1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/gpio/devres.c b/drivers/gpio/devres.c
new file mode 100644
index 00000000000..65978cf85f7
--- /dev/null
+++ b/drivers/gpio/devres.c
@@ -0,0 +1,247 @@
+/*
+ * drivers/gpio/devres.c - managed gpio resources
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * This file is based on kernel/irq/devres.c
+ *
+ * Copyright (c) 2011 John Crispin <blogic@openwrt.org>
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/device.h>
+#include <linux/gfp.h>
+
+static void devm_gpiod_release(struct device *dev, void *res)
+{
+	struct gpio_desc **desc = res;
+
+	gpiod_put(*desc);
+}
+
+static int devm_gpiod_match(struct device *dev, void *res, void *data)
+{
+	struct gpio_desc **this = res, **gpio = data;
+
+	return *this == *gpio;
+}
+
+/**
+ * devm_gpiod_get - Resource-managed gpiod_get()
+ * @dev:	GPIO consumer
+ * @con_id:	function within the GPIO consumer
+ *
+ * Managed gpiod_get(). GPIO descriptors returned from this function are
+ * automatically disposed on driver detach. See gpiod_get() for detailed
+ * information about behavior and return values.
+ */
+struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
+					      const char *con_id)
+{
+	return devm_gpiod_get_index(dev, con_id, 0);
+}
+EXPORT_SYMBOL(devm_gpiod_get);
+
+/**
+ * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ *
+ * Managed gpiod_get_optional(). GPIO descriptors returned from this function
+ * are automatically disposed on driver detach. See gpiod_get_optional() for
+ * detailed information about behavior and return values.
+ */
+struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
+						       const char *con_id)
+{
+	return devm_gpiod_get_index_optional(dev, con_id, 0);
+}
+EXPORT_SYMBOL(devm_gpiod_get_optional);
+
+/**
+ * devm_gpiod_get_index - Resource-managed gpiod_get_index()
+ * @dev:	GPIO consumer
+ * @con_id:	function within the GPIO consumer
+ * @idx:	index of the GPIO to obtain in the consumer
+ *
+ * Managed gpiod_get_index(). GPIO descriptors returned from this function are
+ * automatically disposed on driver detach. See gpiod_get_index() for detailed
+ * information about behavior and return values.
+ */
+struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
+						    const char *con_id,
+						    unsigned int idx)
+{
+	struct gpio_desc **dr;
+	struct gpio_desc *desc;
+
+	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpiod_desc *),
+			  GFP_KERNEL);
+	if (!dr)
+		return ERR_PTR(-ENOMEM);
+
+	desc = gpiod_get_index(dev, con_id, idx);
+	if (IS_ERR(desc)) {
+		devres_free(dr);
+		return desc;
+	}
+
+	*dr = desc;
+	devres_add(dev, dr);
+
+	return desc;
+}
+EXPORT_SYMBOL(devm_gpiod_get_index);
+
+/**
+ * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @index: index of the GPIO to obtain in the consumer
+ *
+ * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
+ * function are automatically disposed on driver detach. See
+ * gpiod_get_index_optional() for detailed information about behavior and
+ * return values.
+ */
+struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
+							     const char *con_id,
+							     unsigned int index)
+{
+	struct gpio_desc *desc;
+
+	desc = devm_gpiod_get_index(dev, con_id, index);
+	if (IS_ERR(desc)) {
+		if (PTR_ERR(desc) == -ENOENT)
+			return NULL;
+	}
+
+	return desc;
+}
+EXPORT_SYMBOL(devm_gpiod_get_index_optional);
+
+/**
+ * devm_gpiod_put - Resource-managed gpiod_put()
+ * @desc:	GPIO descriptor to dispose of
+ *
+ * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
+ * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
+ * will be disposed of by the resource management code.
+ */
+void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
+{
+	WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
+		&desc));
+}
+EXPORT_SYMBOL(devm_gpiod_put);
+
+
+
+
+static void devm_gpio_release(struct device *dev, void *res)
+{
+	unsigned *gpio = res;
+
+	gpio_free(*gpio);
+}
+
+static int devm_gpio_match(struct device *dev, void *res, void *data)
+{
+	unsigned *this = res, *gpio = data;
+
+	return *this == *gpio;
+}
+
+/**
+ *      devm_gpio_request - request a GPIO for a managed device
+ *      @dev: device to request the GPIO for
+ *      @gpio: GPIO to allocate
+ *      @label: the name of the requested GPIO
+ *
+ *      Except for the extra @dev argument, this function takes the
+ *      same arguments and performs the same function as
+ *      gpio_request().  GPIOs requested with this function will be
+ *      automatically freed on driver detach.
+ *
+ *      If an GPIO allocated with this function needs to be freed
+ *      separately, devm_gpio_free() must be used.
+ */
+
+int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
+{
+	unsigned *dr;
+	int rc;
+
+	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
+	if (!dr)
+		return -ENOMEM;
+
+	rc = gpio_request(gpio, label);
+	if (rc) {
+		devres_free(dr);
+		return rc;
+	}
+
+	*dr = gpio;
+	devres_add(dev, dr);
+
+	return 0;
+}
+EXPORT_SYMBOL(devm_gpio_request);
+
+/**
+ *	devm_gpio_request_one - request a single GPIO with initial setup
+ *	@dev:   device to request for
+ *	@gpio:	the GPIO number
+ *	@flags:	GPIO configuration as specified by GPIOF_*
+ *	@label:	a literal description string of this GPIO
+ */
+int devm_gpio_request_one(struct device *dev, unsigned gpio,
+			  unsigned long flags, const char *label)
+{
+	unsigned *dr;
+	int rc;
+
+	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
+	if (!dr)
+		return -ENOMEM;
+
+	rc = gpio_request_one(gpio, flags, label);
+	if (rc) {
+		devres_free(dr);
+		return rc;
+	}
+
+	*dr = gpio;
+	devres_add(dev, dr);
+
+	return 0;
+}
+EXPORT_SYMBOL(devm_gpio_request_one);
+
+/**
+ *      devm_gpio_free - free a GPIO
+ *      @dev: device to free GPIO for
+ *      @gpio: GPIO to free
+ *
+ *      Except for the extra @dev argument, this function takes the
+ *      same arguments and performs the same function as gpio_free().
+ *      This function instead of gpio_free() should be used to manually
+ *      free GPIOs allocated with devm_gpio_request().
+ */
+void devm_gpio_free(struct device *dev, unsigned int gpio)
+{
+
+	WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
+		&gpio));
+}
+EXPORT_SYMBOL(devm_gpio_free);