https://github.com/torvalds/linux
Tip revision: 3906fe9bb7f1a2c8667ae54e967dc8690824f4ea authored by Linus Torvalds on 25 October 2021, 18:30:31 UTC
Linux 5.15-rc7
Linux 5.15-rc7
Tip revision: 3906fe9
gpiolib-devres.c
/* 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);
}
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_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);
/**
* 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_GPL(devm_gpio_free);
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);