496 lines
13 KiB
C
496 lines
13 KiB
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(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(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(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,
|
|
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(devm_gpiod_get_from_of_node);
|
|
|
|
/**
|
|
* devm_fwnode_get_index_gpiod_from_child - get a GPIO descriptor from a
|
|
* device's child node
|
|
* @dev: GPIO consumer
|
|
* @con_id: function within the GPIO consumer
|
|
* @index: index of the GPIO to obtain in the consumer
|
|
* @child: firmware node (child of @dev)
|
|
* @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_get_index_gpiod_from_child(struct device *dev,
|
|
const char *con_id, int index,
|
|
struct fwnode_handle *child,
|
|
enum gpiod_flags flags,
|
|
const char *label)
|
|
{
|
|
char prop_name[32]; /* 32 is max size of property name */
|
|
struct gpio_desc **dr;
|
|
struct gpio_desc *desc;
|
|
unsigned int i;
|
|
|
|
dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
|
|
GFP_KERNEL);
|
|
if (!dr)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
|
|
if (con_id)
|
|
snprintf(prop_name, sizeof(prop_name), "%s-%s",
|
|
con_id, gpio_suffixes[i]);
|
|
else
|
|
snprintf(prop_name, sizeof(prop_name), "%s",
|
|
gpio_suffixes[i]);
|
|
|
|
desc = fwnode_get_named_gpiod(child, prop_name, index, flags,
|
|
label);
|
|
if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
|
|
break;
|
|
}
|
|
if (IS_ERR(desc)) {
|
|
devres_free(dr);
|
|
return desc;
|
|
}
|
|
|
|
*dr = desc;
|
|
devres_add(dev, dr);
|
|
|
|
return desc;
|
|
}
|
|
EXPORT_SYMBOL(devm_fwnode_get_index_gpiod_from_child);
|
|
|
|
/**
|
|
* 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 (IS_ERR(desc)) {
|
|
if (PTR_ERR(desc) == -ENOENT)
|
|
return NULL;
|
|
}
|
|
|
|
return desc;
|
|
}
|
|
EXPORT_SYMBOL(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(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 (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
|
|
return NULL;
|
|
|
|
return descs;
|
|
}
|
|
EXPORT_SYMBOL(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(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(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(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(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);
|