167  EXPORT_SYMBOL_GPL(gpiod_export);
 168
 169  static int match_export(struct device *dev, const void *desc)