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From cc809a441d8f2924f785eb863dfa6aef47a25b0b Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Tue, 12 Aug 2014 20:49:27 +0200
Subject: [PATCH 30/36] GPIO: add named gpio exports
Signed-off-by: John Crispin <blogic@openwrt.org>
---
drivers/gpio/gpiolib-of.c | 68 +++++++++++++++++++++++++++++++++++++++++
drivers/gpio/gpiolib.c | 11 +++++--
include/asm-generic/gpio.h | 5 +++
include/linux/gpio/consumer.h | 8 +++++
4 files changed, 90 insertions(+), 2 deletions(-)
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -23,6 +23,8 @@
#include <linux/pinctrl/pinctrl.h>
#include <linux/slab.h>
#include <linux/gpio/machine.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
#include "gpiolib.h"
@@ -450,3 +452,73 @@ void of_gpiochip_remove(struct gpio_chip
gpiochip_remove_pin_ranges(chip);
of_node_put(chip->of_node);
}
+
+#ifdef CONFIG_GPIO_SYSFS
+
+static struct of_device_id gpio_export_ids[] = {
+ { .compatible = "gpio-export" },
+ { /* sentinel */ }
+};
+
+static int __init of_gpio_export_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *cnp;
+ u32 val;
+ int nb = 0;
+
+ for_each_child_of_node(np, cnp) {
+ const char *name = NULL;
+ int gpio;
+ bool dmc;
+ int max_gpio = 1;
+ int i;
+
+ of_property_read_string(cnp, "gpio-export,name", &name);
+
+ if (!name)
+ max_gpio = of_gpio_count(cnp);
+
+ for (i = 0; i < max_gpio; i++) {
+ unsigned flags = 0;
+ enum of_gpio_flags of_flags;
+
+ gpio = of_get_gpio_flags(cnp, i, &of_flags);
+
+ if (of_flags == OF_GPIO_ACTIVE_LOW)
+ flags |= GPIOF_ACTIVE_LOW;
+
+ if (!of_property_read_u32(cnp, "gpio-export,output", &val))
+ flags |= val ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
+ else
+ flags |= GPIOF_IN;
+
+ if (devm_gpio_request_one(&pdev->dev, gpio, flags, name ? name : of_node_full_name(np)))
+ continue;
+
+ dmc = of_property_read_bool(cnp, "gpio-export,direction_may_change");
+ gpio_export_with_name(gpio, dmc, name);
+ nb++;
+ }
+ }
+
+ dev_info(&pdev->dev, "%d gpio(s) exported\n", nb);
+
+ return 0;
+}
+
+static struct platform_driver gpio_export_driver = {
+ .driver = {
+ .name = "gpio-export",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(gpio_export_ids),
+ },
+};
+
+static int __init of_gpio_export_init(void)
+{
+ return platform_driver_probe(&gpio_export_driver, of_gpio_export_probe);
+}
+device_initcall(of_gpio_export_init);
+
+#endif
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -122,6 +122,12 @@ static inline int gpio_export(unsigned g
return gpiod_export(gpio_to_desc(gpio), direction_may_change);
}
+int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
+static inline int gpio_export_with_name(unsigned gpio, bool direction_may_change, const char *name)
+{
+ return __gpiod_export(gpio_to_desc(gpio), direction_may_change, name);
+}
+
static inline int gpio_export_link(struct device *dev, const char *name,
unsigned gpio)
{
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -427,6 +427,7 @@ static inline struct gpio_desc *devm_get
#if IS_ENABLED(CONFIG_GPIOLIB) && IS_ENABLED(CONFIG_GPIO_SYSFS)
+int _gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
int gpiod_export_link(struct device *dev, const char *name,
struct gpio_desc *desc);
@@ -434,6 +435,13 @@ void gpiod_unexport(struct gpio_desc *de
#else /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
+static inline int _gpiod_export(struct gpio_desc *desc,
+ bool direction_may_change,
+ const char *name)
+{
+ return -ENOSYS;
+}
+
static inline int gpiod_export(struct gpio_desc *desc,
bool direction_may_change)
{
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -544,7 +544,7 @@ static struct class gpio_class = {
*
* Returns zero on success, else an error.
*/
-int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
+int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name)
{
struct gpio_chip *chip;
struct gpiod_data *data;
@@ -604,6 +604,8 @@ int gpiod_export(struct gpio_desc *desc,
offset = gpio_chip_hwgpio(desc);
if (chip->names && chip->names[offset])
ioname = chip->names[offset];
+ if (name)
+ ioname = name;
dev = device_create_with_groups(&gpio_class, chip->dev,
MKDEV(0, 0), data, gpio_groups,
@@ -625,6 +627,12 @@ err_unlock:
gpiod_dbg(desc, "%s: status %d\n", __func__, status);
return status;
}
+EXPORT_SYMBOL_GPL(__gpiod_export);
+
+int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
+{
+ return __gpiod_export(desc, direction_may_change, NULL);
+}
EXPORT_SYMBOL_GPL(gpiod_export);
static int match_export(struct device *dev, const void *desc)
|
