summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpiolib-devres.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--drivers/gpio/gpiolib-devres.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-devres.c b/drivers/gpio/gpiolib-devres.c
new file mode 100644
index 000000000..16a696249
--- /dev/null
+++ b/drivers/gpio/gpiolib-devres.c
@@ -0,0 +1,484 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * devres.c - managed gpio resources
+ * This file is based on kernel/irq/devres.c
+ *
+ * Copyright (c) 2011 John Crispin <john@phrozen.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>
+
+#include "gpiolib.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;
+}
+
+static void devm_gpiod_release_array(struct device *dev, void *res)
+{
+ struct gpio_descs **descs = res;
+
+ gpiod_put_array(*descs);
+}
+
+static int devm_gpiod_match_array(struct device *dev, void *res, void *data)
+{
+ struct gpio_descs **this = res, **gpios = data;
+
+ return *this == *gpios;
+}
+
+/**
+ * devm_gpiod_get - Resource-managed gpiod_get()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @flags: optional GPIO initialization flags
+ *
+ * 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,
+ enum gpiod_flags flags)
+{
+ return devm_gpiod_get_index(dev, con_id, 0, flags);
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_get);
+
+/**
+ * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @flags: optional GPIO initialization flags
+ *
+ * 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,
+ enum gpiod_flags flags)
+{
+ return devm_gpiod_get_index_optional(dev, con_id, 0, flags);
+}
+EXPORT_SYMBOL_GPL(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
+ * @flags: optional GPIO initialization flags
+ *
+ * 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,
+ enum gpiod_flags flags)
+{
+ struct gpio_desc **dr;
+ struct gpio_desc *desc;
+
+ desc = gpiod_get_index(dev, con_id, idx, flags);
+ if (IS_ERR(desc))
+ return desc;
+
+ /*
+ * For non-exclusive GPIO descriptors, check if this descriptor is
+ * already under resource management by this device.
+ */
+ if (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
+ struct devres *dres;
+
+ dres = devres_find(dev, devm_gpiod_release,
+ devm_gpiod_match, &desc);
+ if (dres)
+ return desc;
+ }
+
+ dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
+ GFP_KERNEL);
+ if (!dr) {
+ gpiod_put(desc);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ *dr = desc;
+ devres_add(dev, dr);
+
+ return desc;
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_get_index);
+
+/**
+ * devm_gpiod_get_from_of_node() - obtain a GPIO from an OF node
+ * @dev: device for lifecycle management
+ * @node: handle of the OF node
+ * @propname: name of the DT property representing the GPIO
+ * @index: index of the GPIO to obtain for the consumer
+ * @dflags: GPIO initialization flags
+ * @label: label to attach to the requested GPIO
+ *
+ * Returns:
+ * On successful request the GPIO pin is configured in accordance with
+ * provided @dflags.
+ *
+ * In case of error an ERR_PTR() is returned.
+ */
+struct gpio_desc *devm_gpiod_get_from_of_node(struct device *dev,
+ const struct device_node *node,
+ const char *propname, int index,
+ enum gpiod_flags dflags,
+ const char *label)
+{
+ struct gpio_desc **dr;
+ struct gpio_desc *desc;
+
+ desc = gpiod_get_from_of_node(node, propname, index, dflags, label);
+ if (IS_ERR(desc))
+ return desc;
+
+ /*
+ * For non-exclusive GPIO descriptors, check if this descriptor is
+ * already under resource management by this device.
+ */
+ if (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
+ struct devres *dres;
+
+ dres = devres_find(dev, devm_gpiod_release,
+ devm_gpiod_match, &desc);
+ if (dres)
+ return desc;
+ }
+
+ dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
+ GFP_KERNEL);
+ if (!dr) {
+ gpiod_put(desc);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ *dr = desc;
+ devres_add(dev, dr);
+
+ return desc;
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_get_from_of_node);
+
+/**
+ * devm_fwnode_gpiod_get_index - get a GPIO descriptor from a given node
+ * @dev: GPIO consumer
+ * @fwnode: firmware node containing GPIO reference
+ * @con_id: function within the GPIO consumer
+ * @index: index of the GPIO to obtain in the consumer
+ * @flags: GPIO initialization flags
+ * @label: label to attach to the requested GPIO
+ *
+ * GPIO descriptors returned from this function are automatically disposed on
+ * driver detach.
+ *
+ * On successful request the GPIO pin is configured in accordance with
+ * provided @flags.
+ */
+struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
+ struct fwnode_handle *fwnode,
+ const char *con_id, int index,
+ enum gpiod_flags flags,
+ const char *label)
+{
+ struct gpio_desc **dr;
+ struct gpio_desc *desc;
+
+ dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
+ GFP_KERNEL);
+ if (!dr)
+ return ERR_PTR(-ENOMEM);
+
+ desc = fwnode_gpiod_get_index(fwnode, con_id, index, flags, label);
+ if (IS_ERR(desc)) {
+ devres_free(dr);
+ return desc;
+ }
+
+ *dr = desc;
+ devres_add(dev, dr);
+
+ return desc;
+}
+EXPORT_SYMBOL_GPL(devm_fwnode_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
+ * @flags: optional GPIO initialization flags
+ *
+ * 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,
+ enum gpiod_flags flags)
+{
+ struct gpio_desc *desc;
+
+ desc = devm_gpiod_get_index(dev, con_id, index, flags);
+ if (gpiod_not_found(desc))
+ return NULL;
+
+ return desc;
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
+
+/**
+ * devm_gpiod_get_array - Resource-managed gpiod_get_array()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @flags: optional GPIO initialization flags
+ *
+ * Managed gpiod_get_array(). GPIO descriptors returned from this function are
+ * automatically disposed on driver detach. See gpiod_get_array() for detailed
+ * information about behavior and return values.
+ */
+struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
+ const char *con_id,
+ enum gpiod_flags flags)
+{
+ struct gpio_descs **dr;
+ struct gpio_descs *descs;
+
+ dr = devres_alloc(devm_gpiod_release_array,
+ sizeof(struct gpio_descs *), GFP_KERNEL);
+ if (!dr)
+ return ERR_PTR(-ENOMEM);
+
+ descs = gpiod_get_array(dev, con_id, flags);
+ if (IS_ERR(descs)) {
+ devres_free(dr);
+ return descs;
+ }
+
+ *dr = descs;
+ devres_add(dev, dr);
+
+ return descs;
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
+
+/**
+ * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @flags: optional GPIO initialization flags
+ *
+ * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
+ * function are automatically disposed on driver detach.
+ * See gpiod_get_array_optional() for detailed information about behavior and
+ * return values.
+ */
+struct gpio_descs *__must_check
+devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
+ enum gpiod_flags flags)
+{
+ struct gpio_descs *descs;
+
+ descs = devm_gpiod_get_array(dev, con_id, flags);
+ if (gpiod_not_found(descs))
+ return NULL;
+
+ return descs;
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
+
+/**
+ * devm_gpiod_put - Resource-managed gpiod_put()
+ * @dev: GPIO consumer
+ * @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_GPL(devm_gpiod_put);
+
+/**
+ * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
+ * @dev: GPIO consumer
+ * @desc: GPIO descriptor to remove resource management from
+ *
+ * Remove resource management from a GPIO descriptor. This is needed when
+ * you want to hand over lifecycle management of a descriptor to another
+ * mechanism.
+ */
+
+void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
+{
+ int ret;
+
+ if (IS_ERR_OR_NULL(desc))
+ return;
+ ret = devres_destroy(dev, devm_gpiod_release,
+ devm_gpiod_match, &desc);
+ /*
+ * If the GPIO descriptor is requested as nonexclusive, we
+ * may call this function several times on the same descriptor
+ * so it is OK if devres_destroy() returns -ENOENT.
+ */
+ if (ret == -ENOENT)
+ return;
+ /* Anything else we should warn about */
+ WARN_ON(ret);
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
+
+/**
+ * devm_gpiod_put_array - Resource-managed gpiod_put_array()
+ * @dev: GPIO consumer
+ * @descs: GPIO descriptor array to dispose of
+ *
+ * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
+ * Normally this function will not be called as the GPIOs will be disposed of
+ * by the resource management code.
+ */
+void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
+{
+ WARN_ON(devres_release(dev, devm_gpiod_release_array,
+ devm_gpiod_match_array, &descs));
+}
+EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
+
+static void devm_gpio_release(struct device *dev, void *res)
+{
+ unsigned *gpio = res;
+
+ gpio_free(*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.
+ */
+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_GPL(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_GPL(devm_gpio_request_one);
+
+static void devm_gpio_chip_release(void *data)
+{
+ struct gpio_chip *gc = data;
+
+ gpiochip_remove(gc);
+}
+
+/**
+ * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key()
+ * @dev: pointer to the device that gpio_chip belongs to.
+ * @gc: the GPIO chip to register
+ * @data: driver-private data associated with this chip
+ * @lock_key: lockdep class for IRQ lock
+ * @request_key: lockdep class for IRQ request
+ *
+ * Context: potentially before irqs will work
+ *
+ * The gpio chip automatically be released when the device is unbound.
+ *
+ * Returns:
+ * A negative errno if the chip can't be registered, such as because the
+ * gc->base is invalid or already associated with a different chip.
+ * Otherwise it returns zero as a success code.
+ */
+int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data,
+ struct lock_class_key *lock_key,
+ struct lock_class_key *request_key)
+{
+ int ret;
+
+ ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key);
+ if (ret < 0)
+ return ret;
+
+ return devm_add_action_or_reset(dev, devm_gpio_chip_release, gc);
+}
+EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);