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linux-hardened/drivers/regulator/gpio-regulator.c
Kees Cook a86854d0c5 treewide: devm_kzalloc() -> devm_kcalloc() 
The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

        devm_kzalloc(handle, a * b, gfp)

with:
        devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

        devm_kzalloc(handle, a * b * c, gfp)

with:

        devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  devm_kzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  devm_kzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
  devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * E2
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00

430 lines
11 KiB
C
Raw Blame History

/*
* gpio-regulator.c
*
* Copyright 2011 Heiko Stuebner <heiko@sntech.de>
*
* based on fixed.c
*
* Copyright 2008 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*
* Copyright (c) 2009 Nokia Corporation
* Roger Quadros <ext-roger.quadros@nokia.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This is useful for systems with mixed controllable and
* non-controllable regulators, as well as for allowing testing on
* systems with no controllable regulators.
*/
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/gpio-regulator.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
struct gpio_regulator_data {
struct regulator_desc desc;
struct regulator_dev *dev;
struct gpio *gpios;
int nr_gpios;
struct gpio_regulator_state *states;
int nr_states;
int state;
};
static int gpio_regulator_get_value(struct regulator_dev *dev)
{
struct gpio_regulator_data *data = rdev_get_drvdata(dev);
int ptr;
for (ptr = 0; ptr < data->nr_states; ptr++)
if (data->states[ptr].gpios == data->state)
return data->states[ptr].value;
return -EINVAL;
}
static int gpio_regulator_set_voltage(struct regulator_dev *dev,
int min_uV, int max_uV,
unsigned *selector)
{
struct gpio_regulator_data *data = rdev_get_drvdata(dev);
int ptr, target = 0, state, best_val = INT_MAX;
for (ptr = 0; ptr < data->nr_states; ptr++)
if (data->states[ptr].value < best_val &&
data->states[ptr].value >= min_uV &&
data->states[ptr].value <= max_uV) {
target = data->states[ptr].gpios;
best_val = data->states[ptr].value;
if (selector)
*selector = ptr;
}
if (best_val == INT_MAX)
return -EINVAL;
for (ptr = 0; ptr < data->nr_gpios; ptr++) {
state = (target & (1 << ptr)) >> ptr;
gpio_set_value_cansleep(data->gpios[ptr].gpio, state);
}
data->state = target;
return 0;
}
static int gpio_regulator_list_voltage(struct regulator_dev *dev,
unsigned selector)
{
struct gpio_regulator_data *data = rdev_get_drvdata(dev);
if (selector >= data->nr_states)
return -EINVAL;
return data->states[selector].value;
}
static int gpio_regulator_set_current_limit(struct regulator_dev *dev,
int min_uA, int max_uA)
{
struct gpio_regulator_data *data = rdev_get_drvdata(dev);
int ptr, target = 0, state, best_val = 0;
for (ptr = 0; ptr < data->nr_states; ptr++)
if (data->states[ptr].value > best_val &&
data->states[ptr].value >= min_uA &&
data->states[ptr].value <= max_uA) {
target = data->states[ptr].gpios;
best_val = data->states[ptr].value;
}
if (best_val == 0)
return -EINVAL;
for (ptr = 0; ptr < data->nr_gpios; ptr++) {
state = (target & (1 << ptr)) >> ptr;
gpio_set_value_cansleep(data->gpios[ptr].gpio, state);
}
data->state = target;
return 0;
}
static struct regulator_ops gpio_regulator_voltage_ops = {
.get_voltage = gpio_regulator_get_value,
.set_voltage = gpio_regulator_set_voltage,
.list_voltage = gpio_regulator_list_voltage,
};
static struct gpio_regulator_config *
of_get_gpio_regulator_config(struct device *dev, struct device_node *np,
const struct regulator_desc *desc)
{
struct gpio_regulator_config *config;
const char *regtype;
int proplen, gpio, i;
int ret;
config = devm_kzalloc(dev,
sizeof(struct gpio_regulator_config),
GFP_KERNEL);
if (!config)
return ERR_PTR(-ENOMEM);
config->init_data = of_get_regulator_init_data(dev, np, desc);
if (!config->init_data)
return ERR_PTR(-EINVAL);
config->supply_name = config->init_data->constraints.name;
if (of_property_read_bool(np, "enable-active-high"))
config->enable_high = true;
if (of_property_read_bool(np, "enable-at-boot"))
config->enabled_at_boot = true;
of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
config->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0);
if (config->enable_gpio < 0 && config->enable_gpio != -ENOENT)
return ERR_PTR(config->enable_gpio);
/* Fetch GPIOs. - optional property*/
ret = of_gpio_count(np);
if ((ret < 0) && (ret != -ENOENT))
return ERR_PTR(ret);
if (ret > 0) {
config->nr_gpios = ret;
config->gpios = devm_kcalloc(dev,
config->nr_gpios, sizeof(struct gpio),
GFP_KERNEL);
if (!config->gpios)
return ERR_PTR(-ENOMEM);
proplen = of_property_count_u32_elems(np, "gpios-states");
/* optional property */
if (proplen < 0)
proplen = 0;
if (proplen > 0 && proplen != config->nr_gpios) {
dev_warn(dev, "gpios <-> gpios-states mismatch\n");
proplen = 0;
}
for (i = 0; i < config->nr_gpios; i++) {
gpio = of_get_named_gpio(np, "gpios", i);
if (gpio < 0) {
if (gpio != -ENOENT)
return ERR_PTR(gpio);
break;
}
config->gpios[i].gpio = gpio;
config->gpios[i].label = config->supply_name;
if (proplen > 0) {
of_property_read_u32_index(np, "gpios-states",
i, &ret);
if (ret)
config->gpios[i].flags =
GPIOF_OUT_INIT_HIGH;
}
}
}
/* Fetch states. */
proplen = of_property_count_u32_elems(np, "states");
if (proplen < 0) {
dev_err(dev, "No 'states' property found\n");
return ERR_PTR(-EINVAL);
}
config->states = devm_kcalloc(dev,
proplen / 2,
sizeof(struct gpio_regulator_state),
GFP_KERNEL);
if (!config->states)
return ERR_PTR(-ENOMEM);
for (i = 0; i < proplen / 2; i++) {
of_property_read_u32_index(np, "states", i * 2,
&config->states[i].value);
of_property_read_u32_index(np, "states", i * 2 + 1,
&config->states[i].gpios);
}
config->nr_states = i;
config->type = REGULATOR_VOLTAGE;
ret = of_property_read_string(np, "regulator-type", &regtype);
if (ret >= 0) {
if (!strncmp("voltage", regtype, 7))
config->type = REGULATOR_VOLTAGE;
else if (!strncmp("current", regtype, 7))
config->type = REGULATOR_CURRENT;
else
dev_warn(dev, "Unknown regulator-type '%s'\n",
regtype);
}
return config;
}
static struct regulator_ops gpio_regulator_current_ops = {
.get_current_limit = gpio_regulator_get_value,
.set_current_limit = gpio_regulator_set_current_limit,
};
static int gpio_regulator_probe(struct platform_device *pdev)
{
struct gpio_regulator_config *config = dev_get_platdata(&pdev->dev);
struct device_node *np = pdev->dev.of_node;
struct gpio_regulator_data *drvdata;
struct regulator_config cfg = { };
int ptr, ret, state;
drvdata = devm_kzalloc(&pdev->dev, sizeof(struct gpio_regulator_data),
GFP_KERNEL);
if (drvdata == NULL)
return -ENOMEM;
if (np) {
config = of_get_gpio_regulator_config(&pdev->dev, np,
&drvdata->desc);
if (IS_ERR(config))
return PTR_ERR(config);
}
drvdata->desc.name = kstrdup(config->supply_name, GFP_KERNEL);
if (drvdata->desc.name == NULL) {
dev_err(&pdev->dev, "Failed to allocate supply name\n");
return -ENOMEM;
}
if (config->nr_gpios != 0) {
drvdata->gpios = kmemdup(config->gpios,
config->nr_gpios * sizeof(struct gpio),
GFP_KERNEL);
if (drvdata->gpios == NULL) {
dev_err(&pdev->dev, "Failed to allocate gpio data\n");
ret = -ENOMEM;
goto err_name;
}
drvdata->nr_gpios = config->nr_gpios;
ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios);
if (ret) {
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev,
"Could not obtain regulator setting GPIOs: %d\n",
ret);
goto err_memgpio;
}
}
drvdata->states = kmemdup(config->states,
config->nr_states *
sizeof(struct gpio_regulator_state),
GFP_KERNEL);
if (drvdata->states == NULL) {
dev_err(&pdev->dev, "Failed to allocate state data\n");
ret = -ENOMEM;
goto err_stategpio;
}
drvdata->nr_states = config->nr_states;
drvdata->desc.owner = THIS_MODULE;
drvdata->desc.enable_time = config->startup_delay;
/* handle regulator type*/
switch (config->type) {
case REGULATOR_VOLTAGE:
drvdata->desc.type = REGULATOR_VOLTAGE;
drvdata->desc.ops = &gpio_regulator_voltage_ops;
drvdata->desc.n_voltages = config->nr_states;
break;
case REGULATOR_CURRENT:
drvdata->desc.type = REGULATOR_CURRENT;
drvdata->desc.ops = &gpio_regulator_current_ops;
break;
default:
dev_err(&pdev->dev, "No regulator type set\n");
ret = -EINVAL;
goto err_memstate;
}
/* build initial state from gpio init data. */
state = 0;
for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) {
if (config->gpios[ptr].flags & GPIOF_OUT_INIT_HIGH)
state |= (1 << ptr);
}
drvdata->state = state;
cfg.dev = &pdev->dev;
cfg.init_data = config->init_data;
cfg.driver_data = drvdata;
cfg.of_node = np;
if (gpio_is_valid(config->enable_gpio)) {
cfg.ena_gpio = config->enable_gpio;
cfg.ena_gpio_initialized = true;
}
cfg.ena_gpio_invert = !config->enable_high;
if (config->enabled_at_boot) {
if (config->enable_high)
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
else
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
} else {
if (config->enable_high)
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
else
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
}
drvdata->dev = regulator_register(&drvdata->desc, &cfg);
if (IS_ERR(drvdata->dev)) {
ret = PTR_ERR(drvdata->dev);
dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
goto err_memstate;
}
platform_set_drvdata(pdev, drvdata);
return 0;
err_memstate:
kfree(drvdata->states);
err_stategpio:
gpio_free_array(drvdata->gpios, drvdata->nr_gpios);
err_memgpio:
kfree(drvdata->gpios);
err_name:
kfree(drvdata->desc.name);
return ret;
}
static int gpio_regulator_remove(struct platform_device *pdev)
{
struct gpio_regulator_data *drvdata = platform_get_drvdata(pdev);
regulator_unregister(drvdata->dev);
gpio_free_array(drvdata->gpios, drvdata->nr_gpios);
kfree(drvdata->states);
kfree(drvdata->gpios);
kfree(drvdata->desc.name);
return 0;
}
#if defined(CONFIG_OF)
static const struct of_device_id regulator_gpio_of_match[] = {
{ .compatible = "regulator-gpio", },
{},
};
MODULE_DEVICE_TABLE(of, regulator_gpio_of_match);
#endif
static struct platform_driver gpio_regulator_driver = {
.probe = gpio_regulator_probe,
.remove = gpio_regulator_remove,
.driver = {
.name = "gpio-regulator",
.of_match_table = of_match_ptr(regulator_gpio_of_match),
},
};
static int __init gpio_regulator_init(void)
{
return platform_driver_register(&gpio_regulator_driver);
}
subsys_initcall(gpio_regulator_init);
static void __exit gpio_regulator_exit(void)
{
platform_driver_unregister(&gpio_regulator_driver);
}
module_exit(gpio_regulator_exit);
MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
MODULE_DESCRIPTION("gpio voltage regulator");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:gpio-regulator");
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