339 lines
10 KiB
Diff
339 lines
10 KiB
Diff
From 8f3ed1fffa35d18c2b20ebb866c71a22cc0589ff Mon Sep 17 00:00:00 2001
|
|
From: John Crispin <blogic@openwrt.org>
|
|
Date: Sun, 23 Jun 2013 00:16:22 +0200
|
|
Subject: [PATCH 29/33] owrt: 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(-)
|
|
|
|
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
|
|
index d933af3..c264748 100644
|
|
--- 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>;
|
|
+ };
|
|
+};
|
|
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
|
|
index 665f953..15ec5e5 100644
|
|
--- 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 *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);
|
|
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
|
|
index c2534d6..8697c82 100644
|
|
--- a/drivers/gpio/gpiolib.c
|
|
+++ b/drivers/gpio/gpiolib.c
|
|
@@ -96,7 +96,7 @@ static int gpiod_get_value(const struct gpio_desc *desc);
|
|
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 *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 *desc, bool direction_may_change)
|
|
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(struct gpio_chip *chip)
|
|
}
|
|
|
|
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, unsigned long flags, const char *label)
|
|
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, unsigned long flags, const char *label)
|
|
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;
|
|
}
|
|
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
|
|
index bde6469..3290572 100644
|
|
--- a/include/asm-generic/gpio.h
|
|
+++ b/include/asm-generic/gpio.h
|
|
@@ -202,7 +202,8 @@ extern void gpio_free_array(const struct gpio *array, size_t num);
|
|
* 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;
|
|
}
|
|
diff --git a/include/linux/gpio.h b/include/linux/gpio.h
|
|
index 552e3f4..07bbbcc7 100644
|
|
--- 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_cansleep(unsigned gpio, int value)
|
|
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 *dev, unsigned gpio,
|
|
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 */
|
|
--
|
|
1.7.10.4
|
|
|