+++ /dev/null
-From def7e226d3e5c501180bdc2fc644ff924b5a275e Mon Sep 17 00:00:00 2001
-From: John Crispin <blogic@openwrt.org>
-Date: Sun, 23 Jun 2013 00:16:22 +0200
-Subject: [PATCH 132/133] GPIO: add gpio_export_with_name
-
-http://lists.infradead.org/pipermail/linux-arm-kernel/2012-November/133856.html
-
-Signed-off-by: John Crispin <blogic@openwrt.org>
----
- Documentation/devicetree/bindings/gpio/gpio.txt | 60 ++++++++++++++++++++
- drivers/gpio/gpiolib-of.c | 68 +++++++++++++++++++++++
- drivers/gpio/gpiolib.c | 24 +++++---
- include/asm-generic/gpio.h | 6 +-
- include/linux/gpio.h | 26 ++++++++-
- 5 files changed, 172 insertions(+), 12 deletions(-)
-
---- a/Documentation/devicetree/bindings/gpio/gpio.txt
-+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
-@@ -112,3 +112,63 @@ where,
-
- The pinctrl node must have "#gpio-range-cells" property to show number of
- arguments to pass with phandle from gpio controllers node.
-+
-+3) gpio-export
-+--------------
-+
-+gpio-export will allow you to automatically export gpio
-+
-+required properties:
-+- compatible: Should be "gpio-export"
-+
-+in each child node will reprensent a gpio or if no name is specified
-+a list of gpio to export
-+
-+required properties:
-+- gpios: gpio to export
-+
-+optional properties:
-+ - gpio-export,name: export name
-+ - gpio-export,output: to set the as output with default value
-+ if no present gpio as input
-+ - pio-export,direction_may_change: boolean to allow the direction to be controllable
-+
-+Example:
-+
-+
-+gpio_export {
-+ compatible = "gpio-export";
-+ #size-cells = <0>;
-+
-+ in {
-+ gpio-export,name = "in";
-+ gpios = <&pioC 20 0>;
-+ };
-+
-+ out {
-+ gpio-export,name = "out";
-+ gpio-export,output = <1>;
-+ gpio-export,direction_may_change;
-+ gpios = <&pioC 21 0>;
-+ };
-+
-+ in_out {
-+ gpio-export,name = "in_out";
-+ gpio-export,direction_may_change;
-+ gpios = <&pioC 21 0>;
-+ };
-+
-+ gpios_in {
-+ gpios = <&pioB 0 0
-+ &pioB 3 0
-+ &pioC 4 0>;
-+ gpio-export,direction_may_change;
-+ };
-+
-+ gpios_out {
-+ gpios = <&pioB 1 0
-+ &pioB 2 0
-+ &pioC 3 0>;
-+ gpio-export,output = <1>;
-+ };
-+};
---- a/drivers/gpio/gpiolib-of.c
-+++ b/drivers/gpio/gpiolib-of.c
-@@ -21,6 +21,8 @@
- #include <linux/of_gpio.h>
- #include <linux/pinctrl/pinctrl.h>
- #include <linux/slab.h>
-+#include <linux/init.h>
-+#include <linux/platform_device.h>
-
- /* Private data structure for of_gpiochip_find_and_xlate */
- struct gg_data {
-@@ -242,3 +244,69 @@ void of_gpiochip_remove(struct gpio_chip
- if (chip->of_node)
- of_node_put(chip->of_node);
- }
-+
-+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);
---- a/drivers/gpio/gpiolib.c
-+++ b/drivers/gpio/gpiolib.c
-@@ -96,7 +96,7 @@ static int gpiod_get_value(const struct
- static void gpiod_set_value(struct gpio_desc *desc, int value);
- static int gpiod_cansleep(const struct gpio_desc *desc);
- static int gpiod_to_irq(const struct gpio_desc *desc);
--static int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
-+static int gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
- static int gpiod_export_link(struct device *dev, const char *name,
- struct gpio_desc *desc);
- static int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value);
-@@ -674,7 +674,7 @@ static ssize_t export_store(struct class
- status = -ENODEV;
- goto done;
- }
-- status = gpiod_export(desc, true);
-+ status = gpiod_export(desc, true, NULL);
- if (status < 0)
- gpiod_free(desc);
- else
-@@ -736,9 +736,10 @@ static struct class gpio_class = {
-
-
- /**
-- * gpio_export - export a GPIO through sysfs
-+ * gpio_export_with_name - export a GPIO through sysfs
- * @gpio: gpio to make available, already requested
- * @direction_may_change: true if userspace may change gpio direction
-+ * @name: gpio name
- * Context: arch_initcall or later
- *
- * When drivers want to make a GPIO accessible to userspace after they
-@@ -750,7 +751,7 @@ static struct class gpio_class = {
- *
- * Returns zero on success, else an error.
- */
--static int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
-+static int gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name)
- {
- unsigned long flags;
- int status;
-@@ -783,6 +784,8 @@ static int gpiod_export(struct gpio_desc
- goto fail_unlock;
- }
-
-+ if (name)
-+ ioname = name;
- if (!desc->chip->direction_input || !desc->chip->direction_output)
- direction_may_change = false;
- spin_unlock_irqrestore(&gpio_lock, flags);
-@@ -829,11 +832,11 @@ fail_unlock:
- return status;
- }
-
--int gpio_export(unsigned gpio, bool direction_may_change)
-+int gpio_export_with_name(unsigned gpio, bool direction_may_change, const char *name)
- {
-- return gpiod_export(gpio_to_desc(gpio), direction_may_change);
-+ return gpiod_export(gpio_to_desc(gpio), direction_may_change, name);
- }
--EXPORT_SYMBOL_GPL(gpio_export);
-+EXPORT_SYMBOL_GPL(gpio_export_with_name);
-
- static int match_export(struct device *dev, const void *data)
- {
-@@ -1092,7 +1095,7 @@ static inline void gpiochip_unexport(str
- }
-
- static inline int gpiod_export(struct gpio_desc *desc,
-- bool direction_may_change)
-+ bool direction_may_change, const char *name)
- {
- return -ENOSYS;
- }
-@@ -1521,6 +1524,9 @@ int gpio_request_one(unsigned gpio, unsi
- if (flags & GPIOF_OPEN_SOURCE)
- set_bit(FLAG_OPEN_SOURCE, &desc->flags);
-
-+ if (flags & GPIOF_ACTIVE_LOW)
-+ set_bit(FLAG_ACTIVE_LOW, &gpio_desc[gpio].flags);
-+
- if (flags & GPIOF_DIR_IN)
- err = gpiod_direction_input(desc);
- else
-@@ -1531,7 +1537,7 @@ int gpio_request_one(unsigned gpio, unsi
- goto free_gpio;
-
- if (flags & GPIOF_EXPORT) {
-- err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE);
-+ err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE, NULL);
- if (err)
- goto free_gpio;
- }
---- a/include/asm-generic/gpio.h
-+++ b/include/asm-generic/gpio.h
-@@ -202,7 +202,8 @@ extern void gpio_free_array(const struct
- * A sysfs interface can be exported by individual drivers if they want,
- * but more typically is configured entirely from userspace.
- */
--extern int gpio_export(unsigned gpio, bool direction_may_change);
-+extern int gpio_export_with_name(unsigned gpio, bool direction_may_change,
-+ const char *name);
- extern int gpio_export_link(struct device *dev, const char *name,
- unsigned gpio);
- extern int gpio_sysfs_set_active_low(unsigned gpio, int value);
-@@ -284,7 +285,8 @@ struct device;
-
- /* sysfs support is only available with gpiolib, where it's optional */
-
--static inline int gpio_export(unsigned gpio, bool direction_may_change)
-+static inline int gpio_export_with_name(unsigned gpio,
-+ bool direction_may_change, const char *name)
- {
- return -ENOSYS;
- }
---- a/include/linux/gpio.h
-+++ b/include/linux/gpio.h
-@@ -27,6 +27,9 @@
- #define GPIOF_EXPORT_DIR_FIXED (GPIOF_EXPORT)
- #define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
-
-+#define GPIOF_ACTIVE_LOW (1 << 6)
-+
-+
- /**
- * struct gpio - a structure describing a GPIO with configuration
- * @gpio: the GPIO number
-@@ -169,7 +172,8 @@ static inline void gpio_set_value_cansle
- WARN_ON(1);
- }
-
--static inline int gpio_export(unsigned gpio, bool direction_may_change)
-+static inline int gpio_export_with_name(unsigned gpio,
-+ bool direction_may_change, const char *name)
- {
- /* GPIO can never have been requested or set as {in,out}put */
- WARN_ON(1);
-@@ -236,4 +240,24 @@ int devm_gpio_request_one(struct device
- unsigned long flags, const char *label);
- void devm_gpio_free(struct device *dev, unsigned int gpio);
-
-+/**
-+ * gpio_export - export a GPIO through sysfs
-+ * @gpio: gpio to make available, already requested
-+ * @direction_may_change: true if userspace may change gpio direction
-+ * Context: arch_initcall or later
-+ *
-+ * When drivers want to make a GPIO accessible to userspace after they
-+ * have requested it -- perhaps while debugging, or as part of their
-+ * public interface -- they may use this routine. If the GPIO can
-+ * change direction (some can't) and the caller allows it, userspace
-+ * will see "direction" sysfs attribute which may be used to change
-+ * the gpio's direction. A "value" attribute will always be provided.
-+ *
-+ * Returns zero on success, else an error.
-+ */
-+static inline int gpio_export(unsigned gpio,bool direction_may_change)
-+{
-+ return gpio_export_with_name(gpio, direction_may_change, NULL);
-+}
-+
- #endif /* __LINUX_GPIO_H */
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